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Barry Kirsten
5-Feb-2017, 22:39
Hoping to get some interest in this aspect of photography, and following the demise of that excellent site f295, I thought Iíd set the ball rolling by describing in more detail how I went about building a camera which I recently mentioned here: http://www.largeformatphotography.info/forum/showthread.php?36782-Show-off-your-Large-Format-camera!/page324

A friend on this forum happened to throw in a box of 5x12 x-ray film in a parts swap we did and that got me thinking about a panoramic pinhole camera in this format. The result here followed months of trial and error:

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The camera has front rise and fall of +/- 15mm to allow it to be used level and yet ensuring that the horizon remains straight, since the horizon will be curved in a curved film-plane camera if it is tilted up or down. As it turned out I could only find 15mm as Iíd made the frame for the front too wide top and bottom. I havenít yet tested whether this is enough. The camera has a bubble level in the top and sighting dots made from 1Ē painted nails to aid composition.

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The first hurdle to overcome was bending the plywood back. This was eventually achieved by scoring the inside surface with vertical Vs spaced at 1cm intervals using a router, then soaking and careful progressive bending over several days, using clamps and weights, then eventually gluing top and bottom to hold it all together. It was a hair-raising experience and I felt several times that I came very close to splitting the wood. In retrospect, Vs at 5mm spacing may have made the bending easier.

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I used a 0.5mm EMS (electron microscope) aperture for the pinhole. These are truly excellent - laser drilled precision. Iíve used them before on other cameras with great success. Iíd never think of making my own now. Theyíre available from a guy on f295 at $1 apiece posted. If anyone has contact with Earl, would you mind seeing if heís interested in posting here?

Mounting these pinholes is tricky, since theyíre very small. Some folk use tape with a 1.5mm hole punched in it to grab the pinhole; the pinhole is then taped to the camera front. I donít yet have a punch to allow me to do it this way, but Iíve ordered a couple from China. Meantime I mount my pinholes in a small brass washer, using a couple of blobs of black paint that find their way by capillary action. The pinhole on its washer is then mounted into a recess drilled into the plate (more black paint).

As per my previous post (above) I found vignetting on my first test shot, which I immediately thought was an image circle issue. I thought that I may have to mount the pinhole further forward to fix this. However a member (NedL) was right when he suggested that it was obstruction. Sure enough, although Iíd beveled the exit hole in the rear of the plate, there was still a definite ridge, which Iím sure was responsible. Iíve since ground this down, but have not yet tested it as I have a scratching issue with my developing trays and have to get some glass cut to remedy this. The next pic shows the rear of the plate and also a view of the front showing the clearance needed for rise/fall and horizontal field.

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The 0.5mm pinhole is mounted 135mm from the film plane. I had intended it to be 127mm (5Ē), the radius of the film curve, but things donít always turn out as hoped. Fortunately pinhole is very forgiving, and I donít think any unevenness in exposure will show up. At 135mm the speed is f/270. The one test Iíve done suggests that the image is a little soft. Iíll do a few more tests after I sort out my developing issues, and may yet go down to 0.4mm and f/340.

A note on bits and pieces: I now get everything from China via eBay. No doubt about it. Over the years Iíve scoured the country from engineering suppliers to model shops and found sourcing small screws and knobs etc, the type of things so vital to DIY photography, next to impossible. For me eBay is the answer, and knowing how to search is very helpful. Terms like M3 screws for 3mm metric, or knurled knobs, case clips etc usually turn up direct hits or lead to further search clues. The two brass pieces in the last two pics are known in eBay speak as "M3 / M4 Brass Knurled Nuts Insert Embedded Nuts"; I used these as nuts to secure the front panel and as embedded nuts held with epoxy for the front panel to bolt into.

So how about it LF Pinholers? I'm sure there would be much interest in your own pinhole camera building achievements. There is certainly interest in pinhole photography here, as evidenced by the many favourable responses to pinhole images posted here. Love to hear from you.

Randy
6-Feb-2017, 16:24
Barry, that is quite a bit of workmanship. Thanks for the detailed description. I am afraid the extent of my pinhole camera construction is making a lens-board pinhole for my 8X10, 5X7, and 4X5 cameras.

DHodson
7-Feb-2017, 00:23
Hi Barry

Good idea and thanks for taking the initiative. I'm just starting to explore pinholes so this will help me a lot. Congratulations on your camera by the way - very nice.

Regards
Dave

Graham Patterson
7-Feb-2017, 10:05
The quality of so many of these home built projects puts me to shame. I think I linked to my cigar box camera before, but the details are here: http://grahamp.dotinthelandscape.org/pinhole.html
Much cruder in construction, though I have done some decent work with it: http://grahamp.dotinthelandscape.org/pinholeday.html.

