GH1 DOF Vs HMC-150/HPX170

[studio1972]

Not sure if anybody has already done this, but I was interested in what the GH1 might give me in terms of DOF compared to my HMC151. These calculations were done with the stock GH1 lens which is designed with video in mind. Obviously the results would be different with prime lenses etc.

Distance to subject = 5m
35mm equivelant focal length = 100mm
Aperture fully open in both cases

HMC = 2.45m at f/2 13.8mm
GH1 = 1.83m at f/5.6 50mm

Distance to subject = 5m
35mm equivelant focal length = 200mm
Aperture fully open in both cases

HMC = 0.7m at f/2.4 27.6mm
GH1 = 0.44m at f/5.6 100mm

I used this online calculator:

http://www.cambridgeincolour.com/tutorials/DOF-calculator.htm

It seems like the GH1 is capable of shallower DOF, but not so much as you might expect given that the sensor is 4 times as wide. I haven't done the maths, but I would imagine that an EX1 might come out with similar figures to the GH1 as it has a better lens than the HMC and a slightly larger sensor.

[Martti Ekstrand]

The fall-off of focus outside the DOF is greater with a bigger sensor than these numbers indicate. Which shows in the image.

[studio1972]

The fall-off of focus outside the DOF is greater with a bigger sensor than these numbers indicate. Which shows in the image.

Ok. I've just done the same calcs for the EX1, and it comes out at 1.68m and 0.41m respectively. This means it has slightly shallower DOF than the GH1.

Regarding your point about the larger sensor, I believe that this is counteracted by the narrow aperture of the GH1 lens. Of course, you can get other lenses for the camera.

Regards

Stuart

[Tim Joy]

You can get razor thin DOF with the GH1 and the right lens, so the question is- How much do you want?
Compared to 1/3" cameras, you have much more control, and you can get shallow DOF in almost any shot with a reasonably fast lens above about 35mm, or shooting CU with wide lenses.

[studio1972]

I was talking about the stock lens. Obviously with another lens the situation would be different. What I am saying is that if you intend to use the stock lens (which has a reasonable zoom range etc.) then you are going to get DOF in the same ball park as an EX1 and not much better than a 1/3 camera. The GH1 is much cheaper than these, so I'm not trying to slate it, I was just a bit surprised when I worked it out, and thought people might be interested as it seems most people seem to expect shallower DOF on the 4/3 camera.

[Ben_B]

The nice thing about a camera like the GH1 is that you can get shallow DOF in almost any situation if you need it. The HPX170 can get very shallow DOF if you need it, but you have to be shooting wide open, get far back, etc.

Here's some HPX170 screen grabs from a friend of mine when we were shooting around with the HPX and the GH1 that show off potential DOF of the HPX.

http://photos-f.ak.fbcdn.net/photos-ak-sf2p/v5205/169/86/725925057/n725925057_8312069_3402424.jpg

http://photos-b.ak.fbcdn.net/photos-ak-sf2p/v5205/169/86/725925057/n725925057_8312065_7101552.jpg

[Tim Joy]

Ahh. I see your point. Yes, it is close to the 1/3" cameras but just that little bit of extra shallowness is really nice sometimes.

[Barry_Green]

At the same aperture, the GH1 will be astoundingly shallower than the EX1 or HPX170 or HMC150. If you're going to go comparing f/2 to f/5.6, then of course you're going to end up with the results you got. But when are you going to be shooting f/2 on one camera, and in the exact same circumstances shooting f/5.6 on another camera? That's not gonna happen.

Aperture to aperture, the GH1 is going to be extremely much shallower.

[Ben_B]

And in the end, that's why many of us bought it.

[studio1972]

But when are you going to be shooting f/2 on one camera, and in the exact same circumstances shooting f/5.6 on another camera? That's not gonna happen.

Both cameras are fully open in this situation, I often have my HMC lens fully open, and I would do the same with the GH1 if I had one, seems like a perfectly reasonable comparison to me. Why would you not use the HMC at f/2.0 in a similar situation?

Surely you are not seriously arguing that you would have the same aperture in the same situation with a 1/3 camera as you would with a 4/3 camera?


Aperture to aperture, the GH1 is going to be extremely much shallower.

That's undoubtably true, but also a straw man. The EX1 has a lens with a wide zoom range at f/1.9, if such a lens could even be produced for a 4/3 sensor camera it would be enormous and would cost a fortune. The stock lens on the GH1 can go no more open then f/5.6 at the zooms I calculated.

Yes, you could use a prime lens on the GH1, but then you would have much less flexibility. An aperture to aperture comparison is really meaningless given that you would be falsely restricting the EX1/HMC to carry out this comparison.

[Barry_Green]

Both cameras are fully open in this situation, I often have my HMC lens fully open, and I would do the same with the GH1 if I had one, seems like a perfectly reasonable comparison to me. Why would you not use the HMC at f/2.0 in a similar situation?
Because the HMC would be overexposing the shot by two stops!


Surely you are not seriously arguing that you would have the same aperture in the same situation with a 1/3 camera as you would with a 4/3 camera?
Of course you would. Why wouldn't you? Sensor size has nothing to do with the amount of light that you want to have entering the lens. In fact, in normal circumstances I'd want the GH1's lens *more* wide open than the HMC150's whenever possible. Why? Because I prefer the GH1's look at 100 ISO. So assuming equivalent shutter speed, the HMC150's native 500 ISO would dictate a certain f-stop, and setting the GH1 to 100 ISO would mean needing about two stops' more open iris for proper exposure.



That's undoubtably true, but also a straw man.
Why on earth do you say it's a "straw man"?


The EX1 has a lens with a wide zoom range at f/1.9
The EX1 does not have a lens with a wide zoom range at f/1.9. It is only f/1.9 at the most wide-angle end. It ramps (just like the GH1 and all other lenses of similar design), it's nowhere near f/1.9 when at full tele. It just lies to you by not TELLING you that it's ramping, but it is.


