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Mamiya 4x5/6x12 Ultrawide
For a little less money.
by Bob Hutchinson

I've been looking at the Ultra Wide 6x12 or 6x17 cameras since I built my Mamiya "flat top" to use the 50mm, 65mm and 75mm Mamiya lenses. My attention seems to always become removed from the camera and focused on the staggering prices. I decided that a much less expensive way must be found. After studying the situation and making notes. I decided to just move right into the project. My objective was a small 4x5 box camera with no movements but the ability to mount a variety of lenses, Mamiya Press lenses and 4x5 back accessories.

See test results below.

Angle of View - Width of 6 x 12 Format
With Mamiya Lenses

Format

50mm f6.3 65mm f6.3 75mm f5.6 90/100mm f3.5
6x7 78o 55o 49o 41o
6x9 88o 64o 57o 49o
6x12 98o 81o 73o 64o

When the format gets wide the angle of view figure gets big too. The 6x12 format is 2.25" x 4.5" yielding six exposures on a 120 roll..

Requirements:
  • Low cost.
  • Light weight
  • 4x5 Graflok back that can utilize 6x9 and 6x12 roll holders plus any 4x5 back accessories.
  • Mamiya Press lens mount.


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I already had most of the the Mamiya lenses including the 50mm f6.3, 65mm f6.3, 75mm f5.6, 90mm f3.5 and 100mm f3.5. Armed with the knowledge that a couple of these lenses would cover the 4x5 format with no movements, as in a view camera, I designed in my mind a thin box to replace the front end and bellows of a Graphic View camera with instead a Mamiya Press lens mount. I acquired a Graphic View rear frame and Graflok back with a bad bellows and a Mamiya Standard 23 parts body.

I thought of making the box from several materials including hardwood, aluminum, and ABS plastic. After all, its just a box of the required dimensions to screw to the Graphic frame in place of the bellows.  Of course it will have a front plate or cover to mount the Mamiya lens mounting hardware the proper distance from the film plane. Naturally, the box will have to be a real box, absolutely a rectangular box. A square box. A very, very square box so the lens flange will absolutely parallel to and the proper number of thousandths of inches from the film plane with the lens axis perpendicular to the center of the film format because this is NOT a view camera. It is a camera where these critical dimensions are really critical and will require a great amount of precision in cutting and fitting all of the necessary parts to make a GREAT camera.

This may not be as easy as making a box. I'll need a Bridgeport milling machine to make this camera. (no milling machine is needed.) Can I make a box with tolerances of a few thousandths of and inch with a miter saw? Well . . . .

I did build a great ultra wide photographic tool. Here's how.


Mamiya 4x5/6x12 Ultrawide 
The reason View cameras have backs than can be rotated or removed and reinstalled 90 degrees for verticals is because you can't do the same with the camera. With this hybrid 6x12 camera you reset the camera for verticals because the viewfinder is mounted on top. It has two tripod mounting plates for Bogen tripod heads (you may have a different brand) and can be instantly reset for vertical shots. 

101.jpg (37706 bytes) 107.jpg (30862 bytes)  
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Disassembly
Disassembled the Graphic frame completely and put all parts in a glass dish for safe keeping. Remove the steel attachment frame from the rear end of the bellows and clean it for use as a template later. Place masking tape adjacent to the two threaded studs in the frame. Cut the studs off close to the frame. 

Tripod Plates
Place frame in the vice bottom side up. Place a tripod plate in center slightly to the front so it will not interfere with installation of the Graflok back, clamp and mark in six places, keeping in mind where the holes will sink to. The rear two holes need to be about 5/32" from the edge of the frame to clear light seal area and sink into thicker part of frame. If possible stack with the left side tripod plate and drill both with #31 clearance drill for #4-40 thread and countersink for head clearance.

Reposition each plate and use the #31 drill to just barely dimple the frame as a mark for the tap drill.  Drill and tap each hole and install appropriate length machine screw for trial. These two tripod plates will provide flexible horizontal and vertical mounting. Remove both tripod mounts for later re-attachment.


Grind or file the six little mounting studs or tips off the Graflok back. I guess you're ready to make the box, huh?

The Box
Get your big pad and pencil. The critical dimension is from the lens flange to the front face of the film holder or roll film holder (same as rear holder surface of Graflok back). The figure I use for Mamiya Press stuff is 2.224". Apply this figure to the pad in big characters. Draw a graphical representation that you will understand from the top of the pad to the bottom of the parts that make up the sandwich that makes up the box.

