I see - thanks for the explanations. I am not sure how it is done by Cognisys, but my simple setup seems to work perfectly fine. I have a similar maximum speed (5 mm/s), and my acceleration/deceleration limiter is such that it takes 0.8s to get to the full speed. The rail only moves when you press a button (two buttons for <- and -> movements). In my experience, even at the highest practical magnification 5:1, this works well: a sequence of a few quick key presses/releases allows me to find the starting point with the um accuracy. The time to make a full rail rewind is 12.4s. So it is both fast and accurate.ChrisR wrote:¶Speeds - imagine a rig surrounded by lights and reflectors. You want to change an objective, so you want to withdraw perhaps 100mm or more.
Then you need to approach the focus point to find it - slowly.
¶Remove Toff after last shutter operation:
Using mirror lock, 2 shutter operations may be needed, hence:
Move rail
Settle
First shutter
Toff 1
Second Shutter
Toff 2
Move rail
etc.
Toff 2 is redundant but can't be set separately or removed.
600 shots at 2 seconds wasted = 20 minutes wasted.
You can work around it by adding an extra, single, manual shutter press so the first exposure is made after "settle", then you don't need any Toff, but it's easy to mess it up.
¶Various inputs and output connections:
Focus lights on/off, flash trigger, vibration sensor, flash sensor, alarm....
Regarding the mirror lock, settle time etc - my whole idea was to ignore all this so I can create a super-fast stacker (up to 4 fps with my camera; for live subjects) - as long as my main source of light is a flash used at a fraction of its full power, resulting in such short impulses (100 us or less) that everything is effectively frozen - motion blur (camera moves continuously; of course in reality it moves by microsteps of 2.5 um, but the combination of the rail/camera inertia plus backlash should turn this into pretty much smooth continuous camera motion), rail vibrations, mirror lock etc. I don't see any evidence of these motion artifacts in my 5:1 shots - everything appears to be sharp down to the theoretical diffraction limit. But I am sure some people will have strong and differing opinions on this matter.
It should not be too hard to add another, non-continuous mode of rail operation to my code, but so far I am not convinced it would justify the efforts.