Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- Losmandy_users
- Messages
Search
|
Replacing Old Clutch Discs in a CG11
I wanted to pass along my experience with clutch disc? R&R on an old apparently never used Celestron G11 mount.? I believe never used because upon?inspection of the RA and Dec shafts?they did not appear to have any roller bearing track marks.? The original discs were completely saturated with grease [remnants of white grease].? They were stuck as if melted onto the mount's surface.? Once gently pried off and the surfaces cleaned, there remained faint very thin what appeared to be deposits left by the old discs.? Alcohol 99% then Brakleen failed to remove what at first I thought were smudges.? Close inspection of the old discs revealed what I would term delamination.? The marks on the alloy surface matched depressions in the old disc's surface.? I placed a call to Losmandy, they never encountered this and suggested using a razor blade to remove the residue. ? I took great care not to nick or scratch the surface in any way.? The material/residue was very thin and very slick making the (new) razor blade skip over its surface, the deposits would not budge, still visible and not easily felt with a fingernail.
Ok, bring out and test all types of solvents.? Finally some very strong Epoxy Paint remover, briefly applied then wiped off worked.? The spots/material was gone and I had not left any razor blade marks.? Whew. While on the clutch disc R&R subject let me add: Installing?the Upgraded Dec Clutch Disc, which was slightly larger even after trimming, the new disc?came into contact with three sharp protruding edged threaded holes on the Dec surface.?I then chamfered the?3x threaded holes?slightly removing those?protruding sharp edges.? Why I did not reduce the diameter of the disc to avoid those holes?? Well after careful, and time consuming trimming, using rhe Dec surface edge as a guide,?now having it?round and with out any edge/surface distorting cuts, the circle was just too pretty and why would you want less friction material anyway? Another repair, which was not immediately noticed,? was the need to replace a bent Azimuth Adjusting SS Threaded Shaft.? Look for wobbling Adjuster Knobs while rotating the adjuster.? The !/4" -28 x ~3" rod could have easily been bend if the mount got bumped. Also the Losmandy Azimuth SS shaft (AS)?as received had extremely sharp and rough threads which I thought might chew away at the brass dowel that rides on this threaded shaft.? Remedy; judicious use of Swiss files. And after reassembly of the AS and adjustment, a dry run revealed that the original nylon washers had become pitted and the rotation was not silky - simple fix add 2 per side -?new 1/4" nylon washers.? Adjust for light contact.? Blue thread lock on one knob to shaft.? I could not source Mylar washers, maybe next time.? Why two - look closely at their surfaces one side is smooth and the other has manufacturing dimples.? I place the smooth sides in contact w/ the alloy surfaces.? Obsessive - yes. |
|
Re: PoleMaster Add-on... Anybody use one?
For what it¡¯s worth I use the SharpCap polar alignment tool with an imaging camera and telescope combo that results in 0.89 arcsec/pixel and a FOV of 1.15?x0.9?. ? This ?combination always works. ?Any wider FOV¡¯s should work, all the way up to a camera on a guide scope.
A while back I had a little trouble with a longer FL scope (more like 0.7 arcsec/pixel, same camera) but SharpCap must have updated their plate solving database as this combination now works in the latest versions. As with any platesolving, you have to be in rough focus. ?But sharp focus isn¡¯t necessary (but certainly donuts won¡¯t work on an SCT). ?I can usually get platesolving to work even when my HFR is as bad as 3x the value at sharp focus. |
|
Re: PoleMaster Add-on... Anybody use one?
Sonny,
Love the Polemaster for quickness and ease, and the pretty close polar alignment. But I always follow with a PHD2 drift alignment for taking long multi-frame exposures over the course of the night. The closer you are to the North Celestial Pole, the less PHD2 (or other app) has to make corrections to stay on target. Also the frame will stay more centered and less cropping will be required during image processing.? You may also wish to use PemPro to reduce the periodic error from the gearing. You can download for free and upload the correction curve to the mount before the trial period expires. Then with reduced PE, PHD2 can perform better still.?In the end you'll have rounder stars and be able to do longer exposures. I have a permanent setup and can go for numerous weeks before any mount tweaking after doing the aforementioned. Cheers, John |
|
Re: PoleMaster Add-on... Anybody use one?