Barry Kirsten
7-Feb-2017, 13:21
Thanks Dave, and good luck with your adventures into pinhole. Thank you too, Graham. I must say I'm impressed with your website, both pinhole images and your ventures into camera making, both pinhole and the 8x10.

My camera has a way to go yet. Another test shot yesterday still shows vignetting which has resisted my previous attempt to fix it. I think the problem is the thickness of the pinhole mounting plate. I used 2mm aluminium because I didn't have 1mm on hand, and I think the pinhole needs to be further back into the plate. As NedL said previously, vignetting can be hard to fix with a curved film plane.

Barry Kirsten
7-Feb-2017, 18:36
Yesterday's test. Vignetting cropped out, very minimal work in LR. A bit too close to the subject; I'll have to get used to vertical composition - horizontal is no problem as I have sighting dots on the camera top. I'm pleased that scratching is no longer a problem, thanks to glass in each tray.

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Graham Patterson
7-Feb-2017, 21:58
I find a masked bright light in front of the pinhole and a dim room makes it easier to work out if there is anything in the path to the film corners. My problems are either pinhole thickness or extreme angle effects, since I work with flat film. It sounds like you have more subtle issues.

NedL
7-Feb-2017, 23:39
I always check with the sun, but they're always simple boxes or cans and easy to look inside with the top off. Thanks very much for starting this thread, I'm looking forward to reading it!

Compared to other beautiful cameras ( Like the amazing creations of Steve Irvine! ), mine are all made from mat board or foamcore or tin cans, although they have the advantage of being easily recyclable. My latest was from last WPPD (http://www.ipernity.com/doc/295785/41394268).

Randy
8-Feb-2017, 11:04
Seeing these examples with the curved film planes has me considering fabricating a camera in preparation for WWPD (my attempt last year went kablooey because I didn't notice that the sun was shining on my pinhole). I would most likely go for the simple materials like Ned's camera, and would probably make it to use 4X10 film (cut down 8X10 X-ray film). I am guessing the idea is to have the pinhole - to - film distance about equal from end to center to end, thereby keeping the exposure consistent the length of the film?

Since the film plane will be curved, what are the thoughts on curving the pinhole so that it matches the film curvature? Is that something that has been tried? I have never explored that idea so I don't know if there would be any benefit.

DHodson
8-Feb-2017, 11:06
Just wondering if someone could point me to a good starter book on pinholes.

Thanks
Dave

Barry Kirsten
8-Feb-2017, 13:28
Hi all, I don't try and make these cameras out of a sense of elegance, but because I like woodwork and also stability and ruggedness. A great justification for the latter was the other day when I'd just made the second test photo... I was coming down from the rocky area when I slipped and fell on my left side, on top of the camera I'd just used. Fortunately it was not damaged!

Dave, there is a book by Renner referenced in this excellent article by Brian Young here: http://www.alternativephotography.com/pinhole-design-what-lord-rayleigh-really-said/ I haven't read it, but it, but it might be helpful. I find the web a great place for finding pinhole info.

Hendrik, you may find this article helpful also. In general for close up work you need a small pinhole because each diameter of pinhole has a limit for close focus at a given film-pinhole distance. There are no hard and fast rules, so you might like to start experimenting with a pinhole of 0.2mm at a lens-pinhole distance depending on your camera. This should provide very close focus. For pinhole supplies there is Lennox Laser, https://lenoxlaser.com/ Also a man named Earl who used to be on f295, but I don't have contact details for him at present. He sold laser drilled electron microscope apertures which are just perfect for pinhole. James at http://www.aupremierplan.fr/ sells Earl's apertures already mounted.

NedL
8-Feb-2017, 23:15
If you are interested in the math behind macro pinholes you can find the Prober-Wellman formula here (http://www.huecandela.com/hue-x/pin-pdf/Prober-%20Wellman.pdf). The "optimum" does not fall off all that fast as you get closer to the camera, for example if you make one to be optimum at 2 inches, it will work pretty well at 1 inch. Strong diffraction effects will be obvious in more more distant subjects, but can be interesting. The image looks different depending on whether the aperture is too big ( geometric blurriness ) or too small ( diffraction ).

JoeV
15-Feb-2017, 10:05
Just wondering if someone could point me to a good starter book on pinholes.

