Render time

vindazi

I have a project that is taking an unusually long time [over 8 hours] to render. It clicks along but starts to slow around 30% and then creeps to virtually a stop at 43%. I have quit and restarted but the same sequence repeats. Is there any way to render this? I am on a mac with 4 gigs of ra, and a duo core processor. The program says the file size is about 38 megs but such files have actually rendered at much smaller sizes in the past. I am rendering a png.

Rashad Carter

vindazi said:

I have a project that is taking an unusually long time [over 8 hours] to render. It clicks along but starts to slow around 30% and then creeps to virtually a stop at 43%. I have quit and restarted but the same sequence repeats. Is there any way to render this? I am on a mac with 4 gigs of ra, and a duo core processor. The program says the file size is about 38 megs but such files have actually rendered at much smaller sizes in the past. I am rendering a png.

A virtual stop? That means its still rendering under the hood. Personally, I've never known Bryce to fail in terms of rendering. If rendering starts then it will finish. There can however be certain elements within the scene that cause it to take longer to render in certain areas. Surfaces high in reflection, transparency and other considerations can really bump up rendering time. I suggest at this point you give us a little more insight into hat you are doing,maybe even a screen shot of the desktop at the point where the rendering slows down so we can try to help you get past that point. Best of luck.

Horo

@vindazi - difficult to answer your post without a bit more information about the scene. As Rashad already pointed out, Bryce never stops the render once started. There are people waiting for 3 and more weeks to have a render finished. Render hogs are: transparency, soft shadows, many light sources, IBL quality setting, IBL shadows and IBL soft shadows. Premium render settings like TA, DOF, etc slow the render at high RPP settings. Max. Raydepth settings above 3 or 4 start to slow the render down when there are reflections in reflections. And probably worst of all, Volumetric World. Bryce renders the scene completely or crashes after the first pass if there is something it doesn't like.

vindazi

I reduced the number of objects in the scene, and changed some surfaces. It still took the better part of four hours but at least it completed.

Thanks for the tips on causes for long renders and the heads up that extremely long render times sometimes happen. I hadn't experienced that be fore in stills and thought it was only related to animations.

vindazi

Now that I have the file completed for a render of about 8.5x11, I tried to render a poster of the same image. It is a 18x24 aspect ratio @ 315 dpi. The print requirements are 300 dpi and I boost it a little incase I want to crop a bit in Photoshop. Byce indicated it would be a 166 mb file.

Aside from taking a long time to render, it begins again the progress indicator resets to zero, though the bar and counter continues to "progress". At completion all I get is a black screen. When I get info on the files it has no data, i.e. zero mb file.. Any ideas on how to render this file?

Dave Savage

I never use "Render to Disc"

It's much better and safer to just hit the normal 'Render' button (the big one in the middle of the set of five spheres in the Left hand icon menu set.

When your render is complete, you can save the image in several formats from the File menu.

vindazi

When I've done this in the past the renders were pixelated. When I inquired about it I was advised to render to disc. Can I get the same render output controls as render to disc?

Horo

@vindazi - You want an output at 18 by 24 inches and your printer expects 300 dots per inch. So your document size needs to be 300 x 18 by 300 x 24 = 5400 x 7200. Mind that photographic prints have 100 to 150 lines per inch. I render for 135 lines (or dots) per inch and the result is great. Don't forget that 300 dpi in a printer means 100 dots per inch for red, 100 for green and 100 for blue. If you set the document size to 2430 by 3240 pixels and render you will get a good quality.

The 4000 pixel limit in Bryce to render on screen is only horizontal. Vertical, the document can be larger. And TheSavage64 is right. Avoid rendering to disk. If your document size must be wider than 4000 pixels, render as tiles and assemble the tiles in a graphics application. There are several strategies to do this. This http://www.horo.ch/raytracing/tuts/pdf/minitut21_en.pdf is one of them.

CTippetts

TheSavage64 said:

I never use "Render to Disc"

It's much better and safer to just hit the normal 'Render' button (the big one in the middle of the set of five spheres in the Left hand icon menu set.

When your render is complete, you can save the image in several formats from the File menu.

I, too, have never rendered to disk. However, it does have some value for long renders. David Brinnen explains in one of his videos I saw, (sorry I don't remember the link, but who here could forget that name), that; by rendering to disk, should you get to a point where you have to stop the render and shut down your computer, once you have it all back running again, you can resume that render where it left off, simply by loading it back in and clicking the same button you would to resume a non-disk render.