Reducing file size but keeping physical size

I wonder could anyone tell me is there a function in photoshop cs3 that will reduce the file size of a photo without affecting the physical size of it, i know macromedia fireworks can but thats no help to me unfortunately...:mad:

hi,
a couple of common ways to do this...

1. if it jpg is your format... by using your file>save for the web
you can change the compression, which also effects the quality, you can increase the compresson and get a small files size.. but be carefully the higher the compression the more loss of quality....

2. another possiblity to look at... is the dpi setting.... image>image size
if your current dpi is about 300 , going to 72 will result with smaller files size,, but that may effect your printing quality....!!

3. now if it a gif format.... if you only have a few colors in it, instead of saving it it as a 256 color gif file, you can save it maybe to 128 or 64 color or less.... and that done in file>save for the web.. this will give you a smaller file size ...

neilbjmurphy said:

I wonder could anyone tell me is there a function in photoshop cs3 that will reduce the file size of a photo without affecting the physical size of it, i know macromedia fireworks can but thats no help to me unfortunately...:mad: