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Lenses are putting a practical limit on DR to 14 stops?


kye
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I am completely blown away by this, but it's great news.

In another thread, @sanveer has shared a link to Imatest who have shown that lens design might be the limiting factor to the DR of a setup, not the sensor.

2 hours ago, sanveer said:

Your be glad to know that 14 stops is the theoretical limitation of a senior's dynamic range, because of the lens flare. So everyone claiming 17 stops, are just gassing. Without exceptional lens coatings on on all lenses of the various lens elements, it is apparently impossible to breach the 14 stops limit. "Camera DR is often limited by flare light, which is stray light in the image, primarily caused by reflections between lens elements."

https://www.imatest.com/2019/07/making-dynamic-range-measurements-robust-against-flare-light/#:~:text=Introduction,by reflections between lens elements.

This is great news, especially for those of us who aren't shooting on the most pristine modern lenses, and don't want to.  It means that we don't need to keep buying cameras with higher and higher dynamic range specifications.

I have actually been chasing lenses that have slightly less overall contrast so that the veiling flare pulls up shadows, giving the sensor a bit more light to digitise and getting it a bit higher compared to the noise floor.  This also makes the image much more like film, which has a nice shadow roll-off and looks more organic.

Lots to unpack in this one.

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EOSHD Pro Color 5 for Sony cameras EOSHD Z LOG for Nikon CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

That's bullshit. Set up your camera on a tripod with a hight DR scene. Set up your aperture and now braket through exposures. The lens image will not change. If this statement were true you just would see fill light in the shadows, no detail.

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1 hour ago, kye said:

I am completely blown away by this, but it's great news.

In another thread, @sanveer has shared a link to Imatest who have shown that lens design might be the limiting factor to the DR of a setup, not the sensor.

This is great news, especially for those of us who aren't shooting on the most pristine modern lenses, and don't want to.  It means that we don't need to keep buying cameras with higher and higher dynamic range specifications.

I have actually been chasing lenses that have slightly less overall contrast so that the veiling flare pulls up shadows, giving the sensor a bit more light to digitise and getting it a bit higher compared to the noise floor.  This also makes the image much more like film, which has a nice shadow roll-off and looks more organic.

Lots to unpack in this one.

Not much to unpack here at all...

As I noted in that other thread, the Imatest article is a PSA (of sorts) to help educate its customers about "exaggerated" DR claims being made while using their (Imatest) equipment. Their "Key Takeaways" section at the bottom of that link pretty much says it all.

😉

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Read the full article please?

Quote

Key takeawaysFlare light was not an issue with the high-quality DSLR/mirrrorless lenses we tested in the past, but it has become a major factor limiting the performance of recent low-cost lenses intended for the automotive or security industries. We have seen examples of how flare light can improve traditional DR measurements while degrading actual camera DR. 

Our approach to resolving this issue is to limit quality-based DR measurements (the range of densities where SNR ≥ 20dB for high quality through SNR ≥ 0dB for low quality) to the slope-based DR. This works because, for patches beyond the slope-based limit (where the slope of log pixel level vs. log exposure drops below 0.075 of the maximum slope):

Contrast is too low for image features to be clearly visible.

Signal is dominated by flare light, which washes out real signals from the test chart; i.e., the “signal” is an artifact, not the real deal.

Limiting quality-based DR in this way significantly improves measurement accuracy, and perhaps more importantly, can help prevent inferior, low-quality lenses being accepted for applications critical to automotive safety or security.

 

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I just want "enough" DR for any given use.

Every camera i have had is different and I have never said that any of them did not have enough.

I have had an old Canon G10 (pro grade with a tiny point and shoot sensor photo camera) and it took lovely photos (at base ISO only) but had about the same DR (about 10 stops) as my A7s has at ISO 6400.

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