iPhoto and image size

[csonni]

As of late, I've been downloading images off of my digital camera with iPhoto.  One thing I notice is that the images brought into iPhoto are much smaller in size than when downloading them through Photoshop.  A typical jpeg with quality of 12 is generally 3.5 megs in Photoshop but only about 600 k in iPhoto.  Am I getting lower quality images by going through iPhoto?  Maybe I should download them into Photoshop and then import them into iPhoto?  Any suggestions?

[tacit]

A "typical" JPEG of what size?

For starters, the size will depend on the level of JPEG compression and on the pixel dimension of the image. Your camera already JPEG compresses the image; the size you see in iPhoto is the size of the image on the camera. When you open and then re-save the picture in Photoshop, Photoshop is using better-quality compression--but since the camera has *already* compressed the image, you do *not* get a better picture!

iPhoto takes the picture right off the camera. Photoshop takes the picture off the camera, uncompresses it, and recompresses it. This does NOT make for a better picture.

Also, unless you have told Photoshop not to, by default Photoshop puts a thumbnail preview, an icon, and an ICC profile into the file, making it larger.

[csonni]

tacit, the point you made about PS making some extras by default could be the issue I'm checking into.  I shoot all my pictures on my Canon G1 in the largest and best quality jpeg (not sure of the resolution).  When importing into Photoshop and saving (with quality of 12), the file size ends up being 2.4-3.5 megs.  In iPhoto, the same import (obviously, there is no quality setting available) brings in the file at about 600K.