HVX Resolving lens power?

[Darkline]

Hi All

I hear a lot on this and other forums about whether the HVX will have a lens good enough to resolve a true HD signal. Many people say that there is no point in having higher resolution CCD's as the lens could not resolve that much information.

So my question is this, why does my $50 lens on my canon DSLR seem to have the resolving power good enough for 8Mpixels? One look at the produced images would confirm that the lens is indeed up to the task.

My guess is that the lens on the HVX will make up a fair chunk of the price of the camera; and as it's non-interchangable Panasonic are obviously playing the 'mass production = reduced costs' card on this. So we should be getting better quality glass than on my $50 canon lens.

Is it down to the CCD size in turn making a big difference to the lens production?
Is it to do with the degredation of having a powerful zoom?

I have a zoom lens for the canon which doesnt seem to sacrafice image quality too much (still very nice 8Mpixel images).Even my pocket sized Optio S with a lens on the size of a dime seems to resolve extremely high images of 4Mpixel (all beit with lovely barrel distortion too)

Thanks for any enlightenment! I just dont get it, wouldn't the lens on the HVX be vastly superior to all of these and good enough for 2Mpixel and beyond? :huh:

 

[Nathan_Rodger]

Hi mate,
Firstly - your $50 (18-55 I'm assuming) actually doesn't have enoug power to resolve 8mp - if you get an L grade lens or even the 50mm 1.8 or 1.4 and compare like for like on detailed shots... its very EASY to see the difference between the two. photo.net has an article about this exact comparison I think, but the stock lens - cannot resolve the 8mp that the 20D or 350D has to offer....

Again it depends how big you print, and what your end use of the pictures is - but the stock lens is about $50 for a reason.... They make it to a price...
Now if thats a 50mm lens off ebay - then theres your answer - a) its a prime lens - easier to make good glass when you have less elements to play with. Also much easier to make good elements when they don't have to move for zooming.

When you go to zoom lenses in the L range (read the bread and butter lens 70-200mm 2.8L IS USM) the reason that so many photogs love this lens (me inlcuded) is that it has the resolving power at ALL focal lengths to be able to produce truly magical images. Sharp as a tack and the contrast and clarity of image is VERY hard to beat. It is very close to being on par with many primes through the focal range it has. This is an expensive lens... for a reason...

Will the HVX have a true HD resolving lens? I will hazard a guess to say it will - Panasonic will have the fabulous team at Leica make a lovely lens that will resolve VERY nicely I'm hoping.... If it doesn't - which I doubt - that would be truly dissapointing...


Cheers, Nathan.

 

[Darkline]

the lens i have is a 50mm prime off ebay

the explaination of prime over zoom does go some way to answering the question, but it still leaves me confused. The 350D with it's stock zoom lens still produces fabulous images which resolve at a great Mpixel - perhaps not 8 - but pretty close.

Also the 50$ 50mm lens is resolving at a level four times greater than the HVX needs to. The HVX should have far better glass than this. Even factoring the zoom, it still doesnt make much sense that it should even be an issue for the HVX.

lets take the dime sized zoom lens on my pocket optio S. I get a 4MP image out of this. The argument being that it cannot resolve the full 4MPixel from such a small lens? Well i would certainly notice the difference between a 4Mpixel capture from it and a 720x576 image resized to 4Mpixel. The difference is huge - so it must be resolving much greater than SD even on a pocket size cheap digicam.

Inferior zoom lenses on digital still cameras seem to be able to resolve higher than that for next to nothing.... Unless all the digicams people have are no use beyond SD, and we've all been fooled into buying higher Mpixel cams that dont deliver any increase in resolution at all.

Cased in point - Reelstream. This uses pixelshft to get a HD image out of the Existing DVX and it's fixed lens. I believe they are extracting images around 1500pixels wide from it, and the results I have seen look pretty convincing. Is everyone saying this is pointless becasue the lens cannot resolve greater than SD?

Im not saying all this talk of "you cant have higher CCD's beacuse the lens is the limiting facotr' is rubbish. I'd just like to see some evidence that backs its up. The old DVX lens seems capable enough of resolving a HD image and the HVX should have better glaas than that. It wouldn't suprise me if the lens could resolve 3/4Mpixels.

but i would like to add I know nothing about lenses! :laugh:

 

[Neopics]

Is it down to the CCD size in turn making a big difference to the lens production?

Bingo...you hit the nail on the head right there.

Two things in particular make this distinction important. Resolving power and focal length.

