saving images file type

[SgWRX]

i've gotta say that although i understand the importance in photography, i recently tried saving some rendered images at 16-bit tif files and the difference can be quite striking compared to saving an image as a jpg.

 

a simple photoshop plugin or even using irfanview easily shows the number of colors in each image and one i'm looking at right now is 2million vs 287thousand. and this is with the rendered frame buffer being set to 16bit per channel, not even HDR format.

 

in particular i'm noticing that an hdr image i'm using for sky is much smoother blues and more fluffy cotton like look in the transition from blue sky to clouds.

 

i've applied a pretty dramatic s-curve to both images and as expected the 16-bit tif has faired better.

 

i think it's time to switch completely over.

 

not sure about saving as OpenEXR though? i'll look into it, just thinking off the top of my head it would add a bit to the workflow?

[Scott Dombrowski]

I've been saving OpenEXRs for a while. Usually 32bit because storage is cheap. The biggest benefit is adjusting the exposure after the render. If you're in a huge rush (like my projects usually are), you don't have to nail the exposure in Max. Save it as a 16 or 32bit EXR and you can make pretty major adjustments in Photoshop that you can't do with an 8bit. With 32bit, you can save out passes for each set of lights in your scene and set the blend mode for each pass to Linear Dodge (Add) in Photoshop. Then, with an exposure adjustment layer on each light pass, you can dynamically make the lights brighter and dimmer, just like if they were on a dimmer switch.

 

The downside to 32bit is that you have to change it to 16bit in order to save out .jpgs. I usually get the exposure where I want it, then convert to 16bit before I do any major compositing work. If you do it after, you'll get a visual shift in how layers blend together once you do convert.