Sonny you have a lot of feedback on polemaster and alternatives
I've used them all as well.? polemaster is overall the easiest. you don't have to worry if your scope is too long, if you are in focus, etc. you simply plug in the polemaster, run their wizard and you are done. It gives you really good polar alignment, more than enough for observing, and perfectly fine for imaging. yes, it's about $300. However, it's not the most accurate PA If you want an additional level of precision in your PA, sharpcap is probably your best bet (others have mentioned similar products). It also employs a wizard type approach and walks you through the process. it has the added? advantage that it's continuously plate solving and using your main scope's focal length, so it's tremendously accurate. it's also something like $10. However, you have to have your telescope reasonably setup and in focus, I've been using sharpcap lately for unguided imaging and it's really made a difference over polemaster so it depends a bit on your needs and some of the other details of your setup and how much accuracy you need Brian |
|
Re: PoleMaster Add-on... Anybody use one?
¿ªÔÆÌåÓýI own a StellarMate, an ASIair, and PoleMaster. ?All of them do polar alignment.BUT¡ the StellarMate and ASIair do the polar alignment using the camera on your main imaging scope ¡ which may (and usually does) mean that you have a very narrow true field of view. ?The scope needs to be pretty close to having a good polar alignment already ¡ª and these tools can help you refine it. The PoleMaster has a fairly wide-field of view ¡ª 11¡ã x 6¡ã. ?That means your starting position doesn¡¯t need to be *as* precise and the PoleMaster still works. ? The PoleMaster does work exceptionally well ¡ and saves a lot of time if you don¡¯t have a permanent setup and have to re-align every night. Clear Skies, Tim
|
|
Re: PoleMaster Add-on... Anybody use one?
¿ªÔÆÌåÓýOr, for half the price of a PoleMaster, you could get a StellarMate, which gives you software to do image acquisition, session planning, guiding, and polar alignment, running on a stand-alone computer that you can attach to the mount to reduce cable clutter. It uses your existing cameras and can do the polar alignment with or without a view of the polar area.?PoleMaster seems to me to be most useful for visual astronomy, when one doesn¡¯t already have a camera attached to the scope.? ??-Les On Jan 18, 2020, at 1:35 PM, sonnyedmonds@... wrote:
|
|
Re: PoleMaster Add-on... Anybody use one?
So I feel a built guilty about potentially taking business away from QHY, but the SharpCap and PoleMaster techniques are both just a few minutes of work, and both give great accuracy. ?$10 vs $300, your choice (assuming you have already have a camera, that is.). ?SharpCap¡¯s routine doesn¡¯t require pointing at the North Star; you can be a couple of degrees away.
Do a web search, ¡°PoleMaster vs SharpCap polar alignment¡±. ?Lots of discussions at CloudyNights and other sites. ?Lots of fans of both. ?Either works well for everyone. ?Personally, I tried SharpCap first and found too many other uses for the $300 on other equipment. |
|
Re: Meridian Flip G11 with Gemini 2 and SGP
Sound good. ?I'm a little less complicated. ?I just tell SGPRO to flip 10 minutes past meridian and then center and Plate solve to get on target. ?I never messed with the Gemini settings. ?It always proved to me that the limits it came with worked fine. ?I do have a pier extension on my tripod just to note.
but I've never in two years had a collision or failure to flip. |
|
Re: Initial Setup of the Mount
Unfortunately I don't have a pier so I set up in various places in the yard to avoid trees. ?I first decide on my target and then use an App called "Sky View" to find where in my yard I will get the most time on a target. ?Then like others stated I use a compass App to make sure my tripod is pointing correctly. ?After that I set up and shoot.
one other thing I do if I'm going to be in the same spot for a long time is take black spray paint and mark exactly where my tripod legs were standing so when I go out the next night I don't have to repeat pointing and balancing. if someone were to fly over my yard during the day and see those marks you would think UFO's had landed in my yard. hope this helps. Sean. ? ? |
|
Re: PoleMaster Add-on... Anybody use one?
¿ªÔÆÌåÓýI use pole master and it¡¯s great. You need the ioptron ieq45 adapter for it. ?In addition I use a Microsoft surface with a USB adapter so I don¡¯t have to move my laptop out to the scope. With this combination I am polar aligned in under 5 minutes.?Dave Sent from my private jet On Jan 18, 2020, at 1:35 PM, sonnyedmonds@... wrote:
|
|
Re: PoleMaster Add-on... Anybody use one?
