Missed It By Thaaat Much…

I’m home in Ottawa, confined to quarters by the covid quarrantine but last night was clear so i got out in my side yard for a look. I haven’t go my mount set up but I wanted to see if i had a clear enough view of the pole to do alignment. I would say no problem – polaris is high enough in the sky to stay well clear of houses and i have a decent view between my house and my neighbour’s.

I figured i was aimed close enough to polaris to get it in my field of view but nope. NGC3172 in the bottom right is the charmingly named Polarissima Borealis – it’s not really visible in my image but i still like the name.

I’m looking forward to having the mount set up. I still won’t be able to do a multi star alignment but i had good luck finding things in florida just based on solid polar alignment. I suspect Polarissima Borealis is hopeless because it’s small and faint but there are a bunch of galaxies in the general area M81, M51, M101 should be in easy view.

UPDATE: After much poking around I identified the reddish star to the right in my image as OV Cep – a 5th magnitude star. The dimmest stars are around magnitude 10-11. Seeing was quite good and my focus is good. My image was taken at ISO 1600 for 3.2 sec at f/4 using the Takumar 200mm lens on the Canon t3i. I’m pretty happy with the lens and it’s about as much power as i can handle.

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Polar Alignment With Pictures!

PhotoPolarAlign

I found a brilliant polar alignment program. You put the camera on the mount and align as well as you can. Then you take two pictures with the camera swung 90 degrees around the polar axis. The software uses plate solving to analyze the two images and tells you how to adjust the mount. It takes me a few iterations at a minute or so each but the results are great – Getting within say 5-10 arcminutes is pretty good but with this process i can get to <1 arc minute – 1/60 of a degree! Last minute I was shooting 3 minute exposures at 200mm with no star trailing.

A couple of caveats: The script is written in Python 2 which is obsolete and i had to poke at it a bit to get it working; It depends on downloading the cygwin software to run the astrometry software on windows which is also unfamiliar. The best info i found was in a forum post started in 2014.

Woohoo – Now We’re Tracking!

I had a bit of a debacle the first time i tried the ioptron skytracker – i had no luck at all with the polar scope and i just roughly aligned it with the bore hole.  I had the brilliant idea to roll up a sheet of paper to stick in the sighting hole which let me find and center polaris and then i was able to graduate to their polar scope.  iOptron makes an app that gives you these little pictures of where polaris should be in the reticle – it seemed loony to me but i was actually able to line it up pretty much spot on.

I was working in a cramped spot with no good view of the sky so my reward was this nondescript image of part of ursa minor and draco with zero trailing that i can see.  These are fairly close to the pole but I think they would have shown some trailing in 30 second images. These were taken with the Canon t3i, f/4 ISO 400.
19-9-17 woohoo 3894

I’ll get out into the country and try my luck on M31 tonight. That’s much more likely to smear but i’m optimistic. I need to get much better at pointing the camera once it’s on the mount and i need to remember to focus both the camera and the reticle before i start. it’s interesting to note that it makes very little difference in sighting whether i have my glasses on or not!