Yes, you could use a prime lens on the GH1, but then you would have much less flexibility. An aperture to aperture comparison is really meaningless given that you would be falsely restricting the EX1/HMC to carry out this comparison.
How? If you assume that the GH1 is going to be able to get accurate exposure at whatever zoom setting you're at, then you're going to have to set the EX1 or HMC to the same aperture, or deeper, because both cameras are inherently faster.

Even if you set them to the same ISO, you'll need the same aperture to get proper exposure. And the GH1 will slay in DOF in that circumstance.

So the only way your comparison holds valid is if you're either a) willing to accept grossly underexposed footage on the GH1, which seems like a false argument, or b) using ND filters on the EX1/HMC.

In any case, look -- I own a GH1, and an HMC150, and an HPX170, and I don't need to go resorting to calculators to try to prove a point which is obviously and easily disprovable in simple usage. Testing trumps theory every time. Actually grab the cameras and go out and shoot some footage and you'll find out real quick, very quickly, the GH1 has extremely shallower DOF than any 1/3" camera no matter which way you slice it.

[studio1972]

Because the HMC would be overexposing the shot by two stops!

You could use an ND filter on the HMC, also this would surely depend on the ISO.




Of course you would. Why wouldn't you?

Here's some very obvious reasons:

1. You might want shallow DOF, and would therefore want to have the iris fully open on the HMC

2. The light level might require you to open up the iris more than 5.6

3. The 2 sensors presumably don't have identical ISO


Sensor size has nothing to do with the amount of light that you want to have entering the lens.

Yes it does, If I want shallow DOF with a 1/3 sensor I will need a wider aperture for the same angle of view.




In fact, in normal circumstances I'd want the GH1's lens *more* wide open than the HMC150's whenever possible. Why? Because I prefer the GH1's look at 100 ISO. So assuming equivalent shutter speed, the HMC150's native 500 ISO would dictate a certain f-stop, and setting the GH1 to 100 ISO would mean needing about two stops' more open iris for proper exposure.

Why on earth do you say it's a "straw man"?

Because you could simply use the built in ND filters in the HMC to reduce the amount of light without having to close the iris. It is a straw man argument because you are deliberately ignoring factors such as this.



The EX1 does not have a lens with a wide zoom range at f/1.9. It is only f/1.9 at the most wide-angle end. It ramps (just like the GH1 and all other lenses of similar design), it's nowhere near f/1.9 when at full tele. It just lies to you by not TELLING you that it's ramping, but it is.

It's still a lot wider than f/5.6 though I would imagine. Let's say it's f/2.4, that still puts the DOF only slightly wider than the GH1 stock lens.



How? If you assume that the GH1 is going to be able to get accurate exposure at whatever zoom setting you're at, then you're going to have to set the EX1 or HMC to the same aperture, or deeper, because both cameras are inherently faster.

Even if you set them to the same ISO, you'll need the same aperture to get proper exposure. And the GH1 will slay in DOF in that circumstance.

ND Filters


So the only way your comparison holds valid is if you're either a) willing to accept grossly underexposed footage on the GH1, which seems like a false argument, or b) using ND filters on the EX1/HMC.

b it is then :thumbup:


In any case, look -- I own a GH1, and an HMC150, and an HPX170, and I don't need to go resorting to calculators to try to prove a point which is obviously and easily disprovable in simple usage. Testing trumps theory every time. Actually grab the cameras and go out and shoot some footage and you'll find out real quick, very quickly, the GH1 has extremely shallower DOF than any 1/3" camera no matter which way you slice it.

Are you talking about the stock lens? If so I don't know why the laws of physics suddenly break down just because you assert it? I have just tried comparing my HMC fully open to my 450d at f/5.6 with a similar viewing angle (160mm 35mm equivalent) and the DOF looks similar to me, which stacks up with my calculations.

[Barry_Green]

I'm not sure why real-world experience has to take a back seat to calculators, but let me try this a different way:

The GH1 delivers shallower DOF than the 1/3" cameras.

I'm *extremely* well versed in what one can do to get the maximum performance out of a 1/3" camera in terms of shallow DOF. They do not compare.

If your mileage varies, it is only because you want it to, to prove an esoteric point.

In any practical shooting situation, you will get shallower DOF out of the GH1. And if you want to push things, putting a 50mm f/1.4 lens on a GH1 costs maybe fifty bucks and gives you phenomenally shallower DOF, and takes about 10 seconds to accomplish.

The 150 is a better video camera in all ways (except ultimate sharpness, when the GH1 is behaving at its best) but to assert that they're comparable in DOF terms simply denies the reality of actually using the products.

[studio1972]

I'm not sure why real-world experience has to take a back seat to calculators, but let me try this a different way:

The GH1 delivers shallower DOF than the 1/3" cameras.

I'm *extremely* well versed in what one can do to get the maximum performance out of a 1/3" camera in terms of shallow DOF. They do not compare.

If your mileage varies, it is only because you want it to, to prove an esoteric point.

In any practical shooting situation, you will get shallower DOF out of the GH1. And if you want to push things, putting a 50mm f/1.4 lens on a GH1 costs maybe fifty bucks and gives you phenomenally shallower DOF, and takes about 10 seconds to accomplish.

The 150 is a better video camera in all ways (except ultimate sharpness, when the GH1 is behaving at its best) but to assert that they're comparable in DOF terms simply denies the reality of actually using the products.

I said in my original post that I was only comparing the stock lens to the HMC. The GH1 does have shallower DOF in this scenario as per the calculations, but not by much!

Putting a f/1.4 prime lens on it changes everything, I never denied this. This is another straw man!

So are you saying that my calculations are wrong? If so, maybe you can explain why, or provide some proof in terms of images? As I said I have just compared the HMC to my 450d and the DOF is similar, with the 450d at f/5.6 as the GH1 would be. Are you saying that I'm making it up? Do I need to back this up with images for you to believe that what I have said, based on standard calculations, is true?

[John Caballero]

Do I need to back this up with images for you to believe that what I have said, based on standard calculations, is true?

