I have just converted a Polaroid 250 to 4x5 making it a very light weight field camera. Is there any interest on how I did it?
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I have just converted a Polaroid 250 to 4x5 making it a very light weight field camera. Is there any interest on how I did it?
Absolutely I'm interested in hearing how you did it.
congratulations on your success!
Of course !!
Ditto
sure..lets see a pix of it
And why?
If your wondering why the interest... for me it's to see how it was done because as I approach retirement I might need another project and I have an old 250 sitting on the shelf. Why not???? If it's easy enough than maybe that's the solution to my increasing difficulties of carrying a 4x5 Speed Graphic. (or... maybe I just need to spend more time at the gym).Quote:
Originally Posted by Bob Salomon
I just retired and it too was a project I wanted to do. I live at 7,000 feet ASL and lugging 40 pounds of camera equipment is just not macho anymore but I still want to take photos using a 4x5 camera.
I started the conversion last Thursday and have one more hour mounting the film holder back plate onto the converted camera after I find the right springs,hopefully in the AM.
The camera is very light,as in "you have to be kidding" light. I'm hoping to have the camera,tripod,light meters,film holders and the rest under 15 pounds which looks very doable.
I recently dumped windows 10 and all its problems and went to the Ubuntu OS and am learning Gimp photoshop type program. I have most photos ready to add to the post.
As soon as I can get my ducks in a row I'll post the DIY this week.
Anyone who can use common hand-tools and not end up in the ER can do this conversion.
Thanks for the interest.
Would be interested to see it, sounds like a DIY Chamonix Saber (which is not an easy thing to replicate).
Part 1:
I decided to convert a Polaroid 250 camera to 4x5 cut film for no other reason than weight. Where I live everything is uphill, both ways. While many have done the 100 series of Polaroid cameras I wanted it to be as light as possible, with tripod,exposure meters ,film holders,dark cloth and the like I wanted to keep all the goodies down to less than 15 pounds or less while on the trails. I may have done just that.
I found a mint P-250 for under 20 bucks delivered and proceeded to disassemble the camera of parts that were no longer needed. The amount of weight removed from the Polaroid film packet device was more than one would think.
Attachment 175375
Many of the original parts are held in place by rivets. They are easy to remove by using a drill bit larger than the rivet head. You just drill off the head and the rivet falls out.
Some screws are loc-tight’ed into the body. A blast of Brake Cleaner or a dab of Acetone will soften the Loc-tight and the screw will come right out.
Attachment 175376
Once the roller back is removed remove all of the battery holder,its support and the wiring. you will be covering this later on.
The spring loaded latch on the camera bottom and its parts are removed. The latch itself will be epoxy-ed in place for looks. The hole at the top will be filled with epoxy.as well.
Attachment 175377
The cameras original camera tripod mount cannot be used because you will be adding plywood that will block its use. I turned one from aluminum that is higher than the wood and is very strong. The original 14x20 threaded hole is used. I also turned and knurled another piece of AL and secured it with three #6 screws.
The front cover with its lens and sensor is removed.There are four long flat head screws that hold the cover in place, SAVE these screws you will be using them again. Note the length as well.
The front cover will be cut into thirds as you will see.
Remove all of the electronics and its wiring. Pull the power wire through the upper right hand corner of the camera.
Attachment 175378
Part 2 to follow later.
Part 2:
Remove the Range finder. It is held in place by flat head screws that can be reached by a small flat bladed screwdriver. There is one rivet that is part of the lever system that must be drilled out. A 6" long 5/16" drill makes it an easy job. Set the RF aside in a safe place.
The now stripped frame of the camera will have a Hobby plywood frame made to take the cut film holder. Two vertical stanchions are made and glued in place along side of the vertical ridges that are case into the housing. The wood is just thick enough to bring the cut film holder frame level with the back of the camera body. It will be obvious to you when you place the wood next to the cast ridges. These stanchions will take all of the forces loading/unloading the cut film holder. Use on a quality epoxy to glue them into place. Screws are not needed. JB Quick 5 minute epoxy is ideal and super strong. Use an acid brush or the like to spread the epoxy on the wood. Use only enough to glue the wood in place. Clamp in place with enough force to hold the wood in place,not ooze out the epoxy. Lever clamps and light close-pin clamps work well. you can take the clamps off in an hour.
