Saving for Web, quality loss or not?

<p>Hi, <br>

I was trying to save a photo file for web/mobile use. <br>

Photoshop said original size is: 56.3K, but Finder read: 92KB<br>

When I Saved for Web, the image in Finder read: 16KB, in Photoshop, when reopened, it was 56.3K again!<br>

When re-saved this new image "Save As" the image went up in size, Finder: 88KB,</p>

<p>I went on repeating this process and 92KB never repeated again, but was steady at 16KB or 88KB in Finder and 56.3K in PS</p>

<p>So, my question is, does the quality stay with the image even if sized (optimized) for web? And what do I loose going from 92KB to 88KB?<br>

If saving for web does not harm the quality, then that would be wonderful for my website/lighter and when opening the sized-for-web image again it wold "get back to normal"<br>

Wondering...</p>

<p>"Save for web" doesn't degrade image quality. Regardless of which way you save, the size of the saved file depends on the quality setting you choose while saving.</p>

<p>so if I choose "maxium/100" then it would be just like zipping/lossless? and when it's opened up again all the details are back/unzipped?? then why did it go from 92KB to 88KB?? Is it because of all the extra data/text?<br>

thanks</p>

<p>What if I wanted to sell that digital image and I didn't want it to look like it's a cheap copy/16K, what would be the simplest workflow??<br>

thanks</p>

<blockquote>

<p>so if I choose "maxium/100" then it would be just like zipping/lossless?</p>

</blockquote>

<p>No, jpeg is a "lossy" format. Each time you save the image, it loses a bit through compression -- not much, but a little. In the "save as" dialog box, there's no point in going above level 10. Levels 11 and 12 will create larger files, but you won't see any difference. In "Save for web," a quality level of 80 is about as high as you'd ever need to go.</p>

<p>I see. I will not be re-saving over and over. I work on RAWs or PSDs and then turn them to JPEG once finished. <br>

But I do wonder if <em>Saving for Web</em> is similar to "Save As", except that <em>Saving for Web</em> is more of a "zip" type of action (as opposed to ridding permanently of details), still preserving all the details and when opened comes back to full previous (as the "Save As"), like a sponge that's been dipped in water, the weight is back, but the whole is still the same.<br>

do you know what I mean?</p>

<p>"Save for Web" only does two things differently than "Save As":</p>

<p>1) It gives you more options in terms of color mapping so that you can optimize for specific platforms; and</p>

<p>2) It allows you to strip out all the metadata.<br>

<br /> That's it. Otherwise, it's just a jpeg saving action and has nothing to do with the details in the photo. You can save at the same quality level with either save method and you will get exactly the same image. So your last comment is wrong.</p>

<p>sorry it's a bit confusing (I shouldn't have used the word "lossless")</p>