This is the tutorial for optimising jpgs using adobe photoshop.
The following related tutorials are available:
Optimising jpgs may seem less important than optimising
the often much larger animations but on a board where there could
well be 25 jpgs it's still best to compress them as far as possible.
Luckily it is also much easier than compressing animations.
Step 1 - Image size
An appropriate image size is all important in a picture,
there is mo quicker way to arouse the ire of the b3ta message board
than to post an 800x600 paintmash at full size. As stated in the
FAQ posts larger than 280px wide will be too large for the frontpage
and since there is a particular thrill in seeing your post there
you will probably want to obey this.
On the otherhand since with many posts you aren't
nessecarily aiming for the frontpage posts up to around 450px wide
can be acceptable if the extra size is nessecary for effect.
Step 2 - Blurring
As i stated on the previous page, jpgs like smooth
olour curves and to this end one easy way to reduce the size of
a file is to selectively blur those regions of your picture which
do not require detail (i.e. the background and margins). This need
only be done lightly to have a noticable impact on file size.
Step 3 - Export optimisation
This is where the most significant savings in terms
of file size can be made. To optimise the image go to save for web
in the file menu:
When you click on this it will take you
to the optimisation window which contains the export settings:
Of these settings we are most interested
in the quality adjustment. This defines how closely the jpegs colour
curves will match those in the original image. Typically I would
have this set to 30 as i feel this provides the best size:quality
ratio however for larger images i might turn this down to 20 or
lower. The blur tool is useful if you skipped stage 2, it adds a
gentle gaussian blur to the whole image to smooth out colour curves.
This is useful in larger images however i tend to favour blurring
by hand as it allows you some control over which details you wish
Good luck with your optimisation, if
you have any further questions on the subject e-mail me and i'll
be more than happy to attempt to help you.