Attachment 175391
As the two stanchions are setting up now is a good time to open up the old lens mounting hole. You can use a high quality Hole saw but a Dremel tool with a sanding drum is just as easy and allows small adjustments as needed. Remember as stated to allow the room for your locking ring. Make sure you can mount the lens without damaging the bellows on the inside. Make sure you have the bellows plate screwed back onto the back of the lens plate. It is steel and cuts easier when attached to the lens plate. When grinding/sanding the hole larger just use easy circular motions. It will take about 30 minutes to do.
The casting is thick enough you could do a surface mount or even thread the hole. The surface of the lens holder is not flat,there are raised portions than need to be ground down. Easy with the Dremel tool.
Once you have the hole enlarged for your lens, do a trial fit. the trip lever will be on the left. Make sure you can move all the lens settings/levers.
Attachment 175392
Attachment 175393
You trip lever may or may not be like mine. Fuji and Nikon lenses are very easy to trip,my lens required a dog-leg tripping lever. I had to mount a wood block to allow a pivot point for the tripping lever.
Attachment 175394
Part 3 to follow
Part 3:
The wooden pivot block is glued in place. JB Weld is used.
Attachment 175432
While the block is setting up the Range finder is prepared. The wood block is just thick enough to have the view port clear the wood cut film holder.
Attachment 175433
The range finder has three screws holding it's cover on. The two front screws must be reachable in order to do repairs if needed. The third back screw can be left off as it will be covered when glued down.
Attachment 175434
A trial fit is used before it is glued down.
The Range Finder's range lever will be moved by a steel "L" bracket cut from a 22 gauge piece of scrap. The spring on the range finder is stiff. Aluminum was found to bend over time causing the range finder's zero to be lost. A common number 6 screw and nut is used in the hole drill out in a previous step. This bracket is used to fine tune the zero by bending when the camera is complete and very easy to do.
Attachment 175435
Part 4:
Once you have glued the Range Finder in place you can now mount the cut film holder back. The two vertical stanchions are now set and will support the cut film holder ( CFH ) frame.
The CFH is a simple three sided frame built to hold a CFH with a slight friction fit. You want the thickness of the wood to be just to clear the thickness of the CFH. Taper the loading ends of the wood to ease the CFH insertion into the frame.
The CFH is not glued into place until you have verified coverage of the wide open lens.
A Ground Glass holder is used with the aid of a dark cloth to adjust the holder to the dead center of the projected image of the lens.
Attachment 175436
This is a simple ground glass holder made from a Dollar Store plastic picture frame and "ground" using valve grinding compound" on a dead-flat surface. The frame is hobby plywoods as well. Keep screws for the glass holder below flush. Easy to do and unbreakable.
The lens is opened up and a distance object is aimed at and the frame is zeroed. The frame is marked and then glued in place and allowed to dry. ( camera is out of focus)
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Very interesting. Thanks!
A related question.
Which Polaroid model is the best for a 4x5 conversion as far as coverage goes?
Any model that cover all of the negative?
Yes, thanks for the demo. Very cool!
I notice that some hobby wood is just right for LF creations.
Of course, your micrometer may vary. That's not for OP, but other inquiring minds.
They all have the same lens/bellows so all should cover 4x5 about the same (in the 100-series polaroids, which the 250 is part of)
As stated above,it the back of the camera can be converted to a flat surface by wood fillers I see why none off them could not be converted.
If the camera has the Zeiss range finder your pretty much good to go.
Part 5:
The range finder is glued into place once you have verified the lens zero. The two nubs on top of the frame provide a good lateral support of the wood block. They are spaced far enough apart for Range Finder lever adjustment. By moving your mounted RF left and right you just bring your hand made bracket to just touch the RF's actuator lever. A very little movement of the RF lever will effect the zero of the device. That being said,you made bracket mounted on the two focusing arms will be bent slightly to find the lens/ RF zero. It very east to do.
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Part 6:
Now for the hardest part. The shutter tripper. As stated above the Fuji and Nikon lenses are so east to do I'm not going into it.
The Rodenstock lens is the exception. It has a long throw tripper and the Polaroid red shutter button has a short throw. You have to make a mechanical advantage device. I tried several shapes and materials to be used to find which worked the best.
