question about digital horizons topic on work flow

[kodachromeguy]

Hi, new here, and to digital photography. I have spent many years with film and now find out of necessity I need to learn digital to continue. I just recently received an older version of Photoshop and am trying to learn the basics. So my question is on point two of the digital dark room photography work flow. Why should I not do things in jpeg? Is this just a way to save guard my work if you have not saved an original on a cd? Or is it more complicated than that?

[rod barbee]

It's ok to work on a jpg, just save it as a tiff or psd.
Jpg is a lossy format, when you save, the image data gets compressed. If you resave a jpg as a jpg you will get more compression and image degradation.

rod

[kodachromeguy]

Should I use Raw then? Or will I have the same problems so it doesn't matter.

[rod barbee]

If you shoot RAW, when you open the file in Photoshop and work on it, save as TIFF or PSD. You can't save over your original RAW file anyway.

[BlackeyCole]

What does that mean? It means anytime you manipulate an image in jpg format some of the original data is lost and to make up for it the program prut in either a solid black or solid with pixel. THis substitution then degrades the quality of the image. THe best thig to do is open th eimage change the file format to a lossless format (tif or PSD as an example) then edit the image and output the image to the format that you require. Then next time you need the image and need to change somethign whether change the print size or change the image it self make the changes sharpen the image and then output the file to the new format. This is the prefered way other wise every time you open the file and modify it then resave it you have lost data two to three times depending on the editing done.