replacing standard arms with new ultralight buoyancy arms ... yes or no
#1
Posted 10 December 2011 - 03:53 AM
I have what I think of a standard arms setup ... Alu based arms with clamps and joints.
I do wide angle shots so always have a larger port dome which brings some positive buoyancy.
Now I switched to D700 in S&S and have 2 YS250 and consider having same setup with maybe some optional floats if required ... still need to look into it in pool.
On the other side I am considering replacing arms with those new ultralight buoyancy arms.
So what do you people think about it?
Are there any other people with S&S dSLR WA setups with 2 YS250s ... what is your buoyancy experience.
Thanks,
Marko
#2
Posted 10 December 2011 - 06:01 AM
I have a similar setup and I end up using foam floats on my rig when I need the floatation. This is only needed when I have the macro setup or I'm shooting W/A with the little 4" dome on. I have two 8" aluminum float arms but find I rarely use them. I would have them on if shooting big animals in a current. Your idea of getting in the pool to it check out is a good one. While your there play with the rotational bouyancy as well as the normal positive/negative. The 250's and arms can have a combined effect to counter the dome wanting to roll your wrist out of socket. It's a fore and aft thing. You'll see what I mean when you get it in the water.
Have fun with the new rig!
Cheers,
Steve
The Fin Foundation
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Canon7D & 40D, 60mm, 100mm, 17-40L, Tokina 10-17, Nauticam 7D, Sea & Sea MDX-40D YS-250's ULCS arms, Lightroom
#3
Posted 10 December 2011 - 10:49 AM
For example, if I'm using my 8" dome and 10-17 on my Aquatica with two DS-125's, I use two 8" old style ULCS buoyancy arms with 6 jumbo StiX floats (3 to a side). This is just slightly negative in sea water and is very comfortable -- I can hold with one hand easily.
If I change over to the 105mm and flat port I need to add 1 more float to each side and then it's just slightly negative, but very manageable. I like my rig where I can let go of it underwater and it very gently sinks.
I stopped using the larger diameter ULCS buoyancy arms because they just did not add enough. I used to dive an Ikelite housing and it only needed 1 float per side, the Aquatica is quite a bit more negative and makes my arm tired without floats.
Just my own opinion, everybody seems to like a different balance on their rig,
John
Edited by johnspierce, 10 December 2011 - 10:51 AM.
#4
Posted 11 December 2011 - 01:23 PM
Tom
#5
Posted 14 December 2011 - 01:22 PM
http://wetpixel.com/...el-rinse-tank5/
Get the thicker 50mm diameter ones if you need a lot of buoyancy.
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#6
Posted 02 January 2012 - 09:51 AM
#7
Posted 02 January 2012 - 12:36 PM
If all I wanted was close to surface floatation, pipe insulation (40 kg/M3 density) is good. For recreational depths, the Stix will be fine.
· INON Z-240s & Sea & Sea YS-250 Pros
· SmallHD DP4 monitor & NA-DP4. Fisheye Aquavolt 3500s & 7000s
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#8
Posted 02 January 2012 - 01:34 PM
'Home grown' foam floatation is usually useless by 20 metres, especially 'noodles' or similar and Stix is useless by 40 metres. I use the double buoyancy ULCS arms as they remain effective at technical depth and are rated to 100 metres.
If all I wanted was close to surface floatation, pipe insulation (40 kg/M3 density) is good. For recreational depths, the Stix will be fine.
I have to respectfully disagree with your statement about the Stix floats being useless at 40 metres. I have not had mine quite that deep, but I have been down to 110 feet (33.5 metres) with my Stix floats and they are still functioning quite well to keep my setup near neutral; in fact, they don't really feel any different at that depth than they do at 40 feet. I don't know, maybe they really start crunching in that last 7 metres, but from 30 metres to 40 metres is only 25% increase in pressure, yes?
