[Steve Bentley]

The first systems used high resolution gray scale monitors with RGBW filter packs that moved in and out between the crt and the lens during the exposure to create an RGB record from the grayscale image (so multiple passes for the same image). The problem (initially) was that film was differently sensitive to different wavelengths of light so the red would expose slower than the blue for instance. It also let every pixel in the screen make up part of the image instead of one out of every three “sub” pixels as would be the case for an RGB display.
Lasers came on to the scene much later.
The biggest issue was that the gamut of the film was so much wider than the computer imagery or the CRTs being used at the time. It was really hard to get clean whites without blowing everything else out and hard to get dark shadows without fogging the rest of the image due to long (in photography terms) exposure times. (Plus a CRT is never really off even where black is, so the dark areas were constantly exposing too. Try it – turn off all the lights in a room, close your eyes to get used to the dark and then turn a crt tv off and then open your eyes. That tube will glow for minutes!)
Some systems used a moving physical mask and scanned the image on the screen line by line. This was much slower but kept the contrast up because the mask kept the constant glow of the rest of the screen from exposing the film.

[Steve Bentley]

Its in the General tab of the preferences BUT it doesn’t seem to work. (Pshop 2018). I can change to Microsofts picker there and that works, but choosing between the Strip and the Wheel for Adobe’s does nothing and leaves the square version as the active type (even though the prefs did change).
Make that change and try a pshop restart, if that doesn’t work, throw out the prefs and try setting it again after a restart.

[Steve Bentley]

You mean the letter box or pillar box shaded areas that show your frame cut off?
Its in each view panel’s Options/Configure/View tab (the top of each view panel’s window) and its the Tinted Border your looking for. You can set the opacity and the color right next to that check box.

[Steve Bentley]

It worked for me initially too and then it didn’t. For objects where it always worked, it still does, but often new hidden but luminous objects light up everything even with an exclusion tag.
I thought perhaps I wasn’t using it right.
Normally we set up our “reflectors” or “bounce cards” and that’s it, but there’s so much reflecting stuff in this shot that the director is art directing it to the nth – ” I like that reflection there but not that one” even though its the same bounce card making both reflections.
At the moment we’ve had to do multiple renders with cards on in some passes and different cards on in other passes, and then generate masks to comp the multiples together. I tried using object buffers and doing multi passes but that didn’t work either.
We tried the argument that “if you did this in real life those are the reflections you would get.” But that backfired because the director said that’s why he wanted to use CGI and not shoot it, so he could have that kind of control.
Its just such a shame because it does work correctly for some of the “paired” luminous objects and lit objects, but not others. Very odd.

[Steve Bentley]

I just thought of something. Is that movement from the Alembic? Or did you animate that from a single “frame” of the Alembic. If the latter you can make the object editable (C key) and then you can apply textures as you normally would for regular geometry. You will lose all links to the alembic file though.

[Steve Bentley]

Is one render using the other render’s GI cache? Turn the caching off in the render settings and see if that cleans it up – did one render take much less time than the other? That’s another indication that the cache isn’t being recalc’d

[Steve Bentley]

Not quite sure what you are after there but have you tried making the spheres (or slightly larger versions of the spheres) matte objects with a compositing tag?

[Steve Bentley]

I think you are seeing the inside of the dark cap there refracted through the bottle shoulder and liquid. You can either map a lighter texture on the inside of the cap, or put a light in there that is excluded to shine on the cap only (or both: lighter texture and light) or you can put one of those security protective seals in there on the top lip of the bottle and make it white or green (even maybe luminous) but make it invisible to camera and only show in reflections and refraction.

[Steve Bentley]

But depending on the alembicis (is that a word? alembicness?) you may need to animate the texture to change as the geometry of the object changes.

[Steve Bentley]

Can you post of shot of what you do have? I wouldn’t have chosen hair as my first choice to create this effect.