[Matt Henderson]

I'll admit it. I'm a sucker for crystal flash etc for using on salmon flies and lures. However recently more and more UV products are coming onto the market. I got some UV varnish and some UV olive flash the other day. Now I varnished my fluorescent coneheads with it and used some of the flash. When in the water it goes slightly purple. Are these materials any good ie just a way of tricking the gullible like me?

Cheers

Matt

[Barry Robertson]

In my experiences i find the fish either want uv or they dont!
And if they dont they reaaly dont!
I played about with uv flies and non uv flies at a heavily stocked fishery over the winter and found over a couple of outings they wanted the uv flies more!
But....
One day they only wanted a drab black fly with no uv at all in it and nothing else! I caught plenty on a plain black buzzer and then changed to a black uv buzzer and nothing at all 
I also found that materials that said nothing about uv on the packet actually turned up really really bright under the uv torch!
For example try and tie a black buzzer with a colar of fluro yellow utc thread  behind the thorax, this comes up crazy under the uv torch and has no mention of on the spool

[Matt Henderson]

But is there UV light under the water? Maybe I'll have to go for a swim in the Don one day with my fly box! I guess what i'm really asking us does a UV fly look a lot different in the water than a plain one?

[Barry Robertson]

I think it depends on the light and the clarity of the water, but apparently once a fish reaches a certain age/size is looses its ability to see uv 

[Rob Brownfield]

I think UV materials arnt actually reflecting UV light.  I will try to explain.

Those of us old enough to remember the 80's may well remember going into night clubs and seeing girls White underwear glowing bright White/blue under UV lighting in night clubs etc. Same with teeth, White hair and even some drinks. That UV light was in fact Actinic light.
Actinic light is a blue wavelength that certain colours reflect, making them almost glow. I use Actinic light on my reef tank firstly to "feed" my corals but also to make them fluorece and look stunning. If I open my fly boxes in the same room the tank is in, certain colours leap out at me, especially lime green, White, peach, orange etc etc.

As many will know, UV light is extremely harmful. When many of these materials hit the shelves they were demonstrated by using "black light", also known incorrectly as UV. Mostly it was Actinic that was used.

So, when these materials are used underwater, the blue wavelength penetrates the deepest and thus these materials tend to reflect back those wavelengths and appear to glow.

I tried taking some photos of the flies next to my reef tank, but the camera does not pick up the colours.

I hope that makes sense? If anyone is out Banchory/aboyne way and wants to see what there flies look like you are more than welcome to try them under actinic lighting. It's quiet spectacular!