Necessity is the mother of Invention. I just got into LF and needed an enlarger for my new 5x7 format! Shows that the ignorant are brave, and sometimes lucky! I toyed with a horizontal design but couldn't figure out how to hold my paper up straight. Thought of pulleys and columns but they were too much work and prone to vibration, then went to the hardware store and found myself in the adjustable shelving section...
Thanks again, you all have made my week!
How did you solve the parallelism problem bewen the table and the head?
Rafael, Ansel Adams had a horizontal enlarger build from an old camera that he built and to hold the paper he used a sheet of steel and used magnets to hold the paper in place. Keep us posted on upgrades and results. What is your 5x7? I have a Kodak 2D and a Seneca 5x7 and two 8x10, Kodak and Seneca. I am building a new 5x7 and just got my rack and pinions yesterday. I bought a new Canham 5x7 on the bay, cheap, and have build a 4x5 field already. Although I have a Beseler 45 I want to make a 5x7 and or an 8x10 enlarger. I have two cold light heads, one 5x7 and one 8x10 that I have collected for a couple of years. Got the lenses and now feel inspired to go for it.
Regards,
tr
When I switched from 4x5 to 5x7 I bought a Zone VI VC head and built an adaptor to use it on my old 45M. It worked very well. I had already detached the enlarger from its base and anchored it to the wall for more elevation. My biggest problem then was making 8x10 prints. For that I had to set my easel on a box to get it close enough to the lens for the small enlargements. Eventually I bought the rest of the Zone VI because I got tired of the little issues but the adaptor was actually a pretty good solution and had it not been for the range of sizes that I print (8x10 up to 28x38) I might still be using it.Originally Posted by Turner Reich
Jerome
I have an old Gundlach Korona View, 5x7, in pristine condition, with a 7 1/2 Wollensak Raptar f4.5. I just recently got it in eBay and have been learning how to use it. (it's my avatar, to the left of this post) I shot paper negatives first, then loaded my sheets backwards on my first film try and got underexposed shots (some were usable and good, though). Then, on a trip to Baton Rouge, Louisiana, I really tested the camera. It is beautiful!
I have about 15 medium format cameras, Six Rollei TLRs including the Vb and the Art Deco, Yashica 635, Mamiya C220 system, Meopta Flexaret, Graflex TLR and Ciro-Flex and other TLRs, a Russian Salyut C system (medium format) and several 35mm SLRs and rangefinders, but had always wanted to shoot LF. It's a dream come true!
I am currently working on a 4x5 reducing back for the Korona, to which I will incorporate shift and rise (same function, but it is a revolving back), and a lensboard to give me swing and tilt (I will shift using the back and the swing. It's a pretty cool design on paper, but I have yet to try it (bought the hardware today). Also an adapter to use an Omega B2 head and condenser set I have on the 5x7 (primarily for 4x5, since it will vignette on 5x7). Just received a 7 1/2" (180mm) and a 162mm I won very cheap on eBay (actually a set of 7 enlarger lenses, the other 5 are 35mm and sub-miniature) so I will have to make lensboards and test those on the 5x7 enlarger (it has a 210mm now) and to see if I want to use the others in my Omega B8.
...having fun!
Yes, I looked at Adams' enlarger (it is shown in The Camera). The magnet idea is good, but it would mean not using all the paper to the edge... Also I don't have that much space in my darkroom (it's roughly 8"0" x 11'-0" by 8'-6" high), so a horizontal setup was out of the question - the 11'-0" dimension includes the space under my 2'-0" deep 'wet' counter which I cannot see using for the enlarger.
Parallelism: still looking into the issue. I built a micro-focus mechanism that raises/lowers the baseboard to help with critical focus and bought a grain focuser and have looked at one or two negatives trying to detect out-of-focus areas, and the results have been good, but I have not had that much time to really find out. I bought bronze bearings to replace the plastic bearings for the two rods that keep the lensboard from moving side-to-side, as they bind a bit while focusing with the upper focuser, but have not had a chance to install them. I hope they will solve the binding problem, which has to be causing the lensboard to not be parallel to the baseboard at the point they bind. I will report.
Last edited by Rafael Garcia; 20-Sep-2006 at 17:38.
Just finished testing a 180mm lens. I had to move the brackets around quite a bit to compare the range of enlargements. Glad to say it was easy and the flexibility of having the 210 and the 180 is fantastic. Now I can get 8x10s that cover most of the 5x7 negative or blow a tiny sector up to the same size!
