MartinN

Hi Aaron, hi George, I encountered the very same situation last night, and a few nights before, and some weeks ago, too. Balance was good, but with 1,5A values, supposedly due to the weight of ASA12N+CCD-Camera+Filterwheel and balancing counterweights. Last night I noticed, that the red led of the laser switch at the RA mount baseplate blinked, when the problem occured. Though I stopped Autoslew, disconnected and unpowered the mount, the blinking red led showed up again after powering the mount. When connecting USB, the blinking change to usual contant light, but the tracking problem occured again after a few minutes. When the problem started, the mount began to make some strange noise like jarring, buzzing, rattling. When tracking stops eventually, it seems like the motors are not powered any longer, and the button in Autoslew, for turning motors on an off, has no effect at all. Maybe I have to inrease the "Measure Time", and decrease "Step Size" and "Test Current" to get a more sinus like pattern (which is not so up to now) when setting motors on in Autoslew after powering the mount ? Which values do you have with a rather heavy tube (and thus counterweights, or counterweights near shafts end) ? Kind regards Martin

Hi Ron, processing these data was really worth it: the core of M56 is well resolved, with stars of different colours, and the number of stars in the whole field is not too high, so M56 itself clearly stands out. The only little obstacle for comparison with star charts was the orientation of the image, with north at bottom... I like your detailed description of processing steps in PixInsight, even with parameter values, very much. They give a good hint, how to achieve these imaging results you present here regularly. Furthermore, I have a good starting point for processing LRGB and narrow band exposures from these descriptions now, as I start using a monochrome CCD with filters (in addition to the OSC CCD used for the last years). Thank you, and kind regards Martin

No problems with DDM60 (version of Oct. 2010) and Windows7 (Starter (32bit), on a EEE-PC R052C running Intel N2800).

Pavel, what a great result ! Some noise in these 100% crops makes the appearance more naturally... at least for me ! Kind regards Martin

Hm... so I will await the new version of Autoslew and/or Sequence. Btw, I found the code of the Module1, which has functions save() and savemanual(): the last line of the function is Application.Quit That seems to be the reason for exiting when saving the object list. Clears skies Martin

Hi Thomas, this is a wonderful imaging result, all time for processing was woth it ! It looks, like the "Hidden Galaxy" was eventually uncovered from foreground stars, milkyway nebulosities and dust in this "historically" zone of avoidance. Kind regards Martin

Hi George, excellent; thank you for all this detailed information, and the spreadsheet with hints. Maybe I can find out, why the spreadsheet closes, after saving the Object List ;-) I am still thinking about, how to synch the MaximDL exposure start and these slews from the Object List. Perhaps the next version of sequence supports such synchronization. Up to now, I use comet tracking of Autoslew regularly, and it works very well. The only obstacle for perfect pictures is, that when using the dither function in Autosave Setup of MaximDL, the target coordinates for every dither step are transmitted from MaximDL to Autoslew in absolut values, all dithered around the starting RA and DE values. This drives the mount back to the "dithered" coordinates of the first exposure every time. Though comet tracking still starts at this position then, the comet itself moves out of the image area, if it is to fast relative to the stars. If the MaximDL dithering would send e.g. relative differences to the actual target position of the mount (not sure, if ASCOM allows this) or determine the actual position and apply the "dithering deviation" for calculating the new target position, it would thus lead to dithering for the photographed comet, which would remain in the same imaging area. Do we know, if an Autoslew Object list supports comet tracking speed values beside RA and DE values for every object in the list ? This would be an ideal solution for long time comet or ISS tracking, due to accepting changing speeds, at least from step to step. Kind regards Martin

Hi George, you wrote "The spreadsheet produces an object list that Autoslew can use to point to the object." That sounds if it might be a solution for tracking a really fast comet, or a even faster NearEarthObject passing by (maybe, the ISS ). For comets I just used the comet tracking provided by Autoslew. But this is insufficient for a NEO or the ISS, due to its changing arc speed during the passage. So, it would be great, if you could make the spreadsheet available ! Together with some hints, how to feed the spreadsheet data into Autoslew... Kind regards Martin P.S. Fine, at least Denis is lucky due to clear skies... we are suffering from cloudy nights here in central europe but not worrying to much, due to the nearly full moon these nights.

