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Originally Posted by Fox
Sorry Deimos, I am obviously still not quite following you here (no offence! it's sometimes hard not being able to see a problem 1st hand, and only having text to go by).
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Hey Fox,
No offence taken. I'm new to this field and am probably not explaining myself using the correct terminology.
The text and patterns of the illuminated reticle inside the PAS appear to be in their correct orientations, based on the diagram on page 52 of the
Meade LXD75 series manual (935k PDF warning) and the Octantis pattern I attached to my earlier message.
I'll try to explain the problem with the visuals when looking at things through the PAS.
The view through the PAS, as opposed to what's seen on the reticle inside it, is left-right mirrored and flipped top-bottom as well. This is confirmed by looking at terrestrial objects - trees are hanging down from the sky and signs read right-to-left as if in a mirror.
If I rotate the azimuth to the right I would expect the star field viewed through the PAS to scroll to the left as the FOV pans to the right across the heavens, but instead the star field scrolls to the right. Likewise, if I lower the altitude (latitude) I would expect the star field viewed through the PAS to scroll up as the FOV drops down through the heavens, but instead the star field scrolls up.
So it's not just near-field (terrestrial) objects that are flipped and mirrored.
The problem with this is that it makes lining-up Octantis on the reticle impossible - the Ups-Chi side of the reticle pattern is towards the top of the reticle, whereas the Ups-Chi side of Octantis as viewed through the PAS is towards the bottom of the reticle (even though it's on the top or closest to Octans proper in the sky). If I rotate the RA axis through 180 degrees to at least make the Ups-Chi side of the reticle and star field versions line-up then the the opposite side (Sig-Tau) won't match because its two stars are swapped out of position (note: this means Ups-Chi are swapped around as well).
Hope this makes it clearer.
On a brighter note, I did go through about six alignment sessions with the mount tonight before the clouds rolled in. Using Achemar and Formalhaut for two-star alignments I eventually got down to results of 37'^ 0'<. I could goto Alpha Cent. and Hadar fairly accurately and was still within 4 degrees of Aries (just) when swinging around to the other side of the sky.
I'll contact the Meade agent tomorrow to see if he thinks the PAS is OK.