8 1/2 STOPS - latitude color grading chart

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Darkline said:
If Red has 8 1/2 stops of Exposure lattitude, what does a HVX have, film, and the current crop of high end HD cams?
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Just for clarity I'm not saying that Red has 8 1/2 stops of Exposure latitude. 8 1/2 stops simply represented the range of images I downloaded from CML. If they had posted the F22 series I could have gone further. I should have been more clear on that.

Once again this was just a visual experiment and not a professional assessment (I'm not qualified for that). Similar camera examples can be found here for comparison:
http://www.cinematography.net/Pages%...comparison.htm

BTW: HVX would not even come close - very noisey in the blacks.

Props to Red and David for letting us have a peek at these - very unusual for a camera under development. My guess is that we'll see more latitude tests shot in a few of months as things get closer.
 
boothba, I read a post from another forum that might be an interest to the reader of this thread, and kind of agreed with you comment too:
'....I am a bit surprised that after a gain of 3 F-Stops I get an entirely white image.

I have a frame from DALSA that still shows image detail after a gain of 10 F-Stops and the SI frames I have still show image detail after 4 F-Stops of Gain.

What is striking is the absence of noise in the RED images - I wonder
if this has to do something with the lack of dynamic range.....'
 
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Dont judge the image range you see via thumnails on the Dalsa vs. the F950 latitude test on CML.. those thumbnails arn't an accurate representation of the comparison, the Dalsa ones have been pushed to reflect correct exposure, as soon as you download a frame you will understand.
 
Agreed, those tests are interesting but not certainly not difinitive. It would be great to see a professional independant comparision against Dal/Vip/900 /D20/Kodak/Fuj etc.

While Red seems to have closed the gap (and passed it in many ways) with 35 mm, it still responds like video, abet cleaner.

Film...expose for shadows, print for highlights.
Video...expose for highlights, print for shadows (sort of)

Although I'm impressed by how much Gain can be introduced while still maintaining sharp edges, I find the colour accuracy even more impressive.
 
Umm.... It's not video that you expose to the right, it's digital (in general) you expose to the right. Digital photographers grok this - they use their histogram to ensure they capture their highlights, and as they have a good SNR, you know the shadows will be ok.
 
Of course your quite right Graham, video (or jpeg for that matter?) RGB processing et al does do this doesn't it. I shoot quite a bit of RAW stills for kicks. But of course that's your specialty!

Silly me.

Donatello, I indicated that comparo in another thread "Whoops - I underexposed 4 stops!!!, but as RED was not there I hold it to be only partially usable as a test. Interesting, but only just. I feel the tests have to be done at the same time for controls sake.
 
Y.Goh said:
boothba, I read a post from another forum that might be an interest to the reader of this thread, and kind of agreed with you comment too:
'....I am a bit surprised that after a gain of 3 F-Stops I get an entirely white image.
'
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Hmmm... I would certainly NOT agree with that poster. I was able to extract a very decent image at three stops over as seen on the chart at the start of this thread. And that three stops over would become four over (or something) if the sensor was rated at ISO 320 - 400 as Jim has said.

Regarding Dalsa showing "image detail after a gain of 10 F-Stops" I've seen overexposed images hold onto the blacks loooonnnggg after the hightlights and mids are gone. Is that what is meant by "image detail"?
 
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boothba said:
Hmmm... I would certainly NOT agree with that poster. I was able to extract a very decent image at three stops over as seen on the chart at the start of this thread. And that three stops over would become four over (or something) if the sensor was rated at ASA 320 - 400 as Jim has said.

Regarding Dalsa showing "image detail after a gain of 10 F-Stops" I've seen overexposed images hold onto the blacks loooonnnggg after the hightlights and mids are gone. Is that what is meant by "image detail"?
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Hi,

The original poster is well respected on CML. I did not see anybody disputing what was said there.

Stephen
 
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Stephen Williams said:
The original poster is well respected on CML. I did not see anybody disputing what was said there.

FWIW if the sensor is rated at 400 asa, the 3 stops over at 200 asa becomes 2 stops over at 400 asa.

Stephen
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1.) Sorry, I don't know who actually said that (I am re-quoting Y.Goh above) but apparently the quote was "after a gain of 3 F-Stops I get an entirely white image." Well anyone can look at the original tiff and see that it is not entirely white. And with a color grade you can salvage all but the bright highlights. No disrespect to the respectable. I'm just using my eyes.

2.) Ya I butchered the ASA / ISO thing. For clarity here's Jim's original quote:

"David Stump determined that the Mysterium sensor is ISO 200, but he and many other experts will likely recommend shooting at ISO 320-400. That gives a ton of room for the highlights to survive and plenty of elbow room for a beautiful clean image."

:dankk2:
 
boothba said:
1.) Sorry, I don't know who actually said that (I am re-quoting Y.Goh above) but apparently the quote was "after a gain of 3 F-Stops I get an entirely white image." Well anyone can look at the original tiff and see that it is not entirely white. And with a color grade you can salvage all but the bright highlights. No disrespect to the respectable. I'm just using my eyes.

2.) Ya I butchered the ASA / ISO thing. For clarity here's Jim's original quote:

"David Stump determined that the Mysterium sensor is ISO 200, but he and many other experts will likely recommend shooting at ISO 320-400. That gives a ton of room for the highlights to survive and plenty of elbow room for a beautiful clean image."

:dankk2:
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Hi,

You should hava a look at the CML thread, they talk about regrading, you may want to chime in.

Sorry, I messed up on the ASA, I deleted my error fairly quickly but not quick enough!

Stephen
 
Jannard said:
David Stump determined that the Mysterium sensor is ISO 200, but he and many other experts will likely recommend shooting at ISO 320-400. That gives a ton of room for the highlights to survive and plenty of elbow room for a beautiful clean image.

Jim
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Hi Jim,

From of what I have seen from David's tests I would go with 320asa which FWIW is the same I would expose film rated at 500 asa.

David mention's who calibrated his light meters, however he does not say what they were calibrated to! Different manufactures use from 11.5% to 18% which is another 1/2 stop in somebody's favour!

Stephen
 
Y.Goh said:
boothba, I read a post from another forum that might be an interest to the reader of this thread, and kind of agreed with you comment too:
'....I am a bit surprised that after a gain of 3 F-Stops I get an entirely white image.
'
Click to expand...

David Stump replied on CML as follows:-

"That's why I think it would be valuable to revisit the matrix that maps the sensor to RGB. I feel confident that there is plenty of latitude in there just waiting to be dug out with a little bit of curve noodling"

Stephen
 
Greame has made an important discovery today that is yielding much improved results. We will do a re-shoot soon. Maybe we can talk David into coming down again. If not, we know how to light it this time. This is one of the things we opened ourselves up to by showing the work in progress. I'm good with it as long as people don't lock down what we are showing as final product.

Jim
 
Jannard said:
Greame has made an important discovery today that is yielding much improved results. We will do a re-shoot soon. Maybe we can talk David into coming down again. If not, we know how to light it this time. This is one of the things we opened ourselves up to by showing the work in progress. I'm good with it as long as people don't lock down what we are showing as final product.

Jim
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Jim,

Great News!
I hope you have found the comments from CML useful, possibly also saving you time.

Best wishes,

Stephen
 
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