Otter wrote:Since this was touched on recently and something that is within our grasp and probably goes to the very core of many flymphs.
From a practical viewpoint how does one go about determining the translucent colour and thus matching it on our patterns.
Obviously we can look at a backlit natural or fully lit natural , is it necessary to do so under various light conditions.. and compare the artifical under similar conditions. Obviously our artifical needs to be submerged and similarily lit.
Any pitfalls here than one should be aware of. And any opinions on how accurate the translucent colour needs to be,
I hope many of u flymphers can join in this conversation.
If you look at the natural fairly brightly backlit but under such conditions that the total ambient light does not prevent you from seeing the translucence, ( under very bright backlight you will only see a silhouette, and if too much light falls directly on the fly then you will only see the reflected light), then you have a good guide to the translucence colour you want in the artificial. Usually this will then work well under any conditions where it will work at all, because it then automatically emulates the natural under those conditions. What you then have is basically a "broad spectrum" fly.
Flymphs, and palmered patterns like "Stewart" or "Baillie" style semi-palmered "spiders" are probably the best "general" wet flies extant, and are also often very good indeed as "match-hatchers" when appropriately dressed and fished.
I think there are a number of reasons for this. First of all, contrary to popular opinion ( What a surprise!
), I don't think trout can see very well at all, or interpret what they see very accurately. This is why fly-fishing as such works as well as it does. If trout could see well and interpret what they see correctly then nobody would catch any as they would immediately detect the fraud. Even the best flies are only poor imitations of naturals, basically caricatures, and "exact-imitation" simply does not work very well in the majority of cases even when achievable as a workable fly.
The diffuse, but still similar to the natural, outline of many of these flies suffices to fool trout. In a lot of cases the subtle movement of such flies also suggests life. There is always at least minimal drag on sub-surface flies in moving water and this causes movement in mobile hackles. ( This is because surface water invariably moves faster than the water beneath it, and the leader or line is on the surface, this causes drag, which causes pressure on the fibres and thus movement), the deeper you fish the flies the more drag occurs, ( This of course applies to floating lines and "conventional" methods of fishing). The hackle and dubbing on such flies also appears translucent, as long as it is properly applied, and this also suggests the translucence of the naturals.
Finding the right translucence colour is merely a matter of looking at a natural in the right conditions from the appropriate angle. Some observations are surprising when one first sees them. The bright orange appearance of a Blue Winged Olive when backlit, although it looks green/olive in direct light, is especially surprising. Obviously this is what the fish see too, as an orange quill is usually quite deadly in a BWO hatch while olive bodied imitations either don't work at all or only poorly.
This "orange theme" is quite common, especially among terrestrials, and is usually caused by the presence of carotene
* in the carapace of the insect. Such insects may appear to be black when viewed from above in normal light, but appear orange or brown toned when backlit. This is especially evident in the cases of some beetles, but is not confined to them. Many other insects appear to be a different colour when viewed from a different angle. I think this also explains why silk works so well for quite a number of flies, It is either translucent, or gives the appearance of being so ( Waxed silk).
The angle of light incidence also affects the translucence, Especially noticeable at dawn and dusk.
So all you really have to do is change your point of view!
' http://en.wikipedia.org/wiki/Carotene
TL
MC