It seems like the image is still being compressed.
Here's a comparison of your version of the class picture:
As you can see a lot of detail has been lost. I'm not quite sure how to solve your issue, as Phieni (The artist of our comic) is asleep and my knowledge of photoshop and other similar programs are quite limited.
Since it had moved on to our turn to add a character to the photo we used Aqua03's image instead of yours as yours was still compressing the image and had a lower resolution. When we added Eleanor we also added your Rocky at the same time. We did this because we didn't want to keep bothering you by asking for the resolution to be fixed.
The image quality of the class photo should be the same as Aqua03's now. Unfortunately the image has gotten too large and exceeds the forum's image size limit, but you can see it here.
However, if you want to keep trying and upload your own version with the correct resolution and no compression, go ahead. We'll wait and add our character again once you're done!