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-   -   Review of a 10” x 8” Bulldog Camera (http://www.film-and-darkroom-user.org.uk/forum/showthread.php?t=432)

Dave miller 24th December 2008 01:53 PM

Review of a 10” x 8” Bulldog Camera
 
This is the tale of the construction of a working camera.

After trying to order through several dealers without success Pinhole Solutions were found to hold stock and they took my order and arranged delivery of the kit for an agreed date, and the postman obliged; a good omen?

The components were neatly and securely packed in a plain but serviceable box adorned only with a simple illustrated label.

http://www.film-and-darkroom-user.or...dog/10x8-1.jpg


On opening the box the odour of MDF pervaded the room; it had the unmistakable smell of unfitted wardrobes about it.

http://www.film-and-darkroom-user.or...dog/10x8-2.jpg


An instruction book was evident so what better way to begin than by looking at that. The cover illustrates the finished product, it’s always helpful to see what the finished article is supposed to look like. The manual’s inside cover contains a list of adhesives and tools not included, nothing too daunting and all available at the local hardware shop. There also an all important parts list, so I spent a quarter of an hour checking and identifying all the components to ensure there were no shortages; which their weren’t. One surprise was the inclusion of a ¼” tripod plate, for some reason I expected it to be a 3/8” threaded unit, much more suitable for this size of camera. The all important metal work looked serviceable if not terribly pretty in its zinc plated finish. When I looked at the quantity and variety of the metalwork components provided that I began to see where the money has been spent. One thought crossed my mind as I picked up one small bag that contained five knurled knobs; heavy! Could a useful weight saving be made on manufacturing these five 40 gram units out of aluminium without a significant price increase, it could be that they are brought-in items not specifically made for this kit?

Two shrink wrapped packs of 9mm thick MDF components are included. It is obvious that these are laser cut, so a high degree of accuracy was anticipated, but I wondered why the holes had not been fully cut out, the redundant centre piece is left in situ, held only by a slither of material. Maybe the answer would be revealed during construction, were they in fact required? (it wasn’t, and they weren’t) Also within one pack, safely shrink wrapped within its eventual frame, was found the ground glass screen. I removed this and taped it, together with the pinhole lens, still in their protective wrappers, to the bellow packet for safety, and put them to one side.

I had wondered at the dark edges evident in the various illustrations of the completed camera, now the answer was revealed to me. They result from the laser cutting process; they are literally the burnt edges of the board.

The instruction book is reasonable clear, and short enough to inspire some confidence of actually reaching the end. Each page contains simple instructions accompanied by clear illustrations; in fact I’m impressed with their clarity; only time will tell if they are comprehensive enough for me.

It’s time to go shopping for the glue, and then get stuck in; ouch!

It is necessary to trim the debris left when breaking out the various cut-out waste pieces. I used a small craft knife for this, also a sanding block is required for any of the external edges that needed attention. Don’t get the idea that this was an arduous task for it was not, the standard of cutting really is very good, and it took only minutes to remove what are little more than corner burrs.

The instructions lead me through the assembly of the main frame unit that forms the back and base without drama.

http://www.film-and-darkroom-user.or...dog/10x8-3.jpg


I did find that a little white glue goes a very long way, and quickly learnt to reduce the quantity after making the first joint.

http://www.film-and-darkroom-user.or...dog/10x8-5.jpg


Initially I had reservations regarding the structure maintaining its squareness during construction, but this was soon dispelled, as I found it self-aligning to a great degree of accuracy, surely an indication of a good design.

Running through the side plates and across the baseboard is a steel rod which will eventually work the geared focusing mechanism. This rod also passes through a couple of reinforcing block. I found the predrilled holes in these blocks where a mite too small, and required a few minutes work running a spinning drill bit back and forth through them before the rod could be inserted comfortably.

http://www.film-and-darkroom-user.or...dog/10x8-4.jpg


Fitting these blocks completed the structure of the main frame, which had taken about an hour to this point.