With 6 Stix jumbo floats I can toss my rig up into the water column and it will just gently float downward. The Stix floats are quite different in composition from a pool noodle or pipe insulation -- they are very hard whereas the latter are soft and easily compressed.
I tried out the double buoyancy ULCS arms and they just don't provide enough lift for my Aquatica/Ikelite setup. One 8" double buoyancy arm provides 4.5 oz. of lift. One jumbo Stix float provides 5.6 oz. of lift. I use three jumbos on each side -- there is just no way to get comparable lift from the ULCS double buoyancy arms.
Here's a link to a Wetpixel review on Stix arms done by Cor and Julie where I believe their experience has mirrored my own:
http://wetpixel.com/...-by-cor-bosman/
cheers,
John
Edited by johnspierce, 02 January 2012 - 01:58 PM.
#9
Posted 03 January 2012 - 06:28 AM
I haven't owned Stix floats so I'll bow to your greater knowledge...
I based my observation on two pieces of information; hearsay and when I took a single float to depth the check its propensity to crush. Seemingly after 40 metres was when it started to 'give up'.
I do agree with you that the double buoyancy ULCS arms do not provide the same floatation as the Stix floats at recreational depths though for hypoxic depths, they are presently the only option.
Whilst 'underslung' buoyancy chambers may have the effect of de-stabilising a housing I have noted that some DSLR video shooters are using this technique to lighten their load. I may try this if I can achieve a watertight seal on a plastic tube and end-cap.
· INON Z-240s & Sea & Sea YS-250 Pros
· SmallHD DP4 monitor & NA-DP4. Fisheye Aquavolt 3500s & 7000s
· Zen DP-100, DP-200 & DP-230
#10
Posted 03 January 2012 - 07:10 AM
Edited by NWDiver, 03 January 2012 - 07:16 AM.
#11
Posted 03 January 2012 - 07:20 AM
Another solution that you may want to look into is this inexpensive hard foam material described here and here (among other places I am sure). It is easy to cut and adjust. You strap them to your arms or housing using cable ties. I have seen a few photographers using them tool. It can serve as bumper protection as well, which is a bonus.
Since I have never dove below recreational limits, I can't comment on how those things behave at depth. But physics says that ANY material will be compressed past a certain pressure... for metals, you may have to drill into the planet's core though...
#12
Posted 03 January 2012 - 09:13 AM
I do agree with you that the double buoyancy ULCS arms do not provide the same floatation as the Stix floats at recreational depths though for hypoxic depths, they are presently the only option.
For hypoxic depths the Aquatica float at 1lb. of lift might be an option. Looks to be pretty bulky though.
http://www.bhphotovi...ting_Float.html
take care,
John
#13
Posted 03 January 2012 - 10:04 AM
Anyhow, if it works I will start selling them here branded as AntiBrix floats, and will paint them any colour you like!!!
#14
Posted 07 January 2012 - 12:04 PM
Funny thing is they seemed to lose some of their buoyancy over time, something I discovered by placing an old in water beside a new one. I don't know why this would be, perhaps they absorb/retain salt over time. Anyway, they're cheap enough to replace I guess.
#15
Posted 10 January 2012 - 11:19 PM
#16
Posted 31 July 2012 - 01:11 AM
I can confirm that below 60m (180ft) they becomes like marshmellow
Totally useless for tech diving.
#17
Posted 11 August 2012 - 07:55 PM
My rig is slightly positive less than 10m, but neutral/slightly neg at 30m. Have had them to 50m with no problems. Yes they squish up a bit, but come back in an hour or so on the surface. Very light for travel and versatile to adjust. Don't get the stix arms with the plastic ball arm ends because they get chewed up by the clamps. Go with the ULCS aluminum arms and taylor your floats as needed. A few pros I was with in Lembeh used a kitchen knife to cut jumbos in half/thirds to dial their rig right in, but that is too picky for me.
Good luck.
http://www.matthewramaley.com
#18
Posted 11 August 2012 - 07:58 PM
http://www.matthewramaley.com
