What is interval? is it in mm?

[Glen H]

Hi,
I'm evaluating the Helicon Remote and have been having great fun stacking with it. I have a question about interval.

What is interval exactly? Is it a measure of focus adjustment in mm?
I'm used to using a manual turned Focus rail and I like to increment at.25 of a mm between shots.
Can the software focus my lens at .25mm per shot?
For example:
I would like to take 60 shot with .25mm focus difference between shots.
I can't get the setting in the software to go below 1 in the interval box.
I have a Nikon D5100 with a Sigma 105mm Macro lens AF...

Thanks
Glen

[cha cha]

Hi,
I'm evaluating the Helicon Remote and have been having great fun stacking with it. I have a question about interval.

What is interval exactly? Is it a measure of focus adjustment in mm?

If I am allowed to answer your question: no, IMO this is not possible. This would depend on the movement of a single step of the AF motor, and on the lens, on the current focus measurement of the lens, and on the aperture.

My guess is that this interval simply is the number of steps of the AF motor.

[Stas Yatsenko]

Interval is not a linear measurement unit when we're talking about a lens, it's more of an angular value that represents DOF indepently from the distance to subject.

[Glen H]

Hi,
I'm evaluating the Helicon Remote and have been having great fun stacking with it. I have a question about interval.

What is interval exactly? Is it a measure of focus adjustment in mm?

If I am allowed to answer your question: no, IMO this is not possible. This would depend on the movement of a single step of the AF motor, and on the lens, on the current focus measurement of the lens, and on the aperture.

My guess is that this interval simply is the number of steps of the AF motor.

Thanks Cha Cha!
That makes sense. The camera is not capable of making a fraction of a motor step
(stepper motor movement). You have the best explanation.