I have to say I usually find it much much easier to adjust stuff afterwards on the PC, but YMMV.
Have you already cropped out everything apart from the part which you are interested in? And can you perhaps get away with dropping it into B&W? That’s effectively 2-bit colour and gives an even bigger reduction than going to 8-bit.
Reducing the dimensions of the picture that your camera takes will in essence reduce the detail as well. The jpeg compression algorithm is quite good, and I think you’ll be surprised at how little quality is lost even at the higher compression levels.
Almost any graphics program will be able to resize a jpeg, so try that first.
On the other hand a single picture of 3MB is pretty big and almost certainly unnecessary for ordinary purposes, so adjusting your camera’s settings wouldn’t be a bad idea anyway.
Computer screen resolution is 72 dpi
Regular old Microsoft Paint can do it too. Open Paint>Image>Stretch/Skew>Adjust percentage of pic>Save As.
I’ve had this happen in reverse; opening a large TIFF file in Photoshop, making some minor changes and saving it made the file several-fold larger. After fiddling around with ResEdit (Mac person here) a bit, I decided that it was Photoshop adding a “preview” thumbnail, which for some reason was larger than the base image itself. Deleting the thumbnail made it all better.
JRB
Pardon, but I’ve often wondered where people in India go for tech support. I love this Board.
Adode Express is free and has been well reviewed