PME Commissioned ... finally!!!

[marc4darkskies]

After waiting an eternity for the clouds to break I finally managed to finish commissioning my new PME.

Raw uncorrected PE of this mount is only +-0.8 arcsec!! I repeated the measurement several times to make sure too! The corrected PE seems to be lost in seeing noise but PrecisionPEC suggests +-0.5 arcsec.

I also did a 300 star TPoint model. This will get me to within 10 arcsecs RMS of any target using TheSkyX (which I can't use in anger yet because my Laptop is too old and slow :sadeyes:) or 13 arcsec in TheSky6 (after mimicking as much as I could from TheSkyX's model). Polar alignment is close enough!

See the screen grabs at the bottom of: http://www.pbase.com/gailmarc/paramount_me

Now I can get back to imaging!! Woo Hoooooo! :party:

Cheers, Marcus

[pmrid]

Congrats Marcus. They look the goods don't they. I can't wait 'til my PMX arrives. Which leads me to ask a question. When I mounted my Titan, I had to shorten my pier by about 400mm so I wasn't standing on stepladders. Now at 700mm, it is just about right for my short little legs.
Did the PMA require a similar 'shortening' of your pier?
Peter

[marc4darkskies]

No. As it turned out, my 1.06m (42 inch) pier was about the right height. The PME was very close to the same height as my old EM-400. In fact the setup is closer to the ideal height for my dome.

Yeah, that PMX is a good buy for sure - you'll love it! Make sure you post plenty of pictures when you get it!

[strongmanmike]

That uncorrected PE sounds very good....nearly as good as my NJP :P

In reality as an imager, I imagine you will rarely need that level of pointing accuracy..? but good to have when you do.

Top stuff :thumbsup:

[g__day]

Very, very impressive stats!

[marc4darkskies]

True enough ... but if you've got it, flaunt it!! :D Besides, it brings a smile to your face when you can slew to the opposite side of the meridian and have your target smack bang in the middle of the FOV :eyepop:.

Seriously though, anything that removes just a little bit of fiddling from your workflow (ie (re)acquiring and centering your target from night to night) is a bonus!

Cheers, Marcus

[gregbradley]

Wow, you really got your mount setup beautifully Marcus.

I tried using PemPro demo to fit a PEC. I got a PEC curve but its upload to PME option did not work as it said to do. Or at least I don't think it did.

How did you find Precision PEC? Pempro claims to be more accurate because of a few things it takes into account. But of course if you can't upload it when done it isn't is it?

How did you do your polar alignment - CCD drift alignment? Or did you use T-Point and follow its recommendations?

I improved mine recently and am back to round stars. I was getting slightly eggy stars for a while.

One thing that helped was I entered the time more precisely using my iphone's clock.

And using a 15 point T-point polar alignment recommendation.

I think I need to do a 50 point model and see what the recommendation is to tweak it a bit more. Automapper may be just the tool. Is it hard to set up?

Greg.

[marc4darkskies]

PrecisionPEC was simple and uploaded the PEC curve to the PME without issue. Given it's such a small PE I was surprised it fitted a curve so well.

I used a smaller 30 star TPoint model to do the polar alignment. Your PA would have to be pretty bad to yield out of round stars! What guiding software were you using?

Yes, accurate time on your PC is critical. Download NMEA time (small cost) to connect to an internet time server. It will update your clock when you start up and then you can set it to update regurlarly - I set mine to update every hour.

AutomapperII is very easy to use ... and it's free!

Cheers, Marcus

[batema]

Hi Marcus,

If you want conversation then please don't invite me to look at your set up as I would happily sit there for hours just staring and dreaming at that amazing looking set up. You must be thrilled. Well done and thanks for all the photos.

Mark

[[1ponders]]

I can really appreciate this photo Marcus, wholeheartedly and completely
http://www.pbase.com/gailmarc/image/132296221
http://www.iceinspace.com.au/forum/attachment_browse.php?a=87502

what a beautiful setup.

[gregbradley]

Hi Marcus,

No I disagree, PA can be close and still get eggy stars at 3 metres focal length. I have drift aligned it at times and gotten it very good and still get slightly eggy stars in 10 min subs. Mind you they are only medium eggy but not good enough.

Everything is easier at 1 metre focal length. At 3 metres round stars are a bit harder to achieve even with the PME. It needs to be setup just right but of course it is capable of it. I had it setup pretty nicely and I must have bumped into the scope a few times (its at one of those heights!) and also I installed an autodither plugin in CCDsoft and that affected the autoguider and took me ages to find out why things were going pear shaped with guiding.

I redid PA and it is close at the moment. I also accidentally erased the existing PEC curve and then tried Pempro. It created a nice curve but I couldn't get it to upload. I suppose that is a question for the Pempro group. It seems rather fiddly as a program and has lots of steps. But it may be the way to go and just go through the learning curve.

Guiding software is CCDsoft. I use a MMOAG with an ST402. It is a good setup although the connection between the 402 and the MMOAG is weak and a possible source of flexure. I may get a proper screw connector. I was also advised a simple parfocal ring on the 402 nosepiece helps.

You need Pinpoint as well as Precision PE. I may get those and go through a similar routine you have. It would be worth it long term.

