( This is a repost into DM.)I was diving in Coz in April. I bought the iTorch Video Pro6 for video and was impressed with the light output and quality of the light. When not using it for video, I used it as a backup light on night dives. It turned out that it's actually too bright and diffuse for night dives. I needed a more piercing beam.
We did a night dive towards the end of the trip and stopped at a small cove just before the exit point at SCC. I switched to the iTorch - the power of the light was astounding. The diffuse nature of the beam LIT up the cove. We saw absolutely everything in there. I decided to use the "UV" option to see if there was any luminescence inside. When I turned it on, I could only see out of my right eye. Left eye was effectively blind. I changed back to white light and left eye turned back on. Back to the UV and same thing again. It was quite scary.
I finished the dive and went back to my room and did the same thing there. Once again, the left eye became inoperative. I knew that the UV option is effectively a purple light at 420nm and should not cause any blindness. At no time did I ever shine the light directly into my eye. I went to the ophthalmologist when I returned who immediately diagnosed me with a rapidly deteriorating cataract. Within three weeks after diagnosis, I was legally blind in that eye! I had the cataract successfully removed yesterday.
I must say that I'm puzzled by the UV blinding effect. Any optical physicists out there that can shed any light (sorry) on this? It did not happen with the red light nor the lower power white lights. (And oh yes, there was no luminescence in the cove).
We did a night dive towards the end of the trip and stopped at a small cove just before the exit point at SCC. I switched to the iTorch - the power of the light was astounding. The diffuse nature of the beam LIT up the cove. We saw absolutely everything in there. I decided to use the "UV" option to see if there was any luminescence inside. When I turned it on, I could only see out of my right eye. Left eye was effectively blind. I changed back to white light and left eye turned back on. Back to the UV and same thing again. It was quite scary.
I finished the dive and went back to my room and did the same thing there. Once again, the left eye became inoperative. I knew that the UV option is effectively a purple light at 420nm and should not cause any blindness. At no time did I ever shine the light directly into my eye. I went to the ophthalmologist when I returned who immediately diagnosed me with a rapidly deteriorating cataract. Within three weeks after diagnosis, I was legally blind in that eye! I had the cataract successfully removed yesterday.
I must say that I'm puzzled by the UV blinding effect. Any optical physicists out there that can shed any light (sorry) on this? It did not happen with the red light nor the lower power white lights. (And oh yes, there was no luminescence in the cove).