You have to actually go get a GH1 and put it next to the HMC and shoot along. You have to prove your point in the real world, out in the field with proper samples. Then if you are right you would have proven your point with actual images from the cameras you are debating about.

[Barry_Green]

"only comparing the stock lens" is in itself a straw man. The first thing many of us do is pull the stock lens off! To ignore that is to tie one man's hands behind his back and then say "see, I can beat this guy up". What's the point in that?

What I'm saying is: calculations don't mean jack squat, when what you do in the real world under real shooting scenarios delivers different results.

What your calculator tells you, and what the real images show, are going to differ for a number of reasons -- not the least of which is that when something's in focus on the GH1, it's way sharper than it is on the HMC150. Therefore, the perceived depth of field is going to be notably shorter on the GH1. The transition from in-focus to out-of-focus is more noticeable on the GH1. Yet that isn't accounted for in an online DOF calculator.

I can force a 35mm movie camera to deliver deeper depth of field than an HMC150. Does that mean I should go around thinking that the HMC150 has shallower DOF than a 35mm movie camera? Of course not, the notion is silly on the face of it.

Yet, seeing as the GH1 has nearly the same sensor size as a 35mm movie camera, that's the premise you're asking us to accept. And, as a logical individual and an experienced shooter, I reject that notion.

If I can squeeze some time in, maybe I'll do some sample shots. It's too bad I don't live in an area where I can find some straw, I'd love to use a "straw man" as my subject. :)

[Barry_Green]

You have to actually go get a GH1 and put it next to the HMC and shoot along. You have to prove your point in the real world, out in the field with proper samples. Then if you are right you would have proven your point with actual images from the cameras you are debating about.
But only if you want to hamper the GH1 by always forcing it to be several stops slower than the 150.

[Barry_Green]

Okay, the great "straw man shootout 2009" is now complete.

I constructed a "straw man". Put it on my porch railing, and set the cameras as far away as I could get them (about 6'). The background is intensely detailed trees, about 40' behind the "straw man".

Both cameras opened up to their maximum iris. In the case of the HMC150, that's about f/2.0, in the case of the GH1 that was f/5.8. (I say "about f/2.0" because it was set to read "open"; if I stopped it down one tick it read out as "f/2.4", so it was more open than f/2.4, putting it at "about" f/2.0). The HMC150 had ND1 employed to keep the iris as open as possible. The GH1 was set to ISO 100 to keep the iris as open as possible.

GH1 was 1/50th shutter. I actually cheated a little to help the HMC150; I used 1/100, trying to get the proper exposure in the background. That's unfair, I should have stopped down the iris, but hey, I'm trying to put the HMC150 in its best possible light for purposes of the comparison.

HMC150 and GH1 were both zoomed in to the point where they could see the straw man top to bottom in the frame. On the GH1 that was about 120mm, on the HMC150 it was 33.3mm.

Here are the results. HMC150 on the left, GH1 on the right. If the DOF looks exactly the same to you, so be it. I happen to see a substantial difference, as expected. (note, this image has been resized down to fit on most people's screens; the originals are available after the pic).

http://dvxuser.com/barry/Straw-Combined.jpg

For those who want to examine the original 1080p frames, here they are:
http://dvxuser.com/barry/GH1-Straw-Man.jpg
http://dvxuser.com/barry/HMC150-Straw-2.jpg

[studio1972]

You have to actually go get a GH1 and put it next to the HMC and shoot along. You have to prove your point in the real world, out in the field with proper samples. Then if you are right you would have proven your point with actual images from the cameras you are debating about.

Well, that's kind of difficult for me to without having a GH1, but I've taken an image with the HMC and with a 450d with aperture f/5.6. The images are attached. The DOF from the HMC is slightly less shallow, as I said, but not that much. I think that proves my point pretty well, given that I thought my original point was only a simple calculation based on the specs of the HMC and GH1.

[Ben_B]

Thanks Barry. GH1 wins for sure, and the HMC shot is STILL OVEREXPOSED. Also the expression on the straw man's face is exactly what I imagined your face to look like arguing this point. f/5.6 beating the crap out of f/2...wow.

To address some things mentioned earlier. You can use ND filters on the GH1 if you want.

Claiming that using Prime Lenses on the GH1 gives you less flexibility is totally preposterous: you can't use prime lenses on the HMC-150, you're stuck with the stock lens! I can use just about any lens every made on the GH1 and I can carry them around in a little bag and swap whenever I want, all I need to do is buy a few $100 adapters. People are using everything from C-Mount security camera lenses to PL cinema lenses on the thing and everything in between. If you want to throw a Nikon lens on the HMC-150 that'll set you back about $2,000 for the adapter and the rail system. And with the GH1 you're saving about $4000 ($4900 if you speak Japanese and bought body-only) cash vs HMC + Adapter which you have to spend on all the glass you want to get all the flexibility in the world. On top of that if you don't think I can find a zoom that performs as well as the HMC's stock lens for that amount of coin then I propose you send me the $2000 difference between the two camera's stock configurations (although more fair would be the $2900 between GH1 body only and the HMC) and I'll send you some pictures. Tell me which camera has less flexibility!

[Huy Vu]

This is just a ridiculous comparison. You're a) Not comparing the two camera at the same focal length and b) Not comparing them at the same aperture.

[Cranky]

Wow. I know that one is a still cam and another is a frame grab from a video cam, but... wow. I think that the 150's image can be improved by turning sharpening down, it is way oversharpened, with heavy aliasing and noise. This hi-freq noise in the leaves gives it sharper deeper-DOFy look.

[Ben_B]

That's Barry's point. Obviously at same focal length and aperture the GH1 would destroy the HMC...it did so at a smaller aperture!

[Barry_Green]

This is just a ridiculous comparison. You're a) Not comparing the two camera at the same focal length and b) Not comparing them at the same aperture.
I agree 1,000,000%.

[Barry_Green]

Wow. I know that one is a still cam and another is a frame grab from a video cam, but... wow.
Both were shot in 1080/24p mode, and both are frame grabs from the video stream.


