All of the images I have contributed to this site have been from PhotoCD. You can have B&W and color negs as well as color slides put on PhotoCD. I have been able to crop some images considerably and still have a high-quality end result. Rejection messages from this site often contain statements about scanner settings. Working from PhotoCD makes these statements irrelevant. Also, recent virus threats have affected JPEG files. If your work is on a PhotoCD, it is on a read-only device in PCD filepack format, immune to viruses. The PCD filepack contains the image in five different sizes. I commonly use the two largest sizes (LARGE=1536 X 1024, and POSTER=3072 X 2048) for the work I have submitted to this site. Nearly all of my color work is from transparencies, consequently you will not find the white marks in the skies of my pictures that are so prevalent in the work of color print shooters.
PhotoCDs are multi-session products with a storage capacity of 100 images of 35mm size. The more sessions on a PhotoCD, the more storage space is lost to overhead. If you visit your developer and submit four 24-exposure rolls of film, you will get all 96 images on one CD. If you bring in 100 slides or mounted negatives, you will get all 100 on one CD. If you have a four-session PhotoCD, each session being 24 images, you may not get all 96 images on the CD because of the overhead. The first session will cost more than the others because you pay for the CD media at that time. The capacities shown above are minimums. It is possible to get around 120 images on a single-session CD, but the operators of the equipment won’t often exceed the published figure of 100 images. PhotoCDs are available for medium-format shooters. If you can afford medium format, you can probably afford the much higher cost of the associated PhotoCD.
On the downside, the employees at many stores know very little about PhotoCD. They will likely be confused with PhotoCD/PictureCD/and other photo diskette products their store handles. If you go to a legitimate camera shop, you should find more competent workers and higher fees. If you go to the local drug store you will be on your own when issues arise. At present, I can gain access to Kodak’s PhotoCD service through a national drug store chain for about USD 1.85/each. It takes about 15 days to get the work back from Kodak. No matter who does the work, you must be sure to submit dust-free source material.
Good luck and good shooting!