Things to take into consideration are:
How far does the lens trip lever have to move?
How far must it reset in order to re-cock the lens?
Is there enough return spring force to allow the cameras exposure button to reset?
While this sounds like " I can't figure it out,just forget it" it really is so easy to do if my dogs had thumbs they could do it!
1. Rotate the lens in the front standards hole until there is enough room for the lens trip lever to move. You do not want the trip lever to go father down towards 6 o'clock than 7 o'clock. This will prevent the device you will make from going behind the lens trip lever.
The wooden pivot block has been epoxied in place and has set up. The casting ridges will help hold it into place.
Attachment 175489
I'm using stiff wire to go around the shutter trip blade of the camera itself. By using a stiff wire you can "fine tune" the exact tripping point of the shutter be shortening or lengthening the throw of the wire. Very simple to do .
Now the hard part made the simple and easy way. You need to make a dog-leg lever to move the lens trip lever. The easiest way to move a resistive object is my a wheel. This allows a constant,smooth fully controllable force. You will have tools in your possession to bend the correct radius. A wooden dowel,a drill bit 1/2" or larger, just about anything round that can take the force of you bending the dog leg lever.
I have found Aluminum is NOT a good material to use. It does not like to be bent,adjusted and under many "trips" of the shutter it broke. You know it will fail for the best shot of your life exposure.
I found a scrap piece of 22 gauge steel sheet. You can bend it several times and find tune the throw of the lever way before the steel shows signs of stress cracking.
This was a concept test lever. Aluminum,it did not hold up well but got me thinking in the right direction.
Attachment 175491
Part 7:
Now that I have my ducks in a row for the tripping of the shutter, I have made the linkage to trip the shutter and allow the lens trip lever to return. As it turned out after hours of tring angles and dangles,I had to add a small return spring. Not a big deal as the force needed to always return the lens lever was slight. a Ball-Point pen spring would be more than enough.
Attachment 175492
Remember, you MUST always allow the lens trip lever to reset or you cannot re-cock the shutter.
All speeds including "B" work as they should.
All parts are at the same height as the cameras cast lens holder. The cover is fairly open and you do have some wiggle room it your parts are a little high. Your now are ready to finish the camera.
For ecstatics I did use parts of the front cover. I used a mill to cut the casting but a good hack saw or coping saw can be used.
All I wanted to cover was the tripping device and balance out the front of the camera. Nothing fancy,just for giggles.
Attachment 175493
The cover pieces are held into place by the three long screws you saved. A dab of contact cement on the ridges will keep them from moving is bumped. Not really a big deal. As I said the cover is for looks.
There are two "slits" in the covers for the original shutter and cocking levers. you can fill them in,or leave them alone.
Attachment 175494
Part 8:
The final part that needs to be made is the wooden Cut Film Holder spring back plate.
All this does is to apply a force on the CFH to keep it in place and light tight. It must allow you to cam the CFH into/out of the CFH frame you made.
I could have gone fancy with all brass fitting ha screws, but for this article I used what I had on hand. The city is a 50 mile round trip.
The corners of the film back will have thumb screws and ligh springs. How light?.... 6 ounce compression force each. Just under two pounds of force total. That is all that is needed.
All of the wooden parts are painted flat black. Walmart in it's hobby section sells little plastic four/six ounce Craft Paint for 50 cents a bottle. This paint will not flake off and seems to hold up very well.
One bottle is more than enough for several coats of paint if needed.
Attachment 175495
What I did that is not mandatory,but cleans up the back of the camera, is to fill in the two gaps that used to hold the film pack. I just used scrap wood and glued it into place and covered what was left with 1/8" plywood.
The camera is ready for use and it works well. I have only taken one exposure so far using X-Ray film and Microdol-X developer. I was trying an experiment that flopped but I got an interesting image.
F:64- 5 second exposure. Microldol-x diluted 60:1. One hour stationary development.
The silver halide grains clumped together giving the effect of almost Half-Tone images of a Newspaper. Hey, I tried.
Attachment 175496
The only disadvantage of this camera conversion is the close up minimum focusing distance. It is 43 inches. By your choice on lens you could do much better I'm sure.
