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Old 28-04-2013, 10:16 PM
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Dimming a Red Dot Finder

Is your red-fot finder or red multi-reticle finder still too bright on the dimmest setting? My multi-reticle finder has 7 brightness settings, but the dimmest setting (1) was still too bright. Now, the simplest of mods has made all the difference.

I had some ND0.6 gel film left over from making a neutral density shield for my laptop. Using two thin, small strips of double sided sticky tape, I stuck a small piece of gel film over the reticle "port".

I noticed no deformation, shift or lack of clarity in the reticle. The reduced brightness is equivalent to 3 steps - that is, the brightness of Setting 1 without the filter is equivalent to Setting 4 with (which is logical, since the film has 25% transmittance). I now have a much more usable range of brightness settings.

Of course, you'll need some suitable neutral density (or perhaps red) film to do the mod.
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Old 29-04-2013, 08:44 PM
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I solved that problem by replacing the resistors (inside the battery compartment) with higher values (this action requires some soldering skills, and of course, SMD resistors of adequate values (10~30x bigger).
This mod also prolongs the battery life (I tend to forget to switch it off after aiming and during exposure...)
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Old 29-04-2013, 10:18 PM
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I thought of something like that, and have made my own LED illuminator for a finderscope in the past, but this mod cost < $1, took 5 minutes and is completely reversible.
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Old 05-05-2013, 01:55 AM
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There was a lot of dew about earlier this evening, and I discovered that the ND film on my dimmed finder dews up quite easily. However, even a simple wipe of a finger across the film removes the dew and nothing seems to distort or shift the projected reticle - even dew simply dims it further.

I was thinking about making a clip-on dew shield for this finder anyway, so now I have more impetus to do so.
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