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By John Lawley
Hi - I've not posted here before as only just launched into this hobby, although I've always been massively interested in astronomy.
I had first light on my rig last night, which is:
Esprit 100, HEQ 5 Pro, ZWO EAF, ZWO mini filter wheel, skywatcher 50ED guidscope with ASI120, ZWO1600mm Pro, Lynx dew controller w 2 astro zap tapes
A big endeavour to get that lot working from zero experience, but I love a challenge and have really enjoyed the computer side (I'm a grade A nerd)...
So - what went well... I got the guide scope in focus (was stressing about this), and also the main scope. Even more awesomely, the autofocus routine in SGP is working perfectly Filter wheel also working perfectly and I'm getting lovely smooth pics from the main camera (I've already done the flats and darks while I was waiting for clouds to clear). Final good thing (well, good-ish), is that I got the platesolving working eventually, and was able to get the scope to align from Park to the Soul Nebula and centre fine. For some reason the "number of attempts" in my SGP profile hadn't applied, so it was giving up after 1 go, but I got it working in the end.
So the bad...
I couldn't take any data because every time it finished the platesolving and started PHD2, PHD2 would start the calibration process and then halfway through, the sidereel tracking on the EQMOD panel would turn off. Obviously, that would lead to a "lost the star" error. Is there some reason why sidereel tracking would turn off like that? I'm generally a bit confused as to whether I should be controlling the telescope from SGP (i.e. unpark) or using the park and unpark + tracking button on the EQMOD panel. Both PHD 2 and SGP are setup to use EQMOD ASCOM HEQ5/6?
So at the moment I can't do anything, because there's no way of guiding without it turning tracking off
Also I was cold. Very Very Cold.
From AST Optics selling my mini guiding system that i used for my Redcat51 , i have used it also with my Esprit 100 and had excellent guiding results.
There is a nice review here if someone wants to read :
Lens: f=100mm F3.5 CCTV objective - made in Japan
Adjustment: by ballhead - with reliable clamping
Dovetail: compatible with most finder shoes
True field of view: 2.9° x 3.8°
Maximum guidable focal length: 1000 mm
Focusing: via lens cell
Connection to camera: C-Mount
Lens filter thread: M30.5mm P=0.5
Weight: 79 grams
Length of the objective: 44 mm
PRICE : £100 (selling the mount and the CCTV lens not the camera)
Paypal accepted buyer pays the fees
I will cover the postage expenses
I have recently bought a Orion Starshoot Autoguider. I downloaded phd 2, eqmod and ascom stuff. After a small research I found out my mount (exos 2 gt) doesn't support computer acces without firmware upgrade and fancy cables but I have the st4 port so it shouldn't be a problem. In phd I choose camera as Starshoot Autoguider and mount On-Camera. Aux mount and AO are both none. My wiring is one cable to pc from camera and another to st4 port from camera. When I started looping I selected the star with no problem. I choosed the one star alignment option from my hand controller and after centering the Archturus in the middle of view I pressed ok and it was successfull. I started guiding and after a while I get the error: RA calibration failed star didn't move enough.
I have some sad news, sad for me anyway, but unfortunately during the final night of imaging my last DSO, the Fighting Dragons in Ara, my CGEM blew up.
At about 4 am, I went outside to check on the imaging progress and decided to dim the laptop screen but accidentally hit the "sleep" button instead of the "DIM" button. Usually this shouldn't be a problem.... but when I "woke" the computer up, the CGEM stopped tracking. Not thinking like it's a big deal, I tried to re-center the object and guide star and this is when I realized that there is something seriously wrong as the mount was not responding to my computer or hand controller commands.
When I power cycled the mount and hit a RA button, the mount moved, it moved at full speed until the OTA and camera almost hit the peir.... the only way to stop it was to cut power to the mount.
Power cycling it a few times did not change anything except that the mount stopped responding in RA completely.... note that the DEC function works as normal.
The hand controller is working normally and not reporting any NO RESPONSE error messages either.
I went on a fault finding mission and tried a different Hand controller with no change than I opened the CGEM and swapped the RA and DEC motors on the main motor control PCB to determine whether I burned out the motor.
With the motor connectors swapped the mount moved in the RA axis and worked properly by pressing the DEC buttons but now the mount is not moving in DEC, so I knew that the motor is not burned out, but the Motor Control board is faulty, possibly the RA encoder/controller chip.
I tried to re-flash the MC Board firmware, hoping that it's possibly just a corrupted data in the EPROM, but after a successful firmware flash, that did not change the situation.
With is information, I need to get a replacement motor control board, and this might take a while to arrive from the USA... so until that moment I will have to return good old observational astronomy using my 14" Dob and imaging will have to wait for the future.
I guess I'm lucky in a way that the failure happened toward the end of imaging my last image, in that last hours, instead of in the middle of it, so at least I ended up with an image.
My theory why this has happened:
I don't think that accidentally sleeping the laptop caused the mount to fail, at least not the act itself... of course, there is a possibility that it's just long term use and eventually everything fails, since I had the mount for 9 years, and it did do a lot of tracking hours... BUT than again it did work flawlessly for all of this time until soon after I started experimenting with PEC, and I had PEC running when this happened.
Could it be that PEC in the mount was trying to move the RA axis in one way, and PHD2/GPUSB tried to move the mount in the opposite way, causing some kind of conflict, or short circuit like/excessive current drain event? perhaps not in general use with quick pulse commands, but when I did sleep the laptop, could it be that GPUSB was stuck in nudging the mount in one direction, and than PEC tried to move it in the opposite direction and that state was held for long enough to burn out the encoder or controller IC?
Either way, comparing PEC programmed mount on PHD2 guiding accuracy to no PEC accuracy, the results are so close that PEC might not even be worth the hassle, and PEC is more useful for unguided imaging?
I think that when I fix my CGEM, I might stick to NON PEC autoguiding since, like I found, PEC is no, or very little, improvement, such a small improvement that the reason can be caused by just the atmosphere becoming slightly more still within the comparison time... accuracy difference of only 0.02-0.05" arc sec RMS.
Thanks for reading and of course thoughts, opinions and experiences welcome.
Ok, so this is a really annoying bug / problem that I have with my setup:
From time to time, in non regular intervals the image my guiding cam (ZWO ASI120) send seems to get flipped / mirrored or looks like it's from a completely different patch of sky.
When I'm paying attention to the guide images I can clearly see that the image seems to be flipped in some way.
It only happens for 1 frame PHD send a warning ( No star found / Star lost Mass changed) and after that everything is fine again. My gear is all connected to a single USB3 Hub which then runs via powered USB3 cable to my Pc.
I'm not binning and have the noise reduction off (though PHD might got hickups while processing) but it still happens. Sometimes there are minutes between two events sometimes it happens 5 times in a row.
It also seems like it's only happening during guiding, I haven't seen it happen during calibration yet...
I'm completely clueless what's happening or how to get rid of it, any help / idea is greatly appreciated.