4x5 Homemade Pinhole - I finally made one!

[CuS]

Well, I went and did it. I cobbled together a nice box (with a 50mm focal length) from black foamcore and black matte board.

I had an old lens/shutter assembly from an Agfa Viking 4.5 from which I removed the front and rear lens elements. I then made a pinhole from a diet coke can, cut it to fit in the front lens-element holder assembly and screwed it into the back of the shutter assembly.

After I made the pinhole, I scanned it and it measured ~0.3 mm (almost the perfect size for a 50mm focal length - I got lucky).

I mounted the shutter in the front of the box and rigged some elastic to hold the film holder against the back.

I just shot two sheets of tmax400 and i'll dev them tonight.

I'll also take some pics of the camera and scan the film and post for all to see.

Sorry for the rambling post, but I was really excited to share.

 

[bobwysiwyg]

Look forward to the pics and pics of the camera.

 

[DWThomas]

Sounds cool -- looking forward to seeing the results.

DaveT

 

[Greg Heath]

Great JOB ! I built one in March... and it works great. I picked up some of the 100speed (50 count) 4x5 Ultra EDu...film ... from Freestyle photo for $20...and it's been a blast ever since.

Post some pics when you get them done...

Congrats.

Greg

 

[CuS]

Here they are - as promised

I'll also take some pics of the camera and scan the film and post for all to see.

Well, here they are - let me know what you think. The film is currently in the photoflo - i'll get them up tomorrow.


Here's a link to my flickr page where you can see more of a description of the camera and materials.

Dead Link Removed

 

[BetterSense]

I was wondering, where do you get your film holders? I want to build a 4x5 pinhole camera and it would be neat if it used film holders, but I don't have any.

 

[bobwysiwyg]

I was wondering, where do you get your film holders? I want to build a 4x5 pinhole camera and it would be neat if it used film holders, but I don't have any.

Try eBay. They're out there all the time.

 

[Andrew Moxom]

Great camera... Must nice and lightweight too

 

[DWThomas]

Good job! The camera looks well thought out.

My past pinhole efforts have been centered around Worldwide Pinhole Photography Day in April each year. So far, I've gone high tech, using a regular camera with a special lensboard or body cap for good solid film handling. But having done that a few times now, I was already thinking of building an "engineered" design from from scratch, as you've done nicely here. Or maybe even going really low tech -- back to the traditional cans, cookie tins or whatever. I have liked the ability to go out on the road and take multiple shots without a darkroom or changing bag, but I suppose I don't need to do a "road trip" every year.

Now and then it's a fun change from using novelties like lenses.

Keep up the good work!

DaveT

 

[Paul Cocklin]

Just curious, how would one calculate coverage of image circle? I've been thinking of doing a 4x5 pinhole camera myself, (and will, eventually) and was wondering how far back the holder needs to be to ensure full coverage. Also, I know that it's said that these types of cameras have infinite dof, (or lack thereof) but is there an actual hyperfocal distance?

 

[Paul Cocklin]

oh, pics look really good, too. Very cool looking camera.

 

[SMBooth]

Just curious, how would one calculate coverage of image circle? I've been thinking of doing a 4x5 pinhole camera myself, (and will, eventually) and was wondering how far back the holder needs to be to ensure full coverage. Also, I know that it's said that these types of cameras have infinite dof, (or lack thereof) but is there an actual hyperfocal distance?

Try this link http://www.mrpinhole.com/index.php

 

[DWThomas]

Well, in the Windoze environment, there is Pinhole Designer which has all sorts of handy calculations. I think in theory the field of view approaches 180º, but the light falls off and, as seen in CuS' photo on Flickr, the ultimate coverage can wind up being limited by the mechanics surrounding the pinhole. My first body cap adapter for the Bronica suffered serious vignetting, after which I did what I should have done in the first place and plotted a scale drawing of all the parts and spacings to work out larger holes for some of the components. Rev 2 was way better, even though the pinhole and the pinhole-to-film spacing didn't change. As a practical design, I would guess a 90º angle of view (film to pinhole distance approximately equal half the diagonal of the film frame) should be easily possible, and maybe out to 120º or so. But it can get tricky, as even the thickness of a foamcore or plywood mounting board could cause vignetting at some point.

I believe a knife-edge pinhole is needed for very wide angles too, or at least a very thin foil. Otherwise the light fall-off will be more severe.

The next step is then to work out an optimum pinhole diameter for the given spacing. Using a press camera was cool because the film-to-pinhole distance could be varied over a large range with one pinhole installed.

I wouldn't say there's a hyperfocal distance, but there is an interesting phenomenon observed by several of us last year. As you look further into the background, there seems to be softer focus. This is apparently caused by resolution required to render the detail reaching a point where it is greater than the pinhole can render, not really a focus issue.

DaveT

 

[Paul Cocklin]

Thanks to both of you for the info. I appreciate the details, Dave. Sorry to the OP for taking a detour with his thread.

 

[AlternativePhotograp]

Hi Paul, and everyone else.
The image circle is roughly 3,5 times the focal length. There is a book i have just co-written which covers the basics of pinholing, this and a lot more. It's called "From pinhole to print - in less than an hour" More info here:
http://www.alternativephotography.com/books/pinhole_to_print.html
Good luck!

 

[CuS]

Just curious, how would one calculate coverage of image circle? I've been thinking of doing a 4x5 pinhole camera myself, (and will, eventually) and was wondering how far back the holder needs to be to ensure full coverage. Also, I know that it's said that these types of cameras have infinite dof, (or lack thereof) but is there an actual hyperfocal distance?

I was using this formula which related pinhole diameter to focal length:

d=(sqrt(f))/25

where:
d= pinhole diameter
f=focal length