I think that the 150's image can be improved by turning sharpening down, it is way oversharpened, with heavy aliasing and noise. This hi-freq noise in the leaves gives it sharper deeper-DOFy look.
It was somewhat oversharpened, yes; I didn't bother looking at the settings before shooting, and it turns out that the HMC150 was at +2 detail, +1 v-detail, and coring -2. None of those are outrageous settings for a 150. If it was +7/+7/-7, I would go reshoot it, but +2/+1/-2 is reasonable enough.

[Ben_B]

You cannot agree more than 100% Barry, by definition 100% is as much as you can agree. I say you go shoot a comparision, showing us you agreeing at 100% vs 1,000,000% and I will wager that they will look the same. Technically they are, despite the fact the numbers are different, and I'd imagine that they way they look in real life looks the same as well. I demand pictures to prove this though!

[studio1972]

This is just a ridiculous comparison. You're a) Not comparing the two camera at the same focal length and b) Not comparing them at the same aperture.

The comparison was at the same equivelant focal length (taking into acount the crop factors) and the maximum aperture of the cameras concerned. Why is that ridiculous?

[Barry_Green]

Because you're handicapping the GH1 into only using its wildly slow stock lens. The GH1 costs $2,000 less than an HMC150. You could spend $2,000 on lenses, have equivalent expense, but have a wide variety of f/1.4 or f/1.8 lenses to choose from.

It's not apples to apples in any way. It's artificially limited.

The only way this would be fair is if the GH1's lens was not exchangeable.

Furthermore, you're limiting the comparison to only the lighting range wherein the 150 can be two or three stops more open than the GH1. In real world circumstances, where you're shooting at a 5.6 on the 150, you'll find the GH1's DOF strikingly shallower.

By the way, I've been making a somewhat similar argument to yours, so I know exactly where you're coming from -- I've been saying that the fixed-lens Scarlet is not going to deliver noticeably shallower DOF than today's crop of 1/3" or 1/2" cams, and for the same reason (because the Scarlet's lens, as of the last specs we knew, only opens to a maximum of f/2.8). However, at equivalent aperture, the Scarlet will be shallower. The argument partly holds only in that even a 2/3" chip doesn't really deliver anything that could be classified as "shallow" DOF unless you're at a very long telephoto setting and with a wide-open lens.

Now with the GH1 that's not the case, so the logic doesn't apply, because the GH1's lens *is* exchangeable. And extremely inexpensively so.

[studio1972]

I think you totally missunderstood what I was saying. It is great that the gh1 can change lenses and that indeed adds to it's versitility. I was merely meaning that using a prime lens requires a certain type of situation where as a zoom lens allows you to frame a shot in a more flexible way. This was why I compared the hmc to the gh1 with it's zoom lens rather than a 50mm 1.4 etc.


Thanks Barry. GH1 wins for sure, and the HMC shot is STILL OVEREXPOSED. Also the expression on the straw man's face is exactly what I imagined your face to look like arguing this point. f/5.6 beating the crap out of f/2...wow.

To address some things mentioned earlier. You can use ND filters on the GH1 if you want.

Claiming that using Prime Lenses on the GH1 gives you less flexibility is totally preposterous: you can't use prime lenses on the HMC-150, you're stuck with the stock lens! I can use just about any lens every made on the GH1 and I can carry them around in a little bag and swap whenever I want, all I need to do is buy a few $100 adapters. People are using everything from C-Mount security camera lenses to PL cinema lenses on the thing and everything in between. If you want to throw a Nikon lens on the HMC-150 that'll set you back about $2,000 for the adapter and the rail system. And with the GH1 you're saving about $4000 ($4900 if you speak Japanese and bought body-only) cash vs HMC + Adapter which you have to spend on all the glass you want to get all the flexibility in the world. On top of that if you don't think I can find a zoom that performs as well as the HMC's stock lens for that amount of coin then I propose you send me the $2000 difference between the two camera's stock configurations (although more fair would be the $2900 between GH1 body only and the HMC) and I'll send you some pictures. Tell me which camera has less flexibility!

[Cranky]

Well, the GH1 is not sold as body-only anywhere in the U.S., I just googled. So the point of using (or not using) the kit lens is moot.

For $700 this should better be a good lens, after all my Nikon 55-200 lens costs only $230, is about as slow as the GH1 kit lens, and has built-in stabilization. The 18-55mm is as slow, and it costs less than $200. Why the GH1's lens is so expensive?

[studio1972]

I agree with you on most of this. I guess we are coming from different angles though. For example, in my work swapping lenses over would be impractical. So if I had a gh1 I would want to use the stock lens 99% of the time. Also, living in the north of England ensures that I very rarely have to stop down the iris, I probably spend most of my time at wide open +12 gain tbh.

For somebody shooting short films in a nice sunny country like your's though....


Because you're handicapping the GH1 into only using its wildly slow stock lens. The GH1 costs $2,000 less than an HMC150. You could spend $2,000 on lenses, have equivalent expense, but have a wide variety of f/1.4 or f/1.8 lenses to choose from.

It's not apples to apples in any way. It's artificially limited.

The only way this would be fair is if the GH1's lens was not exchangeable.

Furthermore, you're limiting the comparison to only the lighting range wherein the 150 can be two or three stops more open than the GH1. In real world circumstances, where you're shooting at a 5.6 on the 150, you'll find the GH1's DOF strikingly shallower.

By the way, I've been making a somewhat similar argument to yours, so I know exactly where you're coming from -- I've been saying that the fixed-lens Scarlet is not going to deliver noticeably shallower DOF than today's crop of 1/3" or 1/2" cams, and for the same reason (because the Scarlet's lens, as of the last specs we knew, only opens to a maximum of f/2.8). However, at equivalent aperture, the Scarlet will be shallower. The argument partly holds only in that even a 2/3" chip doesn't really deliver anything that could be classified as "shallow" DOF unless you're at a very long telephoto setting and with a wide-open lens.

