LF pinholes?

[walter23]

How do you manufacture a nice pinhole for 4x5 or 8x10? How is desired focal length accounted for (I know a pinhole doesn't have a focal length per se, but I've heard there's an optimum diameter for a given focal length).

I'd like it to give a well defined image with only a little bit of that pinhole softness. It should have full 4x5 coverage & ultra wide angle. After losing out on a 65mm on ebay ($500 was my max, wishful thinking I might add) I've figured the only way to reasonably afford to go very wide on my LF is to make a pinhole.

Any tips would be great. I've looked at some of the pinhole resources but they don't usually give a simple straightforward answer to these things nor indicate how to get reasonably detailed ('sharp') images.

I'd almost buy a nice laser-drilled precise plate if needed. Where would I get one suitable for LF?

 

[Pinholemaster]

http://www.pinholeresource.com/

 

[Jim Noel]

I believe Calumet still lists a set of 4 or 5 laser drilled pinholes for around $20-25.

 

[walter23]

I believe Calumet still lists a set of 4 or 5 laser drilled pinholes for around $20-25.

Do you know if there are any requirements (with regards to, for example, the thickness of the material it's drilled in) to ensure coverage for 4x5 or 8x10?

 

[k_jupiter]

Walter,

there is a whole forum on pinhole cameras on Apug.

Read it.

tim in san jose

 

[walter23]

Thanks tim.

 

[Murray@uptowngallery]

f295.org also

 

[Stephen Frizza]

A client of mine has a 20x24" pinhole camera they built themselves out of a car boot hehehehehe.

 

[Murray@uptowngallery]

Sounds like you have a bellows, so you make a pinhole in accordance with any of the best practices (I don't believe the laser ones are any better in practice compared to well made hand-done ones).

You can measure it by scanning it at high res and viewing on screen, then scaling the scan resolution to the monitor resolution (SVGA is 96 dpi, not 72 as people keep saying - that was plain VGA decades ago).

Then, regardless of what your odd size pinhole ends up being, you can set the bellows accordingly.

Ask in the Pinhole forum here or f295 and the list of nuisance-like steps will become quite manageable.
Or buy one as you said. There is also someone selling sets of apertures in 0.001" stainless steel for $30 on eBay.

One person told me they were laser-drilled, but I only saw the words 'micro-drilled', which is not the same, to me.

Hand-bored ones can have a knife edge, resulting in thinner apertures. I have seen some laser-drilled ones that had 'slag' around the hole, making it far thicker than intended.

I'm not sure why roundness is claimed to be so important, as a square hole works too. The math model for diffraction is different for a square or slit vs a round aperture, but so what?

The nice thing about the bellows cam is you can alter the distance and recalculate the exposure far easier than making holes exactly the size you thought you needed.

 

[John Bartley]

Lee Valley tools sells numbered drill bits in a set (quite cheap) that go as small as about 0.020" (iirc). When I made my 4x5 pinhole camera, I just put a bit of brass shimstock between two pieces of thin wood, clamped tight and drilled thru'. It gave a nice clean hole in the brass and gave a fairly nice picture.

cheers eh?

 

[Murray@uptowngallery]

I find that one has to select subject matter that is compatible with pinhole. Same with zone plates.

Pinhole has strengths and weaknesses compared to lenses. Too often I got results that looked like conventional photos that were disappointingly blurry. Yet with certain subjects, people respond enthusiastically to the blur. (In general, on pinhole forums (fora?), not necessarily to my images :O(

I found that relatively large subjects at close distances are very compatible with pinhole's DOF strength. I was always unhappy with small-detailed subjects at infinity. I do not have zone plate figured out. I have several but don't 'get' alot of the ZP images many people respond favorably to.

I think wide to very wide angle is my favorite look with pinhole. Normal angle of view pinhole (converted cameras at same spacing as lens) for my experience has resulted in too many images that looked like poorly done lens work. :O(

With wide angle you will probably find that, in accordance with the advice/adage we Pinheads dispense, you just can't get close enough. If you think you are close enough, get closer first.

Using converted cameras viewfinders on wide angle shots, as a rule of thumb I compose in the viewfinder, then cut my distance to subject in half. I haven't pushed that any further because of eyeglasses & parallax.

 

[walter23]

Thanks Murray.

I find that a lot of pinhole stuff is indeed just a crappy shot that's been taken with a pinhole and branded "interesting" as a consequence of the novelty. Just like any kitchy effect - IR being one of the more obvious ones, but also cyanotype, pt/pd, HDR digital, lith printing, etc. Of course a lot of images are explorations of technique and we all take our lion's share of shitty shots

On the other hand I've seen some really stunning stuff done with pinholes, as you've mentioned incredibly close stuff where you can take advantage of the DOF offerings (there are things you can do with pinhole that no macro camera could ever do), but also anything that relies on an impression and is well composed, illuminated in the right kind of way, and suited to the pinhole look.

I have some ideas on that latter front, but only time will tell if these ideas will materialize into anything worth displaying.

BTW I ended up buying a set of pinholes from pinholeedun.com as well as a set of "EMS 0.4mm pinholes" from a guy offernig them on f295.org's forum (actually he's giving them away to anybody who donates $5 to the operation of the forum).