Can you measure focus distance and manually set it in Vuescan as in Nikonscan?

[AFairley]

My Nikonscan workflow to deal with the curvature of slides is to measure the focus points at various places on the slide using Ctrl-focus, and then, based on the range of focus distances my measurements returned, make several scans using focus bracketing by manually setting a series of focus distances (set in the Nikonscan software), and then stack and mask in Photoshop to give me grain-sharp scans across the entire image.  I wonder if this workflow can be replicated in Vuescan?  I see how to set the focus point using the x & y offsets, but don't see a way to get a numerical value for the focus distance at the selected offset and then manally enter that value to perform a "manual focus" scan.  Is that possible?

Thanks

[BartvanderWolf]

My Nikonscan workflow to deal with the curvature of slides is to measure the focus points at various places on the slide using Ctrl-focus, and then, based on the range of focus distances my measurements returned, make several scans using focus bracketing by manually setting a series of focus distances (set in the Nikonscan software), and then stack and mask in Photoshop to give me grain-sharp scans across the entire image.  I wonder if this workflow can be replicated in Vuescan?  I see how to set the focus point using the x & y offsets, but don't see a way to get a numerical value for the focus distance at the selected offset and then manally enter that value to perform a "manual focus" scan.  Is that possible?

http://www.hamrick.com/vuescan/html/vuesc28.htm#inputautofocus

You typically autofocus on the spot you want, then switch to manual focus (which should give the focus position found) and vary the focus distance. Due to potential heating up of the film inside the scanner, if you wait too long the focus plane may have moved. Just let the film acclimatize a bit inside the scanner before doing the actual setting of the focus position.

Cheers,
Bart

[AFairley]

Thanks, Bart.

That is what I was afraid of.  With the Nikonscan, I may measure focus points varying between, say, 150 and 175 on one slide, but only 160 and 165 on another.   So for the first I would bracket at focus points of 152, 159, 166 and 173.  On the second on, I would just do one scan at 162.  It looks like with Vuescan I wouldn't know which scenario I was dealing with.

Thanks again