Basic DW MX question - pg size

hello all
i’m just trying to make a page for an image of mine in DW MX. The image is 340 x 510 pixels. I tried to make a page that size by editing document sizes and minimizing the page then applying that doc size…But when i tested it firefox and explorer it doesnt open that size…it opens bigger.
you can have a look at
http://www.studiosamsara.com/gallery2.htm

the image i’m testing is called ‘Bulbul’ it’s the bottom one on the right.

Cheers, Samsara.

select the link on your main page, go to behaviours, click on the + sign. click on "open browser window. select your html page and set the sizes…

Thanks Kallisti!!!
i knew it was almost embarrasingly simple to ask that question…but i needed to know, i’ve been looking at DW help for a long time and just couldnt find it.
Samsara.