Alright, I am back with a second test, this time concerning the highlights as mentionned by
Reddeercity and
yourboylloyd.
First the variables :
Canon 5D Mark II 2.1.2 w/94k actuations
Canon 35mm F/2 IS
VAF 5D2 AA Filter
SanDisk ExtremePro 32Gb UDMA 7 160MB/s CF card
magiclantern-crop_rec-3k_Updated_Center_4.20pm-5D2-eXperimental.2019Nov14.5D2212 from Reddeercity
100 ISO
1866 x 1044 1.00x Crop @ 23.976 fps 1/50s
Methodology :
I started with a very over-exposed sky and brought down the exposure by 1/3 ev using the aperture.
Test starts at f/6.4 and using the raw zebras as mentioned in the thread. I then pulled back two settings in ACR, exposure and Highlights. Exposure is brought down relatively to the aperture setting so that the resulting image is the same exposure across the board. Highlights are always pulled back @ -100.
I did two rounds, first at 10-bit and the second at 14-bit. Something that I encountered however during the recording is that the RAW zebras did not show while recording 10-bit footage. They were displaying fine while looking at live-view without recording, but as soon as I started recording, the zebras turned standard.
Here is what I am talking about. First image is while recording 14-bit, second while recording 10-bit.
Here is a reference picture of the scene I made with my iPhone 7 Plus :
Moving on to the actual tests, here is the 14-bit :
And here is the 10-bit :
Don't forget that you can click on these images to view in full resolution.
Can you tell the difference ?
Here are all my files from the test, DNG's, xmp profiles created in ACR, PSD files, exported JPEGs and everything in between.Conclusion :
It seems that both 14-bit and 10-bit depths handle high exposure detail very, very well. Both can be ''metered'' about the same for the highlights. From what I can tell, we lose detail in the clouds at f/6.4 and f/7. We start seeing consistent detail in the clouds at f/8. Coincidentally, f/8 is when the black bars in the RAW zebras don't appear anymore. I would conclude that using zebras for exposing and looking for an exposure just before black bars is a great way of getting all the highlight capacity of the sensor. I had trouble seeing the difference in this scene from 10-bit and 14-bit. In my eye, they both seem equal. I did not test 12-bit because the difference was marginal compared to 14-bit in the first test.
The bulk of the difference that I wanted to expose is between the two extremes. This does support my hypothesis in the first test that highlight detail seems unaffected by bit depth.
I also took the good exposure picture (f/8) and pushed the shadows to 100%. I looked for areas where I could see differences. Here is another example of the green cast in the shadows when pushed to the extreme (Shadows -100) :
You can see what I am talking about in two places : the back of the stop sign and the window frame. In the 10-bit portion (left) you can see some green cast in the recovered shadow areas, but the cast is much less severe than the initial test. There is however much more grain. Its especially visible in the window frame section in the middle.
Conclusion of the conclusion :
10-Bit is
AS GOOD AS as 14-Bit for highlight detail retention @ 100 ISO. For shadow detail when pushed up +100, 14-Bit still holds an advantage, albeit less than previously thought.
VAF filter comparison coming soon.
