There are three of us that have a combined equipment setup for astrophotography. One of us has ordered and received a LX80 (we have been using his LXD55 ). During first light Friday night, we found an issue with it not tracking properly in RA, which I’ll explain. The issue has only been not tracking properly in RA. The DEC has been good. The gotos have been good. The LX80 seems fine except for the RA tracking. Also it is much more solid/stable than the LXD55.
The guy that bought the mount called Meade Monday. He told them what it was doing. He also asked what the RA ratio value should be as default, in attempt to verify that. Meade told him that they would have to call him back. Didn’t hear back on Monday, he called again this morning, got no call again so called back very late today. He was now told to e-mail the issue to them. He had to go to work and will have to e-mail them after he gets off work.
We discussed it and he wanted me to ask here - Can someone that has a LX80 please check their hand controller to see what value the RA ratio is? I hope it isn't wrong to post what ours is showing. Ours had +2.75075 as the RA ratio and +2.75077 for the DEC ratio. After having absolutely no luck, as a debug step we did temporarily change the RA to see if it affected the situation. We set it about +8 and the drift then went the other way. When we set it to about +6.75 that caused the star to be just about steady then. The RA ratio has now been re-entered to +2.75075 as it originally showed. We did see a value close to that on another site. The value they showed listed it as being LX90 & LX80. Is that correct for both? The reset of the audiostar hand controller still showed +2.75075 but it has huge drift at that.
Also, I don’t believe we’re overlooking something but please say so if anyone notices something we might be overlooking.
Friday night, the mount was physically setup in EQ/polar mode, verified the hand controller also showed polar/EQ mode. The mount was balanced in both axis - picture is attached (80mm F7.0, 66mm F6.0, flip mirror & DSI pro, diagonal & eyepiece).
We did the same alignment routine we’ve been doing with the LXD55. Polar align roughly eyeballed. Then one star alignment (which goes to Polaris first), physically adjust the mount to center Polaris. It then picked Arcturus. It went near Arcturus (goto was better than the LXD55 usually does). Arcturus was then centered using the hand controller = successfully alignment. We then did gotos back and forth between Polaris and Arcturus. Each time when at Polaris - physically adjust the mount to remove out about half the error. Then on Arcturus center with hand controller and sync. Once we get the alignment error out enough that both stars are in the field of view with a 12.5mm eyepiece in the 80mm F7.0, we would then focus cameras and do a drift align using PHD guiding and really nail the alignment, then guide and image (that has been working well on with the LXD55 – see the FLI8300C gallery of starsabove.net).
After getting alignment close going between Polaris and Arcturus, when we went to near the meridian to do the 1st part of the drift alignment, the LX80 was not tracking worth a hoot in RA. The DSI pro through the 66mm F6.0, showed the stars drifting left to right across the screen about 3/16 to 1/4 of an inch every two seconds exposure with the DSI. We’ve never seen drift like that on the LXD55 at that same step in our routine – the star has always been mainly steady while just looking at it on screen. PHD would not calibrate due to the star kept drifting out of the star search box.
We have reset the hand controller, verified the hand controller also showed polar/EQ mode,motor calibration routine has been run a couple of times, trained the drive a couple of times, Started all over on polar aligning several times. Verified the hand controller set for sidereal tracking rate. Turned targets to terrestrial to see if the LX80 was tracking at all in RA – it was – the star drift got worse as it should have when set to terrestrial targets , then turned targets back to astronomical – back to same bad amount of drift. We did set it up in alt/az and did an alignment. That showed the star drifting the other direction – right to left (but some less drift and the star would move slightly up a couple of frames then down a couple of frames then repeat while drifting left – we don’t normally do alt/az but wanting to try it to see how stable that tracking was)
Sunday morning, Venus was put in the field of view on the eyepiece with the mount set up as EQ and Venus did drift out. When it did the DEC was still good – only off in RA. I wasn’t there helping Sunday morning, so this time the other guy did all the setup/balancing/alignments, so more than one person has set it all up with the exact same results.
As mentioned earlier, the gotos have been good. The mount I didn’t think was very noisy on normal slew and goto was very quiet with the quiet slew mode turned on. The LX80 fit and finish is good. Much easier to balance as both axis are much smoother than the LXD55.
I would think that if there was some big mechanical issue, gotos would be off but they are good.
We would appreciate someone letting us know the default RA ratio value their LX80 shows. Let us know if we’re being brain dead and overlooking something obvious or other ideas on the issue that might help isolate what's happening. Maybe there are something more that could be tried before he gets feedback from Meade.
Once it is acting properly, we plan to pulse guide it through the hand controller with PHD like we've done with the LXD55 and I'll let everyone know how that goes.