Monday 3 August 2015

Video Light for stills

I tried using one of my video lights as a light for my stills camera. I mounted it like so:



The articulated arm used to have a strobe on it but it flooded hence the need for some light!
Here are some examples of the picture, mostly in the 20-30m range, vis was pretty good at 5-10m, across multiple dives.


Crab was out in the open so no rocks to obscure the light. No particulates in the water either or very little, treated it like a strobe where you want as little of the beam in front of the lense.



White balance incorrectly set for the video light, suspect I had used it topside and not corrected to use the video light. I've dedicated a button on the Canon s95 to reset white balance, just do it before taking a series of shots.


Positioning of video light on arm all important.


Love these little fellas... nice and in focus with the light. These are old ropes on an LST tank landing ship.


Again, I think I was shooting ambient light, the vis was that good at 25m! But switching to using the video light you get the colour temperature differences..


Capstan on the Susan B. Anthony troop ship, stern. This was taken about 1m away and you can just see the light affecting the colour of the fried egg anemones. 


Starfish


Cone of light visible but its in-focus and adds context..



Tuesday 19 May 2015

New double video light rig





Trying something new for a video light right. When the lights are bolted onto the side of the Goodman handle I find the backscatter to be quite noticable, so this new rig is to push the lights further away from the camera and at an angle to reduce it... Its experimental at this stage... but here goes...

Ingredients:

Loc-Line Coolant Hose Pack
Description
Standard Pack of Coolant Hose containing 2 x 5.3/4" of 1/4" hose (10 Segments),
3 Nozzles (1/16, 1/8 & 1/4")
 and
1/8" &1/4" Male NPT Connectors.
£12.76



EPDM Rubber Lined P Clips Air Hose Pipe Clamps Cable Retention Tube Clip Mikalor
( 251259923794 )
Material: W1 Mild Steel Zinc Plated DIN 3016 (PHC-**)
Sold Per: 5 (Five) Clips Pack
Size: 26mm Pipe Retaining Clamp
£3.85        for the 4000lm torch




M4 SOCKET ALLEN CAP HEAD HEX KEY SCREW BOLT A2 STAINLESS STEEL (ABOLT-FTB)
£1.35 for 10

M3 M4 M5 M6 M8 M10 M12 A4 MARINE STAINLESS NYLOC NYLON INSERT HEXAGON LOCK NUTS
( 111035553279 )
£1.20

100g Polymorph Thermoplastic

To fix the loc-line to the Goodman handle I've cut the threaded section off the loc-line base. Its quite thin so a junior hacksaw will do it easily.



Then bolted the base to the handle with the bolts threaded through the base.



Once both loc-line bases are bolted securely to the handle I made the connectors for the torches. For these I used the nozzle ends provided in the pack, choosing the two largest ones. The finished product looks like this:


To make the hole for the bolt I used a soldering iron, it could be drilled but its quite a hard polished plastic so melting a hole was a lot easier.



Passing the bolt through...


I later added a washer either side but its not shown in these photos..

To make the hose clip connection more rigid, I used a small of piece of polymorph plastic to stabalise it. Take a small piece, say a lump the size a coin, melt it in boiling water and then place it between the hose clip and the nozzle end when you tighten the bolt up. It will form into the correct shape and solidify.



You can use the soldering iron to melt the polymorph plastic around the edges to make it neater.

To plug the whole thing together, lay the loc-line pieces in boiling hot water for a few minutes and then apply a little pressure.

The torches I've used in this example are the two LED torches I've previously reviewed on my blog, one with reflector removed for video and just a normal 4000lm torch with reflector.

I've added a chord to tie the torches to the handle, just in case the loc-line is not strong enough. Its 1/4" loc-line, out of water is seems a little flimsy but I'm hoping in water it will be ok. Its the same as the Ikelite kit.

I over tightened one of the nozzle heads and cracked it, so i'm going to reinforce them with some liquid metal or resin.. not done that yet.

First outing this week...

OK, the arms work really well, the connections stayed tight and secure for 6 dives. In the water they support the weight of the torches fine. Out of water they move a little.

The non-modified torch with its reflectors still in, was no good for video, hot spot ruined the video.

The video camera also developed a nasty fault of not turning on... so not to successful!

My 3mm gloves got ripped by the bolts connecting the arms to the goodman handle, so I think the bolts need to be reduced in length.