Fly colours

[Mike Connor]

This is actually fairly common, although it is not always obvious. Using the wrong colour thread on some imitations makes them much less effective at certain times. I am satisfied that this is due to incorrect translucence colour. You will often not be able to see this on the water, as it depends entirely on the viewing angle of the fish and where the light is coming from.

If you use black thread on some flies that use orange as a body ( spinners especially) you wont catch much on them, although they do work sometimes. If the fish see a silhouette then they will work, if the fish see the translucence then they wont.

This is also a problem with some materials that use "solid" body material like peacock "quill". If you want to simulate the orange translucence of a fly then you need to use orange quill, this APPEARS to be orange even in reflected light, so it usually works, although of course it is not translucent at all except in very strong light, although this also depends on the viewing angle. More translucent flies generally work better though and far more consistently.

I have a couple of pictures somewhere which show this very clearly. I will try to dig them out of wherever they are.

TL
MC

[Mike Connor]

This is an extract from John Goddard's Waterside Guide";

http://www.amazon.co.uk/John-Goddards-W ... 0044401795

http://www.anglebooks.com/product.php/2 ... and-lakes-

I have added some comments and pictures etc where appropriate;

QUOTE ( with added comments etc. MC)

A prime example of the importance of colour alone can be established with that old and well known pattern, the Orange Quill. It is generally accepted that one of the most difficult of all the upwinged flies to imitate successfully is the Blue-winged Olive. The body of this dun appears yellow-green ( IN DIRECT LIGHT! MC) and has been likened to a ripening greengage,



yet long ago a fly-fisher discovered by accident that the Orange Quill was very successful when B-WO duns were hatching, and even today is still in favour. That success seems strange when the bright orange body of the artificial is compared with the drab,greenish body of the natural. But the reason has now been established. The true colour of the body is in fact orange, ( Also looks orange when viewed in the right light! Translucence! MC), but it is overlaid with a slaty-blue integument and appears to our eyes as yellow-green. The eye of a trout probably relegates the blue and green into an unseen background, so that to it the body appears as a distinct orange. ( Interesting idea, but I don't think it is correct. The fly appears orange to humans as well when viewed in the right light, this is due to the translucence. MC).

UNQUOTE

TL
MC

[Mike Connor]

You can now see lots of photos of natural flies on the web;

https://www.google.com/search?q=blue+wi ... 62&bih=811

You can also see why most of the artificials don't work very well! They are mostly green or olive! Even the naturals often appear green in the photos. If you take photos with enough back lighting, ( which people rarely do as they want detailed photos with direct lighting) then they appear orange. The effect is entirely depedent on the light conditions and is also perfectly visible to humans if you use the right lighting setup. The camera also shows it as it appears to a human eye in the right light and at the RIGHT ANGLE OF VIEW! The fish usually see these flies backlit, (against the light), so they appear orange to the fish. This is why green/olive coloured artificials either don't work well or not at all.

TL
MC

[Otter]

If you use black thread on some flies that use orange as a body ( spinners especially) you wont catch much on them, although they do work sometimes. If the fish see a silhouette then they will work, if the fish see the translucence then they wont.

TL
MC

Probably a silly question, does translucent colour vary with the light as we move towards silhouette ?.

What I am getting at is , can a pattern exhibit correct or at least sufficently correct translucence colour in one instance of light and degrade as the light changes. In other words , taking on board the silhouette vrs translucence equation which makes obvious sense. if we place the importance of the translucent colour on a scale of importance from 0 to 10 , 0 being where silhouette takes over ( if indeed it does). Within the conditions where translucence is probably of major importance, is it likely that any given pattern may work up to a certain level of translucence but may fail above that - e.g. works well up to a 5 , and degrades as the importance of translucence moves up the scale.

Maybe this is too simplistic and way of the mark , but it would sure as hell would explain the differential between a good and a great fly, where for all the world they seem very very similar .

[Mike Connor]

If you use black thread on some flies that use orange as a body ( spinners especially) you wont catch much on them, although they do work sometimes. If the fish see a silhouette then they will work, if the fish see the translucence then they wont.

TL
MC

Probably a silly question, does translucent colour vary with the light as we move towards silhouette ?.

What I am getting at is , can a pattern exhibit correct or at least sufficently correct translucence colour in one instance of light and degrade as the light changes. In other words , taking on board the silhouette vrs translucence equation which makes obvious sense. if we place the importance of the translucent colour on a scale of importance from 0 to 10 , 0 being where silhouette takes over ( if indeed it does). Within the conditions where translucence is probably of major importance, is it likely that any given pattern may work up to a certain level of translucence but may fail above that - e.g. works well up to a 5 , and degrades as the importance of translucence moves up the scale.

