AF-100 Wishlist/Suggestion Discussion Thread

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Jan_Crittenden said:
HD-SDI is a standard, and that is 4:2:2. Obviously written by someone that is truly clueless.

The Codec is 4:2:0 just like any Long GOP codec, but this is AVCHD which is a powerful codec that is vastly better than any of the MPG2s.
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HD-SDI is 4.2.2 and 24p within 60i psf, always. HD-SDI is never native 24p. That is the same situation as with the EX1/3. That's fine for the Nanoflash as it can remove pulldown automatically.

If the AF100 has HD-SDI or HDMI the Nanoflash is 'In Like Flint', and can make using the EX1/3 with the AF100 together a breeze since they would/could all come out of the nanoflash in whichever file format (interframe, QT, MXF, MPG) you want.

If the resolution and aliasing end up much improved I'll be looking at replacing my 7D to go with my EX1. (And I bought the 7D to replace my Brevis. LOL)

However, I thought at one point someone (Jan at the convention?) said HD-SDI wasn't going to happen on the AF100. Any word on that or HDMI?
 
dadoboy said:
He's not that far off. The difference for the same field of view / depth of field, would be similar to that between the 2/3" chip cameras and s35mm, around 2.5 stops I think.
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This would mean that the DP is simply offing the responsibility to supply light and optimize the performance of the camera. And the difference between them will still not be any closer. Lighting is key to getting good imagery, and a failure to do so is a failure.

Frankly checking 2/3s vs the 4/3"s capability it is still huge. Get the Depth of Field Calculator, PCAM, it is invaluable. It absolutely resolves this argument. 4/3's regardless of F-stop or T-stop will offer performance more similar to a 35mm image, in 3 or 4 perf 1.78 aspect ratio. 2/3s is roughly 1/3 the size.

So let's do this, F5.6 on 2/3", object is 16 feet away, comparing the 2/3" with a 50mm equivalent to a and F5.6 on a 4/3" 50mm equivalent, and the depth of field is 70'7" on the 2/3"s and 12'2" on the 4/3"s. If we take that to F8 then the 4/3"s is 13'7" to the 2/3"s at 115'1". I can run the calculation on the 1/2" imager, but I promise it doesn't get closer to the 4/3"s.

I hope this helps,

Jan
 
Otis Grapsas said:
The EX3 with an f1.6 lens has practically the same DOF to f4 on 4/3 in any calculator that does the math correctly. The EX1/EX3 with the bundled f1.9 zoom is not very far. On the attachment you can see a 50mm lens equivalent on some common sensor sizes, the scales are in meters and the COC is chosen for single pixel blur diameter (COC) on 1920x1080 output.
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Hi Otis, From the calculator that I am using, PCAM, the 1/2" at 1.6 would give a depth of field of 8.2 feet, and the 4/3" of 2.2 feet. But in this entire discussion everyone has said that 1.6 would not be a suitable F stop as it would be too fast. But that is neither here ot there as any of these all in one cameras(lens included with camera, like the EX1 or the HPX170) they all have a sweet spot for resolution and that is somewhere in the f5.6-F8 point. The resolution at wide open is very soft across the entire image.

Hope this helps,

Jan
 
Jan_Crittenden said:
So let's do this, F5.6 on 2/3", object is 16 feet away, comparing the 2/3" with a 50mm equivalent to a and F5.6 on a 4/3" 50mm equivalent, and the depth of field is 70'7" on the 2/3"s and 12'2" on the 4/3"s. If we take that to F8 then the 4/3"s is 13'7" to the 2/3"s at 115'1". I can run the calculation on the 1/2" imager, but I promise it doesn't get closer to the 4/3"s.

Jan
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Yes, but lens availability is important, we can't just compare theoretically at an aperture, we need to put real lenses in front of the cameras. f1.4 lenses are quite common on 2/3", you can get 8mm to 50mm and even zooms, even fisheye, all in F1.4. F1.4 on a full frame sensor exists only in 50mm I think. The wide angles are f2.8 to f4. Same for telephoto, there are no 200mm f1.4 lenses, they are usually 2.8 to f4. How can we ignore that?
 
Jan_Crittenden said:
Hi Otis, From the calculator that I am using, PCAM, the 1/2" at 1.6 would give a depth of field of 8.2 feet, and the 4/3" of 2.2 feet. But in this entire discussion everyone has said that 1.6 would not be a suitable F stop as it would be too fast. But that is neither here ot there as any of these all in one cameras(lens included with camera, like the EX1 or the HPX170) they all have a sweet spot for resolution and that is somewhere in the f5.6-F8 point. The resolution at wide open is very soft across the entire image.

Hope this helps,

Jan
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For f1.6 1/2" vs f4.0 4/3? The calculator has to be wrong. The error is probably in the COC calculation. If it has manual COC, try these values (for 1080p):

Full frame 0.01875
4/3 0.009375
2/3" 0.005
EX1 0.00375

Any multiple will do as long at the relation between these remains the same. For 1080p sharpness though, these are accurate.

Edit: The crop factors for calculating equivalent focal lenghts are:

FF 1.0
4/3" 2.0
2/3" 3.75
EX1 5.4
 
Jan_Crittenden said:
...they all have a sweet spot for resolution and that is somewhere in the f5.6-F8 point. The resolution at wide open is very soft across the entire image.
Jan
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Camcorders with small sensors have very small pixels, diffraction comes sooner. They can be sharp at large apertures, even their maximum aperture, and quite soft at small apertures.
 
Jan_Crittenden said:
Otis,

You should really take a look at the PCAM calculator, it is more accurate than anything you are posting here.
http://www.davideubank.com/Good_Focus/pCAM_for_iPhone.html


Laws of physics cannot be denied and the reality is that there is no way that you would be able to gain the same DoF on a 1/2" or a 2/3" chip set in comparison to 4/3" regardless of aperture.

