# Photoshop express question: file size decreases when I do nothing! **URL:** \ **Category:** Factual Questions\ **Created:** [February 22, 2013, 3:13am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044 "2013-02-22T03:13:38Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [February 22, 2013, 3:13am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/1 "2013-02-22T03:13:38Z")
Maybe it’s been this way all along, but here’s what I have: I have a 4MB jpeg that I uploaded to photoshop express. When I click the edit option it, it says 4MB. I then do nothing but save it to another file name, and it saves it as a 1.6 MB file. Somehow I was under the impression that photoshop express didn’t ‘scale down’ the size of your file when you uploaded it. Any ideas??? ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [February 22, 2013, 3:54am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/2 "2013-02-22T03:54:59Z")
The compression used in JPEG can trade off image quality for file size fairly readily. Most programs that write JPEGs have something like a “quality” slider for the encoding that varies from “high quality/big file” to “low quality/small file”. Likely when you re-save it, it’s getting re-encoded with a lower quality setting. ---
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [February 22, 2013, 4:20am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/3 "2013-02-22T04:20:05Z")
Hmmm. . . looks like they’ve pulled a bait and switch. My old bookmark did not have ‘mobile’ in it, but the new url does. Looks like they’ve changed it to assume you’re going mobile. ---
**Author:** ![solosam](https://avatars.discourse-cdn.com/v4/letter/s/9d8465/32.png) [@solosam](https://boards.straightdope.com/u/solosam)\ **Post date:** [February 22, 2013, 1:03pm UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/4 "2013-02-22T13:03:19Z")
Every single time you save a JPEG it will go through its compression routine and degrade the file quality. This happens over and over until the file reaches its minimum size (and also worst quality). Photoshop and other quality programs will let you choose how much compression to apply. Regardless, it’s recommended that you edit the file in its native (lossless) format and only export to JPEG when the project is complete. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [February 23, 2013, 7:32am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/5 "2013-02-23T07:32:20Z")
**solosam** has a lock on best practice, but conditions aren’t always perfect. If you are starting with a JPEG: if you think you may need to edit that JPEG again, save a PNG or PSD before saving it as a JPEG. And then try for a slightly larger JPEG than the original to minimize quality loss. Any time you want to edit the image, edit the PNG again, and then save as a JPEG again. That way your JPEG will never be worse than after your first save. That’s assuming the OP wasn’t just trying to make a copy, and just used a no-edit save as an example. If you are trying to make a copy, look for a method to do that directly. Only use the “save as PNG/PSD and convert to JPEG” workaround if you have to. I personally would rather reupload the file under a different name if I had to. Well, if I wasn’t stuck on dialup for the time being. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [February 23, 2013, 10:04am UTC](https://boards.straightdope.com/t/photoshop-express-question-file-size-decreases-when-i-do-nothing/651044/6 "2013-02-23T10:04:09Z")
> [@solosam](#): > > Every single time you save a JPEG it will go through its compression routine and degrade the file quality. That’s not true for every program. Some (notably IrfanView) allow some basic operations (90-180-270 degree rotations and cropping) without recompressing, and therefore with zero JPEG quality loss. Still, your advice is good. Only compress to JPG at the end of a long string of edits.