Guiding Graph: Page 3 - ZWO User Forum

Guiding Graph

w7ay

Byrdsfan1948 FYI the last two observing nights I had my ASIair either connected via a Cat 7 Ethernet cable to my home WiFi router, and my Tablet connected to the ASIair via wifi to my home network where the ASiair then shows up. This has proven to be a very strong and reliable connection that for me has totally eliminated the short WiFi range problem of the ASIair..........

Yep, all that should work well.

My own setup is a Mortar tri-pier and RainbowAstro mount that are left outdoors under a couple of dry bags when not in use (I only remove my main OTA and guide scope from the dual-saddle plate on my mount). At the base of the tri-pier is a waterproof box that includes an ASIAIR Pro and an eero mesh router. Effectively, that ASIAIR is directly connected to my home network. 12V feeds the box from the house.

For what its worth, the ASIAIR will connect directly to an iPad through a Lightning-to-Ethernet adapter (older iPads) or a USB-C-to-Ethernet adapter (newer iPads) by setting the network setup in iOS to use Ethernet instead of WiFi. Absolutely blazing speeds. I do not drive to remote locations, but if I did, directly connecting an iPad to ASIAIR would be my preference.

What I suppose still is a mystery to me however is if there is a software or camera problem why is it that so many others report no problems at all?

Well, lots of people probably fall into my category; we can get within a factor of 2 of PHD2 (with single star tracking) and while not ideal, produces acceptable star sizes, and we just leave it at that. The better mounts have less backlash (the RainbowAstro and Hobym harmonic drive mounts (both Korean) have virtually no backlash), and a small backlash might be what makes the difference.

You are definitely not alone, though. If you read the Facebook ASIAIR pages, you will find lots of people with a problem of mounts just taking off by themselves while autoguiding (and lost stars too, even when they are visible on the screen). And like spotting cockroaches, if there are a couple of people bothering to report a problem, there must be many more who don't, and may have given up on ASIAIR and went to use N.I.N.A., StellarMate or INDIGO Sky.

Many months ago, I had sent the ZWO folks a heads up that the DONUTS multi-star tracking was available in the open sourced INDIGO framework. DONUTS was published in professional circles at about the 2013 time frame I think -- the variance of "seeing" error halves each time you double the number of stars used. Now, PHD2 has its own multi-star tracker (under Beta), so ZWO lost the chance to get a leg up on PHD2. Instead, the tracking in ASIAIR appears to be a factor of 2 worse than single star PHD2; so there is now a factor of 4 in tracking performance between what you can get from PHD2 and what you can get from ASIAIR.

Chen

Byrdsfan1948

Hello Chen, Yes I do see a lot of guiding problems and comments on the various Facebook groups I have joined. Clearly postings describing problems involving guiding are far and away the most common and constant compliant.
I have to be very honest however the responses from the more experienced people there seem very superficial to me and essentially unhelpful. You, in the past week or so that we have been discussing this issue, have been far more helpful, and taught me more, by far.

I love your comment about the number of people complaining only being the tip of the iceberg. I totally agree! In my former working life, I was the SVP of Manufacturing and Engineering for the Bic Corp. Of course a large part of of non stop quest to improve our quality control, and product performance, came from customer feedback.
We held very regular, and very detailed meetings, where we closely examined each complaint even to the point of tear down analysis. It is critical to understand that if your producing 1 million lighters, or 3 million shavers and countless millions of pens a day, that a quality rate of 99.999 % acceptable quality, simply is not good enough.
When we talk zero defect, we mean zero defect!! So you might try to imagine level of sophistication that was needed to design and build, the kind of high speed assembly equipment with all the electronics and computerization control interfacing necessary to accomplish that, each and every day. Day in and day out!!!
But back to your comment....... We estimated that for each consumer complaint we got back, that there were about 1000 we never heard from.
Relating that here in the case of ZWO ,and this guiding problem. At this very forum site we can see how many comments are related to further product developments concerns and so few to this issue. Sadly it seems that ZWO seems somewhat obtuse to the fact that one of the most significant selling points of their product is failing miserably to consistently deliver to a great many of their customers as promised.
I am increasingly concerned that this is not a unique example...... I certainly understand why for example that they decided to move from a plastic case to a metal one to help dissipate the heat this little box develops. But in trying to solve one problem they created an entirely new and very significant problem for their customers to work around.
BTW the WiFi problem seems to be right up there with the guiding problems in the Facebook groups. Who at ZWO is in charge of their product development, and quality control? What in the world are they thinking of? They have a product that is a game changer, at a fantastic price, and it seems that they are almost dedicated to killing it rather than to resolve the existing issues that are causing new customers like me to start considering alternatives.
Look for right now, we don't need new features, just make what is supposed to work WORK!!!

