jpg file size increase in Photoshop 7

habilis

habilis

Ministry of Re-Education
It's this simple:

• I import pictures (jpg's) from my digital camera.
• I adjust the levels and brightness/contrast
• I resave them, not changing the file name, image size, mode, or resoloution.

The result is that the file size almost DOUBLES.
Typical Example: A 1.4MB jpg, open in photoshop, adjust levels and contrast, resave over old jpg, file is now 2.6MB. If I save with the quality setting at anything less then maximum then I lose original image quality.

Am I missing smeting here? How can this even be possible? there are no new colors or details added. I even tried a test where I just adjusted 1 pixel, resaved, and got the same odd filesize doubling effect.
 
Mine went down. A 300 dpi 2048 X 1536 was 996 kb, to 708 kb and a compression of 9. Thats kinda crazy for such a large file. A compression of 12 is 1.4 mb. Consider the color information may be saved, so the more pixels, the more data information is being saved.
 
Now i resaved the original, NO changes to a 12 compession without the color data, and the file sized jumped to 1.6 mb. Saved as baseline opt, went to 1.5. I'm not sure whats what, maybe photoshop writes information to it for later use, not big deal, you have the hard drive space. Thats like a floppy, and whats a floppy. Digital cameras try to get the files as small as possiblke, and most likely uses a compression less than 12, giving you smaller file sizes to fit on those CF cards.
 
Yeah, you have to use a compression setting of 12 otherwise the image actually degrades slightly. I zoomed in and noticed a very minor pixel change between 11 and 12. It's just plain wierd though that the file becomes bigger. In december I took over 400 photographs and 12 mpgs (works out to about a gig a month). Looks like I'm gonna need a second HD pretty soon.
 
Archive to DVDs, thats what I have to do. I use to burn CDs, after going through 50 cds, i said it's time to do DVDs. The lose in quality isn't that big a deal, at 300 dpi, the eye won't really notice at 9 compression, unless you get in with a lense or zoom it on screen. So hows Cleveland? I think I'm going to head out to Cali after graduation.
 
I'm definately a quality freek. I feel like I'm missin out if I save at anything less then 12.

Cleveland... is COLD. Thats about all it is right now. The snow and overcast makes for taking some nice photos at Lakeview Cemetery though. And I get to spend a lot of time inside on the Mac, whice is fun.

Cali? I'd love to visit there, but the hollywood types really get on my nerves.

Have fun.
 
Yea, the hollywood type i know i'll have get use to. Nothing is set though, Lakeview huh? Thats not too far from where I use to stay. It's pretty much the same here in Rochester, stuck indoors working on this website. I'm editing images for my site, which don't need all the detail PS work since they'll be vectorized, but that easier said.
 
hollywood types? feh... rednecks ;)

i have the same problems, with jpgs, i use a nikon cp5000 and when i resave in photoshop, unless at a pretty low quality setting the file size increases... so i generally leave most pictures alone until i need to use them, the good ones get saved as a tiff :)
 
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