Now with the GH1 that's not the case, so the logic doesn't apply, because the GH1's lens *is* exchangeable. And extremely inexpensively so.

[Huy Vu]

I I was merely meaning that using a prime lens requires a certain type of situation where as a zoom lens allows you to frame a shot in a more flexible way.

It doesn't sound like you've ever shot with a prime lens in a video situation before. While what you say sounds fine in theory, in practice this is seldom the case. The vast majority of 35mm adapter and VDSLR user actually uses prime lenses and prefers them to zoom because they're cheaper, faster and lighter. It takes a few seconds to swap lenses on set. A high quality zoom lenses can easily cost you a grand or more where as for the same amount of money you can have a set of fast primes to cover that same range. You'll almost never find yourself in a situation where you say "Hm, I wish I have a 38mm lens instead of that 35mm"; it's easy enough to just move in or out a bit. That's why it doesn't make any sense to artificially limited the GH1 to a slower zoom lens when many GH1 users actually does use primes.

Also, you can adapt any lenses to the micro 4/3 mount, and there are fast zooms out there in the 2.8 range, so why not include those?

[Barry_Green]

For $700 this should better be a good lens, after all my Nikon 55-200 lens costs only $230, is about as slow as the GH1 kit lens, and has built-in stabilization. The 18-55mm is as slow, and it costs less than $200. Why the GH1's lens is so expensive?
Well, first of all a 55-200 is a 3.5x zoom range. 18-55 is a 3x zoom range. The GH1 is a 10x zoom.

Secondly, it's a very wide lens, at 14mm.

Third, it has silent autofocus for video built in.

Fourth, it has mega optical image stabilization built in, with three modes.

Fifth, it's sharp as hell and has chromatic aberration compensation and rectilinear barrel distortion compensation.

It's a really, really nice lens. It's just slow, is all.

[Ben_B]

I think you totally missunderstood what I was saying. It is great that the gh1 can change lenses and that indeed adds to it's versitility. I was merely meaning that using a prime lens requires a certain type of situation where as a zoom lens allows you to frame a shot in a more flexible way. This was why I compared the hmc to the gh1 with it's zoom lens rather than a 50mm 1.4 etc.

Agree with above poster that you've obviously never used prime lenses on a set before because they're very easily and quickly swappable and you should already have all your shots planned out anyway, and know exactly what lenses you'll be using for each of them. A

As for using them on a documentary or doing ENG or event shooting you don't need the shallowest DOF possible, in fact it would be somewhat of a liability, so there isn't really a need to use fast primes...the GH1 kit lens should do ok for that, but I wouldn't necessarily advocate the GH1 for this type of work anyway.

And what I said still stands, for the $2000 difference between the GH1 and the HMC-150 you bet your ass I can buy a zoom lens that will kick the crap out of the HMC's in terms of versatility, low light performance, and DOF. Oh wait, Barry just proved the Gh1's stock lens beats the HMC-150 in all of those categories but low light performance...but that's with the GH1 at 100 ISO. Whoops. :)

[studio1972]

It doesn't sound like you've ever shot with a prime lens in a video situation before. While what you say sounds fine in theory, in practice this is seldom the case. The vast majority of 35mm adapter and VDSLR user actually uses prime lenses and prefers them to zoom because they're cheaper, faster and lighter. It takes a few seconds to swap lenses on set. A high quality zoom lenses can easily cost you a grand or more where as for the same amount of money you can have a set of fast primes to cover that same range. You'll almost never find yourself in a situation where you say "Hm, I wish I have a 38mm lens instead of that 35mm"; it's easy enough to just move in or out a bit. That's why it doesn't make any sense to artificially limited the GH1 to a slower zoom lens when many GH1 users actually does use primes.

Also, you can adapt any lenses to the micro 4/3 mount, and there are fast zooms out there in the 2.8 range, so why not include those?

Firstly, I used to own a 35mm adapter and I obviously used prime lenses on it exactly for the reason of achieving shallow DOF.

Secondly, as it happens I know of an event videographer who was intending to buy the GH1 and use it with the stock lens to get shallow DOF shots. The thing that surprised me was that when you check it out they won't get much shallower DOF than with their 1/3 camera unless they put prime lenses on the GH1.

Given that Panasonic seems to force you to buy the stock lens with the camera, I would imagine that many users use it without buying other lenses, it's hard to know either way really isn't it.

The lens on the HMC has a 13x zoom range from 28mm to 367mm (you would need a lot of primes to cover that range, and they wouldn't all be cheap), the closest lens to that available on the GH1 (as far as I know) is the stock lens which only has a 10x zoom. These are the lenses that come with each camera so it seems quite fair to compare them, whilst acknowledging that you can attach different lenses to the GH1 if you like.

Of course the GH1 is cheaper, but there are many other features that the HMC has which the GH1 doesn't, such as motorised zoom, better manual controls, ND filters built in, better handling, ability to film 25p beyond the 4GB limit, professional audio connections, PH mode recording, ability to attach an electronic focus puller for smooth focus pulls without having to touch the camera.

That's not to say that the GH1 isn't a great camera, it will suit a lot of people just fine. In a way you get the best of both worlds by having a 10x zoom lens and the availability of primes if you need them.

[studio1972]

And what I said still stands, for the $2000 difference between the GH1 and the HMC-150 you bet your ass I can buy a zoom lens that will kick the crap out of the HMC's in terms of versatility, low light performance, and DOF.

The HMC lens is a 13x zoom 28 - 367mm f/1.6-3.0. Please back up your statement with a reference to the equivalent lens on the GH1 for less than $2000. If you had the faintest idea about the compromises involved with lens design you would realise it's much easier to make a lens like this for a 1/3 sensor than a 4/3 sensor.

