Making Your Range Finder Brighter – DIY

I’ve devised a couple ways to make the Range Finder Image on my cameras brighter and have more contrast. Finally I came up with a plan. First of all, you need to know how a basic range finder viewfinder works. I’ve made up a little schematic.

Caution! Before you proceed, make sure you do NOT touch any of the mirrors or beam splitters in the range finder compartment or your focus will be altered. Proceed with extreme caution.

It should be pretty self explanatory. To make the range finder image brighter, you need to maximize the light that is gathering onto the RF mirror and the Frame Line Mirror. First and most obvious, you need to make sure everything’s clean. Secondly, if your camera came with a colorized RF and FL window, such as the green one installed on Petri cameras, replace it with a clear one. It’s not that hard to cut plexi-glass. However, the color of the projected image on the Beam Splitter will be altered.

Alright, now we took care of that part, what if it’s still not bright enough for you? There are two more tricks.

“Make your View finder darker so your Range Finder appears brighter!”

First and the easiest, cut up a piece of electrical tape to the size of a small dot, and place it in front of your view finder glass. That will cover up the light coming into the VF on your projected RF image and make it appear to be brighter. However this method has it flaws. What if you are focusing on something that is smaller than the RF projected image (the dot), for example, someone’s eye. That’s not going to work too well.

So, I came up with a second plan. I would like you to take a pair of lightly tinted sun glasses and put them in front of the view finder. You should find that, all of a sudden, your view finder is significantly darker but your frame lines and the RF image are a LOT brighter and more contrasty for you to focus. You will need to find suitable material with the correct tint you desire to make this work. Myself, i cut up a pair of 3D movie glasses, they work pretty good. You can either tape it in front of the VF window so you can take it off anytime, or like myself, take the top cover off and glue it directly in front of the VF glass.

Here are some samples of what your View Finder will look like.

Indoor in dim lighting. (Petri 1.9 CSS)

Same viewfinder in day time.

I’ve made such modifications to both my Petri 1.9 and my Olympus 35 RC.
I present to you, my Petri 1.9 Color Corrected Super, CUSTOM.
(if anything i think it looks better with a clear RF window)