Jpeg versus Tiff or maybe a Gif or pehaps a Bitmap?? What do you use the most?? Obviously Jpeg loses quality with each re-save. I hear the standard between Macs and PC's is a Tiff, and that a Tiff "never" loses any bit of quality, no matter how many times you re-save it. It makes for pretty darn BIG files though. What is YOUR say on this topic?? Do all of you have a standard that you use?? ~3D ;-)

For the web - .jpg all the way, unless its a pict for a web site on a patterned background, then I go with a transparent .gif. For personal use, storage, etc. .Tif because no loss in quality, and I have a burner so size really isn't an issue. :) -Trav

Hello, I always save my projects in the native .psd photoshop document format. This is always helpfull in the future for editing, it saves the layers and channels. If I want to output a image I use the Save a Copy option and then convert it to whatever format I want. Tiff is good if you need to have channel info inside your file, Tiff can compress the alpha channels. Another advantage for Tiff is that it travels from Mac to PC rather well. JPG is good for web images, I always flatten the image and delete alpha channels that the JPG will not need before Save a Copy. The only time I convert to Gif is when I need a transparent color on the image or want to animate the Gif. Saving as Gif turns the mode into Indexed color that only has 256 colors so this is a given. If your file has a lot of one color, like say a high percent of blue, select the majority of the blue before you convert to Indexed color. This will force the new 256 pallet to use the blue as the major shades. Then you could save to Gif. I sometimes get better results this way. Serpent

If it is downloaded, it generally comes in jpg which is nice for storage, but large files are unstable in an "as is" form... Because of the heavy "parsing of data", the least little screwup renders the file unrecoverable... I find increased stability through the use of Graphic Converter (it accesses these "raw" files far more easily and trouble free, especially large jpg files), and doing a "Save" to give the file a picture icon renders the file far more stable... If the file is to be manipulated, it MUST be from then on stored in a larger file format to retain detail... TIFF is Ok, but I prefer PIC (Macintosh) so that I can scan the library with one of a number of programs that don't recognise TIFF PowerPC

I choose jpegs every time. I've never yet seen one lose quality. But then, I stay in PSD until I'm finished working on the project. And for any kind of print work you always want to save in PSD so you can access not only the layers but the RGB layers. I really don't care for tiffs at all. Just a quirk. To me, tiffs are exclusively for line art.

Bonestructure, you are quite correct... My comment is wrong and was written in haste... Detail is certainly retained in jpg... What I have experienced however is the loss of the file itself due to some slight corruption... It doesn't happen to me in PICT format which I can always recover with a bit or two corrupted

hmmm, I have yet to have a file corrupted on me. I save zipfile backups of all my images, but I haven't ever had one corrupt. Is there something wrong with your computer? Are you saving images on floppies and maybe need a new floppy drive? There's no reason for a file to corrupt under normal circumstances. I have a CD writer, though I have no money to get CDs at the moment, but I'd save all my graphics files on CD if I could.

Corruption comes from inadequate memory (and, for a while, a bad RAM chip) and pushing it to the limit... then when something "squirrely" happens, having to go through checking and repairing the catalog files, etc. It all seems to leave its share of scars... Nothing that throwing a few handfuls of money under the hood wouldn't fix... The worst that has happened with PICT format is doctoring a line strip or two... A JPG file sometimes fails to be recoverable at all with whatever program I attempt to resussitate it with... I live with it; I use jaz and external SCISI drives both for backup...

I always save and keep a "master" image in Photoshop format, to maintain layers and channels - it's crucial for re-editing later on. When I need to share the file in any way, I save a copy to a minimally compressed jpg. Personally, I DO see a quality loss, even in first generation jpgs. Most often, the compression artifacts appear in solid colors, near a border with a different color. Text also doesn't compress very well. Anything that's had a "noise" filter run on it won't compress very highly and loses detail. I usually have to ask others if they see the degradation. They usually don't. I guess I'm just very critical about my images. I think that comes from my photography background. I've been known to re-print a photograph in the darkroom a dozen times until I'm happy with it. Similarly, when working "digitally" in Photoshop, I'll output several different resolutions and compressions and scrutinize each one to no end... Maybe I should seek help? -sk

Hi Folks! Since I often use many of my renderings for multimedia as well as still images, I usually save two versions--one in native Photoshop format (so i can edit the layers later), and one in pict or .pct (I'm on a Mac). Newbies may not be aware that images intended for printing to hard copies need to be saved at 300 dpi or more, while media images are fine at 72 dpi. As such, pct or bmp formats are better for images that I know are going to end up in a PowerPoint presentation or such, while print images are usually saved as tifs. When to use gifs has already been mentioned by others. I'd also like to pass on this information to newbies who might read this thread. No matter what file format you ultimately save to, one should almost never process the only version of an image you have; it's better to experiment with a duplicate. Every semester I have at least 2 or 3 students who learn this lesson the hard way--but they only need to experience it once to appreciate its value. Peter (Dr Zik)