BC,

I shot these on a Canon D60 (6.3 mega pixel) with 28-105 lens. The files were set to max jpeg resolution which usually gives you a hefty pic of about 2.5 to 4.0 megabytes depending on detail. I also use a canon EOS300 for film which I scan in to give a similar size picture. I then use Photoshop Limited Edition 5.0 as supplied with the D60 & also the scanner.

I have experimented with various ways of reducing the files to an acceptable size whilst maintaining quality. It would appear that to retain sharpness you need to reduce the size of the picture by fractions that are easy for the software to “extrapolate” or divide up the pixels. e.g reduce it to a 1/4 or 1/8.
So a 1280x 800 picure would be reduced by 1/4 to 320×200, therefore the software has a nice integer of 4 to divide everything by. I think that is how it works & it would appear to work most of the time.
You can also play around with the dpi of the image as well.
I then use the jpeg compression to further reduce the picture size. You can use the sharpen tool to get the sharpness back, but I do not like using this as it looks too false, though I did use it on the one of the unit badge under the cockpit.
Once saved, I do not close in the software package as it retains (& should in most other photo packages) the original compressed image unless you reopen the image from the directory. Check the file size in windows explorer. If the file is less than say the 100k for this forum, you can resave it at a lower compression (higher quality). Repeat this process until you get the file size you want, i.e. just under 100k. Only then close the photo you are editing.

One thing to note is that the amount of detail in the shot complicates the issue. The photos of the Danish Hunter were not to bad to reduce with the basic colour, the photo of the underside of the t-bird was a bit more of a challenge, that is why it is slightly smaller than some of the others.

HOWEVER, remember you can not uncompress a Jpeg. To avoid mistakes I have a master directory with all the originals, then have a working directory to store copies of the photos in for size manipulation etc.

Basically you need a methodical approach to experimenting with each of the variables to see how they effect quality. It is still a bit trial & error at times. Don’t give up though.

One thing, we are lucky on this forum, I go to a motorsport one that limits the size of the photos to 640×400.