Also now you have a large Tpoint model you can activate Protrack and get even better tracking.

My mount is also about +/- .8-1 arc second PE. I saw this a few times as I recorded PEC. The scale was +/-1.5 arc sec and the graph didn't go more than about 1/2 way to the limit.

The PME seems to be pretty tolerant of balance being such a beefy mount but I have seen errors from a lack of balance at times. It can be balanced horizontally and be out of balance at 30 degrees.

You must have wireless internet in your observatory? I don't have an internet connection in my observatory. I have a wireless modem but it didn't extend that far. Time off the iphone I imagine would be accurate to the nearest second. Updating it every time may be a good idea. I'll have to check to see if the computer's clock goes off over time. My time was off by about a minute when I updated it off the phone. It seemed to make a noticeable difference.

Greg.

[marc4darkskies]

Cheers Mark. Right now all I can do is stare at it ... the weather won't let me do anything else :sadeyes: :mad2:




Ahhh ... kindred spirits! :lol:

[OzRob]

Did you find the special instructions to upload the curve in the help file? If you go the the help file and look under PEC>User's Guide>Program Mount there is a link to the instructions for the PME.

[marc4darkskies]

Fair nuff.


That plugin has never worked for me but I haven't tried it in a long time.



Hmmm, yes, a few SECONDs can make a noticeable difference! I've just recently replaced my wireless connection with an ethernet cable. Wireless is a PITA - frequent dropouts at a mere 20m! Get yourself a GPS unit that has a serial port and outputs NMEA messages. NMEATime will happily decode these - no need for the internet.

[gregbradley]

Good idea. I have a handheld GPS unit. Not sure what output it has. I'll check it out.

You have to have Pinpoint for the automapper to work right?

Did you use the automapper to get your 30 point model? It seems to be the way to go otherwise it is time consuming.

I could probably install an ethernet cable. I could run it under the house and then across the final 12 metres in a shallow trench.
It'd be a total of about 30 metres though.

Thanks,

Greg.

[marc4darkskies]

No. AutomapperII works with CCDSoft and TheSky6. Funny thing was my dome battery ran out of juice before I finished the 300 point model! :mad2: I had to jury rig a cable from my UPS to finish. I have TODAY removed the dome battery and hooked the dome directly to my main power supply!!

My ethernet cable is 33 meters long (more than I need but I don't have the tools to make a custom length cable). I've had no issues so far.

Cheers, Marcus

[Doomsayer]

If you use boosted gain antennas for your wireless base at the house and at the receptor in your obesrvatory that helps a lot with wireless reliability. I use TheSky6, the 'old' version of Tpoint, CCDsoft, FocusMax and Pinpoint for my PME rig along with CCDAP for automation. Lately I have reverted to drift aligning the PME, but still use Tpoint for goto modelling. As others have recommended if you are using CCDsoft or Maixm, plus Pinoint for platesolving, the freeware AAG Tpoint Mapper is also excellent for mapping stars for automated Tpoint modelling. I have stuck with CCDsoft as its 'direct guide' mode allows direct control of the mount via the serial connection rather than a guider cable.

Greg, I was suffering from eggy stars at times at 2.3m FL using a MMOAG and remote guide head with my STL6303. What sort of errors is CCDsoft reporting when guiding? I suspect a lot of the time I was chasing seeing if conditions were a bit turbulent. Getting the min/max move settings just right can be tricky as the PME is capable of such fine moves. An AOL is on my shopping list for that reason.

I suspect I may have polluted the PEC in the PME at one time. You have to be careful when using PrecisionPEC as it can allow you to append a new curve to an old one already stored in your system - clearing any older PEC data on your PC before doing a PE run is essential. I haven't had trouble with uploading a PE curve to the PME so far - I still use a DB9 serial cable connection rather than the USB connection - I am still running XP Pro so serial is very reliable.

I am contemplating moving my PME to a remote site to get away from the coastal cloud and genrally ordinary seeing. We'll see.

guy

[gregbradley]

Accurate drift aligning is hard to beat because it is the actual thing rather than an estimation of the thing (with models etc).
Like in building there is the object and then there is the measurements of where the object should be. Not necessarily the same at all!

Try putting in the exact time. Check your long/lat/altitude and make sure that is exact. Do you callibrate your guider often?
Is it square to the scope?

When I accidentally erased my PEC curve guiding was worse. I just recorded a PEC using the Sky 6 and it looked like the original
(much like a sine wave and gentle not heavy) and that improved things. Check your balance especially at the angle you are most likely to image at. If your setup is top heavy that will shift balance as you change angle. Make sure your mount is level and I take it eveything is stable.

You might try using 1x1 binning on your remote guide head and a brighter guide star if you can find one. I found if I could use 1x1 it got better results than 2x2.

I tried to load Automapper and it came up with an error message saying Pinpoint was not detected and to load it first.

There is an update to Automapper so perhaps I need that but I think I need Automapper in first for the update to work.

