JPEG Compression - Quality & Size

[Riverlander]

I was reducing the size of an image for the Web and at "Quality 7" it was going to be 350.2kb. I needed it to be less than 250kb so I reduced the setting to "Quality 6" only to see the saved size go up to 257.4kb.

Does this odd increase in ultimate size happen very often?

I re-checked it a few times and got the same results. Eventually had to settle for "Quality 5" (203kb) to get under 250kb. It was the pic of the male in this post
http://www.ausphotography.net.au/forum/showthread.php?t=27214

[I @ M]

Graham, have a look at using a 3rd party program that lets you in put the longest image dimensions and the maximum file size you wish to have.

The program is called BD Sizer, freeware and available at -----
http://www.idimager.com/?page=freeware

I use it, it works and also has the option of installing pre made frame sets with exif captions as well.

[pgbphotographytas]

I use Irfanview to do this, http://www.irfanview.com/ it allows me to set the size and process many photos at once the same.

Paul

[pommie]

Just a small hint for compressing images,
high detail/contrasty area's do not compress very well, try smoothing the sharp/contrasty ground area behind the bird, not enough to take away from the overall image but enough to give a smaller file size for the same compression setting.
A bland soft area will compress more than a colourful sharp one.

Cheers David

[etherial]

I found that using Zoombrowser you click on export (yes not quite the first place you would look) and there is avery good tool for resizing images where you can specify size and it calculates file size for you before you save it. Very useful!