Picture loses quality upon saving in Photoshop CS5
I am using adobe Photoshop CS5, I am transforming my picture into black and white via "Calculations" and then i apply "Shadows and Highlights" filter.
It actually looks very good in Photoshop but it loses its original quality upon saving, slightly but noticeable.
I am using high mode while saving in JPEG.
As others have noted the JPG format is lossy it will lose information with each save, thus each progressive save makes the image a bit worse.
PNG can also be lossy, and it is also "lossless".
- PNG-8 is an indexed lossy format, rather like GIF.
- PNG-24 is a lossless but compressed format, which will make very nice images but the file size is much bigger.
Recommendation / How I work
- I typically start with a JPG off my camera.
- Open the image in Photoshop
- File > Save As > desired file name.psd (PSD's are awesome! They retain full quality and all layering/adjustment info. They're the best for a "working" file. You can make all the changes you could desire and you won't lose any quality. Yes, this will be a very large file, but it's worth it.)
- Continue working/adjusting
- Save the PSD often
- When satisfied with your changes, do File > Save For Web > JPG > select your preferred level of compression > Save button (I recommend JPG for most photo style images since it balances the quality to file size ratio better than PNG. PNG works best with illustraions, it can do photos but that's not it's primary strength, in my mind.)
- Upload JPG to image sharing site of choice. (JPG is the final result because it keeps none of the layering data and is nice and small for web bandwidth concerns.)