My guiding is set to 4 second exposure times. I set min move to .01 and max to .5. If you get an error bigger than .5 its got to be PE or seeing or bad polar alignment. Firstly I use 2x2 binning on the ST402. I pick a star that is reasinably bright but also quite tight looking. I don't usually pick a fat star. I get quite a large difference in guiding errors between guide stars. A tightly focused brightish small star is the go and I use subframing to frame it but not too small so the guider can reacquire the star if cloud interrupts.

I see errors that vary as the seeing and PE go through their cycle but it would look like this:

.1, .2, .4, .28,.5, .05, .4, .66 so a range between high of about 1 and a low of about .05, average would be about .25 at a guess perhaps higher. When the scope is pointing closer to the zenith the guiding errors are noticeably smaller.

I have found this combo callibrates very quickly. In fact its one thing I like about the PME, it takes about 30 seconds to callibrate the autoguider and it almost never fails compared to hell in the past with other setups. So I tend to callibrate more often now and that helps.
I also make sure the 402 is square to the scope as it seems to be knocked out of whack easily.

I think Marcus's approach is good, getting a fairly large model and using its recommendations. The problem I had was I drift aligned using the camera and then did a 10 point T-point model and I followed its directions and it made the guiding worse. So not a large enough model, not accurate enough time would be the cause I assume.

I'd like to a get a big Tpoint model not so much for accurate go-tos as I get close enough to find things but to use ProTrack to gain an extra edge in autoguiding.

With the MMOAG and ST402 I find the camera is not stable in the eyepiece holder of the MMOAG. It can rock. So I adjust it so the stars are round rather than eggy which means it is tilting.

I am going to buy a cheap parfocal ring and attach it to help find focus easily and stabilise the 402 in the eyepiece holder more.

Greg.

[Doomsayer]

Hi Greg
Accurate time is automatic for me since theSky etc draws time from the atomic clock based time servers on the internet - GPS satellites work just as well,
Sounds like your CCDsoft guide errors are similar to mine in their characteristics. I use around 4-5 second exposures plus I find that binning 2x2 helps when seeing is poor. Last time I tested the system the eggy stars had subsided - it seems so rare that I get clear sky to test it, so I can't make any conclusion based on regular experience as yet. I find with calibration that having the star centred and isolated from other stars which might interfere is the main thing.

I always run my PME with a minimum of 60 or so stars mapped either side of the meridian using AAG Tpoint Mapper once I'm satisfied with polar alignment. With only 15 points or less mapped it's actuially difficult to draw accurate conclusions about your model. You need at least 25 or 30 points to get a handle on pointing and alignment with Tpoint in my experience over the last few years. I have done 250+ Tpoint models before, but since I use autoguiding, Protrack is perhaps not so essential. I also suspect my pier creeps a bit with the seasons so redoing a 250+ Tpoint model regularly is not attractive.

I don't seem to have much problem with balance - I regularly check this.
I only run the one OTA and a camera so I guess there's no issue.

I really like the MMOAG but as you say the guider connection can be prone to some tilt. I use am ST402 for autoguiding my EM200 with an E-finder - works really well, assuming the RJ12 connections are behaving. I used to use the ST402 on the MMOAG before I got the RGH so I know what your are talking about.

Pinpoint really is worth the expense - a minor cost in my opinion - plate solving allows so many powerful tasks to be done very accurately and easiily with your mount, scope and camera.

Marcus seems to be well on track - so I'm sure we'll be seeing some outputs soon if the weather behaves.
guy

[gregbradley]

Hi Guy,

I think with all this rainy weather it is entirely possible the slab a mount is mounted on could possibly shift.
In my case I haven't noticed that. My slab is 1000mm deep and 850mm square with lots of steel in it and must weigh
a lot.

My observatory needs a bit of repair already as the wall has bowed slightly making the roll off roof system a bit unstable. I think that is a result of the 40C days and some rain etc plus a bit of sag over time.

Greg.

[rogerg]

Congrats on getting it Running so well Marcus :thumbsup: 1 month on (about 6 nights I think) I'm still doing calibration runs with mine :whistle: . Checking out the PE again tonight. Then new mapping run after that (perhaps not tonight).

[marc4darkskies]

Thanks Roger! It's worth spending time tinkering - you gain familiarity (that's my excuse anyway :)). I'd have done more too if these friggin clouds would go away for more than a night or two. I did notice N-S drift the other night so I may lower the altitude a twitch and re-model (after I get some imaging done!). Creating models is a cinch anyway. With the PME and no dangling cables I'm now comfortable walking away and letting the mount, camera and software do it's thing.

[gregbradley]

That's odd, your model says your aligment is perfect yet there is some drift.

That's what I was finding to some degree. The model albeit with much smaller numbers of points was giving worse results than the drift alignment achieved.

Greg.

[marc4darkskies]

I have two models actually. I did the original model in TheSky6 and then imported that data into TheSkyX to use the "Supermodel" function (the screen grab on my web site). I then mimicked the TSX supermodel in TS6 as best I could and THAT model says I'm at +123" elevation. The drift was fairly small too - about 7-8 arcsecs over 25 mins - easily guided out. If anything it is a small tweak of less than 1 arcmin that I need. Interestingly, both models agree on azimuth error. If the clouds would go away I could tinker some more but it's worth remembering too that it can be a diminishing returns argument to tinker too much. I think it's worth one more iteration though.

