I occasionally have that happen.

It's usually if the photo's don't exactly fit eBay's minimum requirements.

http://pages.ebay.com.au/help/sell/pictures.html#guidelines

I noticed all yours zoom except for the wedding dress and as it's the only one of unusual size, that's probably why.

Thank you you are too clever...can i change the size as it would be helpful to soom in on the beadwork on the dress...thanks again

I often don't worry about it or take another photo, close up and add it to the listing rather than re-taking all photos trying to get them within eBay specifications.

You could bring them into paint and resize. That can sometimes work but not always. (depends on number of pixels)