I guess I am venting here. Venting because we at Bic always understood that one of the biggest problems when it came to customer complaints was not from the customers who took the time to complain. But from the ones who never did........... Because it was far easier for them to let one bad pen, lighter, or shaver, define their opinion of our quality and product performance and just buy their next pen etc from some other manufacturer!
Right now I'd be willing to come out of retirement for a few months if that might be helpful to get ZWO to focus on the job they seem to be ignoring.......................
Sorry as I said I believe I am starting to vent some frustration here :-). Al

w7ay

Byrdsfan1948 BTW the WiFi problem seems to be right up there with the guiding problems in the Facebook groups.

Except that the WiFi problem can be band aided by the user. Their guiding system, as a closed software system, is not.

I am not as [term for urinating] at them for engineering errors, and complete lack of regression testing as I am at them for not acknowledging the errors when they are reported. That is not a good sign. There still have not acknowledged that there is a WiFi flaw in every ASIAIR Pro that is shipped. What they don't seem to understand is that in the West, honesty counts much more than proficiency; it is how we separate great companies from good companies.

Notice from their release logs that they are calling outright bug fixes "optimizations." Just say "bug fix" and people will trust you more in the future.

The ASIAIR is indeed simple to use -- until you hit a road block (WiFi, autoguiding, polar alignment slew, power available in 12V ports, etc, etc). A technical person will be able to diagnose the problems right away; but most likely an advanced user is not using ASIAIR anyway. In the meantime, the target audience (novice users) are left begging for help for problems that are not even acknowledged. The novice thinks it is his or her own fault instead of the fault of the product. Because of the lack of feedback from ZWO, they have no idea if it is something they can learn to improve, or something that cannot be improved.

There is a point where "saving face" has to give way to proper engineering practices.

[\rant]

Chen

w7ay

Byrdsfan1948 Right now I'd be willing to come out of retirement for a few months if that might be helpful to get ZWO to focus on the job they seem to be ignoring.......................

If they ever take up your offer, tell them to focus on testing every feature before releasing it, and to fix all bugs before adding a single new feature. Perhaps you can be their "Deming." (Not sure if they even know who Ed Deming was.)

Chen

zuts

Hi, I also suffer from guiding issues, AZEQ6 mount, ASI 120 mm mini. I usually set my guide interval to between one and two seconds. The guiding fails when for some reason the PI seems to 'choke' and guiding fps drops from say 1 fps down to about 0.1 fps. This is clearly evident in the logs, which I sent off to ZWO support, but of course I never got a reply from them.

w7ay

zuts The guiding fails when for some reason the PI seems to 'choke' and guiding fps drops from say 1 fps down to about 0.1 fps.

Yep, I too notice that my FPS (reported in the PHD2 log) from the guide system stutters. I have already asked their developers (through direct email) to look into that a little while ago, but they swore up and down nothing has changed since v1.3.

ZWO really should take technical support seriously and answer all report like yours (hear that, Jiang xian sheng?) even if the answer is a simple, "we don't have a solution yet." Leaving a paying customer in limbo is simply not acceptable for any company.

Chen

Byrdsfan1948

Hey Chen and Zuts, Where would I find the fps ( guide camera ) log you are referring to? This on the surface sounds like what I am observing when my guide star suddenly fades away.