[Barry_Green]

Of course the GH1 is cheaper, but there are many other features that the HMC has which the GH1 doesn't, such as motorised zoom, better manual controls, ND filters built in, better handling, ability to film 25p beyond the 4GB limit, professional audio connections, PH mode recording, ability to attach an electronic focus puller for smooth focus pulls without having to touch the camera.
And way better ergonomics, and live monitoring, and manual audio level control, and phantom power for microphones, and zoom mm readouts and focus distance readouts, and on and on and on. And, not the least of which, a fully professional codec that will never mud-out on you. For video purposes the HMC150 is a way better camera. The GH1 can make sharper, smoother, shallower DOF images, but for actually USING the product, the 150 is a "real" video camera.

There's no getting around the notion that the GH1 is a stills camera with a video mode, whereas the HMC150 is a professional video camera sold and supported by the broadcast division of Panasonic.

(one correction; the GH1 isn't limited to 4GB, it can record for the full duration of the SD card. It's the Canons that can't go past 4GB).


That's not to say that the GH1 isn't a great camera, it will suit a lot of people just fine. In a way you get the best of both worlds by having a 10x zoom lens and the availability of primes if you need them.
Definitely, but there are lots of reasons why I have both!

[studio1972]

(one correction; the GH1 isn't limited to 4GB, it can record for the full duration of the SD card. It's the Canons that can't go past 4GB).

I'd heard somewhere that this was a limitation on the UK (25p) version but not the NTSC version, I might be wrong though, and I would imagine if anybody knows, you do.:beer:

[Martti Ekstrand]

As there's some silly EU import tax that kicks in on video cameras that can record for more that 30 minutes there's a artificial 29:59 recording limit on the GH1 PAL cameras delivered to EU. The Hongkong PAL version does not have this limit.

http://philipbloom.co.uk/2009/06/03/the-lumix-30-minutes-eu-recording-issue/

[Barry_Green]

Doh! You are correct, there is an artificial limit imposed because of the EU. Sorry, should have thought that one through.

[Jack Daniel Stanley]

...I was merely meaning that using a prime lens requires a certain type of situation where as a zoom lens allows you to frame a shot in a more flexible way...
And a less sophisticated way; If you're just zooming to reframe your shot you doing videography, not cinematography.

Maybe you just mean you don't have to swap lenses?

But each focal length affects many things about the image such as the relative distance from one object or actor to another object or actor. Cinematography is about making decisions like that. Maybe the characters should seem distant from one another, maybe they should seem very close. If you're just zooming in without moving the sticks to change the frame without considering not only the frame but the spatial relationships and DOF that's right for the story telling then you're not telling the story visually.

Now you can do that with a zoom lens - pick focal lengths and apertures that help tell the story in conjunction with moving the sticks for the framing - but it sounds like you just wan to zoom in for your closeup like soooooo many people do when shooting bare lens with a video camera.

With a DSLR changing lenses takes only a little longer than taking the lens cap off and on the HMC 150.

[Ben_B]

The HMC lens is a 13x zoom 28 - 367mm f/1.6-3.0. Please back up your statement with a reference to the equivalent lens on the GH1 for less than $2000. If you had the faintest idea about the compromises involved with lens design you would realise it's much easier to make a lens like this for a 1/3 sensor than a 4/3 sensor.

Ok so I'll get 2 zooms for $1,000 each :D

[Ben_B]

and a less sophisticated way; if you're just zooming to reframe your shot you doing videography, not cinematography.

Maybe you just mean you don't have to swap lenses?

But each focal length affects many things about the image such as the relative distance from one object or actor to another object or actor. Cinematography is about making decisions like that. Maybe the characters should seem distant from one another, maybe they should seem very close. If you're just zooming in without moving the sticks to change the frame without considering not only the frame but the spatial relationships and dof that's right for the story telling then you're not telling the story visually.

Now you can do that with a zoom lens - pick focal lengths and apertures that help tell the story in conjunction with moving the sticks for the framing - but it sounds like you just wan to zoom in for your closeup like soooooo many people do when shooting bare lens with a video camera.

With a dslr changing lenses takes only a little longer than taking the lens cap off and on the hmc 150.

yes!

[Ben_B]

the notion that the GH1 is a stills camera with a video mode, whereas the HMC150 is a professional video camera sold and supported by the broadcast division of Panasonic.


I am starting to think of it more as a consumer video camera (which have been getting better and better and better images...just with fewer features than prosumer cameras) with the ability to take interchangeable lenses, focus manually, etc....that also has a gimmicky photo mode that nobody should really use :D

[studio1972]

And a less sophisticated way; If you're just zooming to reframe your shot you doing videography, not cinematography.

I am a videographer filming events, never claimed to be anything else, check out my sig :beer:

[Ben_B]

Great. The GH1 isn't for you. Don't buy one.

It's an amazing camera for those of us doing narrative filmmaking.

What I see it doing for a wedding videographer would be that you could leave your HMC setup as a (relatively...you could come back to it and zoom in, tweak framing, etc, as long as you know you have coverage to put over it from the other camera) static camera and then use the GH1 to get a wide variety of very lovely, shallow DOF shots, and cut back and forth.

[Huy Vu]

The HMC lens is a 13x zoom 28 - 367mm f/1.6-3.0. Please back up your statement with a reference to the equivalent lens on the GH1 for less than $2000. If you had the faintest idea about the compromises involved with lens design you would realise it's much easier to make a lens like this for a 1/3 sensor than a 4/3 sensor.

You can pick up 2 of the Nikon 28-70mm f2.8 and the 70-200mm f2.8 for roughly that amount. And those lenses were made for FF35mm sensor so yea, I'll say it's more than good enough.

Btw, that's not the actual focal length of the HMC, just the FOV equivalent. Actual focal length is more like 3.6 mm at the wide end and 47mm on the telephoto end.

[Barry_Green]

Ben, don't be rude please.

The GH1 may or may not be applicable to Stuart's business. Shallow-DOF gorgeousness could be extremely applicable to wedding videography. As I understand, the 5D Mark II has caught on with wedding videographers; the GH1 is a lot easier to use than the 5DM2 and therefore might be a lot more applicable.

I don't know that I'd want to use it as my sole video camera for such an event, but there's definitely a place for something like it.