On parallelism I have some ideas. I am adding a threaded rod bearing/support point at the bottom of the support truss. I think this will get rid of the binding that throws the lens platform out of plane while macro-focusing. It hasn't been a problem in practice because I've been nudging it along, and printing with very small f stops, but this should make the issue dissapear. I will also affix three small retractable tape measures to the lens platform struts so I can pull them down before enlarging to quickly verify the lensboard is parallel. The baseboard focuser continues to be a great help in micro-focus, as it is much easier to use while looking at the image on the easel, and the movement does not bind at all.
I was asked by private massage if I had plans drawn for the enlarger. After spending a long time in my response, I think it would be good to share the info here. I hope to draw plans sometime, but I just have too many other things going on right now. This description is the best I can do (there are post length limits, so this may be a multi-post posting):
Part 1:
Cold Head - a wooden box about 24"x12"x6" (I'm working from memory here-the enlarger is in the basement and I'm upstairs). I screwed in six under-counter fluorescents on the bottom, in three rows of 2, wired in series after painting the inside white. The cover is cheap translucent 2x4 fluorescent fixture lens material (the light diffuser) from the hardware store, cut to fit the box and screwed on. I picked the plainest, smoothest type I found so there would be no texture for the lens to pick up. It might be better to screw the diffuser to the bellows unit instead of to the box as I did for ease of access (tube changing) in the future.
Bellows/bellows platform - I made a 3/4" thick "u" shaped platform, using a table router to join the wood in tongue and groove fashion and glued the three pieces. The center of the "u" is also routed to accept the 5x7 picture frame that I made the negative carrier from, sitting on a ledge deep enough for the frame to be flush with the top of the "u". The "u" is as long as the light box, and is square (so it's 2'-0" x 2'-0") I added two pieces of wood molding to hold the light box on top (it just sits there - I taped the sides with black gaffer's tape to seal the light coming through the sides). The bellows I made from a cheap vinyl roman shade-type window blind, the kind they sell for when you move into a new place and have no curtains yet. I just cut four 12" strips, estimated how long they had to be by half-stretching them and cutting the length a bit longer than the focal length of the lens I had, which was a 210mm lens, about 9". I taped the corners together without trying to make them light-tight, just to make a strong connection so that the bellows would be pretty rigid. The bellows is 12" square. I taped the top and bottom to two 1/8" plywood frames I had cut, with the center opening 12"x12", and outside to outside about 13"x13". I used black gaffer's tape for all of this. I sprayed the bellows inside and out with black spray paint for vinyl patio furniture. The reason I didn’t worry about light tightness is that I took a piece of taffeta fabric and wrapped the whole bellows with it, and taped it to the top and bottom bellows frame. The bellows keep the fabric from folding into the path of the light; the fabric keeps the light from leaking out. The top bellows frame is screwed to the underside of the "u" platform, centered under the negative carrier slot.
Last edited by Rafael Garcia; 7-Oct-2006 at 22:20.
Part 2:
The focus platform - This is what I am trying to improve. What I did was to build a 1/8" plywood square platform, 13"x13" and screwed/glued three short legs to it, out of 1x2 lumber. There are two in the front, parallel to the sides, along the edge and projecting about 6" and one centered in the back, again parallel to the sides. I placed this on top of the "u" platform and drilled 3/8" holes through the end of each leg and through the "u" platform below, so the holes would align perfectly. I cut a 4"x4" hole in the exact center of the focus platform, which is the center of the bellows when the whole thing comes together.
