JPEG's & file compression

[MantaRay]

I can't quite get my head around that when I save a JPEG on my computer direct from a camera I end up with a file of a certain size...but if I re-save the picture the file size gets compressed to something significantly smaller. But there are still the same number of pixels...so, "what's that all about" and does picture quality suffer after saving a jpeg for a 2nd time?

[ChuckFickens]

basically... yes the quality does suffer.

Every time you save a JPEG the compression algorithm is run on it to reduce the size, the first time the file is saved you can't really notice any difference, but each time it's saved after that it's compressed a little more so more quality is removed.

If you are going to be re-saving a picture lots of times due to editing it. you are best off to start with a uncompressed format and then just save it as a JPEG when you've finished editing it.

[Tuvok]

take a look at whatever program you are using to edit your image - there will be different options for when saving.

[JessicaEldridge]

No, you can not lose image quality of the JPEG file when you will save the same file a 2nd time but avoid the use of the "Save As" command.