GeorgeCarey
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Posts posted by GeorgeCarey
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I have not been in the forum for years. My DDM60 is still working well, but I am getting older. I can see the time when I will have to pass it on to someone else.
With this in mind, where can I download the instructions for Autoslew and Sequence?
My copies are on paper and getting very grubby. I have had a look at the Astrosysteme website but can not find downloads.
George
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Waldemar - I would not hold your breath....
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Which version of Maxim do you use?
Mine is an old one, 5.2 I think, and works very well.
The only annoying thing is that when focussing, it draws the V curve and then plonks the focus miles away from the lowest point.
I nearly always have to look at the numbers and adjust.
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I think 'Waiting for telescope' is an Autoslew generated error - but it is so long ago that I had such problems I have forgotten.
My problem last night was, I think, a USB lead error. The dome stopped rotating with the scope which I spotted when the stars started to distort as the dome slit obscured the telescope.
I disconnected and reconnected the dome and all was well.
I am using everything now and so far no problems.
I was unaware of Diffraction Ltd stopping Maxim development - bad news!
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Tonight I am getting an error that I have never had before. I tried to centre a star in Maxim with 'Move telescope here' and I get 'Telescope busy'.
Disconnect scope and reconnect and then I can centre a star. But there is no after slew image.
I tried to start guiding and the guide commands were not getting to the scope. Disconnect/connect and now guiding works.
I am expecting to get another error after the image is taken because I am dithering between images.
Any ideas?
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Thanks Nigel. I will have to bite the bullet and learn some Python. I have ordered a teach yourself book. Thanks for the tips.
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Thanks. I posed a question on Astronomy StackExchange and everyone says 'Python'! It looks like I will have to learn some Python programming.
There is a Python interface to the Nasa CFITSIO lib so I will have a rummage through that.
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Thanks, I have seen most of those links. We can read the files fine now and convert to bmp.
I have been looking at astrometry. From the FITS header we have the image centre coordinates and plate scale plus rotation.
I have got a spreadsheet working to find the coordinates of an object so that the relevant area can be downloaded from PanSTARRS or Simbad.
Far from the centre of the image errors creep in. The process of converting pixel coordinates to real world is horrendously complicated.
My system uses TAN - gnomonic projection (there are about 20 different projections!)
I am not sure I am up to sorting that out.
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Screen grab Win10. Little known trick.... Hold down Windows key and shift key and hit 'S'. Drag area. You will get the opportunity to do some editing like highlighting and then save your image.
Your welcome!
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And the spreadsheet - dealing with the peculiar values of BZERO and BSCALE:
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Good progress made. I decided to hack into the FITS files myself - the hard way!
I have no way of reading Hex values from a file so found a hex reader on the web, and a hex to decimal converter.
I can now read the 16 bit FITS files and get exactly the same adu values out as Maxim does.
I then wrote a spreadsheet that would do the task - success.
Lutgen found a bug in his code late last night - an overflow was occurring, so I think we are back on track.
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LaCebra - that looks very interesting! I will pass that along to Lutgen. (the programmer).
We have a small problem reading FITS from another friend of mine.
In his header there is a keyword 'BIAS' which does not seem normal. It is not to do with bias calibration frames.
It does not seem to be a standard keyword?
In his reference image he has BZERO=33753.0 and in other images it is the usual 32768.0 (2^15)
Also his reference image has BSCALE=0.9699392681661427 and in others it is the usual 1.0000
Very odd.
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Thanks La Cebra,
My friend programs in Delphi and it looks like there are no FITS libraries available.
He is having fun working it all out from scratch!
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Great progress. We are now able to extract adu values from the fits file that agree with Maxim.
The hardest part is done!
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Are there any experts on FITS images out there?
I have a friend who is a whizz at programming and have coaxed him into developing software that can take a few FITS images and search for new objects.
In other words, automated nova/supernova detection.
He has had some success in reading a FITS image, despite the incomprehensible information about the data structure.
For some strange reason, we are getting the right hand 280 columns appearing at the left - despite reading the data sequentially from the start.
The image is 3326 x 2504 pixels.
Very stretched image below:
Any help would be much appreciated!
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My W10 seems ok. When it says updates are there I ignore them but eventually it will take over and do the update.
I believe it is impossible to turn off updates.
A friend with W10 has huge problems. Nearly every update makes some software crash - often his internet browsers.
He has had professional IT people try to help but problems persist.
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It would be interesting to know who made the mirrors. I don't think ASA make their own mirrors.
Clearly the coatings are very poor quality.
I made a 6" mirror in 1985 and the coating still looks excellent. The coating was done by David Hinds in the UK.
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Very interesting! It looks like the 100 will go on an ordinary pier or tripod.
Pity not many details are available.
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This is the spreadsheet.
http://geoastro.co.uk/asa/Motor_current_analysis_V20.xls
All you need do is:
Get the logfile
Select everything (CTRL-A)
Copy (CTRL-C)
Click on the button 'Process'.
A graph should be displayed.
I haven't used the spreadsheet for years so there may be bugs. It was written with Excel 2003.
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I had huge problems with this sort of error and my mount went back to Austria several times. In 2015 it was finally sorted out. Nobody ever found a definitive reason for the problem, but it was most likely the bearings.
I monitored the motor currents and wrote a spreadsheet that displayed the currents on a graph. It could clearly be seen that the mount would track ok but the current in the
RA axis would slowly rise. When it hit 5A the mount would throw an error message and then do a slew to try and fix the error.
I will find the spreadsheet and send a copy.
When the mount last went back to ASA I asked them to run it for at least 8 hours and send me the log file.
The currents stayed steady well below 1 Amp so I was happy to ask for the mount to be sent back.
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Hi Adamo,
I also have a Ddm60. Once you have done the homefind then the mount does know where it is. But if you don't do a homefind the mount is unaware of direction. The homefind looks for the zero position on the encoders.
The bigger mounts don't need to do a homefind.
George
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Sounds perfect. 300 clear nights a year - I get about 50.
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Thanks Lukas. Great set up. It looks like there are other flat roof buildings there. Are other telescopes hosted?
User manual downloads
in Software
Posted · Edited by GeorgeCarey
Thanks. I have registered my DDM60. A bit odd - I was one of the first to buy an ASA mount. They should have my details.