sanity checks for editing Nikon NEF files

It usually says 14 bit if you look…at least likely and Nikon often seems to omit the raw black and white from this 0 to 16384 would be the data range… one canon file I looked at yesterday was 14 but with a bp of 1024 and wp of 10814 or something like that… so for that file the data that are likely linear and not clipped are in that range… Those numbers for your camera and RT are in a JSON file . I’m on my phone so I forget the exact name and location but it should be easy to spot in the RT program directory

Edit…

camconst.zip (40.3 KB)

The \mathbb{Z}\sf8 sensor was measured at over 26-bit color depth for ISO 64. Nikon Z8 Sensor test - DXOMARK

The \mathbb{Z}\sf8 only records 14 bit NEF RAWs, so where you stand on the noise floor all depends on the ISO you shoot.

Why is this ok? The dynamic range of the sensor is 14.2 Exposure Values. This quantum range is independent of it’s color sensitivity.

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Late to the party and can only offer experience with RT 5.8. Win 7.

Some cameras’ embedded JPEGs are noticeably different to converted raws in review images.

When RT opens a Sigma DP2 Merrill X3F raw, there is always a horrible green vignette around the edges - which tells me that a conversion was attempted by RT.

There is no such artifact in the embedded JPEG and it does not appear in the Sigma proprietary converter review either.

With the Sigma example, it is obvious which is which, but I imagine there must some metric for NEFs that would tell the tale …

P.S. there are apps that can convert the raw or, by selection, extract the JPEG. e.g. FastStone Viewer.

Also, with an NEF open in RT you can select various conversion algorithms. If the review image changes, it is unlikely to be the embedded JPEG.

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I’d really flip this around: do you have any reason to doubt that the camera delivers raw files that live up to the promised bit depth?

A 10-bit image would have raw white levels no higher than 1023; for a 12-bit image, the theoretical maximum is 4095; for 14 bits, 16383; for 16 bits, 65535. Those values you’ll find on the raw tab, I think.

As for noise, there are many tests, including https://www.photonstophotos.net/ and Camera Sensor Ranking - DXOMARK.

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Red Herring. You would also need to know the ADC manufacturer’s published ENOB (Effective Number Of Bits) - for example, it’s 10.5 for the 12-bit one in my Sigma camera.

z8

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Sorry I went back and saw that after reading a few missed posts… basically as noted above if the demosaic option is active and being used its a raw …you are not going to see this with a jpg