Uni-WB files

[simsurace]

I produced my Uni-WB files using Guillermo Luijk's method:
http://www.guillermoluijk.com/tutorial/uniwb/index_en.htm
He has collected a bunch of files that are available for download (scroll down on his page).

In case anyone uses Uni-WB occasionally and has files to share, I suggest to link them here.

In a nutshell, Uni-WB files are a workaround to get the camera RGB histogram to approximate the histograms of the RAW data. This is required to get exposure-to-the-right (ETTR) (or any other manual exposure) correct without too much guesswork. If only Nikon (and other manufacturers) would give us RAW histograms, we could forget about this work-around, but for the time being, this method will remain the only method to do ETTR. The image review on the camera LCD will have a pronounced green cast which reflects the true spectral sensitivity of the camera sensor.

You can download the file I just made for the D750:
http://www.suracephoto.com/wp-content/uploads/2016/05/UniWBD750.NEF_.zip

To use it, rename to _DSCXXXX.nef (where XXXX is an arbitrary four-digit number; thanks to Akira for pointing this out), copy it to a memory card and insert the memory into your D750. Navigate to Shooting Menu > White Balance > Preset manual. Then select a slot, press the Zoom Out button. Go to Select image and select the file above. Hit Ok. It might be good to protect the slot such that you don't overwrite with a custom WB when using the WB button later on.

[Akira]

Simone, thank you very much for your effort and courtesy.

I downloaded the zip file and applied your UniWBD750 on my D750.  I needed to rename the file to "_DSCXXXX" (XXXX is supposed to be the four-digit number) so that the camera recognize the file (AdobeRGB).

The test shot with the new custom white balance looks more greener than shown in the website you linked.  Do I need to set the color space of the camera to sRGB, or is the color space setting also irrelevant (because it only affects JPEG files yielded in the camera)?

[simsurace]

Simone, thank you very much for your effort and courtesy.

I downloaded the zip file and applied your UniWBD750 on my D750.  I needed to rename the file to "_DSCXXXX" (XXXX is supposed to be the four-digit number) so that the camera recognize the file (AdobeRGB).

The test shot with the new custom white balance looks more greener than shown in the website you linked.  Do I need to set the color space of the camera to sRGB, or is the color space setting also irrelevant (because it only affects JPEG files yielded in the camera)?

You're right, I should have mentioned to rename the file.
Yes, the degree of green-ness varies from camera to camera. It depends on the color filter array I guess.
For best results with the histograms, I would suggest AdobeRGB and the 'Flat' picture control.
I haven't tested it out very carefully with the D750, but I made a test shot today where I exposed to get the live view histogram as far to the right without having it stick to the right border (if you know what I mean). The resulting raw file was pretty close to ETTR as checked in RawDigger. Maybe it would have beared 1/6th of a stop more exposure, but not much more. That's about as good as it gets. If in doubt, it's always better to subtract 1/3rd of a stop or bracket rather than blowing important details.

[Akira]

Thanks for the further explanations.  I think I understand the ETTR method.  I will make some test shots whenever my time allows.  I did a quick test by setting my D750 to the highlight priority metering, but the exposure was far below the ETTR value, so I discarded it.

[simsurace]

Yes, I think highlight-weighted metering mode was not designed for ETTR, it serves a different purpose.