Introduction: HOW TO: Build a Holga M-mount Lens
The premise for making this lens is simple: I want a Holga lens for my Epson D-R1 digital rangefinder. Why hack-off a rangefinder lens and mount it on another rangefinder??? Well, for its trippy optical quality, and to contribute something useful to the very small digital rangefinder community. "Wait, hold-up! So it's only a few clicks away in Photoshop"! Good question, but even with Photoshop there is a slight problem- I don't know Photoshop... There I said it, now I am embarrased. The proper way to do this is shoot with film, scan, and import to PC, or have the lab scan it on to a CD-ROM for you. However, buying, developing, scanning films can get expansive, especially when you're experimenting with a homemade lens. Excuses, excuses... Hey, let's not become bankrupt around tax season over a $32 (tools not included) lens.
Before we start, EOS-Holga mod posted on Litratista.org EOS-Holga mod posted on Litratista.org, and aTanguay's Nikon-Holga mod posted on flickraTanguay's Nikon-Holga mod posted on flickr are two must-reads. I started thinking "Hmm... what if" after reading their posts and came up the idea for my little project! However, they mounted their Holga on DSLR bodies which you can see the focus. On uncoupled rangefinders, you'll have to eyeball the focusing distance and set correct foucsing (or little 'flower' icon for near, 'person' for mid, and 'mountain' for far). All of this will be academic if I can build a lens that will have the correct focal length (60mm) to be in focus at infinite.
Drawing diagrams and reading math textbooks won't help, so I'm just going to build one and see how it goes. After pounding two cans of Red Bull, I am saying "Let's do this"!!!
Step 1: Materials
You'll need the following:
1- ONE Holga & lens cap. Preferably a spare one because you WILL DESTROY it.
2- ONE 'Canplas' brand '1-1/2" ABS-DWV Trap Adaptor' bought from Osh; more info on this later.
3- ONE M-MOUNT BODY CAP bought from eBay.
4- ONE black masking tape. I like the pH neutral kind because it has just the right amount of adhesiveness, not too gummy either.
Step 2: Tools
Tools you'll need:
1- One screw driver for small screws.
2- One sharp scissor.
3- An Xacto or utility knife.
4- One mini hacksaw.
5- One 'Dremel' brand or equal, polishing and sanding drill bits.
6- One 1-1/2" hole saw.
7- One electric drill, don't make the mistake of buying a hugeass drill that weighs a brick...
8- Drill bits of various diameters.
Step 3: Say Buh-Bye to Your Holga
"Buh-Bye"! I don't know what else you can do with a plastic camera with no lens. Use it for parts? Fill it with concrete and use it as a door stop or paper weight?
Anyway, remove the back cover and disassemble the lens unit.
Step 4: Detach the Lens Housing
Here is the inside of the Holga. There is a 6x6 film adaptor, take that out to reveal the two small screws at top and bottom. Remove the two screws.
Step 5: Unscrew the Shutter Mechanism
See those two long tube thingy sticking out? Those are the holes for the two screws you just removed.
Now, unscrew two more screws from the circular whatyoumacallit to completely separate lens housing from body. You can sever the yellow wire if you wish.
Step 6: Removing the Last Screw
Remove the last screw to completely detach the Holga lens barrel from the shutter housing.
Step 7: The New Lens Barrel
This is your new lens barrel, available at Osh or HomeDepot. Its full name is- "Male 1-1/2" spigot x slip-joint trap adaptor with washer and nut", and yes, you have to say it in one breath. See the next photo for an actual store sales tag.
Osh carries the 'Canplas' brand, while HomeDepot carries the Nibco' brand. The only difference is Nibco makes a white screw-on nut.
Step 8: Actual Sales Tag at Osh
Print and show store clerk.
Step 9: The Adaptor (Spigot X Slip-Joint)
- The modified Holga lens will be attached to the top of the screw-on nut (#2).
- Then it will be screwed on to the spigot (#1) for focusing.
- The m-mount body cap will be attached to the bottom of the slip joint (#4).
- Trash #3.
Step 10: Cut Slip-Joint End of Adaptor
With a mini hack saw, cut the slip-join end of the adaptor, leaving just about 1/8" max left. This 1/8" will give you the right focus at infinite.
Smoothen all uneven edges, and trim sharp edge that are sticking out if you're using glue. Me? I am a masking tape kinda guy, so I am not going to bother with sanding.
Step 11: Core-out the M Body Cap
With a 1-1/2" hole saw/drill, remove all the plastic in the center leaving you with just a ring with m-mount teeth on it. 1-1/2" is a near perfect fit, but remember to drill from TOP as the 1-1/2" hole saw won't fit through the bottom. Picture shown here is the cap's bottom.
Step 12: Cut the Holga Barrel
Now, with the mini hacksaw, saw off the Holga lens barrel. Be cautious about the two plastic tabs that act as focus guides/stops. You can remove the two tabs with a heated knife, chisel it off with a flat head screw driver, or saw them off cleanly. Whatever works, just don't cut yourself.
Again, if you're glueing everything together, smoothen the edges to get a better bonding.
Step 13: This Is What It Looks Like
Those two ugly marks are the remains of the focusing tabs. I heated a small pocket knife and it was like melting butter, but I had to endure the nauseous fume, so have proper ventilation, hide the kiddies, and ALWAYS wear goggles for protection.
Step 14: The New Lens Cap
Before putting away your electril drill, drill a 1/4" to 1/2" hole (or any other diameter you desire) on the Holga lens cap. I messed-up the cap by ripping a huge gnarly hole when retrieving the drill bit. The cap is made out of soft plastic, so exercise some caution when drilling. I patched it up nicely with a thin cardboard and a 1/2" hole.
Step 15: The Final Assembly
Put all your tools away, wash your hands, blow off all plastic saw dust, now you can assemble the new lens in this order-
1 goes on top of 2,
2 on top of 3,
3 screws on to 4,
4 on top of 5,
and 5 goes on to your camera.
Step 16: Tape the Lens to the Screw-on Nut
Tape the Holga lens on to the screw-on adaptor nut. And when taking macro pictures of your finger, always apply generous amount of lotion...
Step 17: Attach Lens Cap
Attach lens cap. Remove excess tape so it snugs on.
Step 18: Tape Body Cap to Slip-Joint
Now attach the body cap onto the slip-joint. Apply tape into the 1/8" gap as shown in picture.
Step 19: Apply Pressure
Get something thin into the gap and apply some pressure to flatten the tape.
Step 20: Tah-Dah
Step 21: Instruction on Focusing
After testing the lens, I happy to report it actually works!
With the lens screwed on tight (but not too tight), we can get focus from infinite to about 15'.
With the lens barely hanging on at the last spiral (not falling off), it can get as close as 1.5'.
Experiment with it, and refer to the picture for more info. Lastly, drop me a line here or email to tell me how you like it.
Step 22: Sample Picture #1
You can shoot without the cap.
Step 23: Sample Picture #2
Or, you can shoot with the cap on for the classical Holga 6x6 look.