Hi… first post so be gentle (although I have been lurking getting advice for a while!)
I am in the UK and go beach fishing at night quite a bit so have a vast array of headlamps and flashlights.
Recently a friend suggested I use UV tape on the rod tips and buy a UV flashlight to light them up.
It works really well and I am using an Alonefire 003 which runs at 10w (although not really but that’s a different topic! ) at 365nm however I am slightly anxious about how much UV light I should be exposing my eyes to.
Although the flashlight is pointing at the rod tips, I am often dealing with that business end refreshing bait or clearing seaweed from the line.
With a regular light if I was looking at it for periods I would be able to tell because of the glare but with UV I may not realise.
So flashlight experts should I swap back to a conventional LED or am I worrying about nothing!???
I wouldn’t recommend looking into UV light. Your eyes can’t adapt because you can’t see it.
On the other hand there is some research showing that some/many fishes can see UV light. So why don’t you use red light which is absorbed by the water much quicker?
How will it shine in your eyes when baiting the hook, etc? Are you going to tape the light to the rod or something?
While 365nm isn’t really considered that dangerous, you still shouldn’t look right into the flashlight, especially at night when your pupils are dilated. If you’re worried about it shining in someone’s eyes you can wear some normal polycarbonate safety glasses.
I use 380-400nm uv to see floats when i fish at night. foam balls floaters that are sold here are either yellow, or orange, both light up in uv light, some lines also glow in uv, you really do not need uv glasses, unless you plan on looking into it, even if you shine in your eye accidentally for a second, you wont damage your vision, you get a lot more uv in your eyes on a sunny day.
The difference is on a sunny day that UV light from the sun is accompanied by an enormous amount of visible light, so your pupils are pin holes, you squint away, etc. It’s the exact opposite at night so you’d need much less UV to cause damage. I still agree that it’s probably overkill but if I were working with these lights all night I would still pop on some $2 glasses just in case.
The amount of uv a 3w or even 5w led puts out, vs sun light even with pupils shut tight, is still like a grain of sand vs a mountain. that is before you even take exposure time into consideration.
I think it’s a good idea to involve some rough numbers before just assuming, because we can’t see or feel UV brightness like we can with visible light.
I interpret this to mean that when staring directly into the sun (i.e., sample is perpendicular to the sun’s rays), your corneas are absorbing up to 0.076 mW of UV.
If the best UV emitters today are capable of 10% efficiency, a 3W emitter would put up to 0.3 W / square meter onto a surface. If the efficiency is 1, 0.1W / square meter, etc. If we further consider a matte surface reflecting even just 10 of that light energy into your eyes, we’re still at 1-3 mW, nearly twice that of staring into the sun at high noon!
Please feel free to sanity check my interpretation of these numbers, but my takeaway is that using UV blocking glasses would be a wise choice.
Gravelmonkey does bring up a good point, you could always do that.
Looking at objects that fluoresce should not be a problem, so as long as you are not looking into the UV beam you should be fine. That said, what others have mentioned is also true. Your eyes do not properly adjust (constrict/dialate) for the amount of UV light entering them and can be damaged by looking into a UV only beam for too long (the same is true for infrared btw)
Pretty much, you only really exposed to uv when you accidentally point towards your face. the uv is pretty weak, and exposure time is negligible. No point to debate eye damage under these conditions. I build 200w 400nm uv light for target shooting, i point it towards targets, uv reflective balloons filled with uv reflective confetti, it looks awesome when you hit it and it pops, looks like a little fireworks go off.
I was interested so I looked around a little. Here is a good link from the ultraviolet photography forum. There is lots of good info there with references if you want to read up on it. I like the bottom line recommendation from the UVP in house expert: A UVC lamp can injure within seconds, a UVB lamp within seconds to minutes and a UVA lamp in minutes to hours (365nm is UVA). This is for shining the light directly into your eyes. The big problem with UV lights is a direct reflection off of a reflective surface into your eyes, for example water. So watch for that. The best protection is to wear protective glasses. Not great while fishing but the safest thing if you are using the UV light. If you wear glasses anyway, shine your light through the lens at a fluorescent object and see if they filter the UV. Most polycarbonate lenses filter quite a bit.
we use glow-in-the-dark tape.
maybe charge it about every ~20 minutes.
our eyes adapt to the decreasing luminescense.
when the stars are brighter than the tape, recharge.
There is no need for that, there are tiny glowsticks made to go on a tip of the rod, stores that sells fishing gear sell those, iirc, i bought a pack at walmart at one point.
As for tape, i've experimented with different ones, i used to stick them to inside of tir holder, when you shut off the light, it still glows green. the best tape, (brightest, and long lasting), is a sticky gitd exit sign, it is foil based sticker, and the gitd layer is durable, and glows very bright. letters are printed with heavy duty paint, but it comes right off with gel type paint remover. you will not find a better gitd tape. There is also another way, maybe even better overall, clear epoxy mixed with gitd powder, put that on a tip of a fishing rod, and it is there for good. won't come off from hot sun, won't leak glue. The best "charger" for gitd stuff, is uv light, charges fast and bright, even from a distance it does the job pretty good,
I think you forgot one important variable in your calculation, distance from the UV emitting LED. The measurements of daytime UV are taken at sea level on planet earth, not at the surface of the sun (the emitter). You would have to factor in the inverse square of the distance to get the power delivered to your eyes unless you held the led directly up to your cornea. Since we have no idea the distances or how columnated the light coming from he light is, I don’t think it’s possible to calculate this without a few measurements.
