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r4e

Member Since 16 Jan 2011
Offline Last Active Jun 21 2017 04:44 AM
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Posts I've Made

In Topic: Panasonic LUMIX GH5 for underwater video

18 June 2017 - 06:33 AM

Disclaimer: I have no experience of the IBIS in the GH5.

 

However, my former Sony MC50 video camera had an OIS that was able to lessen, but not completely eliminate, the slight swaying caused by fin action whilst shooting video and swimming at the same time. The Sony had couple of settings for the OIS and I shot test videos with various settings before I selected the setting that best matched my swimming style. I once forgot the recording on after a dive and got wonderful footage of the camera being handed over to the boat and then thrown under a bench. Thereafter the OIS kept compensating the rolling motion of the boat.

 

PS. you can also lessen the swaying motion by performing much smaller fin strokes, e.g. modified frog or flutter kick.


In Topic: Aquatica AD500 flash trigger not triggering strobes

17 March 2017 - 07:00 AM

The optical sensor of the Sea&Sea strobes is known to have had sensitivity issues with various electronic trigger boards from different brands. You should try to maximize the trigger light emited to the optical cable, If there are small reflectors in the housing, try turning them into a position which gives the most direct mirrored route of the trigger light. Additionally you could line the top inside of the housing by some tin foil. This helped in one case.


In Topic: Strobes firing on their own

17 March 2017 - 06:47 AM

I guess you are using an Ikelite Y cable to connect from a single Ikelite bulkhead on your Aquatica housing to your dual strobes. A faulty Y cable or bad connection from it to the bulkhead connector could cause simultaneous trouble to both strobes.

 

The next suspect is the internal cabling and bad connections. If the internal cables from bulkhead and hot shoe are connected to a small circuit board via pin-like connectors, try removing and reinserting the connectors. If there are DIP switches on the circuit board, carefully make a note of their positions and thereafter switch them couple of times back-and-forth before restoring them to their initial positions. You can check the (service) manual for the right positions of the DIP switches.

 

Are you using the new Ike TTL circuitry in your Aquatica housing? Perhaps that is misbehaving? If you still have the internal cabling from an earlier housing, you could try direct internal connection from strobe bulkheads to flash shoe.


In Topic: Just getting started...how am I doing?

01 March 2017 - 02:19 AM

If you plan shooting near the maximum depth ratings (of domes), using a vacuum valve system  has its benefits and drawbacks.

 

A vacuum valve will improve O ring sealing on the surface and very shallow waters (less than deco depths). It also will help you to avoid some common user mistakes and might provide some "peace of mind".

 

However, for maximum depths, the partial vacuum (0.2-0.5 bars) will increase the pressure differential and consequently decrease the nominal maximum depth by as much. In other words, the dome might implode 6-15 feet shallower than it otherwise would. Secondly, the valve is yet another protrusion on your housing and thus slightly increases risk of line entanglement etc. Additionally, the valve itself is an additional leak point. If you do not close the valve fully, it might be airtight at the surface, but still leak at maximum depths. Finally, should your vacuum circuit alarm whilst at bottom, apart from turning the housing to face downwards, there is not much what you can do until returning to surface. With one or multiple hour deco obligations you can only listen to the continuous alarm and watch as the dome fills with water. Sending the camera with a SMB to surface has its own risks, multiple risks.


In Topic: Just getting started...how am I doing?

01 March 2017 - 01:48 AM

Your Aquatica housing for the Nikon D7000 camera has a depth rating of 90m/300ft and it can be upgraded to 130m/425 ft. Finding exact reliable depth ratings for each of the dome ports is a bit more difficult. According to Aquatica, they test all their dome ports, macro ports and extensions inhouse to a depth equivalent of 90m/300ft. However, I have seen third party web quotes of using Aquatica housings even upto 700 feet. I personally have been shooting with the 8" acrylic dome at 80m/260ft depths and some of my friends have been shooting with Aquatica housings and domes beyond 100m/330 ft depths. However, you will need the stiffer spring update for deep shots. And I would hesitate taking a 9.25 glass megadome to these depths...
 
For comparison, the Nauticam optical glass dome ports are rated to either 40m/130ft or 60m/200ft. Other Nauticam acrylic ports are rated from 45m/150ft to 100m/330ft including some special versions. And there has been a test dive to 500ft with the 4.33" dome.
 
The Sea&Sea YS-D2 has a depth rating of 100m/330ft.
 
For deep diving I would pay attention to clean setup of the equipment, e.g. no dangling cords etc. Make sure you can fold the arms and clip the camera away. I definitely would take the neoprene dome cover with me. For gas changes you can temporarily donate the camera to your buddy unless you have video light cords running to batteries on your belt. However, if the need arises, you have to be capable of ascending solo and managing gas switches on your own. That's why clipping the camera away would be a good choice.
 
I also would prepare the camera whilst descending, e.g. perform WB adjustments and prefocusing a bit shallower but in darkness. If you plan to shoot wide angle video shots of wrecks in darkness, you will need a lot of video light. I have been using 2x80W LED video lights on camera arms and/or larger lights off camera. E.g. the video below was shot with only two 300W lights off camera. Getting your light assistants to illuminate the wreck suitably is another story...