[gregbradley]

So the Sky X has some new functions over the Sky 6. Do you think it is worth the upgrade?

There can be a point of diminishing returns and also starting to go backwards but I am sure you know that.

It looks clear this afternoon, maybe tonight. The moon doesn't rise until 2am.

Greg.

[Bassnut]

The Sky X requires another Pinpoint version (more money), Id say the old Sky6 is fine for the obs, thats what I do, Sky X is great for planning imaging runs indoors if like me, you were to be sucked into buying it.

You need to get Automapper running Greg its a dream. I found a decent map run gave polar alignment feedback that allowed me to get within single digit arc seconds within a few tweaks.

[rogerg]

Others would differ, but while enjoying some usability features of TSX I have uninstalled it due to several extreme frustrations and some problems with it linking to CCDSoft. I persevered with it for 2 months but the clincher was not being able to have both it and TS6 installed at the same time without problems. I don't think most have the problems I have had.

[Bassnut]

I wouldnt, stick with Sky 6.

[gregbradley]

Thanks for the feedback about The SkyX. I'll leave it alone.

I downloaded Automapper II. Have to work out how to use it now.

Do you just click on a bunch of targets on the Sky 6 and it goes to and plate solves?

Greg.

[rogerg]

I find the easiest way to use AutoMapperII is to have it generate the list of points and define the horizon (exclusion area) in it's little limits editor. A small amount of practice and its very easy to have it do a 200 point mapping run, even with my tiny ST7 where a lot of plate solves fall due to small FOV.

[marc4darkskies]

Yep AutomapperII is nice for sure. A large mapping run is a piece of cake (unless your dome battery goes flat after about the 230th slew! :mad2:)

And don't be too hasty dismissing TheSkyX Greg. I've gone through the entire setup and almost the whole shakedown procedure. TSX integrates well with CCDSoft (latest version ...206). It integrated with Automadome and CCDAP nicely as well - no hiccups at all. I have tested plate solves and dome slews & slaving etc only to find out that my nearly 6 year old laptop is just too old to handle the CPU load with everything running. TSX utilises multi core processors so a new laptop is coming soon!! :D I have reverted to TS6 only because of my old laptop. I am actually writing a review of my experience with TSX and will complete it once my hardware is up to date.

You do not need to buy Pinpoint if you go TSX. The platesolves I did from CCDSoft were at least as accurate (and probably better) than TS6 with the USNO-A2.0 catalogue (once I downloaded and optimised the UCAC3 catalogue that is - for free).

IMO, TSX is worth checking out if you have a reasonably up to date PC! It is much more stable now than it was 6 months ago!!! The new interface alone is very slick too.

Cheers, Marcus

[gregbradley]

Thanks for the data Marcus. So to use the Sky V6 and Automapper 2 I need to download that database?

I use an i7 laptop 64 bit Win 7 with 8gb ram. Its an awesome machine and made processing 16803 images easy. A 1x1 16803 file is 32.4mb so it takes some processing power. With CCDstack 2 I can open as many 1x1 images as I have (haven't had a memory problem yet whereas it was common with a Core Duo 2 and 3 gb ram and Vista or XP).

I did a Precision PEC run last night. The resulting curve was quite small. How was yours? I also did a Polar alignment run with Pempro's polar alignment wizard which seemed reasonably good.

Greg.

[marc4darkskies]

No, you don't need another database to use AutomapperII. However, using the USNO-A2.0 catalogue (in TS6) improves the chances of a plate solve succeeding in areas of sky low in stars (ie away from the galactic equator). If you want it I have it on DVD somewhere.

That laptop of yours would run TSX without issue IMO.

My PE after correction appears to be a sin surve around +- 0.5 arcsec. I expected better.

[gregbradley]

Thanks Marcus.

Nice low PE result there. It is in reality at the upper end of what an amateur mount does don't you think?

Greg.

[rogerg]

Marcus & Greg (& other PME users),

How good is your poining accuracy after power-down and power-up between nights?

I'm finding with my current model it is off by about 180 arc seconds (consistently - across whole sky). With a previous model it was only off by about 30 arc seconds, but I did probably only try it a couple of times back then.

From what I understand I shouldn't need to do a shot mapping run and also should not sync. Yet at the start of a night I need to some how tell it "tonight, you're 180 arc seconds off - move north 180 arc sec and you'll be right for the night!" - exactly a sync.

Wondering what others find.

Thanks,
Roger.

[gregbradley]

I haven't really made a big model yet. The biggest has been about 20 points or less. It was pointing fairly accurately after a couple of points. Object about 1/8th away from centre of the screen image.

I don't see it vary from night to night. I thought that did not change once you powered down and powered up.

I find go-tos are usually an indication of PA error mostly. How good is your polar alignment?

I found drift aligning using the CCD every night for 30 minutes and tweaking it slightly to improve it a bit more over several nights paid dividends.

Greg.

[rogerg]

PA is pretty good, the rate of drift is about 0.2 arc seconds/minute, so it's many minutes before it's noticeable. TPoint is esimating it in the range of 0.3' - 0.5' from the pole in each direction.

