Question about Detent rings?

I have looked through the guide book and frequently asked questions and can not seem to get the info I am looking for. How do you determine what lens goes with what Detent ring? Is it the N=18 so my lens choice would be a 18mm? Seems like this makes sense with the number of dents per plate. Hope this is the right place to ask.

Cheers,

Graham Twomey

Re: Question about Detent rings?

Quote:

Originally Posted by

**Grahamtwomey**
I have looked through the guide book and frequently asked questions and can not seem to get the info I am looking for. How do you determine what lens goes with what Detent ring? Is it the N=18 so my lens choice would be a 18mm? Seems like this makes sense with the number of dents per plate. Hope this is the right place to ask.

Cheers,

Graham Twomey

some body may come up with a table of focal lengths etc.

However if you devide the number into 360 Degrees it give the angle between a pair of holes .

18 holes = 360/18=20 degrees however you must still allow for over lap.

Various calculators can be found here.. http://www.tawbaware.com/maxlyons/calc.htm

And perhaps more useful here.. http://www.frankvanderpol.nl/fov_pan_calc.htm

Re: Question about Detent rings?