Hi,
Either colour rendering is somewhat curious coming from an OSC...
What you typically would want to see in a spiral galaxy like this, is;
- A yellowish core (star population skewed towards older stars due to gas depeletion)
- A bluer outer rim (star population skewed towards young blue stars due to gas abundance)
- Red/brown dust lanes
- Pink/purple HII areas dotted around.
- A foreground star field that shows all star temperatures equally (red>orange>yellow>white>blue).
If you'd like to share the DSS or PI dataset I'd be happy to have a look as to what might be going on if it helps. The detail in the PI image is far superior to the DSS/ST image, which similarly concerns me somewhat...