Go To accuracy per se is very good - the offset is repeatable, an offset for all goto's. For example the first and all objects will be off by the same amount and direction as every other subsequent object. I can move anywhere in the sky and have the object centered almost exactly where the last object was on the chip (within about 10 pixels of the last object).

I'm only just starting to learn the stuff I need to in order to get this working smoothly, so think I'll work at refining things like the initial synchronise, pc clock, more points in the TPoint model (currently 120) and so on.

[gregbradley]

How do mean work on the initial synchronise? The first star you synch to?

How stable is your pier? Is it possible it shifted very slightly or perhaps you bumped your scope?

Sounds like you've got it working pretty nice.

With such a large Tpoint model have you activated protrack?

It may improve things a tad more. I just did a fresh PEC using Precision PEC and checked the polar alignment I did using Pempro (it seemed pretty perfect) and I am getting noticeably improved autoguiding. Quite low errors. Yeah!

Greg.

Greg.

[rogerg]

I only ever synchronise before doing a TPoint mapping run, never once I've got a good mapping run, so here I'm refering to the initial synchronisation when for all intensive purposes the mount is new out of the box.



I very much doubt that's a possibility. That's the kind of thing which is modeled out by TPoint, there's no reason I can think that the pier would move differently during the day than at night (if it moves at all) (for example being knocked).



overall yeah, I'm quite happy with it, certainly on the night I do a good TPoint mapping run things are as perfect as could be expected. Just a few niggling things to sort out. :)



I'd call 120 pionts moddest. Large, and sufficient for ProTrack to work well is 250+ from my reading and advice from others. I do have ProTrack enabled and it works well even with my 120 points for goto, but I haven't enabled tracking adjustments in ProTrack except for one test, as I'm quite sure I need that 250+ points for that to function well. 250 isn't a problem, I just haven't had a spare night to do it, or been sure enough I'll keep the model for several nights - I'm still finding new thinngs to try and so throwing away models frequently. :)

Looking at it now I think my attempt at a Short Mapping Run last night has messed up my model :rolleyes: so need to do a new one I think, maybe. oh well, lots to learn.

[gregbradley]

I tried activating Protrack the other night after creating a 17 point T-point model manually (automapper II was not able to identify locations, I installed a bigger catalogue and need to read the manual which is hard to find).

I found it worsened autoguiding a LOT. So you must be right it needs to be a large T-point model before worrying about Protrack.

Getting time precise, getting lat/long precise, getting Polar alignment precise and getting PEC well mapped are far more beneficial.

I got a very accurate Polar Alignment using PemPro's polar alignment wizard. It worked so well I think I will buy the program just for that feature. It would be awesomely helpful if you setup and broke down your setup each time. It makes CCD drift alignment a lot faster to get a lot more accurately. You get that part right and then it has a final small adjustment to get it even closer after that. Very nice.
After using it for about 30 minutes T-point after 17 mappings is saying my PA is off by only about .8 of an adjustment tick in both axes
ad my gotos are very very close to being centred on the CCD.

PemPro claims it is supposed to be a bit more accurate than Precision PEC because it takes into account if your camera is not completely square whereas Precision PEC just tells you to get your camera square.

Greg.

[Bassnut]

Just a correction. I use AAG Tpoint mapper (http://www.aagware.eu/) (free), not automapper 2, which I understand is not as userfriendly.

[gregbradley]

Thanks Fred that's helpful.

Greg.

[frolinmod]

I love my Paramount ME.

I've heard that the first production run of the MX has already completely sold out and some people will have to wait for the second production run. Amazing.

Why aren't you guys using the built-in T-point auto-mapper in TheSkyX? It works quite well in my experience.

I don't have a permanent observatory. The horizons in my backyard are very bad! I envy you guys with permanent observatories. I have to set up on an Astro-Physics portable pier (or Rob Miller tripod if the ground is very unlevel), even when in my own backyard. I car camp with my ME.

The PE on this mount is so good it's almost not worth bothering programming the PEC. But I did anyway. I used CCDsoft to collect the data and the built-in PEC curve fitting in TheSkyX.

I find polar alignment via T-point to be quicker and easier than drift alignment. I do three or four freshly synced 25 to 30-point automated runs, tweaking the knobs as directed after each run, then do a 150-200 point run for good pointing (~10 arc-seconds RMS with the supermodel). I like being able to kick back in my lounge chair after dusk while the mount does all the real work. The pointing really is 10-arc seconds too. Objects land right on CCDsoft's cross-hair box in the center of the CCD image. This is with a C-14 EdgeHd operating at FL=3911mm (almost four meters) with the mirror lock knobs engaged. I use a TCF-Si for focusing. I sure do like that new t-point supermodel feature!

When you're doing automated T-point mapping runs, you might as well bin 3x3. It's faster and it won't hurt your pointing accuracy one iota. I actually bin 4x4 with the QSI-583wsg.

In my experience you can't use ProTrack effectively without a good model mapping a large number of points. About 150 or more seems to work well for me.

The pointing does not change with power cycling. It takes an equipment change to affect the pointing. Minor equipment changes you should do a short mapping run (at least six points with some on each side of the meridian and at least two at high declinations) to maintain pointing accuracy. Major equipment changes you should probably do another full pointing run.

