LucMurphy

Sorry Robert I don't remember. And even it were yesterday, I probably coudn't tell what exactly did work. I uninstall/reinstall multiple the gps and virtural port drivers, i reverted back to an earlier version au autoslew, re-install it, try multiple usb port, tried another laptop that had the exact same system image, and other stuff i don't remember, it just started to work again... I hope you found it. Stay healthy Luc

DaveS, You mentionned that you don't have a motored focuser. If this is the case, you might have the same issue that i had while I was "in between" telescopes setup and waiting for the all the gear for a new focuser for the new telescope. By reviewing the sequence log, I figured out that Sequence was most likely expecting a focuser to be connected. After a few trials, I "installed" the ASCOM focuser simulator. ASCOM POTH has 2 focuser simulators, be sure to select the ASCOM one. In the "Current Location" setup tab, check "focuser installed", choose the ASCOM focuser simulator and verify that Sequence recognize the focuser when connecting (the focuser icon on the main page should become yellow-orange). In the "Focuser \ Autofocus during Sequence" tab, check Never and uncheck Begin Sequence with PreFocus Check. When setting your Target file, AutoSelect a focus star. The rest of the settings should be aligned for you telescope\camera. Hope this help. Luc You mentionned that you don't have a motored focuser. If this is the case, you might have the same issue that i had while I was "in between" telescopes setup and waiting for the all the gear for a new focuser. By reviewing the sequence log, I figured out that Sequence was most likely expecting a focuser to be connected. After a few trials, I "installed" the ASCOM focuser simulator. ASCOM POTH has 2 focuser simulators, be sure to select the ASCOM one. In the Current Location setup tab, check "focuser installed", choose the ASCOM focuser simulator and verify that Sequence recognize the focuser when connecting (the focuser icon on the main page should become yellow-orange). In the "Focuser \ Autofocus during Sequence" tab, check Never and uncheck Begin Sequence with PreFocus Check. When setting your Target file, AutoSelect a focus star. The rest of the settings should be the

Very nice!

Hi Mark, Not a trivial question at all actually but stranger than your answer suggests. The comport assigned to the virtual port device in Device Manager is not visible in Autoslew! (for completeness, the virtual port device is needed because the GPS can't talk directly program that communicate trhoug comport like Autoslew). Device manager also sees the GPS sensor (under the sensor grou). I had the same issue as you for connecting directly to the latop, but in my latest trails, both configurations (direct to laptop and usb connector) were tried. Although my usb cable was not heavily shielded. I will try that. Thanks Luc

Good evening fellow ASAer, I recently got a an issue with the GPS USB dongle. Autoslew is no longer "seeing" the GPS. The GPS sensor and Virtual Com port are both visible in Device Manager. To make sure it wasn't a driver issue, I downloaded the latest drivers from u-blox. I run Autoslew 5247 and Window 10. Anyone got a similar issue and have an idea? Luc

Got it! Believe it or not, it was a "cultural" issue. The Win 10 that was installed is the French version (even though I had the Win 7 English version) which handle the decimal point with a coma instead of a period. Visual Basic doesn't like. I change the language pack, and everything works perfectly now, including AS 5222. Thanks to this community for the support. Luc

Hi All, I got Win 10. Did not ask for it but got it anyway eventhough I always refused the autoupdate. In anycase, AS doesn't work. I tried the USB backward update as described in "how to recover the usb control". Nothing. Uninstalled AS 5222 to re-install 5219 and 5218 with going through the USB fix. Nothing. And i mean nothing. I am not even getting the error message "could not connect to controller". AS crashes after a fraction of second. I get the same thing if I connected to the mount or not. Any suggestion? Before reverting back to Win 7 I would like to give Win 10 a try because I read that PixInsight in no longer officially supporfting Win7. Thanks Luc

Yes it is possible. I had to replace the stock FLI Camera power cable because it is fairly rigid in warm temperature but it is getting solid in sub-zero temperature. Even with good cable management, it was dragging the mount. To make sure, you need to do a "time flex" measurement (in Sequence). The default parameter is measuring time flex when the tube points toward the zenith. To perform a better diagnosis, you may have to measure 2 or 3 more positions. The different positions will induce different tension in the cable (or should at least) and therefore should produce a different time flex measurement. Regards Luc

I concur with George. Even if you do not feel any wobble, the mechanical device that moves the mount up or down (being an electrical motor or hydro-mechanical piston) will take time to settle to a final resting position. Even worst, you could have minuscule slippage in the up position. I suggest that you do a flexure measurement with the mount in the most stable position (down) after several hours on being in that position and see what happens. Which brings me to a totally different subject. If I interpret the picture correctly, the imaging train is: Focal reducer OAG Focuser Filter wheel Shutter (the 65mm i believe) Camera Have you made sure that the back focus is 146 mm as per Celestron specs? Celestron has designed their focal reducer to have the same back focus with or without it: so it's 146 mm starting from the reducer flange.

