Why does 50% grey in Photoshop show up as 45% in Premier on the Lumetri Scope?

https://thephoto.exchange/2018/02/20/minor-whites-zone-system-manual-revisited/

This is getting interesting. Thanks for sample, Neil.

Somehow I think the link between tones and IRE and NITS should somehow relate to lattitude. Raw is X number of stops ( theoretically very broad ), while LOG is also X number of stops ( 13 ?? - 14 ?? ). But just picking 16 out of thin air doesn't really do anything other than supply you with a tonal range that may or may not represent the capability of the media to reach those levels ( ylift, ygamma, ygain ) legally.

??

Nice to make stuff though... so you can compare or something ?

Let's say you print that scale at 300 dpi and use it when you shoot ... like everyone shoots charts at the beginning of a episode or film etc... so the post guys has a reference ... lit with the right light ( WB ).

fascinating.

I created a chart in Premiere using the EGP ... just made a series of rectangles, filled them with white but set brightness of each box with a mask on so that was all that was showing and watched the scopes.

This was in 16 equal separations for brightness for the main boxes, with a narrow one at 55 and a small box at 45. I've used this coupled with a ramp as below to test how say LUTs are modifying the image. Or what specific tools are doing when set a specific way.

Neil

That's pretty close and I doubt it will improve to be exactly the same in psd and ppro.

I did same thing years ago ( color chart ( rgbcmyk and 10 zones of greyscale ) and find it's not exact, even if you choose color space of hdtv rec 709 in psd, etc.

Best bet is to show the color 'bars' in ppro as a reference in that program.  Then it's a matter of calibration of the individual monitors how close it is to SMPTE standard.

In the old days a zone 10 thing was used for Minor White's large format b&w ( mistakenly attributed to Ansel Adams mostly ) manipulation of contracting and expanding the zones with a two bath developer. Now it's kinda a lost art and not many even know what it is for.... the zone system.

It won't translate well into video.

Photoshop is oft set for straight sRGB or farther out for color spaces, gamma/gamut. Often worked with gamma 2.2.

Premiere is straight Rec.709 video sRGB, with an assumed gamma of 2.4.

I would guess that is the issue here.

Neil