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MarcusH

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About MarcusH

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    Nebula

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    Finland
  1. I'm having a hard time wrapping my head around that behavior... Any chance you could perhaps upload a short video of the mount when it's slewing ?
  2. I too as @WanderingEye had a hard time wrapping my head around the idea that the two lower bolts would adjust the azimuth. But I think the crucial point here is that the wedge already was very well polar aligned (with the Polemaster) in the first place, probably < 1 arc min off. It's easy to see that the top bolt would adjust altitude as the mount will pivot on a imaginary axis that goes through the two lower bolts. But adjusting either one of the lower bolts is going to effectively tilt the mount ever so slightly. This tilt could possibly manifest itself as a bigger movement in the azimuth than the altitude making minute adjustments in azimuth possible (with a negligible movement in the altitude at the same time) . This would however require a good polar alignment from the start as the adjustment probably is only few 10ths of an arc minute. Or this could also be a totally nonsensical rambling about something I just don't understand....
  3. That was actually how I ended up buying a C11, I stumbled upon an affordable Hyperstar... Whatever guiding software you end up using is going to tell you your tracking accuracy. Sometimes it will put a smile on your face, other times you'll be ready to dig a hole in the ground and bury all your astrogear….
  4. Although I've owned an AZ-EQ6 for a year and a half I've have to admit that I never have tried the Alt-Az feature... This is what the manual has to say: "It may be more difficult to balance the R.A. (or Azimuth) axis in Alt-azimuth mode. Here are the balancing steps recommended for Alt-azimuth mode: » Balance the payload and counterweights in equatorial mode and mark the position of the counterweights. » Unload the payload and counterweights to set the mount in Alt-Azimuth mode. » Re-load the mount again by installing the counterweight at the marked position
  5. Clutch slipping in RA axis ?? With the RA clutch tightened up, can you move the RA axis (without using excessive force) ?
  6. That was a good rundown about SharpCap by @cjdawson. I can't remember if I ever tried to polar align using the C11 (either with or without an OAG), but I suspect that the field of view will be a wee bit too narrow for SharpCap. The good thing about SharpCap is that you can test your camera-telescope combination with the free version to see if you need to acquire some more gear, it just won't guide you through the whole process. You sure can do imaging with the AZ-EQ6 + C11, even deep sky objects. Try to get your guiding to < 1 arc sec RMS and adjust your expectations. An IOTD or APOD ? Likely not, but it still makes pretty pictures. And it's a versatile scope, go planet hunting from F/20-F/30 all the way to a wide field(ish) deep sky at F/2 with only a few accessories. Here's a few targets I've managed to image this season. Note that they are very much more skill / talent / knowledge limited than what they are equipment limited.
  7. Good to hear that you got that sorted out. As many have pointed out SharpCap is an excellent tool to tweak your polar alignment with. I'm using it too, but I always start out with a polar alignment using the polar scope. That will get me within 5 arc minutes really fast and it's easy too. The fine tuning is with SharpCap and if I really want to go all out I do a drift alignment also. I have the same setup as you (AZ-EQ6 + C11 XLT) and I can attest to that you will want to look into guiding sooner rather than later. Preferably an OAG as you have a big lump of glass flopping around in your tube.
  8. You do have the camera mounted to a scope (either guide scope or with an OAG to the main scope) ? With just the camera you won't see much more than a grainy picture. If you do have it mounted to a scope chances are you are out of focus or your backfocus distance is wrong.
  9. I was struggling with this one too, until I found an excellent tutorial on how to first calibrate the polar scope to the RA axis and then how to polar align: https://www.myastroscience.com/polaralignment
  10. That was some great pointers by @geeklee. It was also funny to read that we had exactly the same two game changers: SharpCap and Plate Solving. Can't remember if I read it somewhere or if it was in a Youtube video, but have you tried the iterative method of SC Polar Alignment ? What you do is a normal Polar Alignment, i.e. mount in home position - let SC plate solve - turn the RA axis 90 degrees - let SC plate solve again - adjust the Alt/Az knobs to minimize the PA error. When you're happy with the numbers you restart the Polar Alignment but now from the position you left the RA axis in (i.e. 90 degrees from home position). Once SC ask you to rotate the RA axis, you rotate it back to the home position. Ideally the PA error would be the same as in the first iteration, but more often you find yourself 1-2 arc minutes off. Now repeat this until you get as low of an error as possible. Drift alignment is still superior, but this usually gets me pretty fast to <0.5 arc minutes PA error in PHD2 guiding assistant.
  11. As the whole concept of periodic error correction was new for me and still is something of a dark art I relied heavily on info found on the net. I went the free software route (i.e. PECPrep). Essentially what I did was: 1. Used the AutoPEC in EQASCOM to record a PE curve (I used 9 worm cycles) 2. Imported the PE curve into PECPrep and used it to analyze, tweak and create a PEC curve. 3. Wrote the created PEC curve back to the mount After that I used the method described by user AhBok over at Cloudy Nights to store the PEC curve permanently to the mount (the summary is in post #14): https://www.cloudynights.com/topic/631100-a-well-averaged-smoothed-ppec-curve-with-eq6-r-pro/ I had to reread that post a few times before it sunk in, but it was pretty simple in the end. The good part is that you can store the PPEC into the mounts motor controller anytime, you don't have to do it at night. The importing to PECPrep is optional and can be used if you want to look at or tweak the PE curve. AhBok got some pretty impressive results by only using the AutoPEC feature of EQASCOM.
