PDA

View Full Version : 11x14 or 8x10 box type camera



pbryld
1-May-2012, 10:26
I am just getting into LF photography and want to do paper negatives (which I have a lot of other questions regarding).
It seems quite cheap and relatively easy. It is really practical as well, as I don't want to deal with enlargements.
I love the look of it too.

Now, a 8x10/11x14 camera is just too expensive. Maybe I could shell out the $2000 a 8x10 costs (I've looked around on eBay), but the 11x14s are just way too pricey. Being 19 and not having too much cash, I thought a box type camera would be a good solution to that problem.

I am debating whether to use a pinhole or a lens. It would be really nice to be able to meter my scenes, which is why I am considering a fixed lens.

How closely can a pinhole focus?
Does it just require some testing (in different lighting, using different exposure times) to figure out a table for exposure times?

How do I figure out which distance there needs to be between the lens and the film plane, in order to reach infinite focus and still covering 11x14?


I also want to shoot interiors and still lives. For this I really do need a real camera, don't I (except if I make several cameras)?


For the design, I was thinking of basically making a box with hole/cutout to fit a film holder (I would of course make this light tight), much like how one does with a regular camera.


Thanks in advance!

John Kasaian
1-May-2012, 12:04
Pin hole it, pal! Nothin' cheaper.

For me, the killer with 11x14 cameras was the cost of the film holders (never mind the film!)
8x10 dosen't need to break the bank. Make contact prints and you don't have to deal with the added expense of an enlarger. Over time you can build a decent 8x10 kit on a budget. Ansco 8x10 cameras are way under appreciated, IMHO. Pinholes in the bellows can be effectively patched with goop from Equinox Photo. You will require a heavy duty tripod and film holders---look around for deals, they're out there if you're patient. If you're shooting paper negatives a barrel lens is slow enough that you won't need a shutter. There is also x-ray film to explore.
Have fun!

jnantz
1-May-2012, 12:25
hi pbryld ..

i make cameras just like you are talking about ..
and have made ones as large as 11x14 and as small as 2x3 ...

the hardest part is making the paper-holder ...

if you want to do chemical free photographs
you can make it so it is like a view camera, so the lens + paper standard
move to correct for distortion, or to create distortion ...
the exposures are very long though, anywhere from 45mins to 6-7 hours depending on the light ...

have fun !
john

jcoldslabs
1-May-2012, 13:29
8x10 doesn't have to be all that expensive necessarily. I picked up a Kodak 2D 8x10 camera for $150. The seller said the bellows were shot and while the corners are full of holes I have yet to patch them. I just throw the dark cloth over the camera and have never had a problem. I've never built my own camera but it shouldn't be too much of a problem. Even foam core can work:

http://www.flickr.com/photos/dairequinlan/4300741225/

Best of luck!

Jonathan

jnantz
1-May-2012, 17:53
;) yeah mine have all been out of foam core too ... lots of fun !
john

jp
1-May-2012, 18:23
With a pinhole, everything will be in equal focus. Exposure will vary from calculated based on reciprocity of the film which is different for each film brand/speed.

If you build a box camera, you could use a $100 wooden 8x10 back meant for a kodak/b&j, etc... so as to have the holder receiver and groundglass. Otherwise study the cam system some of the pinholes use to hold film holder in place.

You should be able to buy a nice 8x10 for $300 without a lens. $50 for a film holder. Lenses could range from $1 for a magnifying glass, $100 for a reinhold wallaston, $400 for a shuttered 300-360mm modern lens.

pbryld
2-May-2012, 01:39
Thanks for the quick replies!

As far as the price of a 8x10 goes, I guess I'll have to be patient and wait for a good deal (perhaps on the sales board here, which I don't have access to yet).
If I were to purchase that, it would be fun to just make a 11x14 pinhole camera. I'll be willing to pay for a holder, even though they are a bit pricey.

How do I know how long the pinhole needs to be from the film plane so it covers 11x14?

I was thinking I'd use a post card with the thinnest needle I have.
Will the focal length be too high though? Is it better to use tinfoil?