  • Distance from Graflok back to inside front mounting surface of frame.
  • Distance to front of rear light seal (black art paper, about .008").
  • Distance to front of box.
  • Distance to front of front light seal (black art paper).
  • Distance to front of box cover
  • Distance to front of lens hardware light seal.
  • Distance to front of lens flange

I write a description for each object in the stack and its corresponding thickness dimension. I then add up the figures. The greatest flexibility is around the lens hardware. Instead of paper you can use the light seal foam with adhesive. It is twice as thick as the black paper when compressed, about .015"

Cut the Plastic
In your dimension you will have a length for the sides of the box, about 1.353. If you can get smooth ABS 3/8" thick use it, otherwise use PVC. I used the gray stuff. All of it is really messy to cut as the static electricity won't let the chips get away. Keep the shop vacuum handy. You must make precision cuts, square cuts. You may have to clear chips before each cut. Be careful about handling the saw. Don't pull the blade arm to the side on the way down, pull it straight down, no side pressure. Completely clear all chips before each cut.  With the dial caliper make sure each end of each piece is within about .004" of the target length. Make sure you have at least eight good pieces before you get ready to cut the top cover for the box (front plate).

Ok, now that you have made some scrap be sure you have a good stop on the right hand side of the saw. Use a clamp and clear the chips after each cut. Making precise square cuts is not a casual thing with a miter saw. Keep eliminating the variables and you will make it happen. Good thing you bought enough material. After you have used up the first 48" piece of plastic material making scrap you will find that the cutting second piece will yield more success. If the box pieces long sides are not as parallel as you would like don't worry we will fix that a little later. Just get eight pieces close.

After you have eight pieces within the required tolerance reposition the stop to cut two front plates (top of box) 5 15/16" long. Then turn each of the two plates and make a second cut to end up with two 5 15/16" square plates. Don't move the stop. Now cut all of the box sides. Stack a few of the 1.353 box sides against the stop (you are efficient at clearing chips by now) and cut. Don't move the stop. 

Now cut four of the box sides shorter by the thickness of two pieces (should be about .720" shorter. Place two pieces on edge as spacers against the stop and make the cuts. You now have all the pieces to make the one box using the CYA formula- (You may screw up half of the parts.)

Square Em Up
116.jpg (17689 bytes) Using one of the 5 15/16" plates as a flat surface stand a set of two short and two long pieces on edge and clamp with two clamps. The objective is to remove the irregularities from the surfaces and square things up. If you have access to a table belt/disc sander with fine grit belt and stop at one end (I have a $99.00 unit from Home Depot) this will be easy. Settle clamped pieces to the belt and apply light pressure, checking often with the dial caliper to make sure things are square. Don't nick the ends or tip the block of pieces. Don't grind away to much material. When both sides are done the thickness of the sides should be between 1.340" and 1.345". Most important is that the pieces must be square with parallel edges. We can adjust the critical lens flange to back face dimension with light seals during assembly.

This squaring can be done in a vice with a good 10" or 12" mill file and cheap vibrating sander with fine grit paper. Keep the sander flat at all times, don't nick or radius the ends or edges.
 
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Make A Picture Frame (but no 45s)
Get your picture framing fixture and screw it to a 1 x 4 x 6" stick of wood so you can clamp the wood and fixture in the vice. Position a short and long piece, adjust for precise you know what and drill with #43 tap drill using a special important technique - drill no more than 3/8" and pull the drill out and clear chips. Drill about 1/8" (just into the end of the shorter piece) and again pull the drill and clear chips. Do this again and again until you have drilled a minimum of 3/8" in the shorter piece. Reason for this precaution is: Plastic can compact, melt and flow or grow in between the two pieces with enough force to actually slide the shorter piece in the fixture possibly forcing you to scrap the piece.

Before removing the two pieces from the fixture mark the edge of each piece at the joint, A1 and mark the inner side flat of each piece IN. Likewise, you will mark each joint uniquely A2, A3, and A4 or similar for matching later. The IN mark keeps you from countersink the wrong side. Tap the shorter pieces and slightly chamfer after tapping to avoid lips that may prevent mating of this light tight joint.  Clearance drill #31 and carefully countersink the long pieces on the outside and slightly chamfer on the inside.

Assemble the box sides just together but not tight.

