box size vs. movements for camera

[thereza]

So when I measure the area of the box, I get 14.35mm for X and Y. But when I enter that and click on something, it doesn't move to the center. I empirically found that 16.5mm is a good setting for getting that to work. My X and Y are set to 1.8deg/step at 40mm/rev. Not sure where the error lies.

Also, the video portion of the hardware seems to crash. The draw rectangle will throw out of memory exceptions sometimes and I just had an error in ZoomFunct. Will investigate further.

Couple comments :

- I made my cameras face each other when homed. This became almost an issue when I needed to place the homing dot, but placing it on the diffuser for the upward camera worked well.

[JuKu]

There is no correction for perspective error on the clicks, so that might be a factor; I get good results by putting in the true value. On the other hand, the system really tries to figure out the size of a pixel in real life. When it is really used in movement, if the correction turns out to be large, the system moves closer and takes another look. In other words, minor errors here shouldn't be a big deal. In this case, there is 13% mismatch somewhere. So, if the system finds itself being more than 0.5mm off (this is the usual case), it goes closer. The worst case is that it ends up just inside 0.5mm. Then, it measures and uses the remaining error. So, the worst case from this is 05mm x 13% = 0.065mm.

> My X and Y are set to 1.8deg/step at 40mm/rev. Not sure where the error lies.

This is strange (and somewhat alarming): You shold have 0.9 step motors. ??.

[thereza]

Nope, 1.8. From the part number (17HS19-2004S) :

http://www.omc-stepperonline.com/3d-pri ... -p-18.html

what part did you intent to mail out? -r

[JuKu]

The equivalent 0.9 deg. part, the 17HM19-2004S. Email to all customers went out a moment ago.