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-   -   Ignorant 16x9 Question? (https://www.dvinfo.net/forum/panasonic-avccam-camcorders/488499-ignorant-16x9-question.html)

Mark David Williams December 10th, 2010 04:35 AM

Hope I'm reading this right and happy to be corrected as the camera sounds brilliant but the sensor should be just under 22mm along its diagonal applied to any aspect ratio and may line skip. Oh dear that takes out the possibilty of using my 16mm zeiss superspeed lenses and makes me think this is much inferior to my Sony EX1?

Graham Bernard December 10th, 2010 04:45 AM

Quote:

Originally Posted by Mark David Williams (Post 1596968)
Oh dear that takes out the possibilty of using my 16mm zeiss superspeed lenses and makes me think this is much inferior to my Sony EX1?

Hmmm? Should I know consider the SONY route?

Grazie

David Heath December 10th, 2010 05:11 AM

Quote:

Originally Posted by John Wiley (Post 1596918)
Is it 12.1 megapixels total? Or effective? If it's the effective number of pixels, then which pixels are thrown away? ie how is it cropped? What is the aspect ratio of the sensor? ........
As for how the image is read off the sensor - well, that's beyond my level of undrestanding ........

I don't think the precise no of pixels on the chip really matters a great deal, it's the ball park figure that's most important. It seems pretty certain that there will be "enough", and whether it's 12, 12.1 or 11 megapixels is pretty academic - they'd all potentially give better than 1080 HD resolution.

But it's the fact that the no is "around 12" that IS important, since it brings up the far bigger question of read out, and how it's being done. The best way would be to read all 12 million off every frame, then downconvert - but that is likely to cost in terms off complexity and power heat issues.

Hence it's far more likely to pixel skip as DSLRs do - only read a percentage of the pixels each frame. There should still be more than enough for 1080 resolution not to be compromised - but it will impact performance in other ways.
Quote:

And in the end, all that really matters is that the picture looks great!
Well, yes, and I'm fairly sure it will. But the question may be if there's better still?

As said in the previous post, a purpose designed chip is far more likely to have about 4 megapixels - but read them all out every frame. The big advantage that is likely to have over the AF100 is sensitivity, either being able to be used in lower light, or far better s/n ratio.

The indications seem to be that is what Sony have done for the F3 and it's as yet unnamed little brother. And that's why a lot of people are waiting to see how they turn out rather than jumping in with an AF100 order now.

John Wiley December 10th, 2010 07:29 AM

Quote:

Originally Posted by Mark David Williams (Post 1596968)
and makes me think this is much inferior to my Sony EX1?

How so?

Because it is too big to use certain lenses, it makes it inferior to a camera with much smaller chips? That's like saying becuase you can't use APS-C lenses on your 5DmkII, it's inferior to your compact camera!

The truth is they are made for different purposes. The EX1 will be a much better choice for certain scenarios while the AF100 will outshine it in others.

Mark David Williams December 10th, 2010 08:15 AM

As I explained inferior if the sensor is line skipping.

The needed bigger lenses is only an issue for me wanting to use my Zeiss 16mm primes My thinking has up till now been that if the sensor is 17mm x 13.5mm in a 4:3 shape then my Zeiss primes with diameters of 20mm for the 25mm 19mm for the 16mm and 17mm for the 12mm would be more or less covered especially if shooting for 2.35 But I can see now.

The sensor can be diferent sizes as it follows just under 22mm diagonal line for the aspect ratio used So undoubtably the sensor will be 16/9 and just under 22mm diagonal so you will need a minimum 22mm rear lens to fully cover this.

Also the Sony EX1 offers 10 bit out and a superb lens. Factor in the lens costs and the camera is significantly lots more money for a sensor that line skips.
Not trying to promote any camera as I really like the things the Panny can do Just that line skipping is a deal breaker for me.

Olof Ekbergh December 10th, 2010 08:20 AM

I read somewhere that 16mm film lenses are ok if longer than 30mm, shorter will definitely vignette.

Mark David Williams December 10th, 2010 09:06 AM

Olaf thats a generalisation. Many 16mm lenses are larger than they need to be.

