I find myself when tying a fly …always wanting to add flash…I also find myself wanting to fish flies with flash…talking trout here…
I know natural insects may be drab but it seems we can always say the flash …attracts…or suggests a gas bubble which is frequent in various stages of insect life.
How do you all feel about flash…I just find myself not having confidence in a fly without flash…but let’s not get into the fish with what you have confidence in thing.
ducksterman -
I tend to not use flash, mostly because I believe that less is more and I am always trying to simplify.
For example, the best midge pattern I have is hook and thread only. The best streamer I have is hook, pine squirrel zonker and thread only. The best big nymph is hook, chenile, rubber legs and thread only. The best small nymph is hook, p.t. fibers, herl, and thread. The best hopper is hook, a foam strip, rubber legs and thread. Kind of a pattern here ??
My copper john eliminates the wing case and epoxy, and I generally stay away from patterns that incorporate more than a few materials or require more than a few steps.
If I included flash or used more materials or tied more complicated patterns, I might catch more fish. But I don’t think fishing would be any more enjoyable than it is now. For example, the moose, and the beaver, and the muskrats, and the eagles, and osprey, and deer, and, well, you get the idea, never take note of flash, and it doesn’t change the cloud formations, or the rock formations along mountain streams, or the color of the foliage, or streambed rocks, and so forth.
If fishing ever gets down to catching for me, I’ll add flash to all the fly tying materials and fly fishing gear I have when I list them for sale. Maybe it will attract some fisherman ( buyers ) ??
John
It is a quandry that I am in also. I usually like to tie 1/2 of the pattern with flash and 1/2 natural. I will tie 6 pheasant tail nymphs with natural colors and 6 with a flashback. When I get to the stream/lake I always select the naturals and seldom the flashbacks. At home I think the flashbacks will catch more fish but on the water I have more confidence in the naturals. Dumb huh? 
Its all together different for bluegills and crappie though , I need some flash for those. Although a no flashy Lady Mc connel worked best for me if I had had one with flash thats the one I’d have used.
ducksterman,
I only used 2 fibers of Krystal Flash in the tail of woolybuggers. The fibers reflect light very well, so 2 fibers was all I needed.
I also tied nymphs with dubbing & flash mixed together.
Doug
A couple of years back I started tying with chenille that had flash installed in the chenille. I really think it it helps attract the fish. I have used it on wild brookies, hatchery bows and all types of pan fish with good results. The stuff I use is called “New Age Chenille” and is made by a company called Riverborn however there are quite a few folks that make a sparkle type chenille.
Tim
Ducksterman,
I like using some flash, like on Pheasant Tail and Hares Ear Nymphs, I really like a flashback style. Others, like the Lightning Bug is almost all flash if you include the natural flash of peacock along with the Mylar. A few strands of flash in the tails of Woolly Buggers are a big help. On really bright days I will tend to use flies with little or no flash, but on cloudy days I tend to use flies with more flash.
Other flies that I tie I use no flash, using only natural materials. It is a personal choice, one that you will be making as well. As suggested, tie up some with flash and some without flash, there will be times that both will be the best fly to use.
Larry 
—sagefisher—
Natural prey that is eaten by fish are in general more flashy than drab and those that are drab tend to have movement. If the prey is drab and has no movement, then it doesn’t get eaten because the fish can’t detect it or separate it from the herd.
IMO, the flash off the hook, especially from successful flys where the enamel has worn off, is enough to differentiate your immitation from the naturals and will attract the fish to your fly. There are some patterns, like thread midges, where its all about the hook flash. But sometimes that is not enough and replacing the thread body with krystal flash is better.
I use patterns that are as complex as needed to catch fish, which is generally far less than most standard patterns, but I don’t have any arbitrary limit to the number of materials or time. The fish tell me how complex my flys need to be. Generally speaking, that means adding some flash 
… and for me, when fishing becomes not about catching fish, then I’ll leave the rod home and go hiking or boating.
I watched Denny Rickards tie at a show this winter. He was tying up a lake streamer. As he was tying, he said something like, “if you’re gonna add flash, this is where you’d do it.” He then went on to make the point that flash is never necessary, but it probably never hurts either. His opinion was that flash is for the fisherman, not the fish.
I’m of the opinion of, “if you think it helps, then it does.”
I tie all my caddis with a hot butt. Read about it one time, tried it and had success. Was it because of the hot butt? Probably not. The hot butt probably has nothing to do with anything, but I’ve had tons of success with that tie, so why go back?
I’ve been independently studying this subject for many years, my conclusion is that the variables ( Just a few of which would be water clarity, light conditions, species sought, forage base. ) are to broad to apply a good / bad, yes / no answer.
If anyones interested, I’d suggest as a starter course, setting up an aquarium with the ability to control the amount and direction of light ( the sun rises and sets ). You may wish to incorporate a water jet to simulate current or retrieval.
One might be surprised at the appearance of some flash fibers absent direct light, or exposing them to low light and bright light. If you fish under a variety of water clarity conditions then simply running clear water tests won’t be enough. Be willing to suspend small amounts of earth into the water, to change the clarity of the water and then retest. Obviously if you have water staining issues, for instance, red clay banks where you fish your flashy flies, then suspending a small amount of that earth into the aquariums water would render a more accurate conclusion.
Not only the amount of flash, but where the flash is applied to the fly, ( lateral’s, dorsal, ribbing, collars, tailings, etc.) in concert with the flies attitude in the water column ( hanging vertically, stripped along horizontally, etc. ) will render widely ranging results.
…and let’s not forget the fish we’re tying these gems for, just exactly what can they see and what influences their feeding choices.
If you’re really interested in the subject and would like to do more research, look outside of the fly fishing community as well. There is much to be learned from other fishing disciplines.
Is he nuts? Certifiable, at one point I rigged a home made underwater microphone up to a video camera so I could record the sights & sounds of ( flies ) and a crayfish as it moved over the rocky and pebbled aquarium bottom.
Which brings up a topic for another day " Rattle chambers for flies ". Forget what they sound like when you shake them next to your ear. Do they really work when incorporated into a fly then submerged and stripped, or placed into a direct current or bounced along the bottom?
The more I investigate, the more questions I have.
All for now, Dave
P.S.
Having done and said all of that, do I incorporated flash into my flies?
Yes, in many and to varying degrees, right down to none at all in certain patterns.
Do the fish " always " agree with my decisions?
They’re fish !
They haven’t taken the time to do all of this research, so at times their ignorance of my conclusions is quite evident.
Let’s not discount one other strong possibility, operator error.
This is a multidimensional game. One of those dimensions being proper presentation, so having the perfect fly isn’t always enough.
It’s akin to those who say graphs or fish finders don’t work. To me a graph is a tool that gives an accurate depiction of an anglers ability to catch fish. If they mark fish but catch nothing, then the graph must be faulty…
B^)
Been fun, gotta’ run…
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