Pinhole and Hasselblad body

[Willie Jan]

I bought a Body dop and first made a hole of about .45mm. Images look blurry.
Next I made one with a .3mm hole and they look much better...

I made the hole first with a needle after that finished the hole with a .3mm drill and after that polished it with sandpaper to remove any edges. There are lasercut pinhole for sale on ebay, but would they increase quality that much?

 

[Sirius Glass]

See

http://pinhole.stanford.edu/pinholemath.htm
Dead Link Removed
http://www.pinhole.cz/en/pinholecameras/pinhole_01.html​

to determine the proper pin hole size.

http://www.pinhole.cz/en/pinholecameras/exposure_01.html​

to determine the proper pin hole exposure.



Steve

 

[Jim Jones]

I second Steve's suggestion of http://www.pinhole.cz/en/pinholedesigner/]. A user constant of about 1.4 or 1.5 provides maximim central sharpness. http://www.f295.org/ is another source with much information on pinhole photography.

 

[Brett_Jurgens]

After determining the proper needle size, I hold the needle and spin the shim stock around it, then finish with sandpaper. Look at it under a strong loupe and back lit to verify no burs and roundness. With the correct size, it will be very sharp. I have never tried it, but have heard of people using arcing electricity to burn a pinhole in to the shim stock. Not sure how you would control the size, but it sounded interesting.

 

[DWThomas]

I use the dimple and sand method wherein you don't necessarily pierce the shimstock with the needle, but raise a "pimple" and sand it using fine (400 or 600 grit), wet-or-dry sand paper. I sand wet with a gentle circular motion. I think my most recent pinhole, made for WPPD last April, was my best yet. It may have been helped by using 1 mil brass shimstock instead of my usual 2 mil. The thinner stuff is a bit harder to keep flat and not damage it, but since the ideal pinhole has a knife edge, the thin stock gets closer to the ideal automatically. Roundness, and an absolute minimum of edge upsets - tears, etc. is necessary for really good results. This year's pinhole camera was a 4x5, it does seem that larger formats produce sharper images.

I used a .014 inch (0.36 mm) pinhole for a body cap adapter for my Bronica SQ-A (poor man's Hasselblad! )a few years back. The pinhole to film distance was about 90 mm.

DaveT

 

[Willie Jan]

Steve,
I liked the link where he measures the hole size with the enlarger. That's a good solution!
http://www.pinhole.cz/en/pinholecameras/pinhole_01.html

 

[debanddg]

Earl Jones [earlj] at f295.org also sells pinholes (made for electron microscope) of various sizes for a dollar a piece I guess.. he had run an advertisement in that forum as well.. can save you some troubles..