Because I usually don't have Internet access (and no cell phone service either) where I set up, I use a GPS receiver with 1PPS as a stratum-1 time source in NTP. This works extraordinarily well.

[gregbradley]

That's a good writeup. So obviously you'd recommend the SkyX. A lot of those add-on programs must be included in it.

I finally got to read the Automapper II online documentation so I can set it up to work.

Hopefully it will work next time I use it.

Yes the PME is a nice piece of equipment. The MX on paper sounds as good if not better.

Greg.

[Moon]

Ernie
If your have a picture of that, I'd love to see it. Sounds like a lot of fun.
James

[marc4darkskies]

I'll be using TSX when I get a new laptop - hopefully in a couple of weeks. I'll finish my review of TSX when it's all up & working. In the meantime AutomapperII is a piece of cake to use with TS6 & CCDSoft.

[Bassnut]

Ummm, because you have then have to buy a special Tpoint version all over again :P. free AAG Tpoint mapper, standard Tpoint most already have and Sky pro does just fine without all the upgrade gouging.

[marc4darkskies]

Why do you keep saying that Fred? TSX does not need Pinpoint. It plate solves just fine and, anecdotally, more accurately that TS6. Is it a gouge? Naaah ... just spend $15k on a new PME and it's free!! :lol:

[frolinmod]

I'll be packing up the car and going up into the local mountains later this month. I'll take some pictures then. In the mean time, this one will have to do:

http://members.cox.net/nairobi/IMG_0346-C1.jpg

[frolinmod]

None of TheSky6, TheSkyX, nor CCDsoft use pinpoint. Software Bisque use their own plate solver inside TheSky which in my experience works well.

In my opinion, when working with Software Bisque software, it's best to purchase their Universal Subscription.

And yes, I do wish software wasn't so expensive. That's why I haven't purchased Maxim DL or Adobe Photoshop. Prices are astronomical.

[Moon]

Sounds like fun (with some heavy lifting thrown in for good measure)


I've always been a fan of drift aligning, but after thinking about it some more, I don't think it's as good as a proper tpoint model to give you your necessary adjustments.

I did a test recently and it seemed like I was adjusting the polar alignment to take account of tube flex, and in the process tpoint reported the polar alignment was getting worse. If that's true, I would expect the mount to perform well only in that part of the sky, but terrible elsewhere. Whereas in tpoint, the tube flex term can be removed before the necessary polar alignment adjustment is calculated. I think this is a better approach, especially when you turn on protrack.
James

[frolinmod]

I absolutely believe in using Tpoint for polar alignment. It's quick, easy and quantitative. When you use Tpoint, it doesn't just tell you which direction you're off, it tells you 1) how many arc-seconds you're off in each direction and 2) which knobs to turn, in which directions to turn them and how much to turn them.

I just wish the adjustment knobs on the PME were larger and finer so that small differences could be more easily dialed in. Fractional knob "tics" are not easy to dial in. I do use Rob Miller's PME "wrench" set to make it a hair easier. In particular I find Rob's tool for turning the leveling knobs to be indispensable.

Did you know that you can put TWO bubble levels on the PME? I have two of them on mine, one on each side. They don't agree with each other. They don't wildly disagree, but they don't give identical readings either. I split the difference when I level the mount.

[strongmanmike]

I dunno...the PME just needs a good Polar Scope :shrug:...this took about 10min to align :D

http://www.pbase.com/strongmanmike2002/image/67531590/original

:lol:

The above was done after using the polar scope but I didn't use the scales in the scope but rather I had drift aligned in the past and memorised the field in the polar finder so just pointed the cross hairs at the known pole...I recon I now get it better than Taks guarantee of 2' just using the polar scope :P :thumbsup:..of course draw back is if you can't see the pole :doh:

Sorry Marcus, you know I love your PME (and you) and I would loooove a PME too but all this modelling required to get essentially what we have with our Tak mounts in minutes would be a pain if I bought a PME and remianed portable :eyepop:

Obviously in an observatory (and for many other reasons) the PME is king :thumbsup:

Mike

[gregbradley]

Pinpoint LE is not made by Software Bisque it is made by the Maxim DL company. So its not required in any Software Bisque application.

I think the free AAG automapper requires it.

Greg.

[gregbradley]

Hi Mike,

Did you find the FS2 controller improved the performance of your mount?

I don' think my NJP is capable of that image. But then maybe it is and all it needs is an expert with the polar alignment scope.

I don't know how you manage to use a Polar Alignment scope in the southern hemisphere - that is impressive. I even took a CCD image of the south celestial pole to see if I could find that trap of stars and still couldn't see it.

Greg.

[marc4darkskies]

Hehehe ... you've PA'ed so much you can probably do it WITHOUT a polar scope! :lol: ... just eyeballing it must get you close!

Personally I wouldn't dream of using (or recommending) a PME as a portable mount although I know it's done. I'll bet you though that the PMX will end up being the ultimate portable mount!

[strongmanmike]

Yeh I have polar aligned a few times :rolleyes: :scared: Does the PMX have a polar scope?



