Pinhole Exposure Calculator by Richard Kollish has BIG MISTAKE!

[europanorama]

Printed out Richards 3 -part Dial-Calculator and compared the values with my lightmeter Gossen Variosix F.

Its very clear that the EVs/Light Values on the big wheel are 5 STEPS OFF.

10 should be 5 up to 15 instead of 20. then 16,17,18,19,20 should be added by setting minutes as m. not min due to lack of space. Light Value must also be moved.
maybe someone could contact Richard.
Here are multiple versions incl. Ilfords
https://www.thingiverse.com/thing:147404
first link not working, maybe revivable via archive.org
i am using this one:
http://www.rahji.com/pdf/koolish.pdf
Link inside this one found at archive.org
http://www.rahji.com/wordpress/2007/05/12/pinhole-exposure-times/

http://web.archive.org/web/20090221195707/http://ca.geocities.com/penate@rogers.com/diameter.htm

 

[europanorama]

Corrected Pinhole Exposure Calculator by 5 Steps
100 asa EV 13.5- 1/125 8/11
original is showing 3200-5 steps apart see image above

 

[europanorama]

I am very surprised that nobody until now has found this out.
Here is the proof:
https://en.wikipedia.org/wiki/Exposure_value
EV(100) base on 100 ASA
Richard at FB pinhole (there are multiple forums)still thinks he is right.
16 1/125 is EV 15 not 20. 5 stops apart.
he is stating 1/100 also.

 

[BrianShaw]

I don't think I looked at that one but Ilford's pinhole calculator is similar (if not exactly the same) and doesn't seem correct either.

 

[RalphLambrecht]

View attachment 182840 Printed out Richards 3 -part Dial-Calculator and compared the values with my lightmeter Gossen Variosix F.

Its very clear that the EVs/Light Values on the big wheel are 5 STEPS OFF.

10 should be 5 up to 15 instead of 20. then 16,17,18,19,20 should be added by setting minutes as m. not min due to lack of space. Light Value must also be moved.
maybe someone could contact Richard.
Here are multiple versions incl. Ilfords
https://www.thingiverse.com/thing:147404
first link not working, maybe revivable via archive.org
i am using this one:
http://www.rahji.com/pdf/koolish.pdf
Link inside this one found at archive.org
http://www.rahji.com/wordpress/2007/05/12/pinhole-exposure-times/

http://web.archive.org/web/20090221195707/http://ca.geocities.com/penate@rogers.com/diameter.htm

 

[BrianShaw]

Black Cat seems correct, though!

 

[europanorama]

article very interesting. one would be enough...
but doesnt rely on the problem with wrong EV-setting here.
btw: a pinhole sieve can be seen not photon sieve. photosieve has opaque center-pinhole-version has a center pinhole. seen in one of the links. maybe archive.org

 

[ciniframe]

I use my Gossen Pilot to meter and make my own exposure calculator on a 3X5 index card. Since I work with photo paper at ISO 3, 6 or 12 and f-numbers of f180 to f360, only two stops of range, I don't need a dial. Everything can be on the card. I use pinholes of a given size, then place them at a distance so as to have a whole f-stop to work with. Thus the angle of view falls wherever it does.