steppenwolf

I hate to say this but you know what? I had more fun and got more imaging done with my old blue tube ED80, EQ6 (EQMod) and SX M25C than I currently get with my 'inheritance' outfit! Sadly, my experience has been that spending more money does not necessarily, a better image make - I even sent my own FSQ 85 back for a refund because I wasn't happy with the results! The problem with better gear is that one's expectations climb unrealistically which is why my current project (automation) is aimed purely at increasing my time on the sky with the gear that I already have. What better gear should do is put the onus on the operator to get the best out of it and not blame the equipment if the results aren't great but the risk is pixel peeping - something I have done too much of in the past - now I just want to capture some photons during the gaps in the clouds ........... I went through this with Hi Fi at one time and realised that I was listening for the 'pops' and 'flutter' and missing the music!

Indeed, this will confirm whether or not there is sensor tilt - be aware though that there are other potential causes for the sensor to be tilted to the light cone including focuser slop, that awful adjustable connector that you get with the FSQ 85. I would agree that the diffraction spikes on the bright stars are indeed the micro-lenses on the KAF 8300 sensor as this is a well known issue with this chip (note that the spikes are exactly N/S and E/W in the field of view). Ollie makes a very valid point about the 'pixel peeping' though (and many of us including me are guilty of doing it) - your image is far removed from a disaster and with our limited imaging opportunities, you could just get on and enjoy yourself!

That's good news, Martin, an excellent achievement. I am sure you are right about it being something simple hence me 'simplifying' the command chain by the removal of POTH. I thought I had approached this issue in a logical and structured way but the next set of tests will be even better documented - I am going to run logs for the guiding and as well as noting the various settings and rather than just noting 'failed', I'll make a specific note of the error magnitudes of both RA and DEC !! This should help to pin down which permutation of the various settings heads me in the right direction. Please, weather, cheer up an' gimme a break ......... Good job, I'm enjoying myself even without the imaging!

Sensor tilt can be a bit of a nightmare to resolve but it really boils down to tightening everything up within an inch of its life at the point that you are as positive as you can be that all the component matings surfaces are flush with one another. Polar alignment? Could be but I suspect that you have that nailed?

To my eye (but please bear in mind that I wear vari-focals), the bottom left and bottom right look pretty good to me - this could be a case of sensor tilt rather than tracking?

The Mesu mount may well do so but the big wide filter carousel on the camera won't as at one altitude and one camera orientation (that I have to allow for), the camera and mount will meet up for a close and personal tête-à-tête!! ACP does seem to be the system of choice but as we've discussed, at such a high price - Janie would just say 'go for it' but that is hardly the point ..... How difficult can it be for the current system to just reverse the commands? :grin: What is particularly frustrating is that the 'difficult' part of re-aligning the field of view to match the pre-flip images through automatic plate solving and re-acquiring the guide star works seamlessly If I have to go the ACP route, I guess I will but I am so nearly there at a much lower cost ..... SG Pro will work with the Mesu in this regard but, I'd have to stop using MaxIm DL and replace my observatory PC as it runs Windows XP and I am very reluctant to do so.

Thanks, Sara, we do put ourselves through the mill don't we? :grin:

It's horrendous how the costs mount up isn't it? :grin: I have to say though that despite the problems that I have slowly knocked off one by one, I have had a blast with this project. The thrill of resolving seemingly insurmountable problems is immense although I am rather losing the will over this current autoguiding issue!

Additional Note 13 - Unfortunately the Project is currently stalled as I battle with restarting autoguiding after a meridian flip! I've spent far too many hours trying to resolve this issue and have tired numerous permutations of the settings, asked on all the relevant forums and Yahoo groups all to no avail! Last night's clear sky (rather squandered on testing!) gave me a further opportunity to carry out more testing and trying to reduce the time for each test led to a strange issue - if the meridian overlap was too small, the mount would just stop, not flip!! So, I am back to a 03:45:00 overlap. I currently control both the mount and the dome via POTH but today, I have decided to try and take POTH out of the equation thus putting control more directly in the hands of MaxIm DL so I guess it *might* mean that some of the guiding permutations in MaxIm DL may have some more relevance.This seems to work very well during daytime meridian flip tests but only time will tell if it makes any difference under night skies. Sadly, if I don't find answers to this issue shortly, I will have to start looking into using a different orchestration program or just accept that after a meridian flip, manual intervention will be required!