I don't think you have a balancing issue, or at least not a big one. From my experience with a similar albeit scaled down setup (DDM60+C11), if you are getting the red lines reasonably close (let's say From what you wrote, I think the issue is flexure in the imaging train, not mount inbalance. You live in Utah which get freezing temperature at night. Is it possible that you went from 5" flexure to 30" from summer to winter? Don't laugh, that is what happen to me. I made several mod to improve the rigidity of my setup (documented in another email trail) but the biggest contributor was cable management that were getting hard in cold temperature and "pulling" on the tube therefore inducing flexure. In particular, the power cable of the FLI camera was getting rock solid in freezing temperature. I tried 2-3 setup but I ended up replacing the power cable (I know,I know, this invalidate the warranty) that went from the transformer box (which in sitting on the mount base) to the camera with a cold resistant cable that stays flexible down to -50 C. Problem solved. I am getting consistent 10 min unguided subs in any position. 15 min unguided is less successful but still in the 75% range. For my 20 min Ha, I have to guide though. The AP1200 mount will not remove the flexure issue. It will simply hide it by the off-axis-guiding. I hope this help a bit. Luc

I was just thinking about the same. How we going to have a Christmas gift under the tree next week? Luc

I kind of recollect that one DDM85 user had reported 45 min unguided subs with a C14 but i can't find the post in this forum. maybe it was in the old yahoo forum

I second Jay's recommendation to use Sequence hysteris and time flex measure tools. If you already are able to acheive subs of 400 sec undguide, it probably means that the hysteris is pretty much under control. To improve, first you need to measure timeflex before doing anything (that will be your baseline), try changes to your setup (hoping it will improve the ridigity) and measure timeflex again to see if the change had any effect or not. This is the only way because time flexure cannot be cancel with MLTP. In the world we are leaving, more expensive usually means better... but not always. In the old yahoo forum, there is an email exchange between P. Keller and a Tak FSQ-106 owner that couldn't get long un-guided subs (do not remember exactly how long, but it was much shorter than what you would expect for a short fl tube). In the end, they concluded that the Tak focuser was the issue.

Hi, To compare apple with apple, you should also add the length of the tube (moment of inertia) and the equipment weight ratio. OTA: C11 HD; fl = 1800 mm; 067"/pix; in my part of the world, the scope must have dew shield. It doesn't seems much but the shield those increase significantly the moment of inertia. Mount: DDM60 non-pro mounted on a "permanent" tripod (moving to a permanent pier soon) 80 points file Weight ratio = approx. 80% (equipment weight to DDM payload capacity) I get very consistent 10 min sub and about 75% success rate for 15 min sub. I did achieve 20 min, but the results are not consistent enough. I define "success" with a roundness of 0.1 or less as measure by Maxim. But what I found out that had the most influence on my setup was the rigidity of your whole setup. It is harder to compare apple with apple when talking about setup rigidity but here what I did to improve my setup that may help you with your C14. * Added a second dovetail on the top of the tube. Didn't use Celestron dovetail, they are crap. * Remove the ASA female dovetail and screwed scope bottom dovetail directly to the head of the DDM60. * Even though the EdgeHD has two mirror lock, they are not sufficient to prevent mirror sag over 10 min, Therefore, I added 3 "fingers" inside the tube to prevent mirror sag. * The secondary mirror alignment was done in such a way that it is no longer floating ( (always by tightening the screws). * Cable management: repalce the FLI power cable which was becoming rigid as a rock in sub-zero temp and inducing drift; i have one power cable bundle on one side of the tube and one data cable bundle on the other side of the tube. Regards Luc

Hi Jay, How to get MaxPilote to run Sequence and create a new MLPT (if you do)? Thanks Luc

hysterisis also affects MLPT but it is partially "removed" when the MLTP run starts. So, in my experience with my setup, time flex is sometime I needed to control more closely than hysterisis. Other may have other experiences. To make a long story short (remember, it took me 6 months of trials and errors to fix the problem), I made my setup more rigid by adding a second dovetail on top of the C11, made my rotable focuser non-rotable, added provisions to prevent main mirror flop and other minor stuff. All that allow the flex to go down to about 5-6 arc sec / 20 min. And then, it started to creep up again! I did noticed this time however that the power cable of my FLI camera was getting very stiff when temperature was sub-zero (I have the non-pro DDM60). I re-arrange the cables (for the 4th time), and I finally got a descent time flex 1.6 arc sec /19 min. I made a couple more flex measure and they all had similar results of less than 2 arc sec / 20 min. Regards Luc

The hysterisis will affect the pointing accuracy while the flex will affect your MLPT performance. Both error cannot be modeled. I saw hysterisis error from 30 arc sec to 60 arc sec (DDM60 + Celestron 11in.) depending on the season (I get from +20 degC to -20degC). Personnaly, i can live with a pointing error of a few minutes. Not great but it is workable. I was initially getting a time flex error of 10 arc sec / 20 min. that is definititely not good for long un-guided exposure. After a 6 months investigation, my time flex when down to less than 2 arc sec / 20 min! That's one of the beauty of this mount/sotfware: you have tools to do a diagnosis of the mount performance... Regards Luc

Correct, just an electronic finder. The SSAG is from a previous setup not involving the DDM60, so instead of living it sitting on the bench, I said why not make it useful.

