help w/saving in photoshop

[ISI_Stang06]

right before a picture gets saved an extra window pops out w/ a number 8 in quality and a bar to drag in size of small and large, what does this window mean and what do i do in it?

 

[chrisburke]

its because your saving it as a jpg... its the quality.. if you want est quality, drag it up to 12..

 

[ISI_Stang06]

so is saving it in jpg bad?
what should i be saving it in if im posting the pictures in my photobucket and if i plan on printing them later?
whats the effect on the bar w/ the size?
right next to the number it says high, should i change it to maximum?

 

[chrisburke]

saving them as jpg is fine.. its typically what you do... put it to maximum.. you dont always see the difference, as you normally only see the difference when you start printing big prints (bigger than 11x16)

 

[Raze]

Be aware, when you open a jpeg and then save it again as a jpeg, you loose quality each time you open and save.
It's better to keep one as Raw (if that is how it was shot) so you can go back and edit it without loss of quality, or once you open it save it as Tiff or another loss-less image formate if you think you'll open it up again to work on it some more, then save it as a Jpeg for uploading to the web.
So make it a rule to always keep a back-up of the original.

 

[andrew99]

This slider controls how much compression is used when converting to jpeg. Setting it to 12 creates large files but with the best quality. Sliding to the left makes smaller files but reduces the quality. For printing, always use 12 (best quality), but when saving for the web, you can use less (for smaller files that will load faster over the internet). Always keep your originals, though, never over-write them.

Try saving an image twice, once with quality 12 and once with quality 1 (obviously with different file names), then you can compare them.

 

[realitycheck3907]

ISI you can also move the bar while looking at the image and as long as the preview button is checked you can see slight changes in the photo as you move it from 12 to 1 or 1 to 12.

 

[manaheim]

saving them as jpg is fine.. its typically what you do... put it to maximum.. you dont always see the difference, as you normally only see the difference when you start printing big prints (bigger than 11x16)

True, but oversimplifying a bit.

JPEG is lossy compression, which means that when you save it, the tool (in this case Photoshop) will decide what data you do not need in the image, and toss it. Gone. Forever.

Now, if you are taking pictures in JPEG mode, you may not be losing THAT much, but if you make corrections on photoshop that puts certain data out of the visible range, and then save it, you've lost stuff. (taking pictures in RAW avoids this problem as you have ALL the data when you made the capture, and you can always go back and re-do it if you didn't like your edits)

Things like TIFF, PSD and PNG have lossless compression capabilities so you do not have this problem.

One very good thing to do if you shoot in JPEG is to always open your original and save off the changes you have made as a DIFFERENT file... that way you're at least not losing even more data than you already lost at capture,and you're not further mangling the image by repeatedly opening it and saving it over itself.