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alecorre
03-22-2006, 05:16 PM
Hi

Can someone give a definitive answer on what settings to render for a film test.
We are going to do a very small test as part of a feasibility study and want to get everything correct.

Software - Maya 7
Renderer - Mental Ray
Resolution - 2k and 2:35 to 1 ratio (we are assuming 2048 x 872 and square pixels) if this is incorrect, then what are the correct render settings?
image format - .tga?? Which is the recommended file format to use and what are advantages and disadvantages of each?
frame rate 24 fps
Compositing software - After FX
Editing software - Adobe Premiere
color depth of images - 8 bit, 16bit, or 32bit? can we just use 8 bit depth?

Thanks

Allen

rendermaniac
03-22-2006, 11:27 PM
If you are getting something filmed out then you should really speak to the people doing the filmout - they will know exactly what formats that their scanners take.

The file format is pretty easy - pretty much all recorders take 10bit log Cineon (possibly DPX but that tends to be used more for telecine/DI... you'd have to ask). Going straight to Cineon from 3D is usually not too great an idea as it gets fiddly. I am not even sure if Mental Ray supports it - although it does seem to have a lot of file formats.

I'd render out as whatever linear format you want - most people these days use half float 16bit EXR, it used to be 16bit (integer - not as good as float) TIFF - and then output from 2D as Cineon. I wouldn't recommend 8 bit as it doesn't have the precision to go to 10bit log (unless you do mad things like using 8bit log - it has been done before).

Generally recorders at 2K record out full app at 2048 by 1556 pixels. If you want 2.35 then the usual options are to go for Super35 or Anamorphic Cinemascope. Super35 is easiest as you just mask (hard or soft) the frame down to 2.35, however you get a lower quality image as you waste quite a bit of film. It also benefits from not having to use anamorphic lenses. In this case you would render at 2048x871 as you said (I don't know if a pixel or 2 makes a difference before you ask ;)). Or render ful app, but this is pretty wasteful (of disk space and CPU time).

The other way of doing Cinemascope is anamorphic which uses more of the film which is 1828x1556 with a pixel aspect ratio of 2. However this gets more messy as you'll need to use anamorphic lenses to project it and it could cause problems for 2d.

The other common format is 1.85 accademy which I think has an offset to account for the sound track.

And then of course there is the whole issue of which film stock and how to match it on your monitor ;)

Anyway the best people to talk to are the recording bureaux doing the job - they are paid to know this stuff much better than me!

Simon

Andrew W
03-27-2006, 05:57 PM
Another thing to consider as well as bit-depth is some film colour-cube emulation software. This is because not only does film have a different response gamma-wise to monitors it also behaves very differently in its treatment of colour. Pretty much every studio will use some kind of look-up table (LUT) on the artist's workstation to emulate what the image will look like on film and this is often very different to the regular monitor display.

http://www.filmlight.ltd.uk/ are a highly regarded firm in this field.

If you can get some wedge-tests (single frames of different colour-balances and exposures) done before your main shoot that should get you into the right ball-park in terms of what settings you will need to be use to get the look you want.

If you can get hold of Quantel's book, "Film in the Digital Age" you'll find it very imformative though I don't know if it's widely available.

All the best,

AW

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