Your "I presume" needs clarification. What exactly are Costo going to do for you with your photos?
I've had a quick look at the Costo web site, Costo Photos, but I cannot navigate much further without signing up and logging in.
I don't know much about Tiff images, but BitMaps, .bmp , have much better resolution than JPEGs, and do not lose any detail. JPEGs are compressed, and so pixel resolution is lost and quality is poorer. That's fine for most web site images, but I am not sure it is good enough for photos. But the trouble is, as you rightly point out, BitMaps are considerably larger than other file formats, and so take longer to upload. Some web sites would not accept uploading bitmap quality images.
Does Costo give any guidance on this?
Also I am not sure what you mean about converting from PDF format. PDF are text files and can have images embedded in the files. Are you able to extract these photos from that PDF file?
Mark
I was sent my wedding invitation that is made up of one background photo, some smaller foregound photos and some print that I need to convert to a different format to upload to costco online photo shop where they will print the invites on a commercial printer, I presume.
The current image is formatted for 5x7 and is 7.76MB in size. Right now I am looking at going with BMP due to its large size (9+MB) and pixels (2100x1500). Is that the best choice?
What would be the best format I should upload the image as?
I have seen several different possibilities such as my choice of BMP but also read about TIFF and JPEG but don't know if converting from a pdf format to one of those would cause any quality loss/distortion.
Please help! This is my wedding invite I'm discussing! Thank you!!

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