Hello all. I'm new to the forum and new to digital imaging. I have a new digital camera and I use Photoshop Elements 2.0 for enhancing my photos. I love it! Please bear with me as my thoughts are scattered. I read from a link posted in this forum that when making changes to pictures not to do so in JPEG format (that I would tend to lose more data).

Question1: Should I convert to .TIF format and make changes and re-save to JPEG? The pictures were taken at highest possible JPEG quality with Olympus C-765.

I did an experiment with a JPEG photo. I only performed two simple passes on the photo with each experiment. Auto level and custom filter. Then saved as JPEG at highest possible quality.

The first was performed with no layers. Just auto level and filter.
Results: File size 3.176 MB and 279928 unique colors.

The second was one layer for auto level and another layer for filter. Flatten image.
Results: File size 2.434 MB and 258024 unique colors. (I couldn't understand the difference in file size and loss of colors)

The third was opened as JPEG then saved as.TIF. No layers. Auto level and custom filter. Saved as JPEG.
Results: File size and unique colors identical to the first.

Question2: Which should I be doing? First, second, or third and why the extra loss of data when using layers?

Should I be doing something else entirely? I've doctored over 200 photos (always retain the original) and I'm learning more all of the time. Please help me. :classic:

Hi Toddmt and welcome to Retouch Pro. I am an amateur who lives out in the country and takes a lot of photos. How I deal with my pictures is the following. If I am taking serious photos for possible printing I use the Raw Format in my camera. Each Raw format photo takes up a lot of camera memory. For more casual pictures I use fine (or high quality jpg format). After shooting, I put the photos in my computer and use a database (extensis Portfolio) to manage the pictures.

I back up those pictures. I put the back up on an external hard drive or burn them to a dvd. These pictures I do not mess with in any way.

To work with some pictures I will copy the original. If its going out to e-mail I downsize them and use the save for web feature (in Photoshop and maybe in elements.)and save them as jpg and mail them out.

If I am going to process them like work on curves, levels, etc. I save them in photoshop format. After I am done playing with the photos it depends. If I may go back and work on them some more I'll keep it in photoshop format.

So for serious photos I go from RAW to photoshop format. Adjustments like lightness can be made with the image in RAW before opening in photoshop. I save these in photoshop format.

For casual pictures I will fiddle with them and resize them depending what I am going to do with them and save them in jpg.

If you shoot jpeg the damage has been done. The problem with JPEG is compression, and lossy compression at that. I'll echo what Phil said, it it's important shoot in raw. Once it has been compressed, if you convert it to a tiff, it will "render" the compression into the tiff, so there is no gain there. In fact when a file is open you are working with the equivilent of tiff quality (three, or four, uncompressed channels.)

Michael

P.S. I have a Nikon D70 and it has the option of saving both the raw data AND a low quality JPEG. It's handy because I can open all the pictures in jpeg format for previewing purposes to get an idea which ones I want to use and I don't have to wait for the (much) larger raw files to load.

Hi Toddmt,

Like the others, I take important pictures in Raw mode. Jpg is fine for snaps and web postings.

When saving or processing your pictures, the disadvantage of using jpg is that each time you save there are losses due to the compression method used. Therefore if you make several saved changes, there will be a marked deterioration in the quality of your image.

For this reason, when working on your images, convert to one of the lossless file types (TIFF, PSD). If you must have a jpg image, say for posting on a web page, then do a "save as" on your TIFF or PSD file.

Thank you all so very much for your feedback. It was what I suspected. Hopefully I have a home here and can make contribution in the future as I learn more. Thanks again