Template Handy

Remember the time saving attribute I mentioned about the steel bellows frame? Place the steel frame on one of the 5 15/16"square plates. Figure a way to position and clamp the steel template in the middle of the plate with equal distance around the template edge to the plate edge so you can dimple or mark each hole to be drilled in the plate. I clamped the two to the 109.jpg (30430 bytes) edge of the work bench with three clamps, moving them as need to reach all template holes. I used the automatic center punch (tick). Drill each of the twelve holes clearance drill #31 and countersink the front side.

Fit the box sides to the plate with slight clamping and square the sides with the plate tightening the joint screws slightly as you do. When all is really square clamp some part of the assembly in the vice and using the #31 drill just dimple the edge of the box sides in each of the twelve holes. Remove the plate.

Drill and tap the twelve holes #4-40 and reassemble square and just snug but not tight (Its easy to strip the plastic). Grab the template again and duplicate the procedure from above to mark, drill and tap the back side of your box to mate to the rear frame. That steel template is handy, huh? Well . . .  let's use it now, in conjunction with a sharp box knife or Exacto knife to cut three black art paper light seals and punch or drill the seals for easy screw entry. 

Thinking about getting it all together now? Remove the front plate and find and mark the exact center of the front of the plate. In the drill press use the hole cutting tool to cut a 4 1/8" hole for the Mamiya Standard 23 lens mounting plate (or proper size for the lens mounting hardware). Place the lens mount in hole and mark the area to be filed out for the lens lock mechanism. When ready use the learned technique for positioning the mount on the front plate with equal space around all four sides, clamp and mark for drilling and tapping.

Big Hole
111.jpg (27305 bytes)A friends dad was Trainmaster for a major railroad outfit before he retired. He said the term "big hole" was railroad slang or jargon for emergency stop - locking the brakes on every wheel on the train. In his stories he would relate- "and I had to put-her in big hole." Anyway - I thought about him as I was using the circle cutter to cut the big hole in the front plate. 

Remove the front plate, find and mark the exact center of the front of the 112.jpg (32493 bytes) plate. In the drill press use the hole cutting tool to cut a 4 1/8" hole for the Mamiya Standard 23 lens mounting plate (or proper size for the lens mounting hardware). Place the lens mount in hole and mark the area to be filed out for the lens latching mechanism. When ready, use the learned technique for positioning the mount on the front plate with equal space around all four sides, clamp and mark for drilling and tapping.  (see pictures). I suggest some extra foam and black paper around and over the lens latch as light seal. Check for light leaks.  

Caution about circle cutting. Circle cutting is not hole sawing. A circle cutter usually has a single blade on an adjustable arm. Plastic cuts easy but be patient, especially close to finishing the cut. Be sure something soft is under the plate, like a piece of wood or plastic

The 50mm, 75mm and later 100mm lens do not use the latch but you can cut the latch notch in the lens mounting flange with a Dremel tool with a 1/8" or 3/32" rock.  My 75mm fits tight enough to omit the latch notch but I cut the notch in the 75mm and the 50mm. If the Mamiya Universal lens mount hardware is used the latch problem does not come up.

Clearance drill the lens mount holes for #4-40. Oh No! The #4-40 FHMS screws are too big for the countersunk holes in the lens mount. No, don't countersink the holes. Chuck up each screw in the drill press leaving about 5/16" sticking below the chuck. dress the side of the head with the mill file to a diameter of about .168" to fit nicely in the holes. This camera will be ready for pictures soon. Reassemble the front plate to the box sides with a light seal between, square everything up and just snug the screws.

Stack Up The Parts
Turn the aluminum frame on its back and place one light seal inside, place the box on the seal. You haven't yet prepared the frame for screws yet but we are just measuring the critical distance now. Put the Graflok back to the frame and set the assembly on a flat across the back face. Use the depth measuring feature of the dial caliper to measure the distance from the front plate to the flat. Look at your pad and see what this distance should be. It would be 2.224" less the flange to front plate distance - About 2.149". With the addition of the foam seal between the front plate and lens mount, about .015" compressed, and the thickness of the mounting ring in the lens mount, .060", the distance should be 2.224" when bolted together. Measure carefully while pressuring the stack.

If too great you can use black paper under the lens mount instead of foam and save .008". If too little you can add a second light seal between box and rear frame to add .008".

Check for position and clear depth and drill, countersink and tap four places to hold the Graflok back permanently to the frame. Don't over tighten these screws as warping of the Graflok may occur.  

