Error on stage calibration

Hello (again!),
A huge relief I got all 3 motors working (wiring and my general panic I guess).
I receive this error on calibration. I wonder if it has to do with the torque being too much? William has assured me they have never had this problem. So perhaps I am wrong? I do watch the x-axis at least move during calibration…


Thank you.

I should point out that I loaded sangaboard.ino and then ran some commands like mrx 1600 (which I interpret to mean take 1600/8 steps == 200…all worked)…

If this is the first time with this microscope I would skip the stage calibration and use the webapp to look at the image and to try moving the sample around. Does it move, does it focus, and is the illumination centred. The camera calibration needs no sample and a reasonably well aligned illumination, so that no parts are too black. The stage calibration needs a sample that is well enough focused that you can tell when it moves.

Thank you @WilliamW !

Q: Do you have the STL to the updated small gears that seem to grip better? I’d like to try them…I recall there was a SCAD file just hoping for an STL like the others?

Thank you.

This one? Tighter fit small gears - Contributions - OpenFlexure Forum. The compiled STLs from the merge request linked in the third post are not there anymore, I think the built documents are trimmed after a certain time. I think there will be STLs somewhere in the current master on Gitlab, but I only know the route to tagged or released versions, sorry.

Thank you @WilliamW. Yes, that’s it. I now have the 3 axes moving as (I think) expected I cannot seem to focus. It seems WAY off and auto focus gives me the above error. I keep clicking on auto focus (fine) and it does move the x axes a bit before throwing up it’s dialog box. Any advice on focusing? Thank you.

The fast autofocus is usually the best, unless you have a tricky sample. For any of the autofocus methods you need to be reasonably close before you start. Does the z-axis motor move if you make a z-movement of say 400 steps in the z-axis?
Which optics have you got? The lens will need to be perhaps surprisingly close to the slide. With the simple lens from the Pi camera the sample needs to be about 1mm from the lens. If you have the sample on top of a slide then that means the lens is almost touching underneath. A 20x objective lens s similar. A 40x or 100x will need to be less than half a mm, almost touching the sample. Sometimes it is easiest to remove the z-motor so that you can get a feel moving by hand.

Thank you very much for your reply @WillamW!

Yes. Given the movements (as i understand it) are 8 sequences in a step, 2038 steps for a full turn on a 28BYJ-48 motor I was assuming 400 “steps” is really 400/8 = 50 steps 50/2038 = small number, so I was putting in values like 1000, heck even 10000, -10000.

What are the consequences? Note: I couldn’t tell with my eye if the stage was actually moving…in the Z axis it must have been because it broke the lens cover.

With that said, when it starts moving, I most times I get this annoying/scarry/ohmy popup (seems like the error message is being generated in

Which optics have you got?
40x from aliexpress

I am new to microscopy. I want to view soil samples. I could try the lens off my Swift microscope, or if there is a recommended, I could try that one.

The LED illumination light and the optics are not in line. I don’t recall this being discussed within the assembly docs… Is it ok to have them off?

Linking this thread to Gears move great, positional errors abound - Request Help - OpenFlexure Forum