I did initially think it was down to DX/FX sensors, which gives the Tamron an effective focal length of ~135mm on the D7100, but am not 100% convinced. Especially as the instructions for Helicon clearly say you should always use the lens' actual focal length when calculating DOF, CF and steps.

The ...

Quick update....

I played with this for many hours yesterday and eventually found it was just the Tamron lens that caused the issue, 3 other lenses I tried worked fine.

After much head scratching I decided to see if this advice on correction factors helped: http://www.heliconsoft.com/forum ...

Hi All,

I have searched for a solution to this issue before posting but could not find anything, hopefully someone can help?

Here's what I am doing...

- In Remote I set up the nearest and farthest focal point and save them to A and B respectively.
- I click the buttons to re-focus the camera to ...