HAHA Chen Yes Edward Deming !! I actually met the man maybe 30 years ago now. It was during a period where we were top to bottom reinventing our approach to Quality Control and establishing different methods, essentially adopting his approach to continuous improvement to run our own continuous improvement programs. A lot of data, graphs, and 6 sigmas etc :-))
An interesting observation last night. I did get a few hours of unexpected clear skies so I quickly set up and tried again to see what if anything I could learn about this issue,
First of all in spite of one of my better PA's, and very close attention to balance, and level, I almost immediately ran into guiding problems. Essentially I could not even get the system to re calibrate on a star. To make a long story short(er) As a last resort I tried running the ASIair app from my Iphone 12, instead of my larger Samsung Tablet.
The interesting observation was that after doing that I was able to get some very acceptable guiding, as shown in the photo here. It was still not 100 % trouble free but far less trouble. I did have to restart the guiding once or twice for example and not all the guiding was as good as in this picture but all in all a far less frustrating experience.
I had made some other changes before switching from my tablet to my phone. I had changed the Calibration Step and RA and DEC duration to 1000ms from 2000ms but I have played with theses settings in both directions many times before without any improvements. My RA and DEC aggressiveness was set at 55 in both cases.......... But for some reason on the Iphone those changes seemed to react as you would expect them to, where on the tablet they do not. Of course this is just one experience over just a couple of hours so it probably means nothing, but certainly I will try this again the next clear night. I know on the surface it makes no sense but what does make sense here anyway? Al

w7ay

Byrdsfan1948 Where would I find the fps ( guide camera ) log you are referring to?

The log actually vanished for a short while around the v1.5.0 time frame (the current v1.5.x is a disaster), or somewhere around there. When I mentioned needing to see the log, ZWO told me it was right there, but when I told them to recheck, they found that indeed it wasn't :-). It is back now, in the released v1.5.1 or v1.5.3.

Look in your microSD card for a folder called Logs (it might be inside a folder called Images, or at the same level as Images; the memory in both my ASIAIR are cleared at the moment, so I am doing this by memory and my ASIAIR v1, which had been left unused after purchasing my two ASIAIR v2, is currently being used as a fixed "all sky camera" with no mount, and thus no PHD2 log).

Even better than constantly inserting and removing a microSD card, it is best access the files through the Raspberry Pi's Samba server -- I don't even remember when I last touched the microSD cards.

On macOS for example, you simply use the Finder's Go Menu and select "Connect to server" and connect to smb://192.168.x.xxx (whatever the IP address of your ASIAIR, and log in as guest (no password). You should see Disk and Udisk (if you have USB memory plugged in). In the Samba volume, you should see a folder named Images, and one named Logs (which could be inside the Images folder). Just look for documentation for accessing Samba file server on your own favorite desktop computer.

The PHD2 logs are named PHD2-Guidelog-<date and time>.txt.

The PHD2 log viewer is a good was to read the data:

https://openphdguiding.org/phd2-log-viewer/

Each line in the text file starts with an integer index, followed by a time stamp. The time stamp should be increasing at a constant delta, based on your guide camera exposure time (PHD2 uses that as the sampling period too). If it stutters... well, you know what happens to feedback loops when that happens; excrement flying all over the place :-).

Chen

w7ay

Byrdsfan1948 My RA and DEC aggressiveness was set at 55 in both cases.......... But for some reason on the Iphone those changes seemed to react as you would expect them to, where on the tablet they do not.

Al, see if you can get some more sampling (no, not to 6 sigma, we will all be pushing daisies by then :-) to see if this is consistent. And as they say, correlation does not imply causality. But if it is consistently so, ZWO might have a GUI problem with regards to aggressiveness values on Android. The loop has always behaved as expected when I tried adjusting aggressiveness, but I only use iOS.