Graham Bernard December 10th, 2010 09:13 AM

Quote:

Originally Posted by Mark David Williams (Post 1597016)
Just that line skipping is a deal breaker for me.

If this is the case, would you think that Panasonic would care to comment?

Grazie

Olof Ekbergh December 10th, 2010 09:41 AM

An easy way to find out is to use a Lumix gf1 (or similar M43 still camera) with an adapter to M43 take a photo with your lens and check for vignetting.

A good rental house may be able to help you test this w/o purchasing.

Mark David Williams December 10th, 2010 09:49 AM

The problem appears to be the sensor size may be different for a stills camera to this one. At this point who knows.

The lack of a reply from Panasonic might indicate that line skipping is indeed used in the sensor.

Olof Ekbergh December 10th, 2010 10:10 AM

I believe the only difference from the still version is that it is cropped to 16:9. The lumix can even be set to shoot stills in this aspect.

So this would give you a very good idea if your lens will cover the sensor. It certainly is not a larger sensor than the standard 4/3.

Mark David Williams December 10th, 2010 11:35 AM

I personally doubt its the same sensor cropped. Just my opinion but I think it most likely sticks to the four thirds spec with a diagonal of just under 22mm that's usable this would make the camcorders sensor wider than the still camera sensor.

Best

Mark

Olof Ekbergh December 10th, 2010 01:10 PM

I just meant that the M43 spec sensor is the same size.

I am real sure the it is not the same sensor as well.

Personally I am using the Novoflex Canon FL/FD adapter to test 7 old lenses I have kicking around in preparation for the arrival of my AF100.

The 35mm f2 and 24mm f2.8 are very nice as is the old 50 f1.4. I did also order the Voigtlander 25mm f.95, it should be here soon. It is nice to compare the different lenses at 12 Mpx RAW in Aperture and PSD.

Guy McLoughlin December 10th, 2010 02:00 PM

Quote:

Originally Posted by Mark David Williams (Post 1597016)
As I explained inferior if the sensor is line skipping.

My understanding is that the AF-100 sensor does not perform line-skipping, though I've never been able to find technical details about how the sensor functions.

Recent production comments from cinematographers shooting with the AF-100 indicate that the camera does not have any noticeable moire or aliasing visible, and that resolution appears to match the Sony EX-1/3 cameras. ( the cinematographer who made this comment owns an EX camera )

Quote:

Originally Posted by Mark David Williams (Post 1597016)
Also the Sony EX1 offers 10 bit out and a superb lens. Factor in the lens costs and the camera is significantly lots more money for a sensor that line skips.

AF-100 does not line-skip, and image quality appears to be comparable to the Sony EX-1/3 cameras. ( Yes it's 8-bit, but almost all prosumer cameras under $10K are 8-bit )

All that said, the AF-100 is not an ENG camera, and would likely not be a great match for run'n'gun ENG style work. ( Sony EX-1/3, Canon XF300/305, Panaonic HPX 370/170 cameras would be a much better solution )

David Heath December 10th, 2010 03:02 PM

Quote:

Originally Posted by Guy McLoughlin
AF-100 does not line-skip, and image quality appears to be comparable to the Sony EX-1/3 cameras.

Can I ask why you don't think it pixel skips? Do you have any evidence to back that up?

It's important to realise that whilst pixelskipping has got a very bad name, a lot of that is down more to the absence of any optical low-pass filter in DSLRs than pixelskipping itself. Add an OLPF, (which the AF100 does) and the worst of the moire etc issues will go away, pixelskipping or not. Absence of moire or aliasing is not by itself an indication of no pixel skipping - it's an indication of an OLPF.

Given an OLPF, the ADVANTAGE to pixel skipping in such a camera is reduced complexity, power consumption, heat problems etc if a chip of over 10 megapixel is being used. The DISADVANTAGE will be (mainly) lower sensitivity or a higher noise level, compared to reading the whole chip and downconverting.

For optimal results, you really want a chip of more like 4-6 megapixel, same physical size, but the lower pixel count meaning pixel skipping is unnecessary. In many ways, you may not be able to tell much immediate difference between such and what the AF100 is doing - but it is likely to be inherently much more sensitive.


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