Low Vis Pickle

[IwakuniDiver]

Hey everyone.
I seem to have myself in a bind. I have written an aritcle for a dive magazine about a WWII wreck that I have been diving. The article is all finished, turned in and the magazine is very interested in publishing it.

Only problem is that all my pictures of the wreck are completely dreadful. The area that the wreck is in is particularly famous (notorious) for having poor vis (10-20feet) and the water is a dark green in color. Very similar to Puget Sound. Take into account that the wreck is in 130fsw, it's VERY dark down there so an external strobe is a necessity.

To avoid comments like "your camera sucks" and "buy this $5000 camera" responses, I'm not going to go into what kind of camera I have, all I'm going to say is that it's digital. I came to the realization long ago that I am a diver, not a photographer.

Here's my problem, my external flash generates crazy backskatter down there but it I don't use it, I have black pics. The top of the wreck is at only 50fsw so I can use ambient light there but taking pics of the bottom of a ship's hull is kinda boring IMO (she's inverted, port-side up). I'm fairly inexperienced in wreck photography so what kind of feature or angle should I go for?

I'm going back in a week for four more dives so any advice on low-vis photography would be greatly appreciated.

Scott

 

[SeaYoda]

How far away from the camera lens is the external strobe?

Does the internal flash fire - if so, is it blocked in any way?

Where do you point the external strobe?

 

[mikerault]

Use a diffuser on the flash and, this is a reach, try a polarizing filter to restrict the direction that light can come from that enters the lens. These will all lengthen the exposure time so be sure you are rock steady. What post processing are you doing to the image?

 

[parabolic]

It's hard to tell what type of deep-water photo you want, just a strobe-lit shot of something on the hull (with the camera angle about horizontal) or a close-focus wide-angle photo with part of the hull illuminated in the foreground and some ambient light in the background. For the former alternative, to minimize backscatter use the longest strobe arms you have, and if you are using one strobe place it directly above the camera pointed straight ahead (parallel to the axis of the camera). Do not tilt it down. Use a relatively wide aperture (f5.6 or f4) and a low or medium power setting on the strobe. If you are using two strobes place them to the side and aim them straight ahead, as described above. For a CFWA shot, with the camera looking upwards, you really need to meter the negative space (the water surface), select the proper aperture and shutter speed for the background, and adjust the strobe power settings for the aperture you select. The shutter speed is irrelevant for the strobe exposure. That's about the best I can do given the info you provided. Good luck,

++Ken++

 

[Warren_L]

Those conditions sound very similar to what I routinely encounter here at home. Typical viz is about 20 ft or so, with lots of crap in green water, and dark at deeper depths. What Ken describes sounds like a good way to go. But to add to that, really only longer strobe arms will help to minimize backscatter. Since you can't control the quality of the water (unless of course there is silt created by divers, then you just have to go when there are no other dive groups around), you need to extend the strobes far enough off the camera lens so that the illumination of the particles by the strobes is not reflected back to the lens. For the conditions around where I am in the great lakes, I would suggest a 2 ft minimum length. More if possible. It might sound a bit extreme, but I've experimented lots with the conditions around here and I've found that for me, about 3.5 ft works well.

 

[StevenB]

If you are after a over all shot of the boat, go as wide angle as you can and get as close as possible. Less water between you and the boat will help the strobes, and reduce amount of backscatter between you and the object.

Steve B

 

[torrey]

Just out of curiosity, would a tri-pod on the floor, no flash, and long shutter-speed work? Assuming there's no fish in the way, of course.

 

[IwakuniDiver]

Great ideas and tips guys thanks!

Since I will be going back to the wreck next weekend I think the first few dives I'll try with a diffuser and close if the particulate matter in the water is bad. On the second day, I'll use a longer strobe arm (that I'll have to fabricate somehow.)

and just so you guys have an idea of what I'm dealing with, here's prime example of what I'm dealing with here. This shot was taken fairly close yet the quality is awfull.

This is a shot of a 16" main gun at 128fsw from about 3 feet away.

This is a shot of some valves inside the port-side passagway under the main deck.

The white (whale sperm we call it) is everywhere and has made photography a nightmare.

Scott

 

[Warren_L]

That's what I'm used to as well. A lot of my shots were turning out that way, and really the best thing to do is to get nice and close and have the strobe further off the camera body. I am unfamiliar with your particular camera, but I do believe the strobe arm is fixed, but if there is any way to remove the strobe from the arm, you can always hand hold it or have someone else hold it for you. I would move the strobe further first, though.