By the way, you can also check the PHD2 log to see the aggressive setting on your Samsung run (or perform a new run, if that log has been scrubbed). You can check if the log catches the changes, and correctly. If not, then there is definitely a GUI problem. The PHD2 log viewer implementor had named the parameter "aggression" -- ahhh, the subtlety of the English language (my third language; but has turned half acceptably into my first language).

Chen

kvastronomer

I noticed this today on ZWO website. Maybe it will help.

Byrdsfan1948

Chen, I will certainly try to see if is a consistent pattern. Ahh yes the subtleties of the English language. To be clear about exactly what I meant. When I said that the "changes in aggressiveness reacted as expected............ " In both cases, when I try to change the numerical settings, they do change either up or down, ON THE SCREEN. However It seems on the Sansung tablet that those indicated changes do not result in making any difference with the guiding problem. On my Iphone it appears that they did. So if that is what you understood me as saying, then what I am understanding you are saying here, is that if this is a repeatable observation, perhaps a GUI issue exists with the Tablet, where the results shown on the user interface may not always be correctly translated into the actual expected commands and resulting changes. That is a very interesting thought since that to me suggests that the problem or at least some of it might exist outside that actual guiding software.
Also I should make it clear that I cannot at this point say with certainty that this observation is a consistent one. What I can say with certainty is that changes with the aggressiveness settings on my Tablet have never lead to a solution to the guiding problems once they start. I only bring this possibility up because last night I had for the first time the chance to make certain observations during the same imaging sessions using two different user interfaces.
Unfortunately it's snowing again so it maybe a few days before I can retest................... I wish I had a planetarium in my music studio where I could test out any experiments any time I wanted :-)))) Al

w7ay

Byrdsfan1948 So if that is what you understood me as saying, then what I am understanding you are saying here, is that if this is a repeatable observation, perhaps a GUI issue exists with the Tablet, where the results shown on the user interface may not always be correctly translated into the actual expected commands and resulting changes.

Yes, that is what I thought you meant.

The core PHD2 works pretty well and ZWO probably did not touched it. What they touched were things that are not in the core PHD2, like controlling the guide camera (that is why we cannot guide with QHY or Starlight cameras), the UI interface to PHD2 (that is why we can't control the critical MinMo parameter in PHD2), etc.

When you change the aggressiveness, give the loop a couple of seconds (at least 3x the guide camera exposure time) for it to catch up, before changing it again. The autoguider has tp use the new agressiveness to work on two new successive samples (exposures).

Chen

Byrdsfan1948

Thanks KVastromomer, Yes I have been aware of this for a few weeks now and have in fact have already downloaded this update to my Samsung Tablet but have been unable to find a program I can use to unzip the downloaded files and install them to try. Al

Byrdsfan1948

Hi Chen, Yes when I make any changes to the Aggressiveness settings I wait for over several minutes before I make any other changes. Unless, I have to just stop the guiding because it has gone completely off the rails, I will allow both the current main camera image I am taking, as well as at least the next one, to download I use those images ALONG with any trends I may start to see in the guiding graph to help me decide if there has been any impact on the guiding due to that change.

BTW along with the suggestion you make here looking for the change to "catch up" I also when examining the graph total error I do the same thing. Sometimes it can take quite a while, over a minute, before any improvements I may start to see in either the individual DEC or RA numbers to result in a positive ( meaning an improved ) Total error. But that is due to the nature of the mathematics involved.

Of course your comment about letting things "catch up" is my biggest problem when doing my PA's. Because of the lag in the image up load when doing a PA, my Italian genetic impatience, and my Type A personality, I am often making mount adjustments to an image that is not the result of my last adjustment........... Resulting of course in me just chasing that blue target circle all over the place........ It would be helpful if somehow we could tell how many images are in the cue to be yet upload before getting to the one that is reflective of our most recent change....... But of course at least I could resolve this minor problem with just a bit more patience :-))

The skies did clear last night, but between by time they did, and the fact that I decided it was a bit too icy out there after our latest snow storm, I let wisdom rule over valor, and decided to use common sense and resist temptation!!