The FS2 is excellent, very simple and does the job, I didn't see any obvious improvement in teh tracking though - was still just as good with the previous Tak motors...and errr, you didn't read my post properly, I don't use the complex Tak scale visible in the polar finder, just the cross hairs. I did a very accurate drift align one night and then just memorised where the polar finder cross hairs were pointing, voila! now I just point and set. The particlular star field used to align off is pretty faint from a suburban location especially with the moon up, so that is one draw back of my method, from a dark sky it is very easy. I did the drift align back in 2005 so I adjusted for precession just last year :D

Mike

[marc4darkskies]

Polar scope is an optional extra.

By the way, speaking of polar aligning, I did it again last night. I twitched the altitude down and now it's perfect! As a friend of mine likes to say "... if it's worth doing, it's worth doing PERFECTLY! ...".

Model result (only 100 stars this time, 9.2 arcsec RMS pointing) is here: http://www.pbase.com/gailmarc/image/133024552/original

[gregbradley]

You da man!

Greg.

[gregbradley]

The FS2 is excellent, very simple and does the job, I didn't see any obvious improvement in teh tracking though - was still just as good with the previous Tak motors...and errr, you didn't read my post properly, I don't use the complex Tak scale visible in the polar finder, just the cross hairs. I did a very accurate drift align one night and then just memorised where the polar finder cross hairs were pointing, voila! now I just point and set. The particlular star field used to align off is pretty faint from a suburban location especially with the moon up, so that is one draw back of my method, from a dark sky it is very easy. I did the drift align back in 2005 so I adjusted for precession just last year :D

Mike[/QUOTE]


Oh I see, so you did.

How do you memorise a basically featureless field!! That's well done. I know there are some little asterisms like a J in the area.

I might try that approach with my NJP. I guess the problem I had was even at a dark site the polar scope doesn't have much brightness or resolution to show much. Perhaps I should give it another go.

I have the drift aligned position marked on my observatory ceiling at my dark site. I shove a torch in the back of the polar scope, it illuminates a little spot on the ceiling and I make a few minor adjustments (my house and my dark site observatory are not that different in lat/long) and its pretty close. So that's how I use my polar scope - its still handy hehehehe.

Greg.

Greg.

[Paul Haese]

I have my mount pretty close to the pole but I would like it better. Currently I am using Tpoint but doing the alignments with a reticle on the spare scope on the mount. This generally is ok but proves to be not consistent for PA purposes. I move the mount one way then the next Tpoint run it tells me to go the other. To be honest I would like to see a nice tutorial on how to setup Tpoint, automapper and pinpoint with sky6. I am sure that I am making a mess of this all the time and it would certainly help with my guiding.

Besides being able to do a 20 point run and then adjust after the equipment has done the work has got to be better. So who is up for a lengthy tut? BTW I have the catalogue too.

[marc4darkskies]

Are you using CCDSoft Paul? If so no lengthy tut is necessary and you don't need Pinpoint! AutomapperII is a breeze to use and their documentation got me going. http://www.newastro.com/downloads/automap2/automap2.pdf

It's worth spending an evening getting familiar with how it hangs together. Once it's set up doing another model requires no further setup.

Before adjusting polar alignment I now do a 50 point all sky model (30 to 85 degrees alt). It only takes 30 minutes! You might get away with 30 points but I wouldn't go less than that.

Before you adjust the alignment, you MUST (IMO) add additional terms to the resulting TPoint model to optimise its accuracy (and hence the PA recommendation). This isn't rocket science either. Go into the TPoint model you've created, open the fit data for the model and click the More Terms ... button. Then do Suggest Terms and Start. If the term at the top of the list improves your parameters (RMS and PSD) by 10% or more, click Add to Model. Repeat this procedure until your parameters stop improving. This is fairly quick & dirty (as opposed to analysing different combinations of model parameters) but it works.

The beauty of the PME is that TPoint tells you how much to twist the knobs. But I always prefer to confirm the alignment by doing another 50 point model.

Because of problems with my Laptop I only did a 100 star final model this time. Some argue that it's a case of diminishing returns to do more than that but I will when I get a new laptop and TheSkyX working.

[Paul Haese]

Marcus I am using MaximDL. I suppose I could use CCDsoft, perhaps I will take a look at it.

I am already using the extra terms and got the pointing down to 93 arc seconds at one point but now it is up near 125 after my last try at PA. I really need to sit down a bit more and read this stuff inside and out I suppose and then do it in the field.

[gregbradley]

I had the same problem Paul. Doing the t-point model manually isn't really feasible as it takes too long. And then as you say the recommendations can sometimes make the autoguiding errors worse.

I did a polar alignment using Pempros Polar Alignment wizard (the best software I have used so far for that). It got the PA very very close all by itself.

Then Precision PEC is possible (it requires a close PA to work).

Those 2 actions are getting me quite small guiding errors with 3 second guide exposures, callibrating the autoguider each time before I do an image run. But I do sometimes get slightly eggy stars so I am off a bit. it can vary by simply using a different guide star.
My typical guide errors are at the low end .05 and at the high end about 1.0, average is about .25. So pretty good really.

