rendeing to 32 bit .... how to make the most of this in Photoshop?

[Chog Burley]

hi there,

 

I have been doing a fair bit of reading around the subjects of linear workflow and gamma. one of the recurring themes is rendering to 32 bit EXR files which apparently offer a greater range of possibilities for post production.

 

this is mentioned in the following (i can't add links yet due to the forum software!) :

 

- Floze's excellent lighting tutorials

 

- a good thread ion creative crash (google creative crash linear)

 

- the "making of" video of Alex Roman's 'third and seventh'

 

my question is ... once i have rendered a 32 bit EXR file (out of Maya/MR) i take it into photoshop and switch to 32bit mode. however, when experiemnting with Levels etc i don't find any difference than in 16bit mode. in fact i seem to have less control as many features (layer modes eg) are not available.

 

am i missing something really obvious such as rendering with more blown out highlights to give more range that i can correct later?

 

any tips much appreciated ... there seems to be little written about this that i can find.

 

CB.

 

ps attached is the image i'm working on.

Edited February 13, 2010 by cbAVA

[DavidR]

I find that 16-bit is enough for the arch viz stuff I do. You will see a big difference between 8 and 16/32-bit if, eg: you have a dark rendering and want to make it much brighter; with 16-bit, you can go nuts with exposure in pshop without wrecking your image, especially visible in shadow areas, where you would otherwise get alot of banding. You can't see a difference between 8-bit and higher until you modify, then the flexibility of 16+ is clear. After I get what I want, I convert it to 8-bit to keep file size reasonable.

[mattclinch]

you should not have to 'switch to' 32bit mode in PS when you open a 32bit EXR - it should open it like that by default. if you are opening your EXR file and PS stays in 16bit mode, your file is not 32bit, in which case i would say you have saved it out incorrectly. i would check your frame buffer (? not sure about how MR works in Maya) is in 32bit mode and when saving to EXR you are choosing the correct settings.

[Crazy Homeless Guy]

I concur on no real need for more than 16bit color depth in 99.5% of all arch images. You will be amazed by what you can do with 16, and if you are working in Photoshop you will have to switch to 16 anyway shortly after you bring it in. Many important Photoshop tools are not supported in floating point formats.

 

I would recommend saving to a 16bit floating point EXR file. It has a very small footprint compared to other 16bit files.

 

P.S. Photoshop is not great at handling floating point anyway. It can open them, and do fairly crappy exposure adjustments, but beyond that, it is rubbish. Maybe I am missing a major feature, but I think floating point in Photoshop is highly over rated.

 

It is my understanding that you get the real benefits of using floating point when you get to software like Nuke and such.

 

As for your image... I think you should focus more on color grading, and contrast make it special in post.

Edited February 14, 2010 by Crazy Homeless Guy

[Chog Burley]

hi guys ... many thanks for your responses.

 

first off, my mistake ... the images did open in 32 bit mode so i think they have rendered properly. i will stick to 16 bit though and see how that works out - as you say, most of the filters etc don't work in 32bit anyway.

 

is AFX much different to PS for floating point? Nuke would be nice but is a bit beyond my means at the moment. Maya comes bundled with Toxik however so will look into that.

 

Crazy Homeless guy - for the colour grading and contrast, i assume you mean using Photoshop? learning to do good quality post work is my next mission! i found a good tutorial by Juan Altieri on here and some bits in Advanced Photoshop magazine's 'Expert Lighting Slills', but any pointers you might have or tutorial suggestions would be much apprecaited ...

 

thanks again,

 

CB.

[Chog Burley]

this retouch looks a little better (i hope!)

 

Cb.