Vis-A-Dun
The Vis-A-Dun was developed by René Harrop to provide the realistic flush-film profile of a no-hackle Comparadun with the visibility of a parachute fly. Its angled post and comparadun-style wing give the perfect in-film riding position while the bright poly post makes it easy to track on smooth glassy water. Essential during BWO hatches when size 18–22 duns must be matched precisely on spring creeks and tailwaters.
- Type
- dry fly (Mayfly)
- Hook sizes
- #16–22
- Target species
- trout
- Difficulty
- intermediate
- Best seasons
- spring, fall
Materials
- hook: Dry fly hook #16–22
- thread: Olive or gray 10/0
- tail: Dun Microfibbets, split
- body: Olive-gray Superfine dubbing
- wing: Natural deer hair, fanned upright (comparadun style)
- post: White or orange poly yarn, short angled indicator post
Tying steps
- Mount a size 16–22 hook; start thread and tie in a split tail of Microfibbets.
- Dub a slim BWO-colored body to the 3/4 mark.
- Stack a small bunch of deer hair as a comparadun wing; fan it into a half-circle.
- Tie in a short high-vis poly yarn post angled slightly rearward through the wing.
- Build a small neat head ahead of the wing.
- Whip finish and apply a drop of UV resin to the wing base.
- Apply no head cement — the finished fly should have a minimal thread head with no tacky finish near the deer hair wing.
- Inspect the deer hair wing angle from the side — it should lie at about 30 degrees, mimicking a crippled or spent dun.
- Inspect the deer hair wing from the front — it should be a single flat, untwisted fan creating the characteristic comparadun silhouette, not a rounded clump.