Automapper II does not come with a help file. It is on a separate link at the New Astro website. This tells you how to setup both the Sky6 server settings and same for CCDsoft. I am assuming that is why the plate solving failed when I used it last (wasn't setup properly).

I hope to use it next spare night (its hard to spend a clear night on fiddling with your gear when it is already working fairly well).

I am not sure if Automapper works with Maxim, probably not. Perhaps AAG Tpoint automapper works with Maxim as it requires Pinpoint which is a Maxim product.

Greg.

[marc4darkskies]

Beg to differ there Greg. Getting TPoint to recommend harmonic terms is perfectly feasible provided you have enough data points (50 is good). Took me a minute!!! No, I didn't spend ages optimising it, but that's not necessary. Just stop adding them when you don't get a 10% improvement. By the way, when I did this in TheSky6 I got almost identical accuracy to TheSkyX's Supermodel function with very similar polar alignment results. You need to optimise your model (by adding harmonic terms) to achieve a low sigma for your PA terms (a very low 1.5 in my case). If you have a high sigma for these terms the recommendation will not be reliable.

[Paul Haese]

Right then. I was trying to use Maxim, AAG and pinpoint (I made an error before when I said automapper II).

The pin point program has run out and the AAG was free and well maxim came to me from some other place (er I mean I ahh bought it).

So maybe I will go and get CCDsoft (must remember to load the drivers for the QSI if I do so it will work) and automapper II and see how this works. Do I still need to keep the GSC (star catalogue) or does automapper II use the sky6 catalogue?

[marc4darkskies]

Aaah, yes. You'll need to augment TheSky6's star database to improve plate solving. Check out which ones it supports yourself but I downloaded USNO-A2.0 which TheSky6 supports natively. It was free to download but I don't think it's available any more - it's been superceded. If you want it, PM me your address and I'll send you a DVD.

[Doomsayer]

If you are using the Sky6 you are limited to either using Pinpoint or CCDsoft for platesolving with either Automapper2 or AAG Tpoint Mapper as I understand. If you are using TheSky6 it really is worth purchasing the full pinpoint - DC3 can supply a disc with the GSC loaded - I find the GSC is sufficient for all plate solving with my 12"RC. Pinpoint or equivalent plate solving capacity also makes a lot of powerful automation possble with software such as CCDautopilot, such as precision slews (based on plate solves), dithering, acquiring stars for focusing or G2V calculations etc.

I don't have theSkyX, so I will not comment on Marcus's Tpoint mapping insights there as it seems to be far more self contained.

If you are not using Tpoint fully with the PME you are really under utilising capability and possibly being counter productive to its performance.

Before I moved to automated plate solving for mapping, I used to just map 25 or 30 points manually, by centering the star on a digital cross hair in CCDsoft using the main imaging camera bin2x2 and main OTA - it takes about half an hour or less to do this, using the n-s-w-e motion controls in TheSky. After 2-3 mapping runs I have the mount well aligned and then get typically 15arcsec pointing accuracy. The latest PME manual now covers all of this procedure well in my opinion. There are several Tpoint tutorials buried on the SoftwareBisque site, applicable to TheSky6 suite. It sounds like TheSkyX has made this stuff a bit easier.

[Paul Haese]

Thanks for the tips and help guys. I will go off and work this out. I am thinking that I will go with CCDsoft and automapper II. I will PM you Marcus for the catalogue.

[frolinmod]

You're making me laugh Mike. :rofl:

Honestly, the focal length you are working at with that gorgeous fast refractor is so low that polar alignment is probably good enough just by pointing the scope somewhere near North. Drool! I want one! Try working at FL=3911mm. Or better yet, don't. It requires very good polar alignment. In any case, Tpoint gets me there. :P

[rogerg]

For the sake of completeness and to help others who search for this in the future, I'd like to finish off my discussion earlier on my problems of night-to-night sync location/pointing.

I've found that my problem was my scripting. It turns out that during the night my scripts were causing the Paramount to flip sides of the meridian (unexpectedly) and when doing so perform a plate solve and synchronization (unexpectedly). Once this sync was done, the TPoint model was polluted and pointing off for consecutive nights (at best) or the plate solve was incorrect and pointing was off even more than just pollution of the model (at worst).

So, now that I have ensured there's no errant plate solves and synchronizing due to my scripst, I'm finding my pointing between nights is repeatedly within about 10 pixels (about 8 arc seconds) of the previous night. Very happy to finally sort this out so I can do more productive work with the mount.

My scripting is done using CCDCommander but it's not it's fault, it's simply my choice of settings in it, having come from a LX200 which didn't concern its self with meridian flips.

[gregbradley]

How do you program in meridian flips?

Greg.

[rogerg]

I'm not sure on all the details as I typically avoid going past the meridian, my eastern hemisphere is where I try to tay.

When taking images CCD Commander has an option to plate solve after meridian flip. During taking the image if meridian flip is occurs the plate solve will be done (if option enabled) and mount re-slewed to desired co-ordinates. I think.

Move-to commands will obviously flip the mount according to slew limits and setup options, so if object within x of meridian it will flip (and then optionally perform late solve and reslew also).

Roger.

[gregbradley]

Thanks Roger.

Greg.