Prepare the Frame
Clearance drill and countersink the twelve holes in the frame. Re-attach the bubble level mounting flange but without the bubble level using two screws. Clean all areas of the Graflok back and frame that will need flat black paint with acetone or similar degreaser, keeping it away from the two cloth light seal strips. You may even use a brass or similar brush to prepare. Paint the inside of the box (not edges or light seal areas yet) and all other areas that are not supposed to see light except when coming in through the lens. With paint applied no foam seals are necessary between frame and Graflok back but for piece of mind - put em in. Get a sheet of the less dense european 2mm material with adhesive from Fargo Micro-Tools. You may have to ask for the less dense sheets as they don't appear to be on their web.

Let's Point This Baby
117.jpg (29321 bytes) Cut, dress and mark a 1 1/2" length of 1/8" x 1" aluminum to mount an accessory shoe using 3 #2-56 flat head screws (one additional screw totaling three plus a stop screw). Place a pencil mark down the center of the top of the bar. If there was a stop screw available with the shoe measure the diameter and drill a hole for it about .005" smaller as you may not have a tap for it. You may need a small countersink for this job. With your recent experience fabricating things square and perpendicular you already know how important it is to be able to point this baby in the right direction. 

Mount the shoe about 1/16" from the back end of the little aluminum bar. Position and clamp the bar on top of the bubble flange, double check for square with frame, mark and drill and countersink #31 in center of bar close to rear but so the screw will reach through the big hole to the frame (see pictures). Reach vertically to the frame with the drill and dimple the frame for starting the tap drill (#43). Drill and tap this hole in frame #4-40. Mount bar with one screw just snug so you can align bar. Using a precision square align the bar so that the shoe is square, tighten screw, drill two #43 tap holes through and into the bubble flange close to the corners of the bar. Remove the bar, tap the holes and countersink the bar. Remount and tighten screws, check for square. You are now ready point this baby with proper finder.

Bolt It Up
The paper light seal areas need to be made up while the flat black paint is still soft so have everything pre-tested and prepared. Disassemble the box sides and apply flat black paint to the ends of the short pieces, the mating up area on long pieces and reassemble snug but not tight. Apply paint to the top edge of the box and back edge of the front plate. Assemble the box to the front plate with a light seal between, square up, tighten 20 screws. I use the minimum torque setting on my el cheapo drill driver. If in doubt use a hand screwdriver, don't over tighten. Instead of really tight we just use more screws because this is plastic.

Apply paint to the frame light seal area and corresponding light seal area of the box. Assemble with paper seal, screw together, check everything, tighten screws. Check the critical dimension again. Plan adjustment in final body assembly if necessary.

Final Body Assembly
Use foam (.015") or paper (.008") or a combination of the two light seals under lens mount as required for final dimension of 2.225" or close, and tighten 8 screws. You have a camera body. 

Tripod Mounts
Re-attach the two tripod mounts. 

Handle (not a grip)
113.jpg (23571 bytes) Cut a 2 1/4" length of 1/8" x 2" aluminum bar, dress and radius two corners 1/4". In a manner similar to positioning the tripod plates, position the handle mount plate at the bottom of the right side of frame (see pictures). Mark for six #4-40 screws (see pictures), remove, drill for screw clearance (#31), countersink, reposition and just barely dimple the frame with the #31 drill. Remove plate and drill and tap frame #4-40 thread (#43 drill).

Cut a length of oval, oblong, square or smashed round tubing about 1 1/4". A piece of thin wall 1" tubing can be smashed in the smooth vice jaws.  Dress the ends square, position on the handle plate, mark and drill clearance for #10-24 screws as far apart as practical. The tubing I used was oval or oblong chrome plated steel from a closet rod from Home Depot (see picture). Cut back plate for wood handle from 1/8" x 3/4" aluminum bar about 1 1/2" long (see picture) and dress. Position with the larger handle mounting plate and mark or dimple for #10-24 drill and tap for major screws and #6-32 drill and tap for handle screws above and below the tubing position.

Cut the 1" square wood 10 or 12 inches long. Position the handle back plate about 1/16 or an inch from the end of wood mark and drill #6-32 clearance (this should be a tight clearance) and #10-24 for protrusion of major screws into wood about 3/16". Reason for little wood below back plate is so you will be able to grip the big Bogen tripod adjustment lock handle. Handle is offset to the front to clear Polaroid or other bulky film holders on right side of camera.

