Limiting factor for image export?

ScottPara · 3 Jun 2008, 12:16

When exporting an image what are the reasons for getting an error message for an image bigger than 4000 pixels with anti aliasing on? I understand you can export larger images without anti aliasing on but what would the limiting factors be for images with anti aliasing on? would it be RAM? Video card (doubt it), processor?

What are the best formats for exporting quality images? jpeg? tiff?

Thanks,
Scott

otb designworks · 3 Jun 2008, 12:41

I always export all of my images at very large pixel sizes, but without anti-aliasing. You can then use Photoshop, or similar, to downsize the image without resampling. This will give you beautifully crisp line work and will be much superior to the quality of an anti-aliased image.

I make a lot of HD movies from SU animations. HD (720p) is 1280 x 720. I export all my images at 2560 x 1440 and use FInal Cut Express to export out at 1280 x 720. This gives a very nice quality.

ScottPara · 3 Jun 2008, 12:48

Thanks Chuck. I knew I could downsize them in external apps I was just wondering what was the cause for the error or what the limiting factors were.

Scott

otb designworks · 3 Jun 2008, 12:53

I'm not sure what SU's limiting factors are, sorry.

I do know that unchecking anti-alias will definitely shorten your render times, which is always a good thing.

Alan Fraser · 3 Jun 2008, 13:03

Scott,
Jpegs are generally fine for something like a digital photo which has plenty of detail and texture...as long as it is set reasonably high up the quality scale (about 70% or more). SU renders on the other hand are full of relatively flat colour and thin edge lines, both of which you usually want to preserve. You can do this as long as you set the quality at about 90% or more (at 100% you have no jpeg compression at all, so the quality and file size are identical to that of a bmp file...no jpeg artifacts, but mucho megabytes).

As Chuck says...if you are able, export at a higher res than you need (without AA on) then resample back down in Photoshop. This is actually both faster and better than exporting at the desired res in SU with anti-aliasing on.

If you need the best quality at a hi res then export to Tif format. This is non-lossy (unlike jpg). This, in turn, means that you can post-process away and resave however many times you like and the quality won't deteriorate. With jpg on the other hand, you'll lose a bit of quality each time...more, the lower down the size/quality slider you save each stage at.

SU doesn't seem to have any export compression dialog for tiff files. This means it will export them completely uncompressed...so they'll be huge. All you need to do is open the tiff in Photoshop then resave it using LZW compression. This will make it far smaller but identical quality.
Another non-lossy option is the png format. This will be ok straight out of SU. It also has the advantage of being web-ready...it will display on a web page.

otb designworks · 3 Jun 2008, 13:10

Oh yeah, Alan reminds me that I forgot to mention something important.

I am a fan of the PNG format, and almost every export I ever do is in this format.

I don't think I have used a jpeg, for anything, in ages.

ScottPara · 3 Jun 2008, 13:24

Thanks guys. This is very helpful.

Scott

jhauswirth · 3 Jun 2008, 14:11

Image res is limited by memory. SU doesn't use HW for export, so the graphics card doesn't matter.

tegin · 6 Jun 2008, 22:30

Yeah I guess so. Ram is the limiting factor. Similiar results occured with different computers having the same amount of RAM. It can not be about processor or VRAM.

remus · 7 Jun 2008, 06:16

Is there a limit on how big SU can export (on any computer) then? Because surely as a 32 bit app it can only address a small bit of memory?