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trentonia
04-24-2007, 12:48 PM
I'm trying to render an image 12000 x 9000 and keep getting a message "not enough memory for frame buffers". What's up with this? I have a 3.2GHz Xeon with 2 GB of memory. I've tried raising and lowering the segment memory and that doesn't help. I get the same message if I try to render a limited area. Does anyone have any ideas how I can make this work? Thanks.

Surrealist.
04-24-2007, 02:00 PM
From my experience, it means what it says. You don't have enough memory for that size of a render and you also don't have enough memory for one at your limited region size either. Having had this problem and seeing others try and solve it I am of the opinion that you are not likely to find a solution to render at that res. If you find it I'd love to hear it. If not, try this:

The solution is live with a resolution that you can render. Keep lowering your resolution.

Then, take the image into photoshop and using bicubic resample, with resample selected, increase the image to the desired size, wait, save.

Done.

For print at 300 dpi I render an image that equates to 300 ppi on an 14.5 image area, that's 4350 pixels by 4350 pixels. I then blow it up. The largest size is 40.5 x 40.5 inches and the resolution after resample is 12,150 x 12.150.

I print these at photo quality for retail art prints and they hold up beautifully with no visible artifacts. So that is roughly a 3 x blow up. Just make sure your original is clean as it can be at that res.

trentonia
04-24-2007, 02:13 PM
Thanks Richard. I did a bunch of searching around and that seems to be the general consensus. I found that I can render at the equivalent to 150dpi.

tektonik
04-24-2007, 03:04 PM
the only sane solution is to go to XP64 and LW64

otherwise you never know when you will hit that small memory wall in LW32

in 64 bits no more stressing about scene or geometry size!!!

Paul Brunson
04-24-2007, 03:06 PM
At times when I've need super high resolution images I've used limited region to break up the image into smaller parts and then assembled them in photoshop.

DStorms plugin "Divide Scene" is great for this.

http://www.dstorm.co.jp/english/plugin/scene.htm

You can specify rows and columns that your image should be broken up into and then it saves out a scene file for each segment. For example if you break your image into 6 columns and 6 rows you end up with 36 scene files saved out. It then becomes a matter of rendering a frame from each one of those scenes and stitching the images together. (Hint: Use Network Rendering to batch render all those scenes)

The most important trick to making this work with extremely large renders is to use the "Limited Region" and "no borders" options in the plugin. (You can find the corresponding lightwave setting in the Render Globals panel; "Limited region no border")

Using this technique I've found you can render images up to the maximum resolution lightwave supports 16,000 x 16,000. Usually I've found you have to break it up into at least 6x6 columns and rows. Possibly more depending on the other RAM requirements of your scene.

(Warning: No matter how simple you scene is, rendering at 16,000 by 16,000 is going to take some serious time. On a complex scene be prepared to say goodbye to your computer for several days, maybe weeks :) )

toby
04-24-2007, 03:24 PM
How far did you lower the Segment Memory Limit? Low enough that the image was split into 10 segments? It should work if you go low enough -

BeeVee
04-25-2007, 06:27 AM
Worth bearing in mind the way LightWave handles images too: LightWiki (http://www.lightwiki.com/index.php?title=Optimised_image_use)

B

Exception
04-25-2007, 08:54 AM
Split the image up vertically, and let the segment memory limit split it up vertically. You can and should be able to render that size image in 3 limited region renders that way, as tall strokes. Make sure to use "limited region no borders".