As my eyes have aged over the years I have tried several styles of magnifing systems. A magnifayer built into a circular fluorescent lamp, one built ito a head set, and one that came with my ‘daylight lamp’ that clamps to the table.
All three styles are shown here…
http://www.oselectronics.com/ose_p43.htm
All of them worked, all of them have some advantages and disadvantages.
type 1: lens built into lamp
Increased the size of my fly by about 2X, needs to be well adjusted to get fly into focal range. Color of light is a little too blue, so I also needed to suplement with a 60 watt swing arm lamp. Lamp needs to be 8-12 inches from the fly, this can be a little in the way but I quickly got used to it. Good for detail work but I needed to swing it out of the way to see the ‘big picture’ and inspect the complete fly.
type 2: dual lens on head gear
Interchangable lenses let you adjust power to your eye strength, higher powers have shorter focal length and depth of field. You must get used to keeping your head in the correct position to put the fly in the focal range. Hands free operation, nothing to get in the way of tying. Hard to see stuff that is not in the target area or in your periphial feild of view, stuff like tools on the bench or instructions in a book. Some styles flip up out of the way to address this problem.
type 3: lens on adjustable arm clamped to table.
Similar function as the type 1. Frameless lens holder improves field of view, however the area of sharpest focus is in the center (about 2/3 of the diameter) so a 4" diameter lens only has a sharp area of about 2 1/2". I needed to move it around for big flys. The flexible arm adjusts more easily than the swing arm style. Sometimes the arm gets in the way of tying, but it can easily be swung to the side.
What eventually solved the problem was getting better lamp with a higher level of illumination. Now I only use the magnifiers for flies in the size 20-26 range. After years of doubt I finally got an expensive ‘daylight’ brand lamp. The improved illumination eliminated my eye strain and headaches. One feature that I like is that the bulb produces a wide area of illumination instead of a ‘point source’. I get less shadow when my hands are in close since the light comes from a larger surface. I held off for years due to the expense, but this was definiatly worth the price.
This is similar to the lamp I own…
http://www.madisonartshop.com/tatopdamala.html
The daylight company also makes proffesional quality magnifying lamps with natural color bulbs. I havn’t tried them but think they would be excellent, combining a large high grade optical lens with two 13 watt fluorescent bulbs. Someday when I’m feeling rich…
http://us.daylightcompany.com/professional/product/?id=191