Fixed focus camera?

[Dave Dawson]

In a moment of madness I'm thinking of building a 5x4 fixed focus camera with a spare 90mm f8 Super Angulon shoved on the front and an International back on the back of what would basically be a wooden box, the depth of which would give be set to focus at infinity.

Anyone else done it?

Cheers Dave

[PAUL O]

Sounds similar to the Hobo Point and Shoot? These were wooden frames in a number of formats up to 10x8 and all models utilised a wide lens. These were designed so that the lens was set at infinity focus and they had a clip-in plexiglass screen for composition - with a small "viewfinder" on the top plate - I think this was in fact a door spy-hole fixture.

Try a Google search? They were popular in the US about 8 years ago and used to be sold/manufactured by Bostick & Sullivan (I think!).

[Alan Clark]

Dave,
It's a great idea. I made one myself a couple of years ago using a 90 mm Super Angulon. Mine doesn't focus at infinity. It focusses at the hypofocal distance for f45-about 8 feet. So everything from infinity to 4 feet is sharp.
I didn't build a removeable back into my camera. The film holder fits into the camera body. To get a vertical picture I rotate the whole camera through 90 degrees. The whole thing is very light and very easy to carry around.
I can supply more details if you wish.

Alan

[Dave Dawson]

Hi Alan, possibly the whole group would benefit from more details, photos, plans etc.

Thanks Dave

Dave,
It's a great idea. I made one myself a couple of years ago using a 90 mm Super Angulon. Mine doesn't focus at infinity. It focusses at the hypofocal distance for f45-about 8 feet. So everything from infinity to 4 feet is sharp.
I didn't build a removeable back into my camera. The film holder fits into the camera body. To get a vertical picture I rotate the whole camera through 90 degrees. The whole thing is very light and very easy to carry around.
I can supply more details if you wish.

Alan

[Alan Clark]

Dave,
I will be pleased to post some photographs if someone can tell me how to do it!

Coincidentally I am in the process of building a 10 x 8 fixed focus camera based on an old 121mm Super Angulon. I can pst some pictures of this as well.

The important measurement is the distance from the back of the lens panel to the interface between the camera back and the film holder.
If you have a regular 5 x 4 camera, put the 90mm lens on it, stop down to f45, and focus on infinity. Then slowly extend the bellows and stop when you are just on the point of infinity going out of focus. Then remove the lens and make the above measurement as accurately as you can. You now have the front to back measurement for the box. This is the only critical bit. Making the box is quite straightforeward.

Alan

[Joanna Carter]

I will be pleased to post some photographs if someone can tell me how to do it!

If you have your own web space, then you can upload the files there and simply place a link to them in a message by using the "img" tags that you see at the top of the message editing box.

If you do not have your own web space, then you can now add attachments to a message; there is a tab under the message editing box that is entitled "Upload attachment" but you must keep the image as small as is practical; around 700pixels on the longest side is a good guide.

[Dave Dawson]

It will take a more computer literate person than I to tell you how to plonk photos on here (I suppose that is sad really). I would use nearer f22 than f45 so may make the focus point a little further away than 8'. I appreciate that as long as the box is 'true' then the only critical thing is the lens to focal plain distance.

Cheers Dave

[Steve Smith]

I had similar plans for a 65mm Super Angulon I have as I didn't want to pay £240 for a focusing mount. However, after a bit of playing around, I found that I could modify a broken Olympus 50mm lens to make a helical focusing mount for it.

I temporarily mounted it to the body of an old 6x6 folder and discovered that even wide open (f8) the pictures look sharp at all distances when focused anywhere from infinity to about six feet.

I am currently building a 6x12 format body for it but I will make the lens mount removable so I can also use it on a simple box holding a 5x4 film holder.

There is a bit about my progress so far here: http://www.freewebs.com/stevesmithphoto/pano612.html


Steve.

[dave_whatever]

I had a similar idea of building a 6x14 rollfilm camera with a 90mm lens but never came to anything. one idea was to hack one of those old kodak 3a autographics but it just seemed a clunky solution. I'd love to follow your lead steve if i ever get the time (and can convince myself i'm handy enough). It always stuck me that the 6x12-6x17 cameras on the market are all priced ridiculously given most of them are essentially just a box with a lens and helicoid - even the shonky chinese ones ain't that cheap.

What i would say to the original poster is it'd be better to make your focus set at infinity rather than some hyperfocal distance. At least then you guarantee a sharp infinty at any aperture and just stop down for the required DOF, rather than being locked into to using f/45 or whatever and still getting a soft horizon. Plus if you build it set to infinity and then later decide you want to focus closer you can shim the lens out a bit with a spacer.

[Alan Clark]

Thanks Joanna, but when I click on "upload attachments" the search button is not active. Where doI have to have my pictures stored in order to add them?

Alan

[Steve Smith]

I had a similar idea of building a 6x14 rollfilm camera with a 90mm lens but never came to anything. one idea was to hack one of those old kodak 3a autographics but it just seemed a clunky solution.

There is a 6x12 format pinhole Holga which seems ideal for this sort of thing. It could even be forced into service as a 6x12 back for a 5x4 camera if attached to a suitably routed out film holder.

http://www.djibnet.com/photo/612/holga- ... 98886.html



Steve.

[dave_whatever]

yeah I've seen those holgas - the nagging doubt I have is that the holga could potentially have crap film flatness (i doubt flatness is high on the agenda of the average holga user) or shonky/breakable film advance mechanism, light leaks etc. hard to know without seeing one though.

[Steve Smith]

yeah I've seen those holgas - the nagging doubt I have is that the holga could potentially have crap film flatness (i doubt flatness is high on the agenda of the average holga user)

I had thought that too but based on my results with the 65mm lens, I don't think film flatness will be an issue!


Steve.

[Joanna Carter]

Thanks Joanna, but when I click on "upload attachments" the search button is not active. Where doI have to have my pictures stored in order to add them?

Hi Alan, I have just checked your permissions and you are allowed to upload files. Any files you want to upload can be anywhere on your computer (just ensure that they are not absolutely massive). Once you can see the Upload Attachments page, you should also see a button with "Choose File" on it (at least, that's what it says when using Safari).

Would you please send me an email or a PM with your phone number and I will talk you through, if necessary.

[Dave Dawson]

Joanna, It's been a VERY long time sinse a woman asked for MY phone number

Alan...I get my measuring stick out today and by my calculations the distance from the film plane to the back of the lens board is about 97mm for a S.A. 90mm f8 lens at infinity........Would you go along with that?

Cheers Dave