Hopefully I'll get a better, and safer opportunity tonight. My goal for today however is to find whatever app I need to download on my Samsung Tablet to allow me to open and install that FW update for the 120mini......... Your comment here regarding how ZWO modified the non core camera setting with their version of PHD2 is just screaming at me saying: LOOK HERE DUMMY !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Al

w7ay

Byrdsfan1948 I am often making mount adjustments to an image that is not the result of my last adjustment...........

Aha. Turn off the auto refresh during polar alignment.

The auto refresh is open loop and not done in synchronism with your adjustments. Think of it as a feedback loop, with you, the human, in the middle.

What I do is simply refresh the plate solve manually, and then use the results to adjust the altitude and azimuth bolts (one at a time per plate solve, since any tilt with respect to the horizon will cause coupling -- i.e., technically, the rotation matrix has non-diagonal terms).

Your muscle memory will remember how much to tweak the bolts for each arc second deviation that is reported by polar alignment.

The millennials want this and that to be automated, which is fine if the plate solve is in sync with your adjustments. But they are not.

Chen

w7ay

Byrdsfan1948 Resulting of course in me just chasing that blue target circle all over the place........

Again, ignore the graphics completely (I can't emphasize enough how stupid that graphical interface is, with the autoscaling; I did not do any GUI work at Apple, however, ha ha). Adjust the bolts based on the numbers and the two green arrows on the upper right side of the screen.

The green arrow directions will be opposite of what is needed if your adjustment bolts are on "the other side" of the axes from you. But once you "calibrate" your adjustments, it is perfectly consistent for that mount in the future.

So... hit refresh, wait for new numbers to be reported. If altitude error is greater than azimuth error, work on that one first. Adjust the bolt based on the reported arrow and green arrow direction. Rinse and repeat. Do not adjust both alt and az bolt per plate solve refresh unless you are certain your azimuth axis is perfectly perpendicular to the horizon and the mount has no orthogonality error between alt and az axes.

Oh, if you have an economy mount, the polar alignment error will be large when you lock the alt and az axes. One way to reduce the problem is to partially tighten the locks, redo the plate solve and adjustments, then tighten a bit more, redo... until the alt and az are completely locked.

When you get frustrated enough, go out and buy a premium US "German mount," or a Takahashi or Vixen mount, or the RainbowAstro or Hobym. The Avalons from Italy are very good too, and they even have options for motorized alt and az adjustments.

Avalon's T-pods are probably the best in the industry and favored by portable hobbyists for their stability if they can afford it. We are trying to polar align to a few arc seconds, the tripod should be stable to that degree [sic], too. I use a William Optics Mortar tri-pier and pretty happy with it so far -- in fact, I do my fine altitude adjustments during polar alignment by pointing one of the legs to the North and using its nice leg leveler as my altitude adjustment (looong moment arm for its bolt thread -- I can easily adjust to one arc second). The Mortar's feet sit on top of 10mm thick aluminum plates and the plates sit on the concrete stepping stones from Home Depot.

Ciao,
Chen

Byrdsfan1948

Hi Chen Well DUH!!!!!!! I guess sometimes the obvious answer was just too obvious for me to observe. "Just turn off auto refresh!"........... I believe I should be able to give that a try next PA!!! :-)))

Actually you also touched very nicely on a few other details here. I do for the most part ignore the circle graphics and for the most part focus on the numbers....... However as you also point out, the adjustments are made horizontally and vertically. But due to the OTA orientation during the PA process the resulting changes in the X and Y directions become a trigonometric function of that orientation angle along the pointing axis of the OTA......
Your other comment is one I never considered and that is that the direction to adjust the AZ bolts as shown by the green arrows depends of which side of the mount your standing on when making those adjustments.
Very helpful comments Chen !!

