Red filter

[Interceptor121]

A red filter has to be applied during the dive not later. 60" is generally borderline for filters and definitely not working on stills where you need to freeze motion
Video at 1/50 or 1/60 shutter speed comes out fine

 

[tursiops]

This subject comes up a lot. I've tried to summarize the info here: draft #1!

 

[Interceptor121]

This subject comes up a lot. I've tried to summarize the info here: draft #1!

View attachment 559654

Post process of RAW in the 30-60 ft range is not good. It becomes good if you had a strobe and some light on the subject. RAW does not bring back the red it only rebalances the frame
More importantly for photos if you shoot ambient light at depth you are forced to use slow shutter speeds and this means you can't freeze motion. You need around 1/200 of a second to freeze motion and if you are at 70' this may push your ISO so high that the picture is worthless.

Filters are much more suited to video due to slower shutter speed involved. For photos the use cases are more specific