Thanks
Dave

Dave,

Eric Renner's book is considered a modern classic on the subject. He's recently updated the book, here's an Amazon link:

https://www.amazon.com/Pinhole-Photography-Technique-Application-Alternative/dp/0240810473/ref=dp_ob_title_bk

~Joe

PS: I see that Barry has linked the same book above.

DHodson
15-Feb-2017, 18:22
Thanks for the link to Eric Renner's book. I checked Amazon here in Canada and they want $62 (Canadian) for it so hopefully I can find a used copy somewhere.

Dave

Dan Fromm
15-Feb-2017, 19:53
Here: http://www.alibris.com/Pinhole-Photography-Eric-Renner/book/7942802?matches=28

DHodson
15-Feb-2017, 20:51
Thanks Dan - that's a new link for me

blindpig
24-Feb-2017, 08:07
Well Barry,"GOOD ON YOU"! Think this is a great idea and hope it takes off.
Your camera is beautiful, a piece to be proud of for sure and looks like a good picture maker.You'll work out the vignetting issue,just a small bump in the road for ya.
Guess you can access"Amazon" down under,I've found many parts for my builds there(and often free shipping)which helps a lot.
Keep up the good work and please share as you go.
Don

Barry Kirsten
24-Feb-2017, 13:13
Thanks for the kind words Don. Actually I've just identified the cause of the vignetting, it's the filter ring, as Shane Booth suggested. Thinking the vignetting was caused by a ridge behind the pinhole, I ground away part of the mounting plate (with the pinhole removed) but it didn't work. Sighting along my alignment dots on the top of the camera, with the pinhole directly below the centre dot on the top, shows the edge of the filter ring directly in line. The solution is a larger filter ring. I found I can just sneak a 58mm ring in there and still be able to adjust the rise and fall. I hope it doesn't vignette with a filter mounted. Wait and see for next installment. Thanks for the tip about Amazon, I'll look into it. There is talk that Amazon may open in Australia, but we'll have to wait and see. Best wishes Don.

Barry Kirsten
10-Mar-2017, 22:17
At last the modification. I made a new front panel out of 1mm aluminium and increased the filter ring to 67mm, which makes sense since I have standardised on 49 and 67mm filters and don't have any 58s. No sign of vignetting. This is a very wide camera (about 110 degrees). At the right end you can see blurring, which is actually my head. About 10 sec. into the exposure I realised I might be too close and moved away - sure enough that was the case. I also reduced the pinhole to 0.4mm and that slows the speed to f/340 but improves sharpness, I think. This morning's test shot, done at sunrise was on Kodak dental panorama x-ray film (double sided, green sensitive). Film was rated at ISO 100, exposure was 30sec. and development was in PMK 1+2+100 for 8min. I'm now developing on glass in the bottom of the trays, but am still getting scratches due to handling during loading and unloading, so I'm learning just how careful I have to be with this film. Film photographed on light box with digital P&S, no modification to image other than inverting.

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Jim Jones
11-Mar-2017, 09:32
Consider that Joe's link is for the 2009 edition while Dan's is for the 1999 edition which should contain most of the same information. My 1995 edition has more information than I'll ever absorb.

NedL
11-Mar-2017, 11:07
That's great Barry! 110 degrees sounds about right --- get close, then closer!

blindpig
11-Mar-2017, 17:50
New you'd get it straightened out Barry.Looks like a good test shot(you might stand still a little longer so we could get a better look at ya)LOL!
Good job all round...
Don

Barry Kirsten
11-Mar-2017, 22:24
Thanks Ned and Don. Another reason I reduced the pinhole size down to 0.4mm is to allow closer focus. I figured that the 0.5mm would not focus under about 1.5m, whereas the 0.4 should be OK to about 10".

Don, I'm thinking about pinhole portraiture, perhaps a 4x5 dedicated portrait camera and higher speed film. The idea of a selfie of my old mug is not a pretty thought.:rolleyes: That job is at the end of a long queue at the moment.

Cheers to both of you.

SMBooth
14-Mar-2017, 22:58
Great to see you got the vignetting sorted out.
As for references, don't forget the "Mr Pinhole site" http://www.mrpinhole.com and the wonderful Pinhole designer program (windows only) http://www.pinhole.cz/en/pinholedesigner/ and for some inspiration - http://fslashd.com

Personal Ive just finished a 11x14 camera which is adjustable from 210mm to 300 mm.

Barry Kirsten
15-Mar-2017, 00:15
Thanks for those references, Shane. I'd forgotten the f/D site... Keir actually used one of my images in 2015, but I can't post it here because it's 2x3. But a great inspirational site. The 11x14 camera sounds interesting. Do you plan to use it for film or paper (or both), and are you using interchangeable pinholes?