I now processed a structure that with a fair degree of imagination, and a lot of help from the manual’s illustrations, could convert into a camera, an indication that there was still a lot to do.

The next step was to mix some of the epoxy resin; I had brought the slow drying variety to give myself time to make mistakes! There are four steel bars that have to be glued into position, two of which are gear racks for the focusing stage, and the other being two small bars that form spacers for the focusing screen. Since the instructions specify a flat surface for these operations I prepared a sheet of glass by covering it in cling film.

http://www.film-and-darkroom-user.or...dog/10x8-6.jpg


In addition four small brackets have to be made, each comprising a small length of rod glued to a preformed section of strip steel. Nothing too onerous, and all being set aside for a day for the adhesive to cure.

Fitting the multitude of iron work came next, commencing with the spring back.

http://www.film-and-darkroom-user.or...dog/10x8-7.jpg


http://www.film-and-darkroom-user.or...dog/10x8-8.jpg

My electric screwdriver came into its own here.

Trial fitting my Fidelity film holder into the back showed that it would not slide all the way in, becoming stuck with a centimetre to go. The locating ridge on the film holder was catching on the finger handles of the spring back. The solution was to chamfer the inside of the handle so that the locking ridge could bounce it out of the way.

http://www.film-and-darkroom-user.or...og/10x8-17.jpg


In spite of this modification the design needs reconsidering and amendment because the top bar of the Fidelity film holder also fouled the camera body at the front which pushes the holder back a couple of millimetres. Probably not critical for pinhole work, but no help when trying to focus a through a lens.

Having assembled the front stand

http://www.film-and-darkroom-user.or...dog/10x8-9.jpg


I became quite certain that it is too flimsy to support my 300mm lens in a Copal 3 shutter. With care it should be ok with the 240mm in a Copal 2 shutter, and of course the pinhole plate provided would not stress it.

The recess in the lens board proved far too deep for the pinhole lens plate supplied, which in itself was oversize, and had to be trimmed to size. The recess was also too deep for my metal Toyo lens plate which required some 2mm of packing to stay in place.

The ground glass screen fitted easily and securely.

I had assumed that the contact adhesive was required to fix the bellows to the camera frame. The instructions however state that epoxy should be used for this purpose, taking this to be a typing error I used the contact adhesive I had purchased for that job, it worked well. I protected the bellows with strips of card during the messy operation of glue spreading.

http://www.film-and-darkroom-user.or...og/10x8-13.jpg


http://www.film-and-darkroom-user.or...og/10x8-14.jpg


When the adhesive had gone off I removed the card and joined the bellows to the lens board and back standard.

Suddenly, apart from painting, it seems to be finished, after a total working time of about 6 hours.

http://www.film-and-darkroom-user.or...og/10x8-15.jpg


So what are my thoughts now that it’s finished?


My worry about the stiffness of the front stand proved, well not quite groundless. It’s true that my 300mm lens in a number 3 shutter is a bit much for it, but one has to remember that it weighs about a kilo.

http://www.film-and-darkroom-user.or...og/10x8-16.jpg


The usable bellows draw range of 125mm to 390mm seems reasonable, I say usable because any attempt at closing the bellows further pushes the front stand forward. In any case the recommended setting for the pinhole lens supplied is 125mm, and I haven’t got a wider lens than my 240mm that will cover this format.

http://www.film-and-darkroom-user.or...og/10x8-18.jpg


The minor niggles I’ve mentioned should be addressed by the makers, correction of these will make for a much more satisfying product.


I suppose the main question must be, do I consider the time, effort, and of course cash well spent? As a matter of fact I do, and recommend it to anyone contemplating entry into this format who is reasonably happy using basic craft skills; especially if they want to produce 10x8 pinhole contact prints for a relatively minimal outlay, but with the option of using a shuttered lens later.

Do Ebony, Shen Hao, or Chamonix have anything to worry about? No, not a thing!