I'm delighted that the thread has been of some use, Andrew and I wish you luck with your own project - mine has been done on a much smaller budget than yours but it can be done I feel sure, despite the set-backs and problems that I have 'enjoyed' and detailed on the way! I've had some really helpful assistance from the knowledgeable people on SGL and you are right - this is a great community .......

Additional Note 12 - Unfortunately the autoguiding after a meridian flip failed to work correctly! As a test, I arranged to capture some OIII data of the Eastern Veil to add to the previous Ha image, about half an hour before a meridian flip was required. The capture of the first three frames went without incident and the mount flipped right on cue having plate-solved to determine its last position. Having flipped, a second plate-solve was carried out followed by a tiny pointing adjustment, the camera was re-focused and the guide star re-acquired. So far so good! Sadly, as guiding re-started, the guide star moved steadily out of the field of view until it was lost! The system had failed to reverse the control movements following the meridian flip....... There are so many ways of initialising and controlling a meridian flip and its aftermath and what I believe is happening here is that there are too many systems vying for control:- 1. The Mount Controller 2. MaxIm DL 3. CCD Commander The key is to ensure that I pass all the control on to CCD Commander but I await a clear sky to determine if the changes I have made will resolve the issue. Meanwhile, although 3 subframes of OIII is far too little, I couldn't resist adding them to my earlier Ha data so here is the rather noisy result!

ADDITIONAL NOTE 11 - My first Semi-Fully Automated imaging session completed successfully - nearly there! Why only 'Semi'? The imaging session started after the object had passed the meridian so I didn't have to complete a meridian flip and guide star re-acquire! Now, I know that the mount will successfully complete a meridian flip and during the most recent session, the system successfully re-acquired its guide star every 30 minutes following a re-focus/plate-solve but so far I haven't carried out a meridian flip and guide star re-acquire at the same time ...... So where are we with the project? 1. The system checks that it is dark and dry and if so, 2. The Dome aperture opens, the CCD camera is cooled in three stages to -20° C 3. The Mesu 200 mount un-parks automatically, slews to the object chosen for the session 4. At the end of the slew, the dome is 'coupled' to the mount and rotates to align with the telescope 5. A plate solve image is captured, the mount is synchronised with Cartes du Ciel and a fine adjustment (if required) is made to acquire the correct framing of the object 6. A suitable mag. 6 star is chosen by PinPoint Astrometry and the telescope slews to the test star 7. The camera selects the Luminance filter and carries out an auto-focus 8. The mount slews back to the chosen object, plate-solves and fine-tunes the pointing if required 9. The L filter is swapped for the Ha filter and the previously computed offset applied 10. A suitable guide star is chosen, autoguiding starts and the first of three 600 second exposures is captured 11. After the third image has been captured, the telescope slews to the focus test star, selects the L filter and carries out an auto-focus 12. The mount slews back to the chosen object, plate-solves and fine-tunes the pointing if required 13. The L filter is swapped for the Ha filter and the previously computed offset applied 14. The guide star is re-acquired and autoguiding restarts 15. The first of the next set of three 600 second exposures is captured 16. This is continued until all the images have been captured (in my case 10 sets of 3 images - 30 in total but see later for the failures) 17. After all the images have been captured, the dome aperture is closed and the dome is 'de-coupled' from the mount to stop it following the mount 18. The mount is parked and then the dome is parked as well 19. The camera is warmed up to ambient temperature in 3 stages The following image, although not a prize-winner, was captured while I slept comfortably in bed but in truth, it was with some relief that I looked outside in the wee small hours to see the dome was indeed parked and closed! So what's next? Well, the last 6 exposures were rejected because of cloud/mist cover as I have yet to calibrate and enable the cloud sensor part of the weather system so this final weather calibration must be carried out soon. Next, I must test the meridian flip/guide star re-acquire system. After that, I will have achieved my original goals bar the final test of a close-down through bad weather followed by an automatic re-start but, you know what?, although a nice feature to have, I'll be happy with what I have already achieved!

