Video light project based on Sony HVL-80DA

[kamyk]

Hi guys
I'm a absolute beginer. I read what You doing, and it's amazing.
I have two video lights Sony HVL-80DA. My plan is make a powerfull video pack. I was thinking about HID and Led, decide to make a Led version (correct me if I select wrong way). Pictures below shows what i based on.

http://i28.tinypic.com/dondsk.jpg

I want it make as bright as possible with wide beam (video light) and with burn time 100min - two dives . Body is thick plastic so can have problems with heating (I made my homework - check other projects). When empty I have a cylinder 140mm high and 115 mm diameter with 67-70mm glass window(lens?).
Want to use 5*Cree R2 1200-Lumen White Light Drop-in LED Module (52.7mm*42mm/8.4V Max)
Is it possible to find module with 67-70mm diameter, this what found is 52.7mm only. To make it brighter want to use 5XCree SSC-P7, is it make any sense?
This module what i found is 2.6~8.4V so want to use batery pack 4 or 6 Li-Ion 18650 (can't find Li-Ion D-size) like this Li-Ion 18650 Battery: 7.4V 4800mAh (35.5Wh) Rechargeable Battery + 1.2A Smart charger (2.88)

Do I need any driver or Cree Circuit Board ?
I cant wait when I start doing ths lights.

 

[Packhorse]

A plastic cased light is going to have huge issues dissipating the heat from the LED's.
I have not done any real testing but even a 10w LED ( 1 x P7) Maglte build gets hot when used out of the water.
You are talking about a 20-50w build and I just dont think its doing to last.
Also that drop in will produce a tight spot with some spill light. Not idea for a video light. You could use a defuser but then you will lose a lot of light.


A quick google tells me that the light uses a 50w Halogen and gives a 30 min burn time. To match the output ( with nicer colour) you would probably need about 20watt of LED and this will give you over 1 hour of burn time ( using original batteries). You could just say to hell with the thermal issues and do this and you may get away with it if you only used the light for short periods and gave it plenty of time to cool down in between. If you decide to do this then I would strongly suggest a thermal switch in line with the LEDs. This will protect them from over heating. You could always wire in a bypass resistor so when the thermal protection kicks in you still have a bit of light available.





I too have been contemplating a video light set up for some time now.
I have decided on a twin Maglite set up with a single battery cannister.
My LED options are
1.SST-50 with a 44mm aspheric sitting as close to the LED as possible to give the widest beam possible. This may even mean de-domeing the SST so the lens gets a little closer. I have build a SST-90 and aspheric mag and the beam produced nearly fills the frame of my G10 camera ( 28mm lens). I think 2 of these would provide reasonable coverage.

2. Single SST-90/50 or clusters of smaller LEDs with no optics at all.
This option would provide a very wide beam ( 120deg) but a lot of the light would be lost out the sides so perhaps not the most efficient use of light. XR-E's have a 90 deg angle of light dispersement so these may be a better choice. I could simply use multiples of 2 and direct drive them off a 2S Li Ion 7.4v pack. 6 would fit in a mag head quite easily.

 

[kamyk]

Packhorse You make me sad, heh
Like I think, heating is the biggest problem. Single SST-90/50 with or without a 44mm aspheric sounds ok, max 2250/1250 lumens still acceptable. No heating problem with this leds? Thermal switch is a good option, but I don't want to stop filming after 15 min in the middle of interesting frame. What about drivers for them? I have been reading your posts miniMAX with SST-90.

This option would provide a very wide beam ( 120deg)

.
This 120deg underwater should be narrower?

 

[Packhorse]

I am no expert in the who light beam refraction thing.
But if the light beam is refracted and is narrower then what about the view of the camera? wouldnt its view also be effected in the same way?

Regardless of what LED you use if you run lots of power you will generate lots of heat.
Running 2 LEDs at 500ma each will probably produce as much heat as a single LED at 1000ma although the 2 LEDs should produce more light since they are more efficient at lower power levels.

 

[kubi]

Yes, the light is refracted the same way as the camera's view angle will be modified.
So if you dry-test it, it will be the same under water.
A thick lens work a bit like a prism, so it can happen that the edge of the light will be a bit blue or red, but it is not a real issue.

Packhorse is right with the heat too. I would not enclose such a high power LED into a plastic box. The normal light bulb's heat is reflected by the mirror, so it will go to the water. It was OK even with an AR-111 50W halogen. But the LEDs are heating their back and you can not really reflect it out to the water.

I've used an aluminium block for video head machined out from a solid block. D=70mm, d=50mm, h=50mm tube with an 5mm thick full part i the middle to place the LEDs on.
In it I've put 3 MC-E warm white LEDs without any mirror.
The the camera + 0.4x wide converter is wide enough for this setup.

Unfortunately I do not have good pics,only one for the videohead during tests:
http://www.mht.bme.hu/~kubi/canon/lampa/

Actually 2 of this heads made bright daylight in a small cave in Hvar

 

[kamyk]

hmmm
So You suggest that led is not good option with plastic body, but if I'll use hid with metal reflector, a lot of heat will go through lens. Is it acceptable heating solution?

Up to 20 watt LED wins hands down. up to 35 watt its a cl;ose call, 35 watt + HID is the way to go.

So the age old question once again arises. How much light do you need?

For a strictly primary dive light 1200- 1500 lumen works really well for me. ( video/camera needs much more).
This can easily be produced by LED or HID. But for me LED is so much easier to work with and upgrade when better LEDs are available.
__________________
Dive lights by Packhorse

So I need 35/50W HID, is it possible to put everything in my body?

The ballast and bulb can be bought as a automobile headlamp kit.

for example this or similar?

 

[Packhorse]

I doubt you would get the ballast in there as well as the batteries
twin 21w HID's will give you plenty of light. Much more than before but I still dont think you will fit it in.
I hate to say it but I dont think there is any "easy " solution for you.

Honestly I think you would be far better off building a system based on twin Maglite heads and a cannister.
Your options for LEDs is then huge and you could virtually run as many as you can fit. Run time would be as only dictated by the size of the battery cannister.