So, to follow up on my illuminator issue, some hopefully useful info I learned today.
First thing, I learned a polar scope can have three issues:
- polar scope not aligned with the ra axis
- reticle not centered in the polar scope
- reticle not aligned with the illuminator hole
Oddly enough, or rather unluckily enough, my polar scope exhibited all three issues, the most apparent one being that the reticle was not illuminated when set to 12 o'clock being straight up. See my earlier posts for that. The kind folks at iOptron suggested to rotate the polar scope (the procedure in the first pdf I posted), but that turned out not to be the case. So let me go through each of the three issues I listed above and mention which procedure I think should be performed to fix each.
Polar scope not aligned with RA axis.
- To check: release the RA clutch and rotate the RA axis, while looking through the scope at a fixed distant object.
- Symptom: the entire image wobbles around (not just the reticle, the entire image).
- To fix: follow the procedure in the PolarScopeRotating.pdf file I posted. I'll be honest and say I haven't done this yet. I'll post my notes on it once I get brave enough to dive in it.
Reticle misaligned (miss-centered in the scope).
- To check: release RA clutch and rotate the RA axis, while looking through the polar scope at a fixed distant object
- Ignore if the entire image wobbles around, and instead look at the very center of the reticle as you rotate, noting any moving with respect to the fixed object you centered on.
- Symptom: If the center of the reticle moves around that object as you rotate, then the reticle is misaligned.
- To fix: follow the procedure in the PolarScopeAlign.pdf I posted a link to. I'm also including a pic I took of the back of the mount with the back plate removed and the eyepiece removed as well, so you can see how the reticle is mounted in the polar scope. The reticle is mounted in a metal collar, which is in turn encased in a soft clear plastic sleeve. I believe that sleeve also transmits the light from the led to the reticle to illuminate it evenly. Note the three set screws press against that soft sleeve. So it's fairly easy to move that out of alignment. You adjust the three set screws to center the reticle in the polar scope.
VERY IMPORTANT NOTE: do not loosen the set screws too much, you run the chance of the reticle sleeve not pressing against the collar enough, causing the reticle to rotate. This actually happened to me. To rotate the reticle back to its proper position, see my third fix, below. So work using half turns to loosen and tighten the set screws. Also don't overtighten, as it can crush that clear plastic sleeve.
Reticle 12 o'clock not aligned with illuminator led
- To check: leave the front cover on the polar scope. Turn the mount on and turn on polar scope illuminator. Release RA clutch and rotate the axis until the 12'oclock position on the reticle points straight up.
- Symptom: reticle is not illuminated in that position, but if you rotate the ra axis around, it will become illuminated at some other position.
- To fix:
First, take off the back plate from the mount. There are three allen screws. The PolarScopeAlign.pdf shows you how.
Then unscrew the eyepiece from the back of the polar scope. It just unscrews. Then you will see basically the image I posted. Note the led light. I don't have it shown, but looking from the side, where the three adjusting screw are, there is a larger hole to allow the led to illuminate through to the reticle. The pdf I mentioned shows a pic of it at the very beginning.
Now, rotate the ra axis until that hole is directly underneath the led. Tighten the clutch on the RA axis so it doesn't move.
So now the polar scope is rotated where the led should illuminate it. Loosen very slightly and very evenly the three set screws.
Take a large slotted screwdriver, or anything that will fit into the two slots on the reticle collar (careful not to scratch the glass) and gently rotate the reticle until the 12'oclock position is straight up towards the led (like in my pic).
Tighten the set screws back up, gently and evenly.
Screw the eyepiece back in
Before putting the plate back on, check to make sure the reticle is still centered in the polar scope.
Screw the back plate back on.
Hope this helps.