David Lobato
2-May-2012, 06:30
I made an 8x10 pinhole camera from black matt board and black gaffer's tape. I simply taped a sheet of film on the inside back panel, about 10x12 inches. No film holder necessary. Use a piece of brass shim stock, available in hardware stores, for the pinhole. I may even have an extra piece of brass shim stock. PM me if you're interested. That 8x10 pinhole camera was the gateway to the Deardorff I now use. Seeing and holding an 8x10 negative you made is pretty awesome.

Peter Gomena
2-May-2012, 09:32
The diameter of the coverage for a pinhole is approximately 3.5 times the focal length of the pinhole.

Find a copy of Eric Renner's book, "Pinhole Photography: Rediscovering a Historic Technique". It will tell you all you need to know. Building your own pinhole camera is easy and fun, and the results can be amazingly good, especially if you contact print the negatives.

Peter Gomena

pbryld
3-May-2012, 12:42
If you're shooting paper negatives a barrel lens is slow enough that you won't need a shutter. There is also x-ray film to explore.
Have fun!

Yes, X-Ray film seems interesting as well for contact printing. The film seems incredibly cheap, even the huge negs (here: http://www.cxsonline.com/text/summarypage.tmpl?command=search&sn=386413&db=../databases/products.db&eqcategorydatarq=10011004&eqmasterskudatarq=[blank]&skusort=1&cart=13360692361296516&location=10011004&startat=1&max=15), but do you know the sensitivity of the film?


I made an 8x10 pinhole camera from black matt board and black gaffer's tape. I simply taped a sheet of film on the inside back panel, about 10x12 inches. No film holder necessary. Use a piece of brass shim stock, available in hardware stores, for the pinhole. I may even have an extra piece of brass shim stock. PM me if you're interested. That 8x10 pinhole camera was the gateway to the Deardorff I now use. Seeing and holding an 8x10 negative you made is pretty awesome.

I was just thinking that handling the film would be a bit easier if I just had to load the film in a holder (my "darkroom" is unbelievably small), but I get that it cuts costs, which can be used for other luxuries :-)


The diameter of the coverage for a pinhole is approximately 3.5 times the focal length of the pinhole.

Find a copy of Eric Renner's book, "Pinhole Photography: Rediscovering a Historic Technique". It will tell you all you need to know. Building your own pinhole camera is easy and fun, and the results can be amazingly good, especially if you contact print the negatives.

Peter Gomena

I would ask you how I know the focal length of the pinhole, but I hope the answer is in the book. I am waiting to receive it from amazon.co.uk :-)

Thanks!

Peter Gomena
3-May-2012, 21:34
Well, the focal length of the pinhole would be the distance from the pinhole to the film. When you read Renner's book, you will find a chart of optimal pinhole diameters for given distances to the film. If you know the diameter of the pinhole and the distance from the pinhole to the film, you can calculate your f/number. It's all in the book. :)

Peter Gomena

bvaughn4
4-May-2012, 05:52
I have only dabbled with a few pinhole cameras and shots, so I'm no authority on them, but google pinhole cameras. This link was quite handy to me: http://www.mrpinhole.com/calcpinh.php

Edit to add link to pinhole site: http://www.f295.org/site/

awldune
4-May-2012, 06:49
I have only dabbled with a few pinhole cameras and shots, so I'm no authority on them, but google pinhole cameras. This link was quite handy to me: http://www.mrpinhole.com/calcpinh.php

Edit to add link to pinhole site: http://www.f295.org/site/

I noticed that the image circles given by that calculator differ from Peter's 3.5x rule of thumb above. The calculator gives 240mm FL to get a 450mm image circle.

Don't know which is correct, the difference may be down to different definitions of "coverage" (falloff tolerance)

pbryld
4-May-2012, 07:01
Well, the focal length of the pinhole would be the distance from the pinhole to the film. When you read Renner's book, you will find a chart of optimal pinhole diameters for given distances to the film. If you know the diameter of the pinhole and the distance from the pinhole to the film, you can calculate your f/number. It's all in the book. :)

Peter Gomena

Great, can't wait to get it. :)



I have only dabbled with a few pinhole cameras and shots, so I'm no authority on them, but google pinhole cameras. This link was quite handy to me: http://www.mrpinhole.com/calcpinh.php

Edit to add link to pinhole site: http://www.f295.org/site/

What a need site, that mrpinhole! Thanks!

kurtdriver
4-May-2012, 08:55
Is the shape of the pinhole that important? Skink pinholes are done with a laser which is supposed to better because the hole is more round that using a needle. Is that true? I'm thinking of doing something similar, and wondering if I can adapt their system and if it would be a good idea.

