[Plugin: JJ NextGen JQuery Cycle] prevent stretching portrait photos

The problem: portrait photo’s are stretched to fit the slider, but this is very ugly. So i want to center it, and for example keep the height as an aspect. The slider is 275 width (fixed).

I tried several opties, but it just don’t work out for me.. This is my code now:

[jj-ngg-jquery-cycle gallery=”” width=”275″ height=”180″ speed=”1000″ timeout=”3000″ fit=”0″ center=”1″]

Any ideas?.. thnx in advance!

http://wordpress.org/extend/plugins/jj-nextgen-jquery-cycle/