Any given lens will have a particular sharpness or resolving power regardless what size sensor is picking up that image. An SLR lens can get by with a relatively ordinary level of sharpness because it's image is being formed over a fairly large sensor area, well over an inch diagonally. But if you used that same lens over 1/3" high resolution CCDs, as used in the HVX200, you would begin to see its deficiencies. Only a very expensive SLR lens would have the necessary resolving power for an image that size.

Then comes the focal length. The above example would also give you less shooting coverage. 50mm is a fairly medium-wide angle lens on an SLR, but a significantly narrow lens on a 1/3" sensor. In order to get the same relative coverage, the HVX200 needs a much shorter focal length range. This in turn makes it much more challenging to manufacture -- short lenses are harder to make than long ones. That is why really good wide angle lenses tend to be expensive.

 

[Darkline]

thanks for the explaination. it seems like the 1/3 inch ccd's not only limited dynamic range and resolution but also a domino effect in the entire manfacturing chain that makes image pick-up difficult.

in the long run wouldnt it be cheaper to have 2/3 ccd's

what size CCD's are there in the average pocket size digicam then? much bigger than 1/3 inch?

 

[baro]

Rather than a DSLR with a prime lens, a much better example for that digital still camera lens argument is the 5 Mpixel Panasonic DMC-FZ5. It's CCD size is very close to the size of the CCDs in the HVX (1/2.5") and it has a 12x zoom lens. The whole camera is about $320 new and it received very good reviews for the sharpness of its lens.

One review with sample images is at: http://www.dpreview.com/reviews/panasonicfz5/

 

[taubkin]

Rather than a DSLR with a prime lens, a much better example for that digital still camera lens argument is the 5 Mpixel Panasonic DMC-FZ5. It's CCD size is very close to the size of the CCDs in the HVX (1/2.5") and it has a 12x zoom lens. The whole camera is about $320 new and it received very good reviews for the sharpness of its lens.

One review with sample images is at: http://www.dpreview.com/reviews/panasonicfz5/

that's a Leica lens built in. Nobody makes lenses like Leica. Panasonic made a very wise choice in teaming up with them, and is now producing some of the top image making electronics availilable. Their lumix cameras are clones of the Digital Leicas, and are always very impressive, even the cheap models as this. In the end, you can have a suit bought at walmart or an Armani. It's not JUST the brand thing, but the guys at Armani can make better looking suits, we might not know why, but we can see the difference...

 

[stabwound]

Any given lens will have a particular sharpness or resolving power regardless what size sensor is picking up that image. An SLR lens can get by with a relatively ordinary level of sharpness because it's image is being formed over a fairly large sensor area, well over an inch diagonally. But if you used that same lens over 1/3" high resolution CCDs, as used in the HVX200, you would begin to see its deficiencies. Only a very expensive SLR lens would have the necessary resolving power for an image that size.

That is true.

In the still photo world, it is generally acknowleged that the less you need to blow up a medium, the sharper the picture.

An 8x10 camera needs no blowing up to make a 8x10 photo. The requirements for a good lens is much less demanding than with a 35mm lens, where the 35mm format needs to be blown up several times to make a 8x10.

A 1/3 sensor would require an extremely sharp lens to make an adequate picture.... because it will blown up even more.

If you checked the photode lens ratings, the best medium format lenses, even the Hasselblads, don't score as high as the best 35mm lenses. They don't have to, to get a great picture.

 

[Barry_Green]

... and then think of what's being asked for from these cameras. People want to use a 1/3" sensor, which is about 5mm x 3mm, and blow that image up to a movie screen! We talk about using a 35mm SLR to make a 5x7" print, or maybe an 8x10", but when you start looking at making 11x14" prints or more, pepole start looking for medium format or bigger cameras. But for theatrical presentation we're trying to blow up a 5mm x 3mm sensor to dimensions of maybe 30 feet x 20 feet! It's nutty! And yes, the lens requirements are extraordinarily tight for a 1/3" high-def camera.

 

[Adamsenoj]

A 1/3 sensor would require an extremely sharp lens to make an adequate picture....

And yes, the lens requirements are extraordinarily tight for a 1/3" high-def camera.