Thanks guys,
What I was doing was leaving my mount set up and covering it. So it was always very close to PA. Each night I would set my telescope in the saddle, then tweak the ELV adjustment to bring Polaris to the crosshairs in my imaging camera. Then run my alignment. It always brought my objects within my main cameras view when finished, and I'd manually center my intended object, then set up PHD2 to guide on it. So there lies why I wonder if it will benefit me. I could easily see it if I moved my mount around. Or if I traveled to a dark site. But wonder about day to day use. I suppose if I have it, I can choose if I want to use it. But if I don't have it, I can't choose at all. Just seems like something I should add to a new mount since I'm taking a quantum leap jumping up from an AVX that was a PITA. |
|
Re: PoleMaster Add-on... Anybody use one?
I can second the Polemaster suggestion. I don't do long exposure AP, but get 2 min unguided subs with my G11g and a 10" RC.? Since I set up and teardown every time, its accuracy and 2 min alignment are a godsend, indeed.? Matt On Sat, Jan 18, 2020, 2:02 PM <smolony@...> wrote: I absolutely love my Polemaster and would never go back.? I set up my G11g, polar align and Plate solve to my target all within 10 minutes.? Trust me, at 54 staying in my chair to polar align is a treat I won't give up. |
|
Re: PoleMaster Add-on... Anybody use one?
¿ªÔÆÌåÓýI use PoleMaster, and it¡¯s a godsend!? It had become practically impossible for this old man to twist his old body in the contortionist shapes necessary to use the polar scope; PoleMaster is easy and kind of fun.? Warning:? The user¡¯s manual is worse than useless, but there are excellent instructional videos on YouTube, and the user interface for PoleMaster is excellent. ? From: [email protected] <[email protected]> On Behalf Of Don Holmgren ? I know there are lots of PoleMaster fans here8. ?It must be a very good add-on. |
|
Re: PoleMaster Add-on... Anybody use one?
I know there are lots of PoleMaster fans here8. ?It must be a very good add-on.
If you¡¯ve got a fairly good view towards the pole, and you already have a camera on your telescope, you can always upgrade SharpCap for about $10 (?IIIRC) and use the polar alignment tool there. ?It uses plate solving and a 90? rotation that you perform to tell you how much to adjust the altitude and azimuth nobs (interactively - it¡¯ll continuously do the plate solve and tell you the current alignment error as you adjust the knobs). ?Definitely worth the small license fee. ?And definitely easier for polar alignment than the polar alignment assistant in the Gemini II. I find I can get even better alignment with drifting, either using the drift alignment assist tool in PhD2 or PemPRO. ?But I always start with the SharpCap tool. For sure remote observing from your armchair is the way to go. ?When the temperature drifts towards 0?F and below I am always grateful that I¡¯ve put in everything I need for remote work. Have fun! - Don |
|
PoleMaster Add-on... Anybody use one?
I'm shopping for accessories for my soon-to-be-purchased GM811G mount, and debating with myself if a PoleMaster8 add-on would make my life easier.
I think it might, but never used one before. So wanted to ask what you experienced experts think. Worth the $300? Friends like it with their mounts (Celestron's, Orion Atlas, Sky Watcher, ad nausem...)... I've been successful without one, but at 70 (almost), I'm thinking armchair Astrophotography. Mount the telescope, plug in some wires, WiFi the Baby Dell, and go inside to have some remote fun. What do you think? |
|
Re: GM8 Belt drive stepper mount
Makes sense with the higher resolution telescope to help the tracking. I have a focuser I built using UNO and a small inexpensive (ridiculously so) stepper motor. I took a side road from the originators plan and put a 12 volt DC motor in mine so I didn't have to A. Step down the 12 V to 5 V. B. Get more torque. I put the drive on the fine adjust of my telescope's focuser and the total gives over 23,000 steps of focusing. It works out to steps of .00123 of an inch. Far finer than my shaky old hands are able to do now. But the best part was being able to control the fine focusing with my computer, and never touching the equipment. I would imagine your NEMA 17 steppers have a better drive train in them as well. I think those are an industrial design.? Well done solution! |
Timothy Campbell
to navigate to use esc to dismiss