Viewing photo attachments - default to smaller view?

When opening an email with photos attached, em Client automatically seems to size the photo view to match the maximum width of my screen.  I find this too large - I just want to see as much of the whole photo as possible - even if it’s smaller.  I know I can accomplish this by using Ctrl± to reduce the size, but I would like to set the program to default viewing photo attachments to a smaller size so I don’t have to use Ctrl±.  Is there a setting for this?

The size of the image is usually specified in the message HTML, or if it is not I believe that eM Client will display it at 100%. Other than zooming there is no way to change that to a smaller size for all messages.