I keep hearing about how a 1/3“ CCD calls for more strict specifications for a lens and how a HD lens for a 1/3“ camera is very hard to design etc. People also say a lens made for a film camera will not work properly with a CCD camera and that if it’s a 3 CCD, you can forget it, because the prism will make it even less comparable and all that. But the real world experience is totally different. There are just so many people out there getting great results with 35mm still photography lenses mounted in 3 CCD cameras. I have seen gorgeous stuff, with zero aberration, shot with a Canon XL2 and 35mm lenses, just by using a simple F or FD mount adapter. It looked better than anything shot wit any XL lens, which were specially developed for 1/3” 3 CCDs.
Then there’s the P+S Tecnik Mini-35 for the XL2, which uses a connecting lens that is most likely not made for 1/3” CCD and specially not for 3 CCDs, and it looks gorgeous. Now the Mini-35 even works with the HD100, which is a HD camera, and the connector lens is the very same as the XL2. Is this lens made for a 3 CCD 1/3” HD camera? Hardly. As I said, I have seen both and I’m sure they are the very same lens, just with a different mount. All that seems to be just geek talk and really doesn’t represent anything in the real world. I think if the lens is sharp enough, it doesn’t really mater if it’s for a 1/3”, 2/3” or 35mm, it will look good.

 

[Neopics]

in the long run wouldnt it be cheaper to have 2/3 ccd's

Wouldn't that be nice. :thumbsup: What works against that idea is that they also have to output all that data at an extraordinary speed, bringing the cost back up again.

what size CCD's are there in the average pocket size digicam then? much bigger than 1/3 inch?

Usually not, but then there are other factors in play. The lens diameter on these cameras is usually quite small, which results in a slower lens (less light gets through). And, they often have a very limited zoom range (3x or 4x at most, usually). Both of these factors make them less expensive to manufacture.

Granted, there are some really good pocket digicams now. I'm certain most of their cost -- which is usually higher than average -- is going toward a better quality lens.

 

[Neopics]

There are just so many people out there getting great results with 35mm still photography lenses mounted in 3 CCD cameras. I have seen gorgeous stuff, with zero aberration, shot with a Canon XL2 and 35mm lenses, just by using a simple F or FD mount adapter.

This is definitely true, but most of the time these are extremely telephoto shots with higher-end SLR lenses.

Then there’s the P+S Tecnik Mini-35 for the XL2, which uses a connecting lens that is most likely not made for 1/3” CCD and specially not for 3 CCDs, and it looks gorgeous.

Ah yes, but the whole point of the Mini-35 is that it forms an image on a ground glass screen at the same size as a 35mm frame. That way, the full resolution of the taking lens is utilized at a size much larger than 1/3" diagonal. Then, a relay lens inside the adapter -- a very high quality one that is definitely made for smaller CCDs -- reduces the image down to the camera's native sensor size.

 

[stabwound]

There are just so many people out there getting great results with 35mm still photography lenses mounted in 3 CCD cameras. I have seen gorgeous stuff, with zero aberration, shot with a Canon XL2 and 35mm lenses, just by using a simple F or FD mount adapter.

They might be getting great results with 35mm lenses, but their usefulness while mounted on a 1/3 sensor is pretty limited.

The best 35mm lenses are usually primes. Example: the 50mm 1.4 Canon will give a great picture, but I'm sure it's a pain to change lenses for every shot. The 50mm also becomes a tele when mounted on a 1/3 sensor camera due to the crop factor...

If you need a wide angle, you're out of luck. Even a 35mm lens (15mm) that is considered super wide, when mounted on a 1/3 sensor will not give you wide angle due to the crop factor. I sure haven't seen a 35mm 4.5mm lens anywhere.

The 13 times, wide angle to tele, aperature f1.6 (?? I can't seem to find the exact spec) zoom lens of the HVX200 has no equivalent in the in the 35mm world.

If someone were to make a 35mm zoom that matched the specs of the HVX200, it would probably weigh a ton, be big as my suitcase and be expensive as hell.

I've stuck myself on a limb with the above statements. I'll be happy if someone proved me wrong...

 

[Benton]

Interesting,
Look at the examples section in the discussion forums here and look at some of the Beautiful test footage with the Guerilla35
http://www.guerilla35.com/

I am very interested in what people here have to say about this,
I am just going on the shallow DepthofField, which I Love,
But my knowledge of this is lacking and I really appreciate this discussion

 

[Darkline]

We talk about using a 35mm SLR to make a 5x7" print, or maybe an 8x10", but when you start looking at making 11x14" prints or more, pepole start looking for medium format or bigger cameras. But for theatrical presentation we're trying to blow up a 5mm x 3mm sensor to dimensions of maybe 30 feet x 20 feet! .

Persistence of vision fools the eye. An SD image viewed on a monitor in photoshop looks pretty awful - but view that same image at 25fps and suddenly we're all fooled and it 'appears' to look better quality.

We seem to be able to tolerate lower quiality images from a moving sequence than from a still. The brain doesnt analyise movies in the same way as it would a photograph or print. (well, everyone on this site is an exception to that :happy: ) Generally speaking, a film will be judged on its 90 minute duration, so image clarity isnt the primary concern of movie makers as each image is not indivudually scrutinized as a photograph would be... nice tho it is to have the best we can..