I have found that the best way to zero in when making the final fine AZ adjustments is to do as you suggest. Once I get close I essentially gently tighten both bolts and then ever so slightly loosen up one side while just slightly, and I mean slightly, turning the other. That greatly limits the travel, while at the same time leaving the bolts somewhat tight. Once I am within the acceptable area I then equally snug down both adjusting bolts, and then slightly pre load one bolt depending in the direction needed for the final adjustment and then slightly loosen up the other side. In essence that eliminates a good deal of the problem of movement when tightening. However the bolts used have threads that are simply way too course for any real precision adjustments. So bottom line is anything better than 0.30 arc seconds is more luck than skill, and certainly not reliably repeatable.

The Alt Adjustment is more problematic because only one adjusting bolt is involved. There is where I probably introduce the biggest component of any PA inaccuracy. I do snug down the clamping bolts but leave them loose enough to allow some final adjustment. But when I do then finally tighten them that does introduce some final movement and inaccuracy.
It is a bit disappointing that a $2000 mount that has some very decent precision designed into it's drive system uses a crude and very sloppy, poorly designed system ( if one could call this a system ) for PA adjustments. But compared to the guiding problem this is small potatoes.

I suppose all is not lost however. When I purchased this mount I knew very little about what to look for in a really quality mount. All in all I am very satisfied with it and even with the draw backs we are discussing here it can still track very accurately with my set up for my current purposes..... What I have now I can see serving me very well for a very long time.

However my wife and I do own a second home in Jackson Hole Wyoming within the borders of Grand Teton National Park. As you might image the skies there are very dark. I can easily see this entire set up making a one way the trip out West latter this year, and that giving me the opportunity for a serious upgrade here....... Hopefully by then I will know a lot more about the really important details !!! :-) Al

w7ay

Byrdsfan1948 However my wife and I do own a second home in Jackson Hole Wyoming within the borders of Grand Teton National Park. As you might image the skies there are very dark.

If, at your age, you can still carry heavy loads, you owe yourself a 10 Micron mount. Once you see and use one, you will know that the Chinese mounts are pure trash. (With an ME's eye, too :-). The waiting list is long, so you might receive one when we can finally travel again :-).

If you have a friend who has a RainbowAstro, you should see the machining (mount body machine milled out of a solid block of aluminum. Heck, each mount is first anodized and then laser etched with its serial number. It is not an especially expensive mount either (at least by California engineers' standards :-).

I have a small stature and could not handle weight. For years, I had been depending on the Takahashi EM-11, the smallest of the Takahashi mounts (not counting the lightweight stuff like the Teegul that are not meant for astroimaging).

I would need a lot of help from Archimedes (Mr. "give me a fulcrum and I will move the mass of the earth") to handle even the smallest 10 Micron mount :-).

As I got older, even the EM-11 became too heavy for me, so I moved to the RainbowAstro, which is not only much lighter, does not require a counterweight (more weights..., it can handle a bigger payload than the EM-11 to boot). I have two of them in case I want to set up two OTA simultaneously, and also with one as a spare since I cannot see taking the EM-11 out to use again in case the one and only RainbowAstro fails. But the tracking precision is nowhere close to a premium US mount.

Chen

Byrdsfan1948

Hello Chen, A quick look at the 10 Micron Mount ruled that out ! No way will I pay more for a mount than a new guitar :-) But seriously it does seem like over kill for my needs........... A quick look at the RainbowAstro ( 135 ) appears to be very interesting....... I have book marked that information and will look it over more closely latter. I assume your opinion is that it is in a different ( improved ) quality class than the more typical ones out there?

Interesting experience last night. It was still cloud covered around sunset so I had written off the night, grabbed a glass of wine, and settled down to watch Jeopardy. During the break before Double Jeopardy I took a quick look outside and found Orion clearly visible. The clouds around that part of the sky had cleared out fairly well. So on a last minute whim, I quickly set up my scope at the corner of my back patio. I have 3 spots marked there to locate my tripod legs to make PA quicker each night. I simply set the legs on those spots. I didn't check for balance, and I didn't even bother doing a PA. I connected the ASIair, and then directed the mount to slew to the Orion Nebula. BINGO!! It came up exactly centered ......... I then quickly connected my Ethernet cable from the ASIair to my home router and was in business in less than 10 minutes. I had enough time to catch the end of Double Jeopardy, and Final Jeopardy.