Putting the enlarger head together - I nailed a threaded insert for 3/8" coarse thread to the top of the three holes of the "u" platform, and took a 24" length of 3/8" threaded rod and inserted it through the hole in the back leg of the focus platform. I locked the platform in place the same distance from the end of the rod as the maximum stretch of the bellows (plus a couple of inches) by using two nuts locked against each other above and below the leg, with a washer between the pairs of nuts and the leg, top and bottom. This should be snug, but not tight enough to keep the rod from turning in the hole. I then threaded the rod through the threaded insert in the "u" platform, and added a knob (with another locking nut tight against it) at the bottom end of the rod - this is the rough focus knob. For the two legs/holes in the front side I got two carriage bolts, 10" long and 3/8" diameter and two bronze bearings for 3/8" shaft (the photos show the original plastic bearings - I have the bronze bearings but have not actually installed them yet). I enlarged the holes in the two front legs to take the bearings, inserted the bearings and ran the bolts through the bearings; head down, to two threaded inserts on the top "u" platform holes. I tightened the carriage bolts. The two front legs should slide up and down the bolts when the rough focus knob is turned. I took this all apart and screwed the bellows in between the top and bottom platforms using 1/2" wood screws, then put it all together again. I added a length of wood to the back leg of the lower platform, at the butt end, facing down, just short of the knob, and took two pieces of aluminum bar of equal length, drilled a hole in each end, bent them to fit, and connected the end of this last piece to the two front legs to form a triangular truss shape - this adds rigidity to the lower platform. This is also the weak point i'm working on, because it is still not rigid enough, and the two front legs bind on the carriage bolts when I focus. I think that if I add another bearing point to the back leg, at the bottom of the piece attached to the "butt", so that the rod goes through the leg twice, the connection will be more rigid. Or, as a different approach, I'm also considering using the same threaded rod from the back on all three legs instead of the front carriage bolts, and rough focusing by turning all three. This makes sense because the baseboard can be made to do most of the focusing, so the bellows extension and rough focusing would only be done when changing lenses or enlargement size.
The lensboard - I built an extended lensboard by building a 4"x4"x4" box with a round hole to let the rear lens elements pass through and three aluminum clips I found in my workshop (they were clips for holding sinks to countertops, but almost anything will do) to hold each lens' lensboard (if you have more than one). I built it because my bellows ended up too short. It's simpler to build your bellows longer and not do this. I fastened the extended lensboard to the underside of the lower platform, under the 4"x4" hole. The inside of the 4x4 box is painted black.
Last edited by Rafael Garcia; 7-Oct-2006 at 22:34.
Part 3:
The baseboard - I took two 2’-0" x 2'-0" pieces of 1/2" plywood, built 4" high sides on the outside edge of one so that the other one nested inside, and drilled a 3/8" hole in the exact center of each one. I made a "wheel" out of the same 1/2" plywood (a 6" square with corners cut off) and drilled a 3/8" hole through its center. I took a 6" length of 3/8" threaded rod and locked the "wheel" on one end of it with a nut and a washer on each side, tight so that the rod would turn when I turned the wheel. I then passed the rod through the hole in the bottom plywood panel (the one without the sides), putting double nuts/washers under and on top of the panel like the back leg of the top platform (so the rod can turn in the hole). I glued blocks of camera case foam (but foam rubber will also do) 4" thick, on the corners of the lower board, and installed a 3/8" threaded insert in the bottom of a drilled block of wood screwed to the bottom of the top panel (the thicker this block the more focus movement you will get, because the threaded rod will start sticking up through the hole in the top panel and pushing your easel from the bottom if this block is too thin, signaling the end of focusing). Turn the threaded rod (using the "wheel") through the insert on the block attached to the top panel and the panel will move down, compressing the foam blocks on the four corners of the bottom panel to stay level and vibration free, and giving you fine focus close to your easel.
Final step - Hang it all from the wall using heavy duty brackets and standards screwed to the top ("u") platform and the bottom baseboard panel. Mine are 6'-0" long, 2'-0" from the floor. With a 210mm lens, the baseboard at counter height, and the enlarger head close to the top of the standard, the 5x7 negative is longer than the 2'-0" baseboard! Just imagine if I lower the baseboard to the bottom of the standards!
Hmm...not going to spell check this... took longer than I thought! Hope you can understand all of this.
Rafael
Last edited by Rafael Garcia; 7-Oct-2006 at 22:37.
One small detail: The bellows are attached to the "u" shaped negative carrier platform and to the focusing platform using the same plastic clips that came with the under-counter fluorescents. They can be seen in the photos. No sense in wasting good parts!
Also: The negative carrier is a 5x7 metal picture frame with an extra sheet of glass and no back. I hinged the top sheet to the bottom one with gaffers' tape, and made a temporary handle with gaffers' tape also (but I've never gotten around to making a permanent one). I also made a flap with gaffers' tape so that I can cut off the light coming from the negative carrier slot (the center of the "u") when exposing.
Last edited by Rafael Garcia; 8-Oct-2006 at 12:37.
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