A basic question on Texture Compression in Render Settings

Umi no Senshi no Ishi

I sprung for a 3090 card as Amazon had a swet sale over the (US) holiday weekend.

Got it installed and went in to Render settings to make sure Daz sees it, all good.

I've never messed with the advanced render settings beyond making sure my card is seen, and noticed the "Texture Compression" section at the top of the tab.

My medium threshold is at 512 and high threshold is at 1024. 

What do these settiongs apply to?

I'm assunming something in Iray is going on under the hood depending on the texture of the surface. anything above 512 it uses Medium "settings" and above 1024 it uses high.

Change curious, always want to learn, no issues.

PerttiA

The "512" and "1024" are referring to pixel size of the textures used on the model.

Nowadays, the textures tend to be 2048x2048 or 4096x4096, which means that the process is using high compression for all the textures.
In practice the default compression settings are reducing the memory load to about half = If the textures use 1GB of RAM, they will take about 500MB's of VRAM when rendering in Iray.

Does not matter what the size of the imagefile on disk is, as the images are handled uncompressed when loaded to any program. One 8192x8192x24bit image will use 192MB's of memory (RAM)

Umi no Senshi no Ishi

Thank you for the explanation.