I hope you get the bug to do a conversion as I did. It was not hard and in total it only took me 14 hours to figure it out and get it right. It could be done to the extreme for unparalleled quality and beauty, but I just wanted a very light 4x5" camera that worked and did not cost as much as a used car.
Oh yea, the camera is still under two pounds.
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With the tripod, meters,film holders, dark-cloth, cable release, bungee cord and bag to carry the equipment* I'm under 12 pounds! Man anyone could carry that a very long trek for that photo you must have.
* tripod is very light. Carrying bag is hung from the tripod using the bungee cord and filled with stones or sand to keep it steady in a light wind.
I hoping to use the camera for our very short lived waterfall this spring here in the desert. It's a long hike,all uphill,both-ways.
Rob.
We await your images.
Good documentation.
I want to make one!
Hi,
I've been a long time reader of the forum, and inspired by Rob's original conversion I decided to try my own with a Land 340 and post (my first) a description. I've built a couple field cameras in the past, but none of those are handhold-able , and so I was really impressed by Rob's idea. I've also been looking for a cheap, light, handheld 4x5 camera for travelling, and considering those don't really exist - this conversion idea is perfect.
Unlike Rob tho', I decided to keep the original lens and auto exposure, and use the camera as a sort of point-and-shoot 4x5 for the moment. I do have a Ysarex 127mm that I will probably end up attaching in future, but at the moment I'm enjoying the camera's simplicity of use. The conversion is very simple (and a little rough) but only took a couple days. Most of that time was spent waiting for parts to be delivered because it's impossible to source some of the bits need locally (very small town).
Attachment 177226
The back is made of a 2mm piece of mount board with 3 pieces of pine cut and glued to make the "U" shape. To attach it to the body of the polaroid, I filled the channels the original door closed in to with wood filler, which made it easy to glue the 4x5 back onto. I also attached a homemade wooden handle to make it easier to hold the new body shape. I originally had some light leaks where the pressure from the elastic wasn't quite strong enough to hold down the filter, but the green felt you see fixed that problem.
Attachment 177227
The reason I chose to use the elastic is that I have also made a 6x9 roll film adaptor (for a normal 6x9 Rada back that I already have), which wouldn't have fit under a back similar to Rob's. I'm hoping to think of a better solution in the future, but for now this works ok and the camera is usable.
As I mentioned before the biggest difference with my conversion is that I kept the original lens and auto exposure. To add the 4x5 back the film plane was moved back a few cm which obviously meant the original 114mm wouldn't focus at infinity. To solve this, and after some trial and error, I attached a -1 dioptre (the power of which depends on exactly how far back you move the film plane) to the front of the lens using a 27-37mm step up ring and then gluing the dioptre to the front of that. It also has the advantage of allowing me to use normal filters on the front rather than the polaroid type made specifically for this camera, which are rare and expensive. To do this I also had to convert the camera to use 3 x AAA batteries, which are now housed outside the body in an adaptor that's stuck to the base of the body. This is necessary because the 4x5 back would cover the original battery housing making it impossible to change the batteries.
Modifying the focal length like this has also meant that the lens will cover a 4x5 neg.
Attachment 177228
Attachment 177229
I calibrated the rangefinder by turning a spare holder into a makeshift ground glass, which I can also use as a plate holder in future. It's a little harder calibrating the rangefinder than I had anticipated, but after a couple test shots it's getting there.
I've also made a cable release that fits over the original shutter button which, along with the cap for the magic eye, gives me a bulb setting for focusing (with the gg) or timed exposure. At the moment I'm using standard film holders, but I'm hoping to get a grafmatic, which should make the camera even better for travelling. Unfortunately they seem to be very rare here in the UK, so it may be a while.
I've managed to take a few shots with the camera, and it's as simple to use as I'd hoped. It's feather light, the rangefinder and auto exposure is accurate enough, and I've managed to make a couple lith prints from the resulting negatives already.
So I'd finally like to thank Rob for the idea and inspiration :)
Dafydd
That is really cool! I plan to really use my camera if this darn wind ever stops.
thanks, and I'm having a similar problem at the moment.
I have a couple sheets of slide film I'd like to use to give the auto exposure a real test, but spring is really late this year, so everything is still just grey and brown.