  12. Try to eliminate this if possible. Any slop, tilt or play especially in your guiding gear is going to cause you a lot of headaches. Your rig looks solid and well built with a payload that shouldn't cause any problems to the AZ-EQ6 whatsoever. It's nothing like the behemoth C11 I'm punishing my mount with (I have the same AZ-EQ6). Those guiding graphs look much like mine did last season. I kept reading that this mount was capable of sub-arcsec tracking with guiding and yet I was struggling to get it under 2" RMS.... Nothing I did seemed to improve things, and more often than not I didn't even know what I was doing. I too was ready to call it a day after the first season, sell my gear and do something else as I obviously was too stupid for this hobby.... Luckily we have this mandatory break up here in the north when any form of imaging is out of the question (apart from solar, obviously), no astronomical darkness for 4 months. That gave me time to put things in perspective and as you have done, I also stripped the mount down and did a regrease of the bearings. While I had the mount in pieces I decided to swap out the Chinese worm bearings for a good set of SKF bearings (nothing fancy as some super duper hybrid ceramic bearings, as I cannot see why those would be superior in a ultra-slow rpm application like this). I spent quite some time on trying to reduce the backlash between the worm and the worm gear. I really don't know how much backlash is too much, but when I run the guiding assistant I rarely get anything >200ms, more often than not I've been getting the backlash-so-small-that-nothing-needs-to-be-done message. So at 915ms I feel that there still would be room for at least a little improvement. I also spent numerous nights when it was not dark enough to image but plenty dark to test guiding in doing PEC training. And when I finally was satisfied I made it permanent (PPEC). The result? I went from the-best-I-can-hope-for-tonight-is >2" to a somewhat solid 0.6" - 1.0" RMS error. But I also have to stress that this was not due to the diy "hypertune" alone. I also perfected my polar alignment, mount leveling, balancing and my whole workflow during those semi-dark nights. Anything and everything you can improve on is going to help you in the long run. We also have to remind ourselves that even tough this is a capable little mount (AZ-EQ6), it still is (at best) a mid-range mass-produced mount with all the peculiarities and quirks that go into that territory. The RMS error range of 0.6"-1.0" that also @wimvb quoted is realistically the best we can hope for with repeatability, with a few outliers in the <0.5" and >1.0" range. My own personal best was a 5 hour session where the RMS error hovered at 0.38"-0.56" but I'm going to put that down as a once-in-a-lifetime occurrence. And what might work out for me, doesn't necessarily work for you. It's hard to tell from the picture of your rig if it is a permanent setup or if you set it up for every session. But if you set it up every session, try to make it a habit to set it up even when the forecast is so poor that you are barely able to get it polar aligned. Set it up, get everything going, tear it back down. Rinse and repeat. Try to make it second nature to set it up so you don't even have to think what you are doing. I did this as a part of perfecting my workflow. And I did it so many times that I now can set up my rig in pitch black darkness with my eyes blindfolded and one hand tied behind my back... I went from a totally ridiculous and mind boggling 4-5 hour setup time to 15-20 minutes. And even though my normal setup consists of 3 PC:s, an imaging camera and focuser all connected wirelessly + a myriad of USB connected equipment, I have yet to loose a single sub this season due to equipment acting up (fingers crossed...). Those few precious nights that are perfect for imaging is now spent imaging, not troubleshooting. And as far as your images go, sure, you can beat yourself up by pixel-peeping them and trying to find all sorts of imperfections. Or you could take step back, zoom out and look at them for what they are - stunning examples of something incredibly beautiful. I'd be inclined to say that you give people with twice your budget and 100x more clear nights a run for their money. Sorry for this long winded, mindless and pointless rant, but hopefully you can find something hidden in here that keeps you hooked to this brutally unforgiving yet fascinating hobby.
  13. I've never tried it with Sharpcap myself, but I have All Sky Plate Solver, CdC and PHD2 all connected to the mount (AZ-EQ6GT) at the same time and never had any problems.
  14. Third time's a charm, as they say. Either that or you go down in history as the unluckiest Esprit buyer ever...
  15. I have the same mount as you and my location is also Bortle 4 and the Polaris is clearly visible in the polar scope. When you say you can't see anything through the polar scope do you mean that you can't see any stars at all or just the Polaris ? While Polaris is quite bright, you don't have to be much out of focus for it to dim pretty rapidly (I know, I lost it a week ago and was puzzled until I noticed I was way out of focus). You could try to focus the polar scope in broad daylight on some distant object, preferably a few miles away. That way you would be roughly in the ballpark with the focus and you could tweak it further once you get an hint of Polaris in the scope at your next outing. Once your spot on it really pops out.
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