Removing a shadow over an image

Hi,

I am creating a website for a client and using the Ascension Theme (this is a theme produced by the host, Good Daddy). I have an issue where I would like to remove the filter (shadow) over the header image. This can be best seen in the link. As you can see the images are the same but the one in the header appears darker that the one in the body. I know this must be controlled by some lines of CSS and I am familiar with writing and changing CSS and also know about all the precautions I have to take like backups etc. I just would like a clue to where I should be looking.

After doing some research, my best guess is that this effect is created by using a box-shadow e.g:

box-shadow: 0 0 10px;

Do you think this is probable? Or should I be seeking out another area in the code to alter?

I’m just looking for clues and best guesses really. All ideas would be gratefully received. Oh, and the reason why we wish to remove it is that I am trying to put a piece of white text in the header and the shadow is making the text illegible.

Many Thanks
Paul

p.s. already contacted Good Daddy about this and they were useless!!!!
p.s.s. not looking for theme support just general advice regarding producing shadows using CSS.

The page I need help with: [log in to see the link]