VFX in 2k using Combustion

[alphatron]

I'd say it heavily depends on the amount of post-processing, and the nature of the compositing.

But I'd suggest a motherload of RAM, as much as you can get, 2gigs minimum. I think no matter how highend the system, the going will be slow.

I just did an SD project on a high-end system, and it choked plenty of times.

GOOD LUCK :thumbsup:

[chicolima]

Thanks for your reply man!

[Cogliostros]

I'd be more worried about the final image quality then the performance hit...

being that Combustion is only 10bit, you will be clamping your 2k information to that 10bit depth... meaning that you will lose information that you might need in your comp. Its hard to say because I dont know what kind of comp work your doing and what the footage looks like, but just realize that you wont be returning all the lush detail and information back out to film once your done compositing...

[alphatron]

Combustion can do 8-bit all the way to float, and with great LUT support. I don't think he will have much of a problem in this area.

[beaker]

Originally posted by Cogliostros
I'd be more worried about the final image quality then the performance hit...

being that Combustion is only 10bit, you will be clamping your 2k information to that 10bit depth... meaning that you will lose information that you might need in your comp. Its hard to say because I dont know what kind of comp work your doing and what the footage looks like, but just realize that you wont be returning all the lush detail and information back out to film once your done compositing...
Cogliostros: that was many years ago with combustion 1.0, 2.0 added float support.

[Cogliostros]

wait what year is it?

:surprised

I apologize, please ignore my idiocy

:hmm:

[chicolima]

Hi guys,

In this job we'll mostly be doing set extensions uing 3ds max and combustion and a 3d tracking software which we still haven't decided for.

I read that SceneGenie, 3ds max plugin, is one of the best and the cost is incredible. It was used on Minority Report by Matt Merkovich. Amazing job!

We'll scan the Film in 2k at 10bit log Cineon or DPX files, the fileformat will depend on the scanner we use.

We'll be using LUT files in order to see the images correctly.

Thanks again.

[crgowo]

sorry if this is a stupid question but whats "lut?"

[alphatron]

Stands for Look Up Table. Basically, scanned film and 10-bit HD is outside the maximum colour depth that our videocards/monitors can currently display. The display will try to compensate by clamping these values down to 8 bit range, leading to a washed out picture.

The LUT takes the color depth info and displays the image as close as possible to its original on your display. This doesn't alter the actual footage, just the way it looks on screen, so yu can do color corrections and other operations.

Technical explanation:

http://www.dome.com/support/articles/lookuptables.html

What Is a LUT?
A LUT is a simple approach to convert a set of input pixel values to a set of output pixel values. For example, with an 8-bit grayscale imaging system, there are 256 possible gray levels (0 to 255) that may be output by an image digitizer. Each output value could be mapped or translated through a (software) equation to derive 256 new output values. Many equations exist, ranging from very simple linear relationships to more complex logarithmic and exponential transforms. Alternatively, all the new output values could be precalculated and loaded into a hardware table implemented in dynamic random access memory (RAM) to speed subsequent operations. For an 8-bit grayscale system, there are only 256 possible outputs to precalculate; for a 16-bit system there would be 65,536 values. The table, or LUT, uses the input pixel value to determine the address location within the table, and provides the contents of that address as the output pixel value.

[Alanbell]

I work in 2k and 4k with combustion all the time. It's excellent especially when it comes to matching color. My clients have been very happy with the results.

I'm on a dual 1.25 G4 with 2GB ram. You need to flush the cache all the time. And certain areas of the program a unstable such as paint. Just save your work often and don't sweat the crashes.

If you have any specific questions I'll be happy to elaborate.

Regards
Alan Bell

[chicolima]

Hi Alan,

Thanks for your reply and in case I have any more doubts I'll send you an e-mail.

Francisco

[dg]

Hi all!

Heya Alan, Chico :)

Well said Alan flushing the cache in C is the key to survival, another good thing to do when things starts to get nasty is to commit to disk.
Chico another good option would be Digital Fusion, it's a really stable app, and he also works great with big stuff.

Chico haven't you decided about the camera tracker yet?
Can't wait too see the final result :)



Well I'm off,
See you all later! 8)

[chicolima]

Hi Diogo,

We ended up using Inferno's 3D Tracking module.

We just finished this Feature film and as soon as it is release, end of October, I'll be able to send you some shots that we used 3D tracking.

Thanks Diogo!

[crgowo]

by flushing the cache do you mean with a program like rampage from highend3d.com, that shows you how much freememory you have and let lets you free memory when it gets to low?

[Hugh]

In Combustion, there is a little 'Memory Indicator' in the bottom right hand corner of the screen - if you R-Click on that, you get a pop-up menu, the bottom option of which is 'Flush Cache'

This is, I believe, what is being talked about here...

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