ADDITIONAL NOTE 10 - Plate Solve/Focus Hiccup but now sorted! Plate Solve A couple of weeks away and poor weather have put automation implementation on hold but I've now got back into it. However, at the same time as implementing PinPoint (full version) I also upgraded to MaxIm DL V6 as this has a couple of potentially desirable features added since V5. Unfortunately though, this exposed a strange bug where the image capture feature hung when changing filter and starting a plate solve 'action' - CCD Commander would issue an error message that just stuck in a loop. The 'action' starts but when it gets to 'Setting Filter to Ha', it just sits there and then I get the following error message:- 'An action cannot be completed because a component (MaxIm DL Pro 6 - CCD image 4) is not responding. Choose "Switch To" to activate the component and correct the problem. Switch To Retry (Cancel greyed out) CCD Commander has a 'feature' that by default forces a dummy image to be captured prior to changing the filter as this apparently adds some stability in certain installations but in my case this caused a problem Disabling this option improved reliability for not 100% so I reverted back to my trusty MaxIm DL V5 and the problem went away! Focus Next up was focus after a plate solve using FocusMax and this worked most of the time but sometimes failed with narrowband filters - this is just a bit of fine tuning for exposure values and flux densities but a chance discussion with Sara Wager revealed that she only focuses using her Luminance filter and uses offsets for the other filters (this allows for filters not being truly parfocal within a particular optical system and in my case, I have different makes for wideband and narrowband). Now, I had considered using this method but was concerned about backlash in the focuser drive gearbox but as Sara uses it very successfully, it was worth a try. Last night was fairly clear so I had an opportunity to determine the required offsets and build them in to the system. I used the following work-flow that compensates for changes in temperature during the calibration process:- 1. Autofocus using L filter to check that all is working well and check focus on a bright star with a Bahtinov mask noting focus position 2. Use CCD Commander (CCD C) to change filter to Ha and take an image with Bahtinov mask in place 3. Use ‘Jog’ in FocusMax to adjust focus until perfect and then issue 200 steps out followed by 200 steps in and check focus with mask noting focus position – still perfect in my case 4. Enter offset in CCD C 5. Select 'L' filter using MaxIm DL, use Jog to return to original ‘L’ position, then issue 200 steps out followed by 200 steps in and check focus with mask, adjust if necessary noting new focus position if required 6. Repeat from 2. for each filter entering each offset with reference to the current ‘L’ position. After a short while, the L position remained constant so the temperature had stabilised 7. Use CCD C to take an image of a bright star using each filter in turn using the Bahtinov mask returning to the 'L' position first to simulate an ‘L’ autofocus and make sure each image is correctly focused – which they were As a real bonus, I discovered that plate solves have now become completely reliable using the 'L' channel only. I have one last, possible task to consider with regard to focus and that is to calibrate automatic compensation for temperature shift but as I will be re-focusing automatically every 20 minutes, I may just miss this one out! Auto Acquire Guide Star I rarely have an issue with auto-guiding using MaxIm DL but last night I did under CCD Commander control. It turned out to be a trivial fault caused by the first guide star capture reverting to requiring a 'Simple Dark Frame' by default but I have now switched this default off and re-saved my configuration file - hopefully this will ensure that the default is disabled in the future using the current configuration. So, the fun (and a certain amount of frustration!) continues but the end is now in sight ........ maybe .......perhaps ........possibly .........hopefully ......... :grin:

I am really pleased that my experiences of dome automation have been of help - I too have had some great help from others along the way. Full automation is absolutely not required to achieve a decent boost in your imaging opportunities and your requirements outlined here will allow such a boost. Here is a screen dump of the POTH settings (The Lat. and Long. are fictitious) but if I can assist any further, just let me know what you need. I am using a Mesu 200 mount with a pier slightly offset from centre. How I arrived at those figures is shown on page 3 post #51, you will have to use your own measurements, of course and getting these right is crucial to ensure accurate positioning of the dome slit.

Thanks for your input, Trevor, I can do hardware and electronics (see my aperture controller post) but my software production days ended with writing my own order processing system in FoxPro and Windows 98!! I'd like to get to grips with VBScript but truth is, what I really, REALLY want to do is just get out there and start imaging again!!

