As I work to determine what additional lighting I need for a blackwater dive at Kona, I started reviewing the I-torch line-up. The i-torch video pro3 seems to have a good light output and has red LED as well. They claim 650 lumens from a single Cree MC-E LED. When I visit the Cree website, the highest single MC-E LED they list has 370 lumens in the color range used by i-torch.
Cree MC-E website link
Am I reading the Cree site wrong? Are the i-torch specs 'optimistic'?
From what I have learned about the blackwater dive so far, 500 lumens is the min. I need to add. Any info or comments from others on this site?
You will get better info regarding technical data by using candlepowerforums.com
There is section for diving as well.
I've added some info I think correct, and hope it illuminates more than confuses. I am no expert in this area.
I assume this light will be as focus light? As such, your needs are also based on the autofocus capabilities of the camera. I use a Nikon D2x, and its autofocus capabilities are quite good with lower light levels, as compared to other cameras I've used.
I use a number of different lights, including the Intova Supernova, FIX LED1000DX, and the one I reference below.
Supernova claims 500 lm at 1,000ma, 49 degree beam angle.
Fisheye claims 1,000 lm, and 85 degree angle.
Both draw significantly power than the i-torch.
Because of beam angle differences the output density should be pretty much equivalent.
Both work quite well as spotters, and the Fisheye is "infinitely" variable. However, I lean towards the Supernova as better value, and have two.
I have also worked with smaller spotter lights, akin to the Inon LE240, with narrow beam angles. I find them unsatisfactory. Not bright enough, and too much time spent trying to get the beam on the target. With the lights above, there is rarely a need to do so.
The Cree specs are based on being driven at 350ma. I've seen another dive light using MC-E, claiming 640 lumen at 1500ma.
Theoretical value for 1500ma is somewhere around 1,000 lumen, so a claim of 640 could be reasonable.
http://www.dealextreme.com/p/diving-cree-m...a-4-16340-26498
By the way, this light is great to finding small subject material, but is lousy as a focus light. I mount one like this on my housing as well.
Lumen is difficult to use in comparisons, as it does not take into account density based on beam angle, and without the beam angle it's difficult to draw conclusions, as I note above.
The light you reference has an 80 degree beam angle, runs off 4AAs, and as such, my gut feel is that both output and burn time are exaggerated. I think the wider beam angle works against you as well.
The I-torch may be fine, but I am somewhat leery. I would lean toward something more high powered.