Hi Thomas, a very nice image, with We 1-10 clearly visible ! Since you have imaged this field @ vdB 134 with Hα as well, just a question: can you see this planetary nebula, when the Hα subimage is NOT added to the LRBG composition ? No need to publish such version, and maybe you even have the resulting image already at hand... and can perceive more than a trace of We 1-10 therein ? Kind regards Martin

Hi Kruno, like you and some others, I use my DDM60 in the field every time. Up to now, there have been no problems at all due to any condensation, or moisture... or even these transformed to frost during the night. Some times, the most critical moments are when carrying the mount back from the tripod to the car in the dawn: I had to wipe dry the mount to reduce the risk that it would slip out of my hands then. Kind regards Martin

Lukas, Daniel, I can confirm to statements given by Robert and Mark, I often use only the 3 star PA routine, too. Out in the fields, a big pointing file delays the start of intended imaging, and MLPT works precise, even when comet tracking is activated in addition. Flexure changes, due to temperatures falling, might be the cause of tracking problems during long exposures, when MLPT is setup for more than 60 minutes. Daniel, did you ever check for changed flexure after 10 degrees lower environmental temperature ? Regards Martin

Hi George, can you please indicate the field of view shown in the images above ? This makes it easier to compare pointing results. Up to now, I never tested pointing accuracy of my (totally mobile) setup. On the other hand, its really time to do this just to know about the results, and even to do a hysteresis measurement (which helps to determine effectiveness of a 10-40 star pointing model). I will perform these tests, and report results. Might take some time due to weather conditions here... Regards Martin

Hello Friends, since a few weeks, I own an ASA astrograph, with a 3" Wynne corrector. This 3" Wynne corrector has a serial number graved on the body. Until then, I used a 200m 1:4 Newton, which is equipped with a 2" Reducer-Corrector, having the very same dimensions as the "ASA 2" Reducer Corrector 0.73x". I am not sure, if this corrector was made by ASA, because there is no serial number engraved on the body of this 2" corrector. Can those of you, using an ASA delivered "2" Reducer Corrector 0.73x", confirm if there an engraved serial number on the body of the 2" Reducer Corrector ? At least, this would give a hint of the origin of my 2" Reducer Corrector... Thank you very much ! Kind regards Martin

Dave, for me, the "destination iPad" must be an option only. The touch screen solution might appear very simple for the user, but I suppose even you would always like to know what's inside, what happens in the background. For a fair amount, I'd like to know exactly, what goes on behind the scenes. You are right: Astro-imaging is challenging enough without having to worry about platform issues. However, the integration of all components of a complete and perfect astro-imaging platform might restrict users to components they do not consider optimal, or too much expensive for their budget. To handle Autoslew, MaximDL, Sequence and even more programs in parallel is hard, but integration of Autoslew together with Sequence has been anounced and will be another good point against competitors. Even they are climbing the bandwagon with wireless services... but fail to avoid mechanical limitations and continue to sell ancient drive technology, mixed now with high resolution encoders (thus documenting unavoidable periodic errors). Kind regards Martin

Wojtek, thank you for these hints, they enabled me to setup very quickly Focuser operation from the joystick. Especially, the COM-Number-Axis-association (Axis setting below OK3-SM2A) did the trick ! In addition, I set in MaximDL at Observatory Control - Setup - Focuser 1 - Options - Chose... the "AstroOptik Server Focuser", and MaximDL can control the focuser in parallel, for e.g. autofocus. Kind regards Martin

Thomas, these FWHMs of 4.6 to 6.8 px are not that bad, in my opinion. Considering the px size of 4,7µm, FWHMs equal to (linear) 21.6 to 32 µm, which are below 2.8" to 4.1" at 1620mm focal length after a single 15 min exposure. Furthermore, the good value is well below the specification in matrix spot diagrams of the 2" Barlow Corrector at the 250mm f3.8, available at ASAs website. The smallest FWHMs I got with 5min exposures were 2.8" with 5,12µm px size (at 1860mm focal length), when seeing was among the best low values of the year (I will post the image here after processing). Still an argument FOR this long focal length instrument. But the easier focal length selection anytime by using the appropriate corrector at an f3.8 or f4 mirror telescope is a clear advantage, balancing out the comparable resolution of an extra instrument (requiring a complete exchange of the telescope, maybe even at night). Kind regards Martin

Hello Thomas, it is amazing, how much fine details are visible within Stepahn's Quintet. The resolution of the whole image field seems very good. This is astonishing, considering the subexposure lengths of 15min. Can you give statement, which FWHM in pixels the nonsaturated stars (such with maybe 2000 or 1500 counts of pixel value) have in these subframes ? What is the FWHM shown in Fitswork, for example ? I am thinking about moving to a single telescope solution for both astrograph use (F/3) and long focal length photography (F/6.8). That's why I ask such questions... Kind regards, Martin