This has happened twice now while working on my Blending Life project – after a successful render, I change a few layer specs, hit f12 again, and nothing but black is rendered, well actually it’s the ambient RGB, but you get my drift. It’s as if the models have suddenly become invisible. Digging into the material specs, Blender reports that every one of the texture maps used for every material cannot be found – “Can not get an image.” Furthermore, neither hitting Reload nor actually re-establishing the link through the image-load icon fixes the problem. The materials are rendered useless (pardon the pun).
Now, so far, just quitting and re-opening the file has been a fix, but that sometimes means losing hours put into rendering out individual Render Layers for the Compositor to chew on – they can’t be saved and need to be re-rendered.
So, is this a known issue, and is there some magic to kicking Blender in the butt so it will rememebr where the images are without having to shut down?
Try saving the file after rendering. Usually when I’ve had the problem it has to do with Saved Buffers. If you’re using OSA and you re-render a single render layer it boots the rest of the renderlayers (from the same scene only) from the file and they’re blank upon reopening the file (only at that point…they’re held in RAM until you close the file I guess). I’ve never had this problem with material textures (kinda weird) but hopefully the fix is the same. Good luck.
Thanks, RamboB, I’ll give that a shot, see if it recurs. It seems to happen with no identifiable precursor, i.e., a particular something I do first every time, so what the source may be I can’t even begin to guess. It may be memory-related, it usually happens when my system is flirting with the top end of its mem resources. If a file save relieves some of that burden, it may make the difference.
If that’s the case you might try lowering your levels of redo to see if it helps. Tabbing in and out of edit mode just once really eats a lot of memory if you have a highly subsurfed object and subsurf is enabled for edit mode.
No subsurf at present, but I am often working at Multires Levels 3 & 4 in the UI, which I suppose is comparable. I don’t use multiple undo that often anyway, so reducing the levels wouldn’t be a hassle. Thanks for the tip.
I just noticed this as well and it was because the render layers were not in synch with the layers in the 3D window. (i.e. the layer the light was on was not selected.)
Atom, do you get the “Can not get an image” report in the image load panel as well? My Render Layers and those selected for rendering in the 3D window synch up OK, and the lights layer is active, but Blender refuses to “see” the image maps I use for my materials.
The “can not get an image” error is usually due to the internal Blender path limit. Try moving your image or movie to the root of the drive and re-browse to it. I have seen this as well, especially when moving a project from one machine to another. Once the path length is exceeded, the internal mechanism ends up in a file not found state.
Sounds plausible, except that nothing has been moved, no files, no textures, nada. For most renders, everything is fine, all textures found & used, but then suddenly, on the next render, everything is lost and cannot be found, or the paths re-established even directly with the load button. I can’t say it makes sense to me for the path to be valid for one render and not for the next, but then none of this makes sense :spin:
Another aspect I hadn’t realized before – it happens only when I’m rendering to a large image size, about 1275x875.
However, lately, at all image sizes, I often lose the image from the F12 render buffer (that may not be the correct terminology – frame buffer?), e.g., I switch from the render window to the UI, then hit f11 to bring the latest render back, and it’s blank. Spooky, though this may be related to my using the Compositor, from what RamboBaby has said.
You may want to try F3 and save the render buffer to disk. just to make sure it is not a video driver bug. If the image is there, you could load the saved image into gimp or photoshop to verify.
I would still consider moving the project to the root, just as a test. I mean, if you are stuck, why not try that. What if you are only one character away from the path limit, so frame 1 renders fine, and frame #10 crosses the path limit, just by adding another character to the filename output?
That definitely sounds like a memory issue. I have seen Blender crash many, many times on composite (the render went just fine) due to large .png images loaded into the compositor.
If you’re not using the Save Buffers option then doing so may help because Blender will be reading your image (previous render) from disk rather than holding it in RAM. Using the Free Tex Images option may also help. I don’t know if these options work properly on windoze yet but I do know they’re much better than they were a year ago.
Like Atom, I typically work from root folders, one for temp files and one labeled Blender projects with an occasional sub folder.
I’m currently using the Save Suffers opt, and will try the Free Tex as well. The problem hasn’t surfaced again lately, though. Moving to a “shallower” level in the path length is also a good idea, if the problem shows again I’ll try that as my next step. Right now I’m about to start my first “final” full-size render, so I’d rather not tip the boat too much my moving files around as long as things are relatively stable.
Hey, thanks, RamboBaby. No, I’m not much for blogging, never caught the urge, I guess, maybe age-immune? But I do write tutorials now & then, more my style, I guess. Maybe after The Pugilist is done I could combine the media a bit and put down some info about some of the techniques and stuff, maybe a retro-blog?
I have a WIP thread here on ba.org but haven’t updated lately because visually there’s really not a lot new to see. Currently even my partial test renders are running well over an hour each, so I can only get so much done in a day, it’s real slow. For example, just the SSS pre-processing and “pre-render” on the full-size image has taken over 11 hours so far and it’s not even done yet! Even 1/2-size renders with all the settings at final take about 14-15 hours, so I’m not making as many of them lately.
But I do write tutorials now & then, more my style, I guess. Maybe after The Pugilist is done I could combine the media a bit and put down some info about some of the techniques and stuff, maybe a retro-blog?