What was very interesting was that I ended up with about an hour of usable time before the clouds ended the night.   I had no intentions of any meaningful photography.  I simply let the preview view keep reloading as I watched the guiding.     I used both my Tablet as and my Iphone.  In both cases the guiding was far more stable than any recent night. Even with the high clouds that were passing by, the guide star was only lost once, and even then quickly it was then found and guiding restarted.      I did re-calibrate once at my first target but that was it.   I guided on three separate targets.  M-42, Betelgeuse, ( which was doing a good imitation of Mars :-) ) and M-35.   All three targets of course are within the same general area of the sky that was fairly cloud free for the hour.   Because of that I didn't re calibrate when I moved from target to target.  
First of all I am impressed that quickly setting up on those three dots on my patio, with no PA, was good enough for the GO TO function both in the ASiair, as well has my hand controller to work as well as they did.  Both every bit as good as if I had done a good PA.  More importantly was the guiding virtually always under 1.0 total error in very unstable seeing conditions.    Of course we are talking only an hour here but usually by then I am well past the frustration point!

I was at least able to open up those zipped files for the FW upgrade for the guide 120mini guide camera on both my tablet as well as Iphone........... BUT I am unsure in both cases if I was actually successful in installing the upgrade. Other than that the only other thing I can think of, is that by the end of the previous night I had followed one of your suggestions with the Aggressiveness settings. So last night in both cases they were set at 55 as I had left them last session. All in all very interesting but of course hardly conclusive. If I can get a break in the clouds again tonight even if only like last night I'll wash, rinse, and repeat! Al

w7ay

Byrdsfan1948 I assume your opinion is that it is in a different ( improved ) quality class than the more typical ones out there?

The 10 Microns are, but the RainbowAstro RST135 is not.

There is a price premium on the RainbowAstro, not because of precision (although the built quality is top notch) but because of the portability (very light weight and requires no counterweight). In my case, it fits my bill perfectly because I primarily focus on weight vs payload capacity.

The harmonic drive is both a plus and a minus (the same applies to the Hobym). A plus because of the torque available negates the need of any counterweight, and a minus is that a harmonic drive has the highest periodic error in the market, and absolutely requires guiding. Unless portability is important to you, you are better off with a Losmandy G11 (about the same price class, but much better precision) or the 10Micron 1000. Heck, my two RST-135 together cost me as much as a 10Micron 1000GM, and I would have picked the latter if not for the fact that it is so heavy I would need to disassemble it into separate pieces each night.

Chen

w7ay

Byrdsfan1948 I had enough time to catch the end of Double Jeopardy, and Final Jeopardy.

OT: not quite the same without Trebek :-(.

One of the things that I have found is that the best equipment is useless unless you can quickly set it up and tear it down; just like what you did.

My tri-pier and RST-135 (with a dual saddle plate) are permanently outdoors. The ASIAIR, power hub and error mesh router are in a waterproof box that is strapped to the pier. And I have two 12V lines running from the house to the mount (the RST-135 back drives when power is lost, so I have a DC UPS running an independent 12V line to it).

Because the snow in the next few days is expected to be over a foot, I brought the box back indoors just in case.

The RainbowAstro has no greese to dry out, so the mount is outdoors all the time, under two layers of dry bags when I am not using it.

If I am careful when mounting and dismounting the OTA and guide scope from their dovetail clamps, I have gotten 10-20 arc seconds type polar alignment from night to night. Even when not taking care, I am usually within 1 arc minute (the limit where I don't need to polar realign). But any polar alignment is an exercise that lasts no more than 2 minutes to get less than 10 arc seconds.

Chen

Byrdsfan1948

Chen I have no idea what is going on there with that slider but slide it to the right to read what is written there? As if guiding isn't already a big enough problem to deal with :-) Al

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