Trevor Crone 24th December 2008 02:22 PM

Excellent article Dave. Why not take some pictures with the camera and send this into B&W mag. to recoup some of the cost?:)

Dave miller 24th December 2008 02:29 PM

Quote:

Originally Posted by Trevor Crone (Post 4221)
Excellent article Dave. Why not take some pictures with the camera and send this into B&W mag. to recoup some of the cost?:)

I have a DDS loaded, and pinhole fitted. I will take and post pictures just as soon as we get something that passes for light here in Middle England. :(

I had intended offering to swoop the Bulldog for the old Ebony that you insist on lugging around;;) the Bulldog is so much lighter; I'm sure you would love it.

Barry 24th December 2008 02:34 PM

Nice article Dave.

I read your comments regarding the film holder, is it in too far?

Go out and make some (long) exposures

Dave miller 24th December 2008 03:13 PM

Quote:

Originally Posted by Barry (Post 4225)
Nice article Dave.

I read your comments regarding the film holder, is it in too far?

Go out and make some (long) exposures

No, in the position shown in the picture the edges of the DDS line up with those of the back panel aperture.

Barry 24th December 2008 03:18 PM

Quote:

Originally Posted by Dave (Post 4234)
No, in the position shown in the picture the edges of the DDS line up with those of the back panel aperture.

Can you cut out the MDF to get a light tight fit?

Dave miller 24th December 2008 03:29 PM

Quote:

Originally Posted by Barry (Post 4236)
Can you cut out the MDF to get a light tight fit?

The light trap strip near the top of the DDS is sitting sufficiently deep into a milled slot to provide a light trap. Only use of a bright day will demonstrate if this is so.

Barry 24th December 2008 03:35 PM

Bright Day! That could take a while then :D

Nice job though Dave :cool:

B&W Neil 24th December 2008 04:27 PM

Well done Dave - this is a very interesting and informative article for FADU.

Neil.

Trevor Crone 24th December 2008 06:03 PM

Quote:

Originally Posted by Dave (Post 4238)
The light trap strip near the top of the DDS is sitting sufficiently deep into a milled slot to provide a light trap. Only use of a bright day will demonstrate if this is so.

Dave, you might be able to locate any light leakage by taking the camera into the darkroom and placing a bright light in the camera through the front standard. I did this with their 4x5 version, which revealed some light leakage at the back of the camera. It's also a good way of checking bellows for any pin holes.

Dave miller 24th December 2008 06:39 PM

Quote:

Originally Posted by Trevor Crone (Post 4250)
Dave, you might be able to locate any light leakage by taking the camera into the darkroom and placing a bright light in the camera through the front standard. I did this with their 4x5 version, which revealed some light leakage at the back of the camera. It's also a good way of checking bellows for any pin holes.

Thanks Trevor, I shall try that.

BobRob 30th December 2008 01:10 AM

Thanks for the article Dave.

Looks very good too,don't think you should paint it at all.

Bob.

Argentum 30th December 2008 03:09 AM

Quote:

Originally Posted by geetoo (Post 4391)
Thanks for the article Dave.

Looks very good too,don't think you should paint it at all.

Bob.

First few drops of rain you get on that fibre board and it'll grow to be an 11x14 :D

Sandeha Lynch 25th January 2009 10:36 AM

Congratulations on the building, Dave. Just don't drop it. :eek:

I gather grey camo is very popular these days.

seoirse 28th February 2009 09:52 PM

Great review Dave.

Would it be feasable to swap the mdf parts with solid wood (before assembly by using the mdf parts as a template) to get a more robust camera, would you say?

Dave miller 1st March 2009 07:32 AM

Quote:

Originally Posted by seoirse (Post 7505)
Great review Dave.

Would it be feasable to swap the mdf parts with solid wood (before assembly by using the mdf parts as a template) to get a more robust camera, would you say?

I don't think that would be worth the effort, this project is, I think intended as an introduction to large cameras.


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