Best regards,

Jan
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Jan, anything I'm posting here is completely accurate. I have worked with the DOF equations for many years and built calculators. The DOF equations are very simple and there is no dispute on what they output for a given input. You can match the DOF by changing aperture, you can prove this by solving the DOF equations. I'm presenting the accurate facts and nothing more. If you use a calculator that disagrees with what I'm posting on DOF, try asking the developer about the COC values he uses or if the calculations and its presets are accurate for 16:9 frames. There is a large number of DOF calculators that use incorrect COC values, copied from books or websites, or applied incorrectly using the COC model of film print on paper.
 
Otis Grapsas said:
The EX3 with an f1.6 lens has practically the same DOF to f4 on 4/3 in any calculator that does the math correctly. The EX1/EX3 with the bundled f1.9 zoom is not very far. On the attachment you can see a 50mm lens equivalent on some common sensor sizes, the scales are in meters and the COC is chosen for single pixel blur diameter (COC) on 1920x1080 output.
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Tell me the EX1 is gonna ever do what the GH1 kit does at 0:27 in this video...and if I recall it wasn't even wide open (f/5.8 for that shot) it was a notch or two higher...if we apply the sunny 16 rule I can probably figure out what it was...with a 3-stop ND, and a 1/60th shutter at ISO 100...yeah I am pretty sure I shot that at f/8. I have shot on the EX1 pretty extensively, and I know from experience that it can't achieve that shot.

In any case the point is relatively moot because you're not stuck using an f/4-5.8 lens on the AF-100...you can put whatever the heck you want on there. If a superzoom on 4/3rds at f/4 gives you the same performance as a super zoom on a standard sensor at f/1.9, in so far as DOF/lowlight is concerned, then heck, you're set there! There's the lens everyone was clamoring for...and look, it didn't need to be f/2! And if you want the really shallow DOF that a large sensor can afford you, just slap an f/1.2 or f/1.4 or f/1.8 prime on there and go to town.
 
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Ben_B said:


Tell me the EX1 is gonna ever do what the GH1 kit does at 0:27 in this video...and if I recall it wasn't even wide open (f/5.8 for that shot) it was a notch or two higher...if we apply the sunny 16 rule I can probably figure out what it was...with a 3-stop ND, and a 1/60th shutter at ISO 100...yeah I am pretty sure I shot that at f/8. I have shot on the EX1 pretty extensively, and I know from experience that it can't achieve that shot.
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We shouldn't even be discussing this, it is easy to prove by using the equations, it has been proven quite a few times with actual cameras and lenses.

The only way it will not match is if the required aperture of camera A is not available on camera B, which is certainly possible. The crop factor between the two is 2.7 if we believe the Sony published focal length equivalents and accept the 4/3 to be 18mm wide. A typical 1/2" would be 2.5x but lets forget that for a second, perhaps they crop a little.

So for f5.6 it is f2.1, and for f8 it is 3.0. If you can get the same angle of view on the EX1 zoom and these apertures are possible at that focal length, it will match. Your memory of using camcorder A, and your not so accurate memory on that shot on camcorder B is not going to change the DOF equations! You might be correct, but if you are correct the math will verify your findings.
 
Otis,

I am done with this discussion. You are simply incorrect, I have a crew of Local 600 guys/DITs that back up what I am saying here. The PCAM product is heavily used by the DITs here in the US, and perhaps elsewhere. There just simply is not no way to match the DoF from a 1/2" imager without going to something like a 35mm adapter.

That is all.

My best regards,

Jan
 
Was just wondering how this thread got into a discussion on DOF calculations.

Thought we were suggesting features for the cam.
 
David S. said:
Was just wondering how this thread got into a discussion on DOF calculations.
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Because some people have a tendency to talk about what they know or think they know rather than talking aout what may be the features of the new camera.

A lot of FUD going on. :cheesy:
 
I think it started with the impression that was being offered that the DoF would be the same. I couldn't help myself. I apologize. Anyhow, I actually think that this thread is so big and so huge and virtually every feature that could be thought of has been suggested more than once if not 20. Maybe we start a new thread?

Thanks David, and again, sorry.

Best,

jan
 
http://www.dofmaster.com/equations.html

It's only high school math. Evaluate the equations for large sensor (focal length, f number, c) and then for small sensor (focal length/crop, f number/crop, c/crop).

You will see the only difference is in a small factor on the denominator. Test with actual numbers and you will see this affects the result to 0.5% precision max and that's only because of the focus distance reference we use to derive the equations. The precision error of an f stop marking on a lens is 10x greater than that. Any correct calculator verifies this. There are no theories about this, only simple math. Case closed.
 
Otis,

I am cropping for a 1.78 on all fronts, and the f number can be close, but it does not vary the issue to any significant degree. Add to that the quality of the lenses available for the EX1 and its own issue of using the widest apertures, there is no real comparison. I am sorry.

Best,

Jan
 
Jan_Crittenden said:
Otis,

I am cropping for a 1.78 on all fronts, and the f number can be close, but it does not vary the issue to any significant degree. Add to that the quality of the lenses available for the EX1 and its own issue of using the widest apertures, there is no real comparison. I am sorry.

Best,

Jan
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I simply stated a fact, that the superzoom will not provide seriously shallow DOF. I never discussed lens quality on EX1 or anything else. I just put some information on the table, which is proven, easy to verify, covered by theory and practice. You don't have to question my credibility, my sources and my calculations or put me against 600 experts:) One should plan on purchasing some primes with the new camera in order to get dSLR DOF and good low light. That's all. Panasonic want to sell lenses, right?
 
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