Another 4x5 pinhole

BetterSense · Jun 23, 2009

I didn't have any of them fancy film holders, so this one follows the design of my 8x10...the film sits in the back, and the front slides into the back holding the film flat. Reloading is by changing bag, but it should be a lot more convenient with the small size! It's really quite cute.

I stole CuS's idea of using a shutter out of an old camera. I stole the shutter assembly out of my Jiffy Kodak 620 camera, which has a "T" setting. I just don't know if the shutter blade seals well enough around the pinhole, since you can see an air gap when it is shut. I made my first exposure on the way to work this morning, but I don't know if it's going to work. I made the pinhole pretty small, it's about .35 mm and the focal length is like 60mm

Apologies for the quality of the image, it was the only one I had at work since it was attached to an email to my friend.

bsdunek · Jun 23, 2009

If I'm calculating correctly, that's f 171 - not small at all. My home made pinhole for my Mamiya Press comes out to f 207, and the photos aren't very sharp. I'm going to make a new one somewhere between f 250 and f 300.
That said, try yours before you change anything - it may work fine.

CuS · Jun 23, 2009

0.35mm pinhole would need about a 77mm focal length - roughly - try it and see.

I have my 0.3mm pinhole at 50mm but it should be a 57mm instead - i will try that tonight - here are some shots with "Ned", btw (not sure if I shared these yet):

Dead Link Removed

Cant wait to see your stuff!

I guess the smaller the pinhole (to a point), the sharper the image.

I wonder what the best size is?

BetterSense · Jun 23, 2009

Well it sure seemed small compared to the .5mm in my 8x10. I had a hard time making one small enough with my typical sewing needles. I heard that acupuncture needles were better but I don't know where to get any.

BetterSense · Jun 23, 2009

Awesome; I just came home and developed my two shots. I forgot to mark which was which, though. They were shots of a building and I did one at about 9am for 15 seconds, and then did another one about 11:30am for 5s. They both look similar but one is slightly more dense and contrastier. I have some light leakage around the edges which I think I can fix with felt. I used Arista EDU ultra 200 and developed in D76 1+1 for about 6 minutes

CuS · Jun 23, 2009

post dem images - i wanna see!

BetterSense · Jun 23, 2009

Well I left them hanging up to dry. I developed them during lunch.

I don't have a LF scanner so I will have to make contact prints and scan those tonight

BetterSense · Jun 23, 2009

http://i109.photobucket.com/albums/n78/daravon/pinholenserl.jpg

It works, but I'll have to approach it more seriously. Right now it doesn't seem like it's as sharp as my big camera.

DWThomas · Jun 23, 2009

Looking good. APUG should have a big turnout for WPPD 2010!

DaveT

CuS · Jun 23, 2009

looks good - and at least you have a nice subject

BetterSense said:
http://i109.photobucket.com/albums/n78/daravon/pinholenserl.jpg

It works, but I'll have to approach it more seriously. Right now it doesn't seem like it's as sharp as my big camera.

Mine are a bit blurry too - maybe a mismatch b/t pinhole size and focal length? Since its hard to make a pinhole for a set camera, maybe make a good pinhole and build the camera around it - or buy one of those fancy-dancy laser-cut pinholes - whats the fun in that though?

BetterSense · Jun 23, 2009

I would buy a laser-cut one if it wasn't so expensive.

I still think a chemically-etched pinhole would be the best, because then the edges would taper down to a perfect edge. I'm trying to figure out how I can make one at work.

I kept noticing when I was scanning my pinholes to measure them, that there was often burrs or other jagged edges on them. Maybe I'll make a bunch of pinholes in a piece of can, then look at them in the microscope at work, and pick out the best-looking one.

bobwysiwyg · Jun 23, 2009

I've never owned/used a pinhole cam. but it does interest me. I follow the related threads quite a bit. What do you experienced folks think of this?

http://cgi.ebay.com/Skink-Laser-cut-pinhole-for-Macro-%2F-Micro-photo-0.1mm-_W0QQitemZ380128652485QQcmdZViewItemQQimsxZ20090603?IMSfp=TL090603179004r24511

BetterSense · Jun 24, 2009

I think they look really cool, and I would like to have precision pinholes, but at $30, it's too ironic for me. Plus, I have seen people selling complete assortments of laser-cut pinholes for that much money, and not just one size.

CuS · Jun 24, 2009

I know what you mean - jagged edging

BetterSense said:
I kept noticing when I was scanning my pinholes to measure them, that there was often burrs or other jagged edges on them.

I have th same issue - mine are often very jagged and burred under scanning. An idea mught be to mount a sewing machine needle in a drill press and drill the pinhole at high speed - this might plasticize the metal at the edges of the hole and reduce burring.

Etching would be teh best though - the lands would be sloped.

DLawson · Jun 26, 2009

bobwysiwyg said:
I've never owned/used a pinhole cam. but it does interest me. I follow the related threads quite a bit. What do you experienced folks think of this?

http://cgi.ebay.com/Skink-Laser-cut-pinhole-for-Macro-%2F-Micro-photo-0.1mm-_W0QQitemZ380128652485QQcmdZViewItemQQimsxZ20090603?IMSfp=TL090603179004r24511

They're a couple bucks cheaper here:
http://www.lenoxlaser.com/pinholephotography/pinhole_photography_laser_drilled_lenses.html

If I read the forms correctly, shipping is about half the eBay item's.

(Haven't used Lenox, just bookmarked the site.)

DWThomas · Jun 26, 2009

Hmm - those Skink "pancakes" are quite elegant. A Canon FD model would look nice on my A-1, wish they made one for Bronica SQ family! But by the time you get a pinhole, you're talking $60 with shipping. The Lenox looks like a less expensive way to find out how much better a laser drilled hole is, and I like the fact that they have closer size intervals. From 0.7 to 0.8 mm isn't such a big jump, but from 0.2 to 0.3 certainly is.

Enh, maybe before next April I'll get something to try.

Thanks for the links.

DaveT

Another 4x5 pinhole

Privacy & Transparency

Privacy & Transparency