Positive Buoyancy Strobe Arms

I'm about to add a 2nd strobe to my setup - currently Ikelite housing for D300 with 1x DS125. [wonder if they can ship a new DS160 to Kuala Lumpur in a few days ]. I'm toying with getting ULCS bouyancy arms to offset the slight negative bouyancy of the setup..yet the problem is depending on whether I use the 8 inch dome port or a smaller flat port, the buoyancy obviously varies with the choice of ports (assuming housing and arm buoyancy remain constant).

If I go with buoyant arms together with the 8 inch dome port will I be diving with a bubble in my sweaty little paws. I notice a difference normally between using the dome port and a smaller flat port and I don't want to overdo it. Maybe I will answer my own question here and go for neutral buoyancy with the flat port and put a small weight intot he base of the Ikelite tray when I use the dome! What are the views on arm choice ?

Steve

I've recently got some StiX medium and Jumbo floats for ULCS arms along with a float belt:

http://www.4gdphoto.com/catalog/index.php?...amp;cPath=11_18

The floats can very quickly added/removed from my ULCS arms to achieve different combinations to adjust buoyancy to my requirements. Individual floats can also be removed very easily from the float belt to adjust buoyancy as well.

I was going to do a quick thread about this. I went out with my heaviest set-up and a StiX set up.

D200

Aquatica Housing

Glass Flat port

2x extension rings

Nikon 105VR

Nikon Teleconverter 1.4

Backscatter MacroMate

Hartenberger Nano Focus light

2x Inon D2000 strobes

With all that I used the following StiX floats:

FB-10 Float belt

2x6"arms. Each arm had 2 of the new Jumbo SX150 floats on it and one SX95float

I put the Hartenberger on a 4" strobe arm with 2x SX95

So that is a total of 4x SX150, 4x SX95s and the FB-10 Float Belt.

With all that the housing was still about 3lbs negative.

I was going to do a quick thread about this. I went out with my heaviest set-up and a StiX set up.

 

D200

Aquatica Housing

Glass Flat port

2x extension rings

Nikon 105VR

Nikon Teleconverter 1.4

Backscatter MacroMate

Hartenberger Nano Focus light

2x Inon D2000 strobes

 

With all that I used the following StiX floats:

FB-10 Float belt

2x6"arms. Each arm had 2 of the new Jumbo SX150 floats on it and one SX95float

I put the Hartenberger on a 4" strobe arm with 2x SX95

 

So that is a total of 4x SX150, 4x SX95s and the FB-10 Float Belt.

 

With all that the housing was still about 3lbs negative.

Wow..I just calculated the weight of my setup: Ikelite house, flat port, D300, 60mm macro lens, 2 x Ikelite Ds-125, ULCS arms/clamps. Comes in at a tad over 7kg...Now to jump into the pool when I get home tonight and borrow the wife's scales to see what the in-water weight is and how much bouyancy the ikelite housing gives with the flat port and the dome port.

I wonder if there is a special gizmo for temporarily making the rig weightless as it is passed fromt he water up to the dive boat captain... I need to learn Bahasa Malay for .."grab it by the handle please..its heavy!"

It will be slightly less negative in salt water.

I can vouch for the Stix floats and arms. I've 6" & 9" arms, both with 9oz & 11oz floats respectively. I had my hesitation in the beginning, though I'm a total convert now. I've had the float down to 60m and they seam to handle that depth, albeit with a bit of compression but then return fine.

My Aquatica + 2xDS125s with the 6" arms is negative, but not by much. With the 6" + 9" arms and dome, it is near neutral but still just negative.

The arm balls are made of some super plastic and haven't shown any sign of wear. Been using them with Aquatica and Ikelite arms, works a charm.

5D in Aquatica housing with Aqua View Finder, 2 X DS-125's, 5 X 8 ULCS, combined with four jumbo floats, regardless of lens and corresponding port, still substantially negative... Maybe the float belt for ports will be next move...

5D in Aquatica housing with Aqua View Finder, 2 X DS-125's, 5 X 8 ULCS, combined with four jumbo floats, regardless of lens and corresponding port, still substantially negative... Maybe the float belt for ports will be next move...

Just returned from a weekend diving in Krabi, Thailand. My setup was around 1kg negative, even with ULCS float arms, so additional bouyancy is my next step. I may try to improvise something along the lines of the float stix - I have a few ideas, so will keep you posted. Am thinking of putting bouyancy rings around the strobe housing to give better balance to the rig, especially for wide angle work. Might keep me busy on Saturday morning : D

Just remember, the Aquatica AD200 is far more negative than the Ikelite. The AD200 is probably the most negative housing I've used, while the Ikelite is the least. I switched off housings with my buddy in order to change some camera settings and she started sinking fast and I started my ascent pretty quickly. That's with Stix floats attached all over the place.

I would recommend using the floats on your current ULCS arms. You can tweak it to just what you need and you can adjust it for each port setup.