F55: F55 16-bit RAW latitude test - ah finally !

starcentral

starcentral

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This is way too good to stick and hide away in the footage/frame grabs section.

Here is EXACTLY what you can expect to do with RAW from the F5/F55. Anyone familiar with processing RAW stills from DSLR will not be phased by this clip - but be impressed it is being done with "video" and not a still.

P.S. Sam Morgan - this is what you/we are after...


https://vimeo.com/66561435
 
Yep this is an old video and shows real use of the power of raw - cant remember how they did it but it shows to my why the upgrade from an F3 is only worth it if you are going raw with the 5/55
 
I've been too lazy to try SR codec RGB 444 on the F55 but I'd place my bets on "no way".

For one, it's still only 10-bit and you're just not getting the infinite data levels in the highlights like you do when you shoot RAW. Remember that in fact log goes to great lengths at equalizing all the data available throughout the entire data range but in fact who exactly says this is desired or what is required to get a filmic look?

My latest conclusions go as far as to say that LOG in general is DESTRUCTIVE to highlight information and so it means that unless you shoot with linear gamma, you will never get this high level of latitude from highlights period.

Now what about F35, Alexa, or even D20/21 people will bark?

These cameras are entirely different because its very obvious that there is some tremendous color science and highlight smoothening happening in camera before the image is even encoded with ANY particular gamma. ie. REC709 from Alexa looks great, ie. 8-bit slog image from F35 looks great, etc..
 
Really this video is the only video that actually shows the proper power of the camera - it is so mis understood that I have seen no similar with alexa etc.

The more I research the Alexa the more the decent stuff (skyfall) seems to have been shot Arri Raw anyway - I think it is a myth that the top end stuff is shooting prores.

Id say 444 is creamier than 422, but you wont get that latitude and it is actually far more expensive per minute in terms of data than sony compressed raw.

S
 
That's a real good point Sam, the Alexa in ProRes is "fantastic" but quite certainly the higher end productions are being shot in ARRIRAW where there is more latitude available in post.
 
It's your money, but I have yet to see why you can't do that kind of stuff with log.

Log vs. Raw: The Simple Version, by Art Adams. Raw is all the rage, but should it be? Log gives us 99% of the benefit of a raw file in a grade but with much smaller files.

Tonal quality and dynamic range in digital cameras, by Norman Koren. Log is destructive to the highlights, like you said. It reduces the upper zones from the ridiculous hundreds or even thousands of shades to about 100 per zone or f-stop. But this doesn't matter because the human eye can't see beyond about 70 shades per zone. And the "destruction" that log brings about is what you want, because it redistributes those surplus shades to the starved darker zones, which have only 10 or 20 shades when you use linear instead of log. Log is kind of the Robin Hood of bit depth.
 
Can you post any demos of doing that sort of stunt with a log camera?

While one may not need the highlight info when it is seen bright you certainly need it when pulling it back.

I think there is a huge difference between 'dynamic range' and 'latitude' - the second is bending the file in post.

My tests of the F5 did not show it to have much latitude at all (SR444 and XAVCHD) - I tested it against the nikon D3 stills camera in raw and could do nothing really with the file compared to the D3 which could pull a window exactly as seen here.

S
 
The reason you can't get that level of detailed data information in log is simply because it's not there.

With linear gamma (as found on RED RAW and now Sony RAW) starting from the low tones with each stop of light the amount of data bits allocated are doubled. So with 16-bit you get 65,000 levels to work with but its all heavily biased towards the right, or the highlights.

If you were to visually represent how data is allocated throughout the entire tonal range with linear gamma (as found in RAW) it would look like this:
gamma_gradient.jpg


If you were to convert this to log it would look like this:
gradient_5bit.jpg


Quite obviously with log you no longer have that "infinite" amount of information as you did with linear gamma.

Here's another chart which shows how data is allocated with various logs from Canon, to the Sony,
original_zps5c845237.jpeg
 
I would love to have this camera.. Now all of this to finally arrive to a poor looking grading

starcentral said:
This is way too good to stick and hide away in the footage/frame grabs section.

Here is EXACTLY what you can expect to do with RAW from the F5/F55. Anyone familiar with processing RAW stills from DSLR will not be phased by this clip - but be impressed it is being done with "video" and not a still.

P.S. Sam Morgan - this is what you/we are after...


https://vimeo.com/66561435
Click to expand...
 
The shot is not graded it is normalised and the DR brought into control - this is where you start a grade, if you want one.
 
starcentral said:
Try this with a log originating image, it's impossible
Click to expand...

Ohhh, I get it. Sorry. I totally misinterpreted the video. I thought it started out overexposed to show the shadows, then the cameraman iris'd down, then they lifted the shadows.

But what really happened is that the cameraman never iris'd down. It was all done in post. Interesting . . .
 
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