Strenghth Maps: Colour or Grayscale? render resource question.

wancow

Not getting a response on CGTalk, so I'm hoping someone knows the answer.

I applied an ambience strenth map to a background that was 24 bit, basically I pushed the contrast and got a good effect after I applied it.

My question is this: IF I had made it Grayscale, would it have taken less resources at render time, or does it matter at all?

fixmypcmike

I would think it would use less memory if it were grayscale, but I can't say for certain.

wancow

I'm thinking that as well... but it would be interesting to find out... the reason I'm hesitant to grayscale the maps is because I don't want to screw up the settings and have different ones for the various maps, which would be noticeable in the render.

ReDave

If you are already using the colour ambient map I would imagine its less costly to use it again as Strength map, than to add another map.I haven't specifically tried to add a greyscale map, but I tried a few tests by plugging the Diffuse map in Ambient channel and I'm not sure I see a difference memory-wise (according to Task manager).

wancow

just applying the colour map as a strength map wasn't possible in this case. I needed the ambiance to deepen the scene, which required a high contrast map. Try doing that, you'll be amazed at the difference. All I'm asking is this: would it have been better to make it grayscale?

ReDave

I've been toying with that idea since about last October, I'll do it sooner or later. ;)
Greyscale will take less memory regardless, but I don't expect it would make a huge difference unless your map is huge.