With a pencil make two marks. One where you want the anti-slip end cap (see pictures) and another one inch further up. Cut on the upper mark at 90 degrees and then the lower mark at 25-35 degrees. Place the handle in the vice with 25 degree cut parallel with the ground and glue the anti slip tip on with Goop or similar adhesive. After it sets for 24 hours finish the handle to suit. 

Three Bubble Spirit Levels
114.jpg (29797 bytes) When using ultra wide format with any focal length the levels are essential for keeping vertical lines parallel. Bubble levels are everywhere. Every kind of small level can be found today. Problem is - none are worth a shit. They aren't even mounted level in their own mounts. Quick test _ note position of bubble, swing around 180 degrees. If position reading is not the same it is bad. I found some shirt pocket levels with pocket clips at at Home Depot mounted in white plastic. I cut them down to just the meat of the level in a white case, dressed the ends and prepared the frame for mounting three by dressing the area with a brass brush and a dab of acetone to degrease the mounting area and the bottom of the level. Hardware store sometimes have aluminum hex shaped shirt pocket levels that can be modified the same way. They only work with the spirit window up.

Mount the camera in the vice level front to back and side to side, really level. Use precision level on the the back of the frame to check front to back, sides for side to side. Remove the Graflok back if necessary as this has got to be right. Loosen the vice slightly, retighten, etc. until all is level. Goop the bottom of the level slightly and press into position (see pictures), making the two little camera levels read exactly the same as the precision level for front to back and side to side readings. Use cue tip soaked with acetone to clean area around the level of excess Goop. Additionally, the front to back level must be perpendicular with the film plane as it will also be used when the camera is in position for vertical shots. Otherwise, a total of four levels would be necessary 

After the glue sets re-position the camera and do the same for the vertical side to side level. The front to back level is used for both horizontal and vertical shots.

Already someone has ask why I don't use the level that came on the camera or the round centering type bubble levels. I don't use them for the very best of reasons: I want a big level of know to me accuracy that I can see with old eyes from a distance. If using a 50, 65, or 75mm lens on a 4 1/2" wide format this level stuff to prevent distortion of vertical lines, especially at the edge of the film, must not be taken lightly.

Test With Lens and Ground Glass
Twist a lens onto the mount, set to largest aperture and attach the ground glass to the Graflok back. Mount on tripod and set up in the garage or shaded area with camera pointed in the direction of a car or something with bright highlights from the sun. If you are 20 years old look at the ground glass for the rest of this test. If old put 4 to 6 diopters on your face. Put the highlights in the middle of the screen and rotate the focus back and forth. As you rotate from close to infinity the highlights should snap into sharp specs just as the focus ring gets to infinity. Focus on an object closer to the camera and measure. If your critical distance is close to 2.224" you are ready to take pictures.

OK, OK, if your really want to test for light leaks do this:  Load a roll film back or, a Polaroid back may be quicker. Take a piece of black electrical tape about 1 3/4" long and fold one end over about 1/2 inch for a tab and stick it to the back of a hand. Advance the roll film to the third exposure, take back to total darkness, in a closet at night if necessary. Pull the dark slide and place the tape on the film and push dark slide back in. Mount holder and take camera out into the sun and pull the dark slide open but not out of the back. Close dark slide, go back to darkness and remove the tape, wind to another exposure, go back into the sun and pull slide all the way out for a few minutes, insert dark slide and wind film all onto the take up spool and process only. The processed film will tell the story about light leaks from the body or the dark slide slot or the back.

Coverage
It appears that all of the Mamiya lenses to 127mm will cover the 6 x 12 format at f16 or smaller. I have not tested for light fall-off at edges.  (Nope. See test info. below.)

    105.jpg (31362 bytes)  106.jpg (44769 bytes)
   Camera with 6x9 back

Cost
The materials are pocket change: 

  • Plastic and wood about $29.00
  • Fasteners - $15.00. 
  • Roll film back of the  6 x 12 variety - $579.00+ used, $769.00+ new at Midwest Photo Exchange
  • 50mm f6.3 - $400.00+ with finder
  • 65mm f6.3 - $200.00+ with finder
  • 75mm f5.6 - $400.00+ with finder
  • 90mm - $65.00 without finder.
  • 100mm -$110.00 without finder
     


