A wonderful crystal clear home made loupe

You can make a loupe that rivals the professional model
and do it for less than $10.00

by James (aka GreyWolf) Phillips for largeformatphotography.info

    Well now that I've caught your attention you will want to read on to find out if I am crazy or not. This all started for me when I took a diversion from everyday life and started to read about pinhole cameras one evening. A few days later I was in the local used camera store and asked the owner if he ever got any old lenses that were not of any use to anyone. Well he laughed as he took me down to the basement in a small room and showed me a whole box of mostly 35mm lenses. These lenses were either badly scratched, or had broken pieces. I browsed through the box and selected a Minolta 135 zoom lens with what seemed to be perfect elements but the zoom mechanism was broke. I asked him how much he wanted and he told me I could just have it as I was a good customer. 

    When I got home I took my spanner wrench and began to dissemble the lens. If you have never done this, there is usually a ring at the front that the spanner will fit in and you just unscrew this ring. After that everything is quite easy as most of the parts just fall out. (Terrible thing if you are actually trying to fix it but great if you are just having fun exploring). So here I was with a few lens elements in my hands and wondering if I could use one in a simple box camera. Well to tell the truth the box camera idea petered out as the week went by and I got busier at work. A few weeks later I was viewing negatives on my light box with my Silvestri 10x loupe and suddenly picked up one of the Minolta elements and used it to look at the negative.

  WOW !!! I could not believe how clear a single element made the negative look. So that is how it began. My little wheels started turning as the clutch came out and it was the "pedal to the metal" from here on in. A homemade loupe was born.

    Now all I needed was to find a tube (preferably plastic) to put the doggone thing into. The idea was quite sound but it took me a few weeks to find a suitable tube. The element I was using was about 1.25 inches in diameter (this was the largest element in the lens) and I needed a tube to match. I was in the hardware store and noticed that PVC connectors that are used for electrical conduits seemed about right for the job . I started to measure the fittings and sure enough one of the connectors had a nice lip on the inside that was just right for the element.

 

These are the $6.00 worth of fittings I used.

    The left fitting and the middle fitting go together with the threaded end. This made assembling the loupe an added bonus because I could screw or unscrew the assembly for focusing. (turned out to not be that important). The piece on the right was needed to add a bit of extension to the whole tube so that the focus would be correct. I glued it into the bottom of the middle tube with a bit of PVC Cement I had in the garage. Notice the middle tube has an inside ridge which the lens element sits on.

    By now you are starting to doubt my sanity but just with these three pieces and the element I had a very, very sharp workable loupe that I could compare with my $90.00 Silvestri 10x on the light table. The home made loupe was much brighter, had a much larger viewing circumference and was as equally sharp (both center and edges) as the Silversti.10x. Of course the magnification was only about 5X on the home made loupe.

    My next step was to actually glue the element to the ridge inside the tube using a "Super Glue" type of glue. Here is the only part that I mucked up. I placed a few spots of glue (the Gel type so it did not run down the sides) on the ridge and lowered the element in place. So far it was perfect but I thought I could make one improvement. I decided to place three spots of glue on the top edge to ensure that the element would not pop loose in the cold weather. Sort of make three little "glue tabs" on top. The idea was sound it was just that while I was moving the glue tube from one spot to another it created a very very thin "glue string" that landed across the edge of the element. Next time I'll be more careful.

 

A picture of my spanner wrench and the two elements I salvaged from the Minolta lens.

 

    You can see in the above picture that I obtained two perfect elements from the lens. I saved the one inch element for a future project. I just placed them on those color paint sample cards so that the elements can be seen in a picture. Maybe if I find somebody who has a lathe and can find some PVC 1 1/4 tubing I may get a ledge made and construct a single piece loupe with the one inch element.

 

Here is a picture through the element on the paint sample

 

    The above picture was just to give you an idea on how sharp and clear (right to the edges) these elements are. Take into consideration that the picture is a challenge to take with a cheap digital camera while trying to balance the element. The element is sitting in the tube on the ridge and I have the tube tilted so that light can reflect off the paint sample. I estimate the magnification to be about 4.5x. Just perfect for ground glass focusing.

 

Finished loupe with leather strap and painted.

    The above picture is the completed loupe that I have now tested for focusing on the ground glass. Now I know that the above is definitely not a work of art but BOY! is it ever functional. Being made of PVC pipe it is indestructible and waterproof as well as the bright red paint I had kicking around the garage ensures that nobody in their right mind is going to try to steal it. I then had to add a Canadian touch and taped the leather strap on with good old white hockey tape. Sorry about that Red Green but the duct tape was too big.

    Now that we have had a bit of fun joking about the look and seeing how cheaply and easy it is to build let us do an honest evaluation of the functionality of the product.

1. Robustness         10 out of 10             (you can throw this one at the bears and it won't break)

2. Beauty                  3 out of 10             (Hey! It has leather and uses Hockey tape and is Maple Leaf red)

3. Clarity                10 out of 10             (I and a camera salesman compared it to both a Rodenstock 4X loupe and a Pentax 5.5 X loupe)

                                                                               ( The home made loupe was equal in clarity to the two above)

    I know that there are many of you out there that will not believe that this loupe will rival a Schneider or a Rodenstock but it really does perform as well on the light table as well as the ground glass. The view is crystal clear from edge to edge with no distortion that the human eye can detect. This is not just my opinion but that of a seasoned sales person who sells new loupes. I confess that I was amazed at how good this loupe is for viewing with such a small investment in time and money.

    So what do you do from here if you are interested. Just try to obtain very cheaply an old lens that has at least one good element that you can disassemble and use. After you have the element out you can hold it with your fingers over the light table and confirm what I am saying about the quality of the magnification from edge to edge. Now that you are convinced you can begin to look for a tube of some sort to mount the element into. Just be sure that you get one long enough for your element and one that you can trim to the correct length for focusing. I thought of watching for used toys at the second hand store of perhaps a garage sale to find a tube that might hold the element but just never had the chance. You are going to get quite a surprise to find out how much money you can save and still get a high quality loupe.

View or add new comments
a4x5wolf@yahoo.com