A friend of mine put together a benefit calendar using CafePress. I sent her 6 JPGs. A couple other photographers submitted images as well.
My photos look simply terrible printed out on the calendar; the other photographs look fine.
I shoot in RAW, and process with LR4. I generated highest quality JPGs, they're 4,000 x 2,600 pixels (approx), at 300dpi. The JPGs are about 10-12Mb in size, each. When I open the JPGs on my monitors, they look fine (2 uncalibrated monitors, 1 calibrated). When I print them at 8x10, the same size as the calendar, they're fine. Suitable for framing.
My friend says that when she opens them on her computer, they're "grainy". She lives across the country, so I can't see what she means. She's verified the size of the images.
Clearly, by the time CafePress prints them, something has gone terribly wrong - it looks like they've printed out a jpg that had maybe 100x60 pixels of resolution. There's an incredible amount of pixelation, and no detail.
I wonder if your jpgs were "too large"? and someone who did not know what they were doing, reduced them in size -- not realizing the ramifications?
I remember a few years ago when my daughter sent some wedding photos to a local camera chain -- they not destroy the images, but they reported back that the files were damaged and to please re-submit. Turns out their printing would not handle over a 5Mb jpeg and treated it as damaged.
For CafePress calendars they state image size, 2300 px wide x 1800 px high with 50 px being trimmed from each side.
I found it very wise to follow their template sizes and use 200 dpi when outputting photos for them. Also make sure that there is no profile embedded and the image is sRGB. Embedded profiles or other color standards cause strange things to happen in their printing process.
Sounds like she saved the files using her email program's or browser's file viewer, rather than downloading the full file and sending it on to Cafe Press. Best to use DropBox for things like this in order to ensure the printer/publisher gets the correct file.
Well, my "friend" is calling the shots. She told me that no other photographers had an issue. I did some checking around, and apparently all the othe photographers have the same issue, and are very unhappy with the results.
After figuring all this out, I offered to handle the process, but was told in no uncertain terms that she is the expert, and does not require my assistance.
Some email programs truncate resize attached images. AOL is particularly bad about resizing or dropping images.
Many mailboxes cannot handle 10MB files. In my case, only my own email account can handle large files and it can't handle extremely large files like those from a D800. I also agree that DropBox or something similar is a better idea.