When I upload a photo to my blog it shows on my workpage and again on my preview. When It goes to facebook sometimes it shows as a thumbnail next to the post and siometimes not. Also, if there are several photos it pics one. I want them all of the time but want to be able to pick which one.
We cannot control, which images Facebook chooses to display. Please read this entry
Only the first five images uploaded to a post (direct inclusion/gallery/slideshow) will be sent to Facebook. The images size has to be at least 200 x 200 pixels.
To select which image will be used for things like Facebook Publicize, you can use a theme that supports featured images. If a featured image isn’t set or your theme doesn’t use featured images, then the code tries to pick the first image in the post or page. If no image is found, then the blavatar is used.