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BadMange
12-19-2004, 11:27 PM
I'm using CS on XP Pro, 1GB RAM. My Samsung (5.0 megapixel) camera is not supported by the RAW format, and are in JPEG format on my memory card. After downloading images to my computer, I open them in Photoshop to rotate and re-save them, and they are a LOT larger. Why does this happen, and how can I rotate the images 90 degrees, save them and have them stay the same size?

Some file info: All camera images are 2592x1944. XP says that each image is about 2.25-2.35 MB in size, but when opened in Photoshop, they are 14.4 MB. Using the Image Size tool, the resolution is at 96ppi.

I've experimented with different JPEG quality settings and can't seem to figure out what is going on and how to fix this problem. Any help is greatly appreciated!

-Bad Mange
halo
12-19-2004, 11:47 PM
Its not a fault or a problem per se.

JPEG's are compressed (with detriment to the original image), so when PS opens them it shows you what the file would be saved without compression say for instance as a TIFF because PS doesnt work with compression on the file when its inside PS because most compression methods that can get small files damage that file.*
JPG's have different compression levels, cameras tend to compress images quite hard making small files with some noticable loss, so if you want to save them out to the same size save them at the suggested JPG level. PS will also add preview and icon and an ICC profile, which can make the file larger than the original as well.

* for the tech heads out there, AFAIK PS does compress the data it works with in ram/scratch but in a loss free manner thats efficient for PS to work with. Adobe used to ship a plugin to turn it off, but as machines became faster the processing overhead became so slight the benefits in keeping compression were considered redundant.
BadMange
12-20-2004, 02:42 AM
Ah, I totally understand it now. Thanks for the explanation, halo!
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