Topic: Building a 4x5

[ChristopherCoy]

So as not to hijack another thread, I'll start this one.

I've looked at these types of posts for months now, and more than once thought that I would like to undertake a project like this. But I always get confused when it comes to measurements and lens types, so I never ask. But I guess if I don't ask I'll never fully understand...

With the examples below, how do you focus them? I assume because the bodies are rigid they are a fixed focal length? And if so, how do you determine the size of the box to build so that the image is in focus?

I'd really like to try this especially because the actual building of the thing looks like it could be as detailed, or as simple as I want it to be.

I think it's cool to use moulded materials.

But I never tire of reminding folks they could always build their own.   

IMGP4269 by Sandeha Lynch, on Flickr

Very true, building your own isn't that difficult


DIY 4x5/6x12 P+S version 0.4 front by Eirik0304, on Flickr

Having said that, a 65 version would be nice

[Sandeha Lynch]

You have a choice - fixed focus and small aperture, or a helical, with or without a ground glass.  You can build to whatever lens you have that covers your film choice.  I wouldn't mind getting hold of a 65mm, for sure. 

http://www.film-and-darkroom-user.org.uk/forum/showthread.php?t=258

[ChristopherCoy]

So is the lens board 90mm's from the film plane?

[Chalky]

I'm actually (re)building my version of a '4x5 view camera' that uses polaroid film and rollfilm backs. So it's not really 4x5 fil size, but based on those principles. this is version 2 http://www.flickr.com/photos/mattchalkysmith/8525696820/#in/photostream - version 3 will feature removable backs to remove the need for a changing  bag to swop between film and ground glass.

I have now got most of the bits i need heading my way.

The way I understand it is that, for example a 105mm lens will be focussed to infinity when placed at 105mm from the film plane, and will focus closer and closer the more you move the lensboard away from the film plane. Obviosuly you need ground glass for this.

will watch this thread with interest.

anyone got any hints for finding/building bellows? I am using some old polaroid ones currently.

you can also find 4x5 camera plans on interweb if you search a bit... 

the examples above are very impressive :-)

[Francois]

anyone got any hints for finding/building bellows?

Instructables to the rescue
http://www.instructables.com/id/8X10-foldable-pinhole-camera/step3/Making-a-Bellows/

[Sandeha Lynch]

If I remember rightly, the measurement of 90mm is from the film plane to the nodal point of the lens, and that may vary according to the lens design, number of elements, groups, etc. 

So to answer your question about the distance from the lens mount, I can only say approximately 90mm, though probably a bit less.  Adjustment can be done with a thinner lens board or with packing shims.  If you have a ground glass back it's easy to set the lens to what you want.

For home built cams and bellows of all types: http://home.online.no/~gjon/camerabuilders.htm

[Chalky]

Thanks all. Will take a look, looks like some good reading. I'll post as I go. Christopher give it a go. I'm sure you'll knock up something good. Just be careful with the hacksaw!

[Ezzie]

On most large format lenses of a later date, mounted in standard shutters, the flange back distance is stated as being from the rear surface of the shutter. My Fuji SW 90/f8 has a flange back distance of 99.1mm at infinity. As to focusing, mine is mounted on a helicoid. And when it comes to collimation I use the SLR with tele lens method: http://on-your-kitchen-worktop.blogspot.no/2010/10/diy-4x56x12-ps-versions-02-and-03-and.html

[ChristopherCoy]

Thanks all. Will take a look, looks like some good reading. I'll post as I go. Christopher give it a go. I'm sure you'll knock up something good. Just be careful with the hacksaw!

I think I might.


I think I'd like to build something that's more like a point & shoot though, instead of something with all the movements.

[ChristopherCoy]

Instructables to the rescue
http://www.instructables.com/id/8X10-foldable-pinhole-camera/step3/Making-a-Bellows/

ooooooooh that link might have been a bad idea for me.  I've got the itch to build a camera REALLY bad now!

http://www.instructables.com/id/Build-a-120-film-view-camera-with-movements-and-fo/#intro

[ChristopherCoy]

I was just looking at the Fujinon 90mm lenses and they are a bit pricey for my project budget.  Since the Speed Graphics use the 127mm Kodak lenses, and those seem to be plentiful and cheaper, would there be any difference in using one of those?

[Ezzie]

Don't know what your budget is, but I got mine for $170 a couple of years back. It's a stellar lens.

[Sandeha Lynch]

I was just looking at the Fujinon 90mm lenses and they are a bit pricey for my project budget.  Since the Speed Graphics use the 127mm Kodak lenses, and those seem to be plentiful and cheaper, would there be any difference in using one of those?

The difference would presumably be only in resolution.  I think the 127mms, Ektars and the like, were four element lenses, but your Fujinon probably has more and will show a greater sharpness in the corners.  But if you're wanting a p&s that can travel, a smaller, cheaper lens would seem the obvious choice.  The way I see it the main issue about longer focal lengths is that you're having to make a longer box - a lot less compact.  The Schneider 90/6.8 only just covers 4x5 and is a straightforward option since the shutter is quite also small.

[rotarysmp]

Here is a pic of the 4x5 I built.



It is a rough copy of a Tachihara 4x5 built back in 96. At that time I could not source a rack and pinion for the focussing, so it is still focused by sliding the board where the front standard mounts back and forth. While building the 4x5 I became friends with the excellent NZ photographer http://www.mercerphotography.co.nz/about.html Bruce mercer, as he had a Linhof which I measured up to make sure standard film holders, lens bourads and roll film backs could be mounted.

Back then I didn't have money for a lens, so I either used the pinhole, or a 3mm hole in a lens board, with my Rollei T's close up lens pair (Rolleinar) double sided taped on either sides (gave a 160mm f/192 from memory), so I could use the black plastic rolleinar container on the double sided tape as a manual shutter.

Recently, it finally received a real lens, as I picked up a Schneider Symmar 150/5.6 with a scratched rear element cheaply.

The darkroom equipment was sold in 2002 to make way for family, and I have no scanner. "Scanning" 4x5 with an old 8mp DSLR really defeats the purpose of LF.





Looks like I have some light leak issues between back and film holders to work out.

Got distracted with other things lately, and haven't used it in over a year (before that it was a decade between uses, so the trend is positive )

Regards,
Mark

[Francois]

Welcome Mark!

For focusing, you could always use a threaded rod and a nut on the front standard (with the rod running front to back). I've seen some hand made cameras before that used this trick. It's very precise but potentially annoying when you want to move the front standard from one end to the other.

[rotarysmp]

Thanks Francois, for the welcome and the advice.

I decided to wait and do it with a rack and pinion as I milled channels in the wood for that solution back when I did the wood work.  Since I got into Mechatronics about seven years ago, I have had a source for rake and pinion for quite some time (www.maedler.de sells this sort of thing), but the 4x5" just hasn't climbed back to the top of my "projects to actually make progress on" list yet. I am very business remodelling a house which we need to move into soon, and will have plenty to work on for the rest of this year, but would like to tink that I can sort out my machine shop and finish the 4x5 sometime next year.