[Barry_Green]

Btw, that's not the actual focal length of the HMC, just the FOV equivalent. Actual focal length is more like 3.6 mm at the wide end and 47mm on the telephoto end.
3.9mm wide, 51mm tele.

[Jack Daniel Stanley]

... As I understand, the 5D Mark II has caught on with wedding videographers; the GH1 is a lot easier to use than the 5DM2 and therefore might be a lot more applicable...
It seems like the 5D just has some predictable skew issues though as opposed to randomly puking every now and then. Somewhat acceptable when you can do a retake, but I wouldn't trust it as my only cam in a doc situation like a wedding. Additional, as Ben suggested, but doc / videography, no. Next gen or post firmware upgrade yest. But right now no.

[studio1972]

Great. The GH1 isn't for you. Don't buy one.

It's an amazing camera for those of us doing narrative filmmaking.

What I see it doing for a wedding videographer would be that you could leave your HMC setup as a (relatively...you could come back to it and zoom in, tweak framing, etc, as long as you know you have coverage to put over it from the other camera) static camera and then use the GH1 to get a wide variety of very lovely, shallow DOF shots, and cut back and forth.

I think that is exactly what I could use it for. However, I know a very top end wedding videographer in the UK who was planning to get a GH1 for this purpose and was intending to use it with the stock lens. I think we can all agree that they would need to use faster lenses (primes) to get the shallow DoF.

This can be a bit of a hassle in an event situation as by the time you've attached the right lens, ND filter etc. and moved your sticks, the thing you wanted to film has gone away. This would obviously be less of a problem if you have two operators though as one can get the safe shots with the HMC while the other goes for the more interesting stuff with the GH1 and primes.

It's a shame they don't sell the GH1 without the stock lens though as this would make it a lot more affordable if you don't intend to use that lens. These VDSLRs seem to be getting better and cheaper all the time though, so I think I'll see how it goes and just get shallow DOF using the usual trick of zooming in for the time being.

[Ben_B]

Ben, don't be rude please.

Sorry. I'm just getting a little annoyed with people, not necessarily in this thread, but across all threads, going after this camera because Panasonic didn't design it with exactly them in mind. It doesn't help that I am one of the people for whom this camera fits perfectly, and I really don't like coming in and reading people bashing it, claiming that because it doesn't work for them that all footage shot with it must be worthless, for the web, for broadcast, for theatrical presentation, whatever (again not so much in this tread but overall.)

[studio1972]

You can pick up 2 of the Nikon 28-70mm f2.8 and the 70-200mm f2.8 for roughly that amount. And those lenses were made for FF35mm sensor so yea, I'll say it's more than good enough.

Btw, that's not the actual focal length of the HMC, just the FOV equivalent. Actual focal length is more like 3.6 mm at the wide end and 47mm on the telephoto end.

2 zooms isn't the same as 1 zoom though is it. It's much easier to design 2 lenses with a 3x zoom than one with a 10x zoom. That's why Nikon don't make a 20-200 f/2.8 zoom.

I knew the actual focus length on the HMC was different btw, I own one and it has the numbers printed by the zoom ring for me. I used the 35mm equivalent numbers to make it easier to understand what the zoom range of the lens is in practical terms. The HMC has a crop factor of roughly 7.21 if you're interested. If you look at the first post in this thread this is quite clear.

[studio1972]

Sorry. I'm just getting a little annoyed with people, not necessarily in this thread, but across all threads, going after this camera because Panasonic didn't design it with exactly them in mind. It doesn't help that I am one of the people for whom this camera fits perfectly, and I really don't like coming in and reading people bashing it, claiming that because it doesn't work for them that all footage shot with it must be worthless, for the web, for broadcast, for theatrical presentation, whatever (again not so much in this tread but overall.)

Well I'm sorry that I annoyed you (assuming that I did), but I don't think I was bashing the camera at all. I actually said a lot of positive things about it.

I was just making a point that with the stock lens the DOF isn't that much shallower than a 1/3 camera, I also said that "Obviously the results would be different with prime lenses etc.". I said that in the first paragraph of the first post in this thread and ever since then people have been having a go at me as if I had said the opposite of that.

[Barry_Green]

Well, it's still not an accurate statement though.

With the stock lens, set to the same aperture as the 1/3" camera, the GH1 will slay. You have to go about 3 stops more open before the 1/3" camera can start to catch up.

[Jack Daniel Stanley]

...I was just making a point that with the stock lens the DOF isn't that much shallower than a 1/3 camera...
except that it is


http://dvxuser.com/barry/Straw-Combined.jpg


you can get shallow DOF with a 1/3 chip camera by zooming all the way in and standing on the other side of the park (Barry showed us how to do that in 2004 on the DVX) but it's not comparable to what you can get with the GH1 even with the stock lens.

[Ben_B]

Well, it's still not an accurate statement though.
With the stock lens, set to the same aperture as the 1/3" camera, the GH1 will slay. You have to go about 3 stops more open before the 1/3" camera can start to catch up.

You're darn tootin'.

[Barry_Green]

I might put Straw Man in a low-light condition to see how they perform with both cameras wide-angle and wide-open...

[Ben_B]

Light the straw man like he's in a film noir and see if you can get dramatic lighting without banding.

[studio1972]

Well, it's still not an accurate statement though.

With the stock lens, set to the same aperture as the 1/3" camera, the GH1 will slay. You have to go about 3 stops more open before the 1/3" camera can start to catch up.

But the stock lens isn't capable of the same aperture as the hmc lens. Bit silly to restrict the hmc to f/4 and narrower when you would obviously open it up and apply nd filters to achieve shallow dof. I think that's a bit disingenuous to be honest. Now we are going round in circles though.

[Jack Daniel Stanley]

... silly to restrict the hmc to f/4 and narrower when you would obviously open it up and apply nd filters to achieve shallow dof. ...
No one's asking you to restrict it.

But the claim:

...with the stock lens the DOF isn't that much shallower than a 1/3 camera...
isn't accurate.