Maybe this is too simplistic and way of the mark , but it would sure as hell would explain the differential between a good and a great fly, where for all the world they seem very very similar .

Yes, that is why ( in my opinion) some materials work so much better and more consistently than others, they mimic the behaviour well in varying light conditions. Most materials don't do this and are only effective under very specific conditions. If the light changes they no longer work well or not at all.

Most people look at the colour of a fly in direct light, and choose a material accordingly. This is generally bad because that is not how fish usually see them, they see them from below which means that they are backlit. This effect is very obvious even in extremely low light conditions. It is very accentuated in some conditions and less obvious in others.

I think this is nearly always of major importance. The only time a silhouette pattern works really well is at night, and then a black one works best because there is no colour visible beyond a certain degree of twilight ( http://en.wikipedia.org/wiki/Twilight ). Backlit flies are visible in colour longer for the fish because it is seeing them from below against a light background. You can no longer see colour form above when the fish still can from below. It is quite easy to duplicate this for yourself, just use a lamp you can dim and a light background or put the fly on glass and view it from below. Altering the angle and intensity of the light will change the colours you see. In bright light you will often see a silhouette, because the amount of light is too great altogether. If the light on the fly directly is less than the background light you will see the translucence colours. I think this is what the fish see most of the time.

This is also why WIP's ( Wing interference patterns) http://whyevolutionistrue.wordpress.com ... t-of-that/ are only visible against dark backgrounds, it is is a function of the amount and the angle of light. You can see them perfectly well under the right conditions and I am pretty sure the fish can too.

Most people never see them because they don't look at them under the right conditions.

TL
MC

[Mike Connor]

By the way, I think this is also a reason why fish prefer to feed in low light conditions. I think they need to see the colours of many flies, and they can only do so in low light conditions when the flies are backlit.

This is exactly the same for humans and you can duplicate and photograph these effects. It is not based on any abstruse theories.

One may study and consider these things for a long time and come up with quite a few ideas about why some things work and others don't. I believe this is connected to many things in regard to the behaviour of fish. You just have to look at things the way a fish does and under the same conditions.

TL
MC

[Otter]

If your opinion is indeed correct and from where I am sitting it is the most plausible I have come accross, then one must either develop and carry a small range of flies to cover a range of translucence colours and be very quick to change or work hard at identifying as you are doing the material that works accross a range of translucent colour for particular imitations.

Others have probably long understood some of this but its the first time I have come accross an in depth clear reason for looking at precise translucency colour as against a general need for translucence which is probably more well known.

Maybe its down to me not even half fully understanding these things but I am sure that I am not the only one that will benefit from this insight - many thanks, much appreciated.

[Mike Connor]

Further to this, this may explain why some barred feathers on some flies work so well ( Adams, March Brown etc etc). They might not be exactly the right colours for the wips ( or coincidentally they might be), but the patterns are similar. This is doubtless a recognition factor for the fish. Various "broken coloured" materials work a lot better than plain colours on a very large number of flies.

I will know more about this when I get some decent photos of various wing interference patterns from various natural insects.

TL
MC

[Mike Connor]

If your opinion is indeed correct and from where I am sitting it is the most plausible I have come accross, then one must either develop and carry a small range of flies to cover a range of translucence colours and be very quick to change or work hard at identifying as you are doing the material that works accross a range of translucent colour for particular imitations.

Others have probably long understood this but its the first time I have come accross an in depth clear reason for looking at precise translucency colour as against a general need for translucence which is probably more well known.

Maybe its down to me not even half fully understanding these things but I am sure that I am not the only one that will benefit from this insight - many thanks, much appreciated.

Well, I would rather find materials which behave as the natural flies do. I don't want to carry a whole load of specialised patterns. According to my research nobody has done it before and quite a few things were not known or simply ignored before. Some effects were known and exploited, but how or why was not investigated, or at least not in the right way.

For me, the fact that these things are fairly easily checked in general and some results already confirm them is another nail in the coffin for various UV related theories. This will not stop me looking at that too if I can, but I am of the opinion that this is far more relevant and useful.

I should be getting a new special camera some time this week and will no doubt have quite a bit of setting up to do, but I am hoping that will produce interesting and useful results.

TL
MC

[Roadkill]

Now we are in a discussion about translucence and undercolor, the value of which should come as no surprise on the Flymphforum. Here are some relevant words from Pete Hidy's "Open Letter" in 1973 about the flymph:

"...the efficacy of spinning furs and dubbings that are carefully
tapered to achieve lifelike bodies for trout flies. Such
bodies are the key to creating lifelike flymphs that possess
Undercolor, Translucence..."

This value is also known to those who fish the Usual.