Thanks for all the replies I think the question has been answered quite well. Maybe someone will make a prosumer cam one day that doesnt come with a lens but a built in 35mm adapter. I understand the reservation tho, as it's limited with focal length.

Personally I would gladly sacrafice some loss in resolution to convery more of a mood or visual direction to a shot. Ever since I bought my DSLR my photo's have taken on a whole new look and it would be great to carry that over to my videos too.

As we're on the subject of the 35mm adapters, is there a review or comparison of the different models anywhere? I guess we wont know what effect they will have on the HVX resolution until some time mid next year. But if we're saying that the Leica lens will be just 'good enough' to resolve 2K, then I dont like the idea of going through multiple glass too.

 

[Adamsenoj]

This is definitely true, but most of the time these are extremely telephoto shots with higher-end SLR lenses...

Ah yes, but the whole point of the Mini-35 is that it forms an image on a ground glass screen at the same size as a 35mm frame. That way, the full resolution of the taking lens is utilized at a size much larger than 1/3" diagonal. Then, a relay lens inside the adapter -- a very high quality one that is definitely made for smaller CCDs -- reduces the image down to the camera's native sensor size.

Not really only zooms or telephoto only. The stuff I have seen was done with still primes.

About the Mini-35, I was talking about the relay lens. I don't think it's made of smaller 3 CCDs, because P+S makes no lenses. They have to buy it from somebody and I have never seen a high quality prime made for 3 1/3" CCD cameras. Also, the HD100 Mini-35 uses the same lens, and I'm sure it's not really designed for 3 1/3" HD CCDs.
Another proof that the sensor size thing is just fantasy is that you can use B4 lenses with the XL1 and it looks also better than the XL lenses, which were designed for the small chips. I bet a B4 HD lens, with an adapter, would look better with the HD100 than it's original lens, which is supposedly designed for the small chips too. This is all just specification obsession. Reality proves otherwise.

 

[Neopics]

Not really only zooms or telephoto only. The stuff I have seen was done with still primes.

You can have a "telephoto" prime...that's dependent on the magnification. A 50mm prime on an SLR is medium-wide. A 50mm lens on a 1/3" cam is telephoto.

How many of these tests have you seen that use a 4.5mm prime lens? (Probably none.)

About the Mini-35, I was talking about the relay lens. I don't think it's made of smaller 3 CCDs, because P+S makes no lenses. They have to buy it from somebody and I have never seen a high quality prime made for 3 1/3" CCD cameras.

It's not a "prime" per se. It's actually more like a macro/close-up lens -- the kind you would use to take a full-frame picture of a coin or insect. Plus, it only has a fixed magnification factor and no iris, so it doesn't need to be as complex as a prime or zoom. The cost of this lens, whether they make it themselves or source it, is certainly going toward its quality.

Another proof that the sensor size thing is just fantasy is that you can use B4 lenses with the XL1 and it looks also better than the XL lenses...

Sure, you can use the B4 lenses directly on the XL1 or HD100 with a simple adapter, but then you'll be limited to longer focal lengths. No wide angle stuff. And, you will not be taking advantage of the full resolving power of that lens. It may look pretty darn good, but not as good as if you used the Mini35 for your adapter, which forms the image at a 35mm frame size before reducing it down.

Ironically, Adamsenoj, the purpose of the Mini35 actually backs up everything I've been trying to explain, but you don't seem to undertand that.

 

[Neopics]

I bet a B4 HD lens, with an adapter, would look better with the HD100 than it's original lens...

I should also add... this would be a very expensive lens, which once again backs up the entire point of this thread. (i.e. Why HD lenses for 1/3" CCDs are more complex/expensive than common SLR lenses.)

The B4 HD lens you mention would be considered a very high quality lens for a 1/3" camera. There's no reason you couldn't use it, and that backs up what you are trying to say. But it would also come with a much higher cost, which backs up what I've been trying to say.

 

[Adamsenoj]

You can have a "telephoto" prime...that's dependent on the magnification.

I guess I knew that bit of information. That’s why I said “Not really only zooms or telephoto only”, meaning they were not zoom or telephoto primes. I think they were 18mm and 24mm.That’s not really telephoto for a 1/3” camera.

It's not a "prime" per se.

I meant prime, because it’s a fixed focal lens.

It's actually more like a macro/close-up lens -- the kind you would use to take a full-frame picture of a coin or insect.

How come people are using 35mm still lenses as relay lenses for their home built Mini-35 then? It works the same way.