If I stand at the other end of the football field and zoom all the way in on a 150, 200, 170, EX1, jump up and down and stand on one leg, I can get SDOF too.

But the those cams at the same Fstop and focal length as the GH1 will have deeper DOF.

GH1 is a system that yields inherently shallower DOF without standing on your head. If the 150 was nearly equivalent there would be no 35mm adapter industry. In fact, why do you own one? The DOF is fairly equiv to the GH1. Since the DOF for a 150 is so simillar seems like it would not be worth having a DOF adapter.

[Martti Ekstrand]

I might put Straw Man in a low-light condition to see how they perform with both cameras wide-angle and wide-open...


Light the straw man like he's in a film noir and see if you can get dramatic lighting without banding.

Set him on fire, dance around singing and re-christian him to The Wicker Man. :violent5:

[studio1972]

No one's asking you to restrict it.

But the claim:

isn't accurate.

If I stand at the other end of the football field and zoom all the way in on a 150, 200, 170, EX1, jump up and down and stand on one leg, I can get SDOF too.

But the those cams at the same Fstop and focal length as the GH1 will have deeper DOF.

GH1 is a system that yields inherently shallower DOF without standing on your head. If the 150 was nearly equivalent there would be no 35mm adapter industry. In fact, why do you own one? The DOF is fairly equiv to the GH1. Since the DOF for a 150 is so simillar seems like it would not be worth having a DOF adapter.


I wouldn't say that opening up the aperture and flicking the nd filter switch is in any way akin to standing on your head. It's exactly what any person would do. You can attach a prime lens to an adapter or a GH1 to get much shallower DOF than the HMC or the GH1 + stock lens.

The GH1 gets slightly shallower DOF with the stock lens as you demonstrated with your straw man, but you need a prime lens for it to really stand apart.

You keep arguing against statements that I never made in the first place. This is quite annoying and doesn't do you any justice IMO.

[GMC]

If you are interested, I just posted a GH1 wedding video on vimeo:

http://www.vimeo.com/6421216

It was quick and dirty, all is handheld, with kit lens, no grading.

What you can see is the SDOF you get with the kit lens, even at f5.8.

best regards, Gunther

[Ben_B]

I would say that opening up the aperture and flicking the nd filter switch is in any way akin to standing on your head. It's exactly what any person would do. You can attach a prime lens to an adapter or a GH1 to get much shallower DOF than the HMC or the GH1 + stock lens.


Having to zoom all the way in with the HMC stock lens and still not getting shallow depth of field and then having to use a 35mm adapter and rail system is what I believe what he meant by standing on your head.

That picture does not exactly represent a slight edge, more of a substantial edge, especially given the differing apertures.

[studio1972]

If you are interested, I just posted a GH1 wedding video on vimeo:

http://www.vimeo.com/6421216

It was quick and dirty, all is handheld, with kit lens, no grading.

What you can see is the SDOF you get with the kit lens, even at f5.8.

best regards, Gunther

Thanks Gunther, nice footage btw. I have thrown some HMC clips up on vimeo for comparison:

http://www.vimeo.com/6423166

[GMC]

Thanks Gunther, nice footage btw. I have thrown some HMC clips up on vimeo for comparison:

http://www.vimeo.com/6423166


Always very interesting, those discussions - thanks for posting. In any case, its up to the shooter to get the best out of the cams. So all these technical discussions are a bit theoretical.

best regards, Gunther

[Barry_Green]

Y'know, I think this whole thing would have gone down better had it been about how slow the GH1 lens is, rather than on the DOF...

... because, seriously -- an HMC150, at 1.6 and full wide angle, might match the GH1 at 4.0. Fine. Very limited circumstance, but fine. At any other f-stop, the GH1 wins. 2.0 vs. 4.0? Gh1 wins. 2.8 vs. 4.0? Gh1 stomps. 4.0 vs. 4.0? Gh1 destroys. So you've got a very extremely limited window of where the HMC150 could potentially compete (assuming, of course, that shallow DOF is all that you're after).

But what if you want shallower? Well, there, you have to use something additional, an add-on product. With the HMC150, you're talking about a Letus Extreme or Brevis or Redrock rig, for another $2,000.

With the GH1 you're talking about a $50 lens off ebay.

So, I guess, put another way -- the GH1 can never be worse, and will almost always be better, and frequently will be substantially better in providing the shallow DOF look, and is capable of being astonishingly better.

[studio1972]

Y'know, I think this whole thing would have gone down better had it been about how slow the GH1 lens is, rather than on the DOF...

... because, seriously -- an HMC150, at 1.6 and full wide angle, might match the GH1 at 4.0. Fine. Very limited circumstance, but fine. At any other f-stop, the GH1 wins. 2.0 vs. 4.0? Gh1 wins. 2.8 vs. 4.0? Gh1 stomps. 4.0 vs. 4.0? Gh1 destroys. So you've got a very extremely limited window of where the HMC150 could potentially compete (assuming, of course, that shallow DOF is all that you're after).

But what if you want shallower? Well, there, you have to use something additional, an add-on product. With the HMC150, you're talking about a Letus Extreme or Brevis or Redrock rig, for another $2,000.

With the GH1 you're talking about a $50 lens off ebay.

So, I guess, put another way -- the GH1 can never be worse, and will almost always be better, and frequently will be substantially better in providing the shallow DOF look, and is capable of being astonishingly better.

Factually speaking that is pretty much what I said in the first place (admittedly spinned another way), 7 pages back. Thanks for the discourse though. :beer:

[Simon Höfer]

In defense of the Thread starter:

Before I bought the GH1 I exactly wanted to know what he tried to demonstrate. I wanted to know how shallow the DOF with the stock lens is. Because I didn't want to buy additional lenses in the next few months, because I primary wanted to use it for personal work, holiday and such.

I actually don't understand why everybody is so upset about him. He was just comparing the stock lens capabilities to other cameras. He didn't even want to bash the camera.

So lets all be friends now and play with our awesome GH1 cameras :D