Focus in the Dark

**johnielvis** · 19-Apr-2011, 15:36

i've used a laser with kalart---works better than the original focus light---but you have to find a way to mount it....

NOW HERE'S A TRICK--make a mask in the form of an X for your ground glass---basicaly so the ground glass is covered except for crosshairs exposed---THEN---put your dark cloth around the ground glass--put in a powerful light (depending on how far the throw is)...andturn it on--the light will turn the GG in to a crosshair "slide" at the site of the ground glass (focus point)....and it will project the crosshair on the subject---focus until the crosshairs are sharp on the subject---perfect focus at GG and you don't even need a mannifier since the crosshairs are magnified (projected)...it's just like focusing a projector---just cover the light with the darkcloth so it don't blind you--only the GG gets illuminated....SEE...physics

done it--it works---try it RIGHT NOW....put a pen light against your gg and point it at the wall in the darkened bathroom..focus till the image is sharp and read the distance...amazed????? that's you r new rangefinder!

**rguinter** · 19-Apr-2011, 18:07

Goodness... all these posts about using lasers. Seems I recall another one or two threads here recently on this subject. And I said the same thing there:

I wouldn't even think of going there. Not here in the NYC area with 3 major airports nearby.

Anyone shining a laser around here at night is just begging... and I mean really, really begging for serious trouble.

If you live anywhere near an airport I strongly recommend you put out of your mind any thoughts of using a laser outdoors at night.

Best advice is to find another way to focus.

My 2 cents.

Bob G.

**rjbuzzclick** · 13-Jun-2011, 19:05

Originally Posted by Ivan J. Eberle

The Kalart Synchronized Rangefinders that were mounted to press cameras had an accessory called a Focuspot. This projected a lightbulb two converging filament images on a subject in the dark, when with the synchronizer handles for flashbulbs. Admittedly not too useful in original trim for the distances you describe, but the Focuspots can fairly easily be retrofitted with a red laser-- much brighter than the original.

In use, no need to look through the RF. Just converge the two projected dots into one dot and you're in focus (provided your RF is adjusted spot on). Very quick, very accurate.

My Pacemaker Speed Graphic has this feature (top mounted rangefinder). I've used it a few times and it works really well.

jp · 14-Jun-2011, 07:40

I bought a 5mw green laser, not for my camera, but just to see what the fuss was about and how bright these are. After playing around outdoors with it, it is really bright, too bright for most short-medium range uses. It made snow sparkle, and illuminating reflective surfaces was hard on the eyes. I don't disagree that this would cause serious irritation or blindness aimed into someone's eyes at a short distance for a short time.

Red lasers are easier on the eyes (but still should be used with care) and shoot far enough for most focusing needs. You can even get them that project flat lines or crosshairs like would be used in a laser level. I haven't figured out how I'd mount the laser and battery yet as it's not a high priority for me and I wouldn't want it to look like a mad scientist project.

In an urban environment, I'd be concerned about using a moving red dot laser as lasers are commonly used on pistols for aiming. You might cause someone to think they need to defend themselves because they were illuminated with a red dot.