Ok. THis is going to get a little complex. I'm trying to do something that has stumped everyone I know. As we know... Photoshop PSD files a frikkin HUGE because each layer is pretty much uncompressed image with an alpha channel attached. Each layer is a 32 bit file, all heaped on top of each other. Jpegs are small, but aside from the lossyness of the format, they have other limitations... NO SUPPORT FOR LAYERS AND NO TRANCPARANCY! So here's what I was thinking.... Since each Photoshop layer is a 32 bit file, isn't there a way to save that layer so the 24bit image and the 8 bit alpha asseperate files, then JPEG both the Image and the Alpha? Now if you do that for every layer, you can make a much smaller JPEG file set that still can be recombined into Photoshop layers for editing. Sort of a JPEGed PSD file? It's still going tobe lossy, but it would be a great tool for 3D texture makers who want the small file sizes, and layers. Any one got any ideas how to do this?

i use tif files, they hav layers, alpha channels AND optional compression.

and tif's under lzw compression are 100% lossless actually.

But even LZW Compressed TIFF's are an order of magnitude larger than a Jpeg.

the whole reason jpegs are small is that they're simple. tiff's r the best soolution u r gonna find, unless u saved each layer and each alpha channel into a differemt jpg.

"...unless u saved each layer and each alpha channel into a differemt jpg." You got it! I'm trying to save each layer, and it's alpha seperatly. JPEG them, and let the user recombine them.

The JPEG2000 spec apparently has 32bit depth, alpha channels, animation and superior compression. Whether it actually made it to reality is another matter - I'm still waiting.

Yeah. I want something that will actually work. :-p I wish Adobe would step up with a Jpeged PSD format.

I doubt they will ever do that. Bottom line is, JPG is a cheesy, amateur format for quick images. PSD is a native format for accurate work. You cant have your cake and eat it. Sorry Mate.

JPG is a lossy format... but it's far from cheesy. A high quality JPEG is still much smaller than any competing format for delivery of things like textures for Poser. The only problem is preservin the transparancy of layers somehow.