Edit: This (http://skinkpinhole.com/wp/webshop/kamera-zubehoer-fuer-diy-eigenbau/skink-pinhole-pancake-for-diy-camera/) or this (http://skinkpinhole.com/wp/webshop/shop/grossformat/skink-pinhole-pancake-starter-kit-copal-0-verschluss/) would do it, but are they really better?

Peter Gomena
4-May-2012, 09:57
Laser-drilled pinholes are fine, but it's not difficult to make a good, round pinhole. You can buy a lot of thin brass sheeting for the cost of one laser pinhole. It does take some practice, but there are good resources on-line on how to drill a pinhole yourself. I found it helpful to have a transparent printer's gauge that I could put on the end of a loupe to measure the diameter of the pinhole. You can estimate pretty accurately from there.

Yes, the 3.5X focal length is a rule of thumb. A 120mm focal length pinhole will cover 8x10". The central 5 inches of the image are much sharper than the outer portions, and there is a little light falloff toward the edges, but it's not extreme.

See Eric Renner's website at http://www.pinholeresource.com for laser pinholes, lens cap pinholes, and pinhole cameras.

Peter Gomena

pbryld
4-May-2012, 11:10
You are describing an image I can only desire, Gomena :)

Kurtdriver, those look interested too. If one wanted to do pinholes on a real camera, I think they would be nice to have quality-feel-wise.






What a need site, that mrpinhole! Thanks!

Whoops, meant 'neat' obviously.

JoeV
8-May-2012, 07:43
The thickness of the pinhole material has some effect on light falloff.

A theoretical pinhole of zero thickness will have light falloff as per the cosine^4 function, due to the effects of increased distance to the pinhole, and because the aperture is being viewed increasingly as an ellipse away from the central axis.

Now add the thickness of the pinhole material into the equation and you can see the pinhole is really a shallow tunnel; if the tunnel is deep enough (i.e. the material is too thick), the off-axis view of the pinhole as being an ellipse becomes truncated by the walls of the tunnel, further reducing light throughput, leading to some vignetting in the corners, perhaps, if the material is of sufficient thickness.

EDIT TO ADD:
The relationship between focal length and film size is helpful in determining the camera's angle of view. Generally, if the focal length is around the size of the film's diagonal width, it will have a "normal" angle of view, and exposures will be more even across the image between center and corners. As you increasingly shorten the focal length in relationship to the film size, more light falloff and vignetting occur.

Imagine an infinite pinhole camera, one where the film plane extends outward in all directions. Whatever distance you place between the pinhole and this infinite film plane, the image circle formed will gradually fade away to black as you get further in angle away from the centerline of the system. Now crop this infinite film plane down to some finite size and you can see that your choice of focal length together with film size determines how much off-axis light falloff.

Regarding camera design, I've taken to building box cameras out of black foam core board and black gaffers's tape (not black duct tape but the real gaffer's tape), small enough to fit within a changing bag. The camera has a lid that slides off when inside the changing bag, where inside the camera, behind the film plane, is a storage compartment for many dozens of sheets of paper, enough for a vacation's worth, if needed. The camera is reloaded, out in the field, between shots.

For an ULF version of this idea (like 11x14), you'd have to employ either a changing tent (the kind used for reloading LF film holders), or build arm sleeves into your box camera to permit the paper to be directly reloaded while out and about.

Sheet film holders, while a great convenience for cycling through many shots, can be fairly easy to carry in the 4x5 size, but a stack of even four 8x10 holders can weigh as much or more than an 8x10 foam core box camera in its entirety. For 11x14 cameras, carrying sufficient numbers of sheet film holders becomes impractically expensive and cumbersome. If I were spending that much money on such ULF film holders, I'd build a high-quality lens camera system around them instead. For pinhole, keep it simple and inexpensive. My "storage slot" box camera concept, reloaded inside a changing bag, is a practical and inexpensive compromise.

-Joe