Read only view of image data type is too small

[chrisala]

Eg. the ESP form is using the image data type for the regeneration output.
In read only mode, the image thumbnail is very small (25x20 pixels).

[chrisala]

This appears to be because the image is rendered in table, and there is a function that scales the image to the size of the container (which is small!). We probably need to allow a minimum size for this case.