this post was submitted on 24 Oct 2023
1 points (100.0% liked)
Photography
24 readers
1 users here now
A place to politely discuss the tools, technique and culture of photography.
This is not a good place to simply share cool photos/videos or promote your own work and projects, but rather a place to discuss photography as an art and post things that would be of interest to other photographers.
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
The dual ISO is for video in order to capture maximum dynamic range when using LOG profiles. It’s got little to no relevance for stills photography, unless you’re shooting stills in log. Max DR for stills is usually at 100, with the R5 sensor it’s 50 according to our friends at DxO.
https://www.dxomark.com/canon-eos-r5-sensor-review-a-high-water-mark/
Great! Thanks for your answer my man!
Maximum DR ≠ minimum noise. The DR is higher at low ISO because the highlight headroom is higher, but the noise floor also is, and if you are light-limited, the latter may be more relevant.
Look at the other graphs. Best noise performance and colour depth is also at lower ISOs
“SNR 18%” is higher at lower ISO, but is also 18% of a higher saturation point, so it’s the SNR for a higher amount of light – no wonder it’s higher. For a fixed amount of light, as in low-light situations where you might be limited to, say, f/2 and 1/100s, the highest ISO setting that doesn’t clip anything you care about will lead to less noise. (More or less depending on the camera.)
See figure 6 of: https://www.mdpi.com/2079-9292/8/11/1284/htm
Or: https://www.dpreview.com/reviews/image-comparison/fullscreen?attr134_0=canon_eosr5&attr134_1=canon_eosr5&attr134_2=canon_eosr5&attr134_3=canon_eosr5&attr136_0=1&attr136_1=2&attr136_2=3&attr136_3=4&attr176_0=efc&attr176_1=efc&attr176_2=efc&attr176_3=efc&normalization=full&widget=487&x=0.06014373975539024&y=1.0840726817042607
(The effect is more extreme with the EOS RP.)