using palm software Vade Mecum (by Wheeler)

[pellicle]

Folks

I've been using this software on and off for some time. I recently started to experiment with using one of its features, and suspect I might have found a bug (either that or simply its not behaving as I expect)

I'm using the DOFd2 calculation to try to find the f number needed to get the DoF for a particular focus spread. As I understand it, the software takes the distance between the closest and furthest subjects divided by two and computes the f number required (taking into account parmeters set elsewhere on desired CoC; Lens focal length; film format)

I decided to start with a simple calculation, I focused first on an object about 6 meters (guessing by eye) away and measured the 'extension' as being 190mm. Returning the standard to infinity measures 180 mm (no surprises).

So, the spread is 10mm, thus I enter 5 into the calculation input.

Here's where it goes south, and I get results I can't figure out:

Bellows Factor = 2.44
u = 0.5(m)
FrontDOF = 15.3 (mm)
BackDOF= 16.3 (mm)
Adjusted N = 16_7

can anyone suggest if this is user error, or software error.

thanks

 

[donbga]

Folks

I've been using this software on and off for some time. I recently started to experiment with using one of its features, and suspect I might have found a bug (either that or simply its not behaving as I expect)

I'm using the DOFd2 calculation to try to find the f number needed to get the DoF for a particular focus spread. As I understand it, the software takes the distance between the closest and furthest subjects divided by two and computes the f number required (taking into account parmeters set elsewhere on desired CoC; Lens focal length; film format)

I decided to start with a simple calculation, I focused first on an object about 6 meters (guessing by eye) away and measured the 'extension' as being 190mm. Returning the standard to infinity measures 180 mm (no surprises).

So, the spread is 10mm, thus I enter 5 into the calculation input.

Here's where it goes south, and I get results I can't figure out:

Bellows Factor = 2.44
u = 0.5(m)
FrontDOF = 15.3 (mm)
BackDOF= 16.3 (mm)
Adjusted N = 16_7

can anyone suggest if this is user error, or software error.

thanks

I found Vade Mecum so difficult and irritating to use I deleted it and have never missed it.