Parts Needed

  • Lens mounting hardware from Mamiya Press camera
  • Accessory shoe from Mamiya or other camera
  • Two pieces of sheet PVC, 3/8 inch cut 6 1//4" x 48".
  • 6 #2-56 flat head machine screws, philips head, stainless
  • 12 #4-40 x 1/4" flat head machine screws, philips head, stainless
  • 24 #4-40 x 3/8" flat head machine screws, philips head, stainless
  • 12 #4-40 x 1/2" flat head machine screws, philips head, stainless
  • 12 #4-40 x 5/8" flat head machine screws, philips head, stainless
  • 36 #4-40 x 3/4" flat head machine screws, philips head, stainless
  • 2 #6-32 x 1 1/4" round head machine screws, philips head, stainless
  • 2 #10-24 x 1 3/4" round head machine screws, philips head, stainless
  • 2 #6 flat washers
  • 1 #2-56 plug tap
  • 1 #4-40 plug tap
  • 2 sheets 24" x 30" black art paper about .008" thick
  • 1 bottle of real flat black paint from Fargo Micro-Tools
  • 1 package foam light seal for camera backs - Fargo Micro-Tools
  • 1 stick 1' square hardwood for handle
  • 1 length of 1/8" x 2" aluminum flat bar
  • 1 length of 1/8" x 1" aluminum flat bar
  • 1 length of oval shaped alum. or steel tubing for handle.
  • 2 Bogen rectangular tripod mounting plates - $20.00

Fasteners can be purchased from any well stocked wholesale fastener supply house if you buy a minimum of 100 per size. You can usually buy all of the above #4-40 sizes, 500 total for less than $10.00, about 1/5 of hardware store cost. Hardware stores don't even have them anymore.

Tools Needed & estimated cost.

  • 12 inch power miter saw with fine blade- $275.00
  • Small drill press with a number drill set - $110.00
  • Belt/Disc table sander, 4/6 inch - $99.00
  • 12 inch hacksaw, 24 TPI blade.
  • 10 or 12 inch mill file
  • 6 inch precision machinist square or similar$12.95
  • Small accurate level
  • Drill driver with #1 and #2 Philips bits
  • Some common wood working clamps, c-clamps, etc. non-marring 
  • Bench vice with non marring jaws
  • Common Dial caliper with depth measuring feature - $40.00
  • 5/16" or larger countersink for the flathead screws. Possibly a 3/16" for accessory shoe mounting - $20.00 ea.
  • Adjustable hole drilling tool for up to 4 1/4"" hole in front plate (hardware store - $10.00)
  • Inexpensive picture framing 90 degree clamping fixture (any hardware store - $8.95).

Handy Project Savers

  • General or Stanley automatic center punch (spring loaded adjustable tick for accurately marking for drilling (I would be naked without this wonderful tool).
  • Vibrating electric sander or table belt/disc sander

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I may make another ultra wide for the Graflex XL lens mounting system. The XL 58mm Rodenstock Grandagon and the Planar and Rodenstock 80mm lenses will work fine in a 6x12 camera. 

Also suggested is a smaller 6x12 using the Horseman 6x12 4x5 back as the rear frame element of the camera, a body made from 5/16" or 3/8" PVC or ABS in a manner similar to the camera above and Mamiya lens mounting hardware. This Camera body would be considerably smaller and lighter than the Mamiya 4x5x6x12 Ultrawide but would not have 4x5 flexibility. It would have the 4x5 6x12 6 exposure Horseman back attached to the plastic body with 8 machine screws. Camera cost would be small with the back being the most expensive component at about $775.00 new. Cost for all components except lens and finder would run about $1,000.00, including the Mamiya lens mount components from a run-out Universal, Super or Standard.

The Mamiya 65mm f6.3 lens and finder will run about $200.00. The wonderful 65mm finder would be narrow for the 6x12 format but usable. Everything seen in the finder by moving the eye left and right will be in the picture. Other finder solutions are available but expensive. A 65mm f8.0 Schneider Super Angulon in a Mamiya 65mm focusing mount would be ideal but, again, expensive.

Testing this hybrid
The test roll proved our the proper alignment of the finder and clearly indicated what I suspected - the 75mm covers the 4x5 and 6x12 format just fine. The 50mm and 65mm both have the same circle of coverage, just a little shy of the corners of the 6x12 format. The pictures are of the left 60% or the proofs. Although I have never seen a 127mm lens I believe it will have a circle of coverage similar to the 75mm.

Click Here to contact Bob Hutchinson.

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