As usual, Martin, there is no 'one size solution fits all', but I really want my solution to be CCD C ! The trouble is, there are so many variables in this game!

Thanks Martin - I am hoping that long-term I haven't jumped in the wrong boat with CCD Commander rather than SGPro but, time will tell! I would really like that feature but it's not enough to pull me from the CCD Commander/MaxIm DL combination. Maybe I can write a VBScript to do it if CCD Commander can't ........

Hi Martin, Not completely sure of what you are saying here, just to clarify:- 1. are you saying that both CCD Commander/MaxIm DL and Sequence Generator Pro will automatically carry out a blind solve if the PP6 solve fails? 2. if the answer to 1. above is yes, do you happen to know if, following a blind solve, the system will then carry out a PP6 solve using the updated coordinates?

ADDITIONAL NOTE 9 - PinPoint Version 6 I have taken the plunge and bought the full version of PinPoint instead of relying on the LE version that ships free with MaxIm DL. This full version of the software will work with FocusMax's 'AcquireStar' feature that will automatically choose a suitable focus star of the correct magnitude near to the current pointing of the telescope. This will save the pairing exercise that I was contemplating earlier but I have also discovered an additional 'bonus'. Accompanying the full version is a built in feature that will do a 'blind solve' - a blind solve is a plate solve for which the current RA/Dec is unknown so it could be anywhere in the sky. This feature is slower than using the PinPoint astrometry engine and relies on an Internet connection to astrometry.net but I have been a beta tester for this Internet engine for some years and it works very well indeed. This plate solve is pretty accurate but not perhaps as accurate as PinPoint itself BUT if the mount happens to have a pointing error outside PinPoint's search parameters (perhaps after a meridian flip, for example) the blind solve will furnish PinPoint with an accurate enough pointing location to allow a full accurate solve in a single pass - magic! Unfortunately, as far as I can see, CCD Commander will not action this feature automatically but I have been in touch with the developer to see if this can be added to the feature 'wish-list'. As a minimum, it will be useful for the single star alignment that I carry out at the beginning of each session - ESPECIALLY when my beautiful grand daughter Lexi has head butted the counterbalance bar when playing 'hide and seek' and upset my carefully prepared park position........

There's a lot to get right, Martin and using a wide range of disparate software only adds to the integration issues! In isolation, each function is working very well indeed although the focusing will require some planning - I'm thinking of making up some 'pairs' comprising a deep sky object and a local suitable mag star. Plate solving works well but as PinPoint LE is not a blind solver, the mount does need to be pointing and synced in the right area and within the solver's pre-set parameters. The sky model should have resolved that. Meridian flips work smack on - I have mine set to go 15 minutes after culmination and the dome waits for the mount to finish before it slaves. The dome itself is working perfectly and I am always amused by how accurately the AZ moves and positions itself so that the telescope points right through the very centre of the aperture. Weather monitoring is 2/3 there with light intensity and rain detection working predictably and cloud detection getting there. Camera cool down and warm up and, of course, filter changes have always been issue-free although I haven't yet decided whether to use focus offsets for the filters. A change to the flats parameters to allow slower exposure times with the automatic flat-flap seems to have worked so that box can also be ticked. I've yet to re-try the auto acquisition of a guide star but I have learnt my lesson over that one. All in all, I have made some good progress but you can see why I chose the Summer months to set this all up can't you! Ironically, even if I don't capture a single image this season, I'll still have had a lot of fun!! Sent from my iPhone from somewhere dark .....

ADDITIONAL NOTE 8 - Dome operating perfectly - rest of software challenging :- With the Pulsar Observatory itself working absolutely perfectly - I highly recommend this manufacturer if you are in the market for a manual or motorised observatory - I have turned my attention to the rest of the installation and this is proving challenging. I am learning pretty quickly that FocusMax is very choosy about the magnitude of stars that it will focus on although when I choose the right star, it works flawlessly - some careful pre-planning will be required here. I have finally produced a new sky model for the new installation so am hopeful that my failed first star alignment plate solves will be a thing of the past as the mount is now slewing incredibly accurately all over the sky so that the plate solve will be working on a portion of sky within its search parameters!