The winds have died down. I loaded up some Fuji X-Ray film and did a shot of a cactus in my yard. I wanted to check for light leaks and the lens depth of field. The closest the lens will focus with the cameras bellows is 4 feet. I placed the camera 3 1/2 feet away and used F:11 to see what the image would look like. No dark cloth,nor ground glass,just the range finder was used.
I'm still experimenting with development times and tray agitation. I had been using 9 minutes as a development time, this time I tried 15 minutes with no agitation after a five second wetting of the film. This proved to be too long but I did get an interesting film. I do not own a film scanner as yet that will take a 4x5 negative.
Attachment 177848
Now it time to play with my X-Ray film for correct exposure and development times.
My old tractor, 2 seconds F:45, Microdol-X for 12 minutes agitation 5 seconds every 60 seconds.
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looks like your camera is working well, and your focusing seems accurate : )
I'm currently travelling with mine in Lisbon and it's working great, well it seems to be, but I guess I won't know really until I get home.
But I will have to redesign the back a bit, it's a bit awkward to load the roll film back when on the move quickly.
I have a 250 also, but I use it as an alternative to a pack-film back on my 4x5 camera.
Cool Beans! I love the very light weight and fast set up. No pan nor tilt,but 99% of all press cameras were ever tilted either and the photos went world wide and are famous to this day.
I have several types of X-Ray film to play with. I'm finding while the X-Ray cassette phosphor screens were "fast" when struck with X-Ray photons, the film itself is not fast in as such as ASA number.
Once I find the real film speed and use a developer such as revamped Rodinal 100:1 to see if I can get the images I would like to see.
I just built a focusing back for my camera,while not instantly usable,It can be taken off/on in 60 seconds for that really important shot where focus is mandatory over F-stop for depth of field.
I look forward to seeing your images! What fun for such a 4x5 camera made from a Polaroid camera sitting in a closet for decades.
I also have a focus screen for mine made out of an old film holder so it also just slides in and out easy, but I decided to leave it at home because I didn't bother bringing a tripod on my trip.
It is great fun, and certainly an amazing way to use what would otherwise be an almost useless body. It is almost too easy to use tho', especially when using sheet film, I'm just snapping away as if I was using 35mm : )
now that our windy season is dieing down, I plan on do some foot work around the Anastazi ruins here in NM. I restored a 1948 Trail King motor scooter ( way before the Tote-Gote) used to prospect for Uranium that can get into places a horse could not. It can carry me and 500 pounds of equipment that is far more than I'll even need.
I still need to play with some X-Ray film types I have to see which type will give me the tonal range I'm looking for. Not having a negative scanner isn't helping much either. But I'll make do for the time being.
I'm hoping others do the conversion as it makes lugging all the heavy cameras and tripod an option for a fun day shoot. I have the camera, ten film holders and the light meter in a Gas Mask bag on one shoulder and the 70's Vivatar light weight tripod on the other. Even an old phart like me can carry the gear all day long with no problems.
sounds like a perfect trip to test the camera for real!
I hope some other people go for the conversion too, the camera might not be as pretty as the other polaroids used for 4x5 conversion, but they sure are much cheaper/more abundant than them. I paid about £5 for my working version and with the cost of materials I don't think I actually spent more than about £15 total : )
I just got back from my trip and I can say that carrying the camera, 4 film holders, a box of extra film, roll film holder and changing back for about 7 hours a day walking through the city was easy enough. So I reckon you should be ok!
This is an old thread, but I just did a 4x5 conversion on a pack film camera keeping the 114mm lens and using a 3d printed back. Instead of the -1 diopter lens to compensate for the film plane moved back 18 or so cm (I like this idea!), I moved the lens body back the same amount as the film plane, using 3d printed parts. Because standard 4x5 film holders are larger than a Polaroid body, and I wanted to keep this within the dimensions of a Polaroid camera, I designed custom 3d printed film holders which are only 107mm wide, but hold a 4x5 sheet of film. I posted the details at http://polaroids.theskeltons.org/pack4x5.htm
I found that the 114mm lens doesn't quite cover 4x5, with some vignetting in the corners. So I did a similar thing to a Polaroid 110A, which is a roll film camera with a 127mm lens which covers 4x5 fine. Details at http://polaroids.theskeltons.org/pack4x5.htm