Plus, it only has a fixed magnification factor and no iris,

Now you are dead wrong! The Mini-35 relay lens does have a iris. Instead of F-stops, it has steps from 1 to 7. But it has an iris. Have you ever even seen or touched one? I know you never used one, since I couldn’t see how you would use it without the iris, as you don’t know it has one.

so it doesn't need to be as complex as a prime or zoom.

It’s just a lens, as complex as any prime, with an iris ring, a focus ring and all.

The cost of this lens, whether they make it themselves or source it, is certainly going toward its quality.

P+S doesn’t make lenses. They clearly buy the lens from somebody else and the cost goes to make a full lens, as you probably already know by now.

Sure, you can use the B4 lenses directly on the XL1 or HD100 with a simple adapter, but then you'll be limited to longer focal lengths.

The maginification is not that big from a 2/3” to a 1/3”. A 2/3” HD lens has an average wide end between 6.8 and 8mm. That’s still pretty much on the wide end of a 1/3”. It’s not even mid range yet. You also have HD zooms as wide as 4.5mm.

No wide angle stuff.

As you’ve seen, it can get pretty wide.

And, you will not be taking advantage of the full resolving power of that lens. It may look pretty darn good, but not as good as if you used the Mini35 for your adapter, which forms the image at a 35mm frame size before reducing it down.
Ironically, Adamsenoj, the purpose of the Mini35 actually backs up everything I've been trying to explain, but you don't seem to undertand that.

The one missing something here is you. It doesn’t matter what the taking lens captures to the ground glass. It matter how much of it the relay lens captures to the CCD and the Mini-35 relay lens is sure not designed and developed for a 3 CCD 1/3” HD camera. I'm actually almost sure that lens is a 16mm film lens or a lens designed for a 2/3" 1 CCD camera. It's sure a lens that existed already before and they just took it for their system. They might have done some work on the housing, erasing brands etc, but it's just a normal lens they picked with the right focal length for their application.

I should also add... this would be a very expensive lens, which once again backs up the entire point of this thread. (i.e. Why HD lenses for 1/3" CCDs are more complex/expensive than common SLR lenses.)

My point was that this talk that lenses made for bigger targets, as in bigger CCDs or film frames, don’t yield good results on cameras with smaller imagers. Did you jump in the discussion and missed my point?

The B4 HD lens you mention would be considered a very high quality lens for a 1/3" camera. There's no reason you couldn't use it, and that backs up what you are trying to say. But it would also come with a much higher cost, which backs up what I've been trying to say.

Not really. Cost is besides my point and always was. My point is that the talk a film or 2/3” lens won’t work for a camera with smaller imagers is bogus! That was my point from the beginning.

 

[Neopics]

Now you are dead wrong! The Mini-35 relay lens does have a iris. Instead of F-stops, it has steps from 1 to 7. But it has an iris. Have you ever even seen or touched one?

To be honest, I haven't -- not in person. You are right (I stand corrected, thank you) -- the relay lens for Canon does have an iris. It's the adapter for Panasonic/Sony that does not have an iris.

The one missing something here is you. It doesn’t matter what the taking lens captures to the ground glass. It matter how much of it the relay lens captures to the CCD and the Mini-35 relay lens is sure not designed and developed for a 3 CCD 1/3” HD camera. I'm actually almost sure that lens is a 16mm film lens or a lens designed for a 2/3" 1 CCD camera.

We really don't need to bicker over this. Neither of us really knows specifically what P+S Technik uses for the relay lens, so were both speculating. But for any of those sizes -- 1/3", 2/3" or 16mm -- it needs to be very high quality, and would be for the customer base to whom it's sold. (And we've both aknowledged that it's likely a substantial part of the cost of the adapter.)

My point was that this talk that lenses made for bigger targets, as in bigger CCDs or film frames, don’t yield good results on cameras with smaller imagers. Did you jump in the discussion and missed my point?

Actually, your initial point was trying to debunk why a HD lens for a 1/3" camera was so hard to design.

Let's clear everything up. I am not disputing with you that it is possible to use a 35mm, 2/3" or any other lens on a 3 CCD, 1/3" camera. There are some excellent lenses out there that will do a fantastic job.

But within that realm you will have some trade offs -- either you won't have access to wider focal lengths (like 3.5 to 4mm) or you will have to pay an extraordinary amount of money for them.

Cost was the original point of this thread, which is why Darkline asked...

...why does my $50 lens on my canon DSLR seem to have the resolving power good enough for 8Mpixels?

Despite your claim to the contrary, Adamsenoj, there are definitely reasons why 13x 4.2mm lenses for HD 1/3" CDDs are more expensive to manufacture than common 35mm lenses. That's all I've been trying to explain.