Thanks for the link, Martin, part of the circuit is the same as mine but the arrangement of the current direction relays in my circuit is very different as in mine I use two DPDT types but don't use D4 and D5.

That's interesting, Martin - I am using a one-way RF link from the main controller (the one that houses the Velleman board) to the aperture controller so there is no physical feedback from the aperture controller, just the time-out which is generated by the software. Do you use a two-way RF link or a set of contact plates?

ADDITIONAL NOTE 7 - Nearly ready - DOH! :- The replacement shutter controller was recently installed by Dave and Trevor from Pulsar and since then, I haven't had a single failure of the limit switch system which is very good news. The operation of the shutter is now very much more reliable although I have still had the occasional instance of the system failing to close under software command during extensive testing. A full automation run proved interesting and disappointing at the same time but nothing to do with the Pulsar dome automation itself and everything to do with me not having everything set up correctly. The camera was automatically connected and started its controlled temperature reduction in 5 degree segments down to -20 degrees C, the aperture opened, the mount slewed and the dome synced correctly with the mount but PinPoint failed to carry out a successful plate solve. I hadn't homed the mount so it was way outside PinPoint's search parameters - Doh! Correctly synced, all seemed well so the system tried to focus on the sync star but failed. Too bright by far - and my fault as the ADU values and exposures were well outside the parameters I had set in CCD Commander (CCD C). Locating a much dimmer star resulted in perfect focus - Doh! CCD C continued to the next stage and slewed to my chosen object and carried out another plate solve this time successfully. Hooray! Sooo, it went in search of a suitable guide star but once it had found one and started autoguiding, I watched in horror as the errors got worse and worse until it lost the guide star completely! Perhaps I should have remembered to tell the control software which side of the meridian I had last carried out a guide star calibration? ..... Doh! The imaging run with autoguiding went smoothly until the pre-programmed autofocus routine came round after about an hour. No suitable star in the field of view - this is why I should be either specifying a suitable mag 4.0 star to slew to and focus on or not being such a tight wad and just buying the full version of PinPoint and not the LE version that came free with MaxIm DL so that a nearby star of suitable magnitude can be located automatically - Doh! Having completed the capture of the data, CCD C closed the automatic flat-flap, turned on the EL panel and started to capture flat frames - I say 'started' because it never actually captured a single flat frame because I had set the slowest exposure to 1 second (to be extra sure of avoiding any masking with the camera's mechanical shutter) and the system calculated that I actually required an exposure time of 900ms to suit the ADU value of 22,000 that I had set - Doh! The cooling system on the camera automatically warmed up slowly to ambient temperature, the mount parked to the north, the dome parked to the south and the dome shutter stayed open for no good reason so I recycled the closing system and it closed beautifully and smoothly - Doh! On a secondary note, although the replacement Pulsar shutter system works extremely well most of the time, there are a couple of things that I would like to have changed for my own rather exacting requirements so I went about designing my own control system which I have since installed alongside the supplied system. This gives me the following advantages over a standard installation:- 1. Because the power to the motor is applied for a fraction longer than the actual travel time, instead of the shutter apparently opening in 1 second (as is the case with the standard command structure), the LesveDome system now issues a realistic (approx 40 seconds) notification to CCD Commander that the dome is either opening or closing. This means that there is no risk of the automation software starting to capture an image with the shutter partly open which could happen if an imaging run started immediately after a dome opening.2. Should I choose to, I can use the ‘stop’ function in LesveDome to halt either open or close commands at any time during the shutter’s travel.3. I get a ‘soft’ stop at the limit switch rather than an instant stop - no big deal, I just rather like to soft close!There are two disadvantages to my modified system:-1. Because of the soft stop, there is a very small amount of ‘coast’ at the end of both an opening and closing cycle that has to be allowed for to avoid the shutter fouling on the dome aperture edges2. To manually open or close the shutter, I now have to hold the switch in the up or down position for the duration of the travel rather than the system automatically carrying out an automated operation as standard. I could simply incorporate a small timing circuit to make this automatic but, to be honest, it really doesn’t bother me as automation rather than manual selection is what I am aiming for.I need some clear skies please and a few less Dohs..............

Yes, I agree, this will require tweaking and as I discovered last night, I may have darkness and wet sorted but I have singularly failed with cloud