Hi Gerald, Actually, the mini-dovetail is on the front end of the bottom rail, I am attaching the finderscope and some weight to the dovetail. you would think it is a cumbersome place to put the finderscope, but i never use it visually. A star shoot auto guider (SSAG) is always attached to it. Having the weight at the bottom of the tube has the advantage of lowering the center of gravity and hence the moment arm. Not by much but i saw a difference to when it was on the top rail. I estimate that this setup help me saved about 1 kg. My scope is all packed up for a local astrophoto workshop over the weekend but as soon as it is all up again, i will post a picture of the setup. Regards Luc

I had a similar problem. In the process of trying solving it, I went throught the same process as you on the software side with no real results. I then did several timeflex measurements with sequence to finally find out that the cables were introducing a drift that was orientation-dependant and that got worst in cold weather. The solution was to do a better cable management. I am not saying your problem is cable management (mainly because you have the pro version) but if you do a couple of timeflex, you could eliminate any mechanical/setup problem. Very important though, do a couple of timeflex in different orientations, not just pointing to the zenith, e.g. low north, intersection of celestial equator and meridian, etc. I hope this help Luc

I have the DDM60 and the Celestron 11. I may add some confusion to this topic but here is what I have done. I wanted to increase the telescope tube rigidity, so i bought the losmandy dovetail http://www.teleskop-express.de/shop/product_info.php/info/p1262_Losmandy-dovetail-plate-for-Celestron-C11.html as the main dovetail (connection between the scope and the mount) and I install the celestron dovetail on the top of the tube. I originally used the ASA dovetail clamp but i decided to be a little more creative. I removed the ASA dovetail clamp and drilled 4 holes in the losmandy dovetail (DO NOT, I REPEAT DO NOT DRILL ANY HOLE IN THE ASA MOUNT OR ANY ASA PROVIDED PARTS) matching the pattern of the ASA mount head (the losmany dovetail is aluminium, so pretty easy to drill). I then attached the losmandy dovetail directly to the mound head using the ASA provided screws. The dovetaill is now "permanently" attached to the mount. To easily instal and remove the scope, I opened the slots at the top of the dovetail with a drill so i can slide down the scope on the dovetail while I tighten the screws more firmly (the 2 screws are "loosely" installed on the radius block of the top side). This setup is somewhat similar to installing an ASA scope on the ASA plate. I no longer need the ASA dovetail clamp. This setup is cheaper than other solution and I achieve my goal of increasing the rigidity of the tube without increasing the overall weight. You need to be a little bit handy with power tools Regards Luc

Ian There are no stupid questions... I never noticed what you described because, like George, I sync with my planetarium software (Coelix) and never had any problem, so never had to investigate further. Not answering may also means that someone doesn't know the answer. Luc

Hi Christer, I had the same apprehension at first, but there is no difference for accuracy. I actually find the tilt adjustment easier to do than the conventional alt/az adjustment. Regards Luc

Thanks Philip, Yes, i have already notice that flex occurs mostly in the first few minutes, but not always, I've made 2-3 flex measurements with very steady drift (scope was point to the zenith). To be sure however, I have actually taken the habit of adding a 2 minutes delay after the end of the MLPT run before starting an exposure sequence. Not sure what you mean by: "Have you ever measured the real trailing by making short 5s exposures every minute and then determine the pixel localtion of a certain star ?" I have bieng using the time flex measurement in Sequence. Or are you talking about something else? I know SC are inherently more difficult to make more rigid but i still hopeful. I will start making measurement with my Canon to see if the weight of FLI MicroLine+CFW could be the source of the flexure. Thanks again Luc

As anyone had experience making a diagnosis of flexure with the Sequence time flex tool? I am trying to do so by making time flex measurements in different part of the sky (incuding pointing to the zenith) hoping it would give me a clue what needs to improve in my imaging train. The first thing i noticed however is that sequence gives me a much shorter unguided time than what i can actually acheive. Sequence gives me a fairly consistent 8-10 arcsec over 20 min time flex (for sequence that's an equivalent of 1-2 min unguided with 1" error) while i can achieve consistent 5 min unguided subs (10 min unguided however is a challenge) Before anyone ask, my setup is: DDM60 Celestron edgdhd 11" (with miror locks) Moonlite focuser (I have order from Moonlite a special drawtube, so i am confident that the filter wheel to focuser connection is rigid and i have not notice any slip) FLI filter wheel FLI MicroLine Total payload 21-22kg The pointing file is excellent and Autoslew says I'm .5'/1.5' from the pole. I have a permanent setup. Any ideas? Thanks Luc