Why do pics reduce their size after I edit them on Adobe CS3?

Question

HI, I have been using Adobe Photoshop CS3 in order to fix some underexposed pictures using layers n screen. But when I save those edited pictures their size is lower than the original pictures. For example, from 4.1 MB to 1.2 MB

Is this going to affect the image quality???

Answer 1

If you are using JPEGs, every time you open it and save it you are going to keep losing quality, even if its not noticeable to the naked eye. If you possibly can, try working with other files such as eps, jpeg, tiff...

A jpeg is a compressed file so opening and re-saving is only compressing it more.

Answer 2

Check your settings for saving your photos, are you saving them at 300 dpi or are you saving them at 72 dpi, if you are saving them at a lower dpi, it would explain the loss of size.