Arm length for macro

Hi guys,

On my last trip, I used an 8 inch arm on each side of the housing. I have found it very difficult to use my strobes, for they always appeared in the font of the port, increasing the capture of backscatters. Am I right ? Or there is nothing to do with that...

Why should we not place the strobes further in the front of the port ? Or should we ?

Please I need some feedback to decide whether I should buy smaller arms such as 5 inch ones.

Cheers

Daniel

The correct placement of the strobes (with any type of underwater photography) is so that they meet at the subject and not before. i.e. they just light up the subject and what's behind and not anything in front of the subject. That way you aren't lighting up an particulate matter between the port and the subject.

When you say "appeared in front of the port" do you mean they were visible in the shot? If so, you definitely have them wrong.

I've always found making strobe placement adjustments much more difficult with a single arm segment, especially for macro. I've used a combination of arm lengths in the past, but have now settled on a pair of short (~6") arms for each strobe when shooting macro. Since you already have 8" arms, you could just add some shorter ones, but I found when I was using that setup the longer arms would sometimes make it hard to position the strobes beside the port for extreme close-ups. However, they were handy when trying to shoot something bigger at a distance, say a meter or so, and get it well lit.

I use two arms on each side. They "articulate," which allows me to pull them back flush with the front of the port, or push them way out in front of my port (closer to the subject) when I am shooting a larger subject with my 60 mm lens. I find that the closer the strobes are to the subject, the less chance for backscatter, and the better light/colour.

I use an 5 inch ulcs arm on each side for 60mm or 105mm. I also use 8 inch on both side but found the shorter one much easier to adjust flush to the port, next to the port or above the port. Sometime fully stretched on both side for wider coverage. I think it also depends on the housing you use. Like the Ikelite has that 2 giant handle bars which is actually a couple inches away from the housing while other housing have the ball sitting right on top of both edge in the housing which could make a different possibily.