I don't have space for a permanent observatory but if I did, chances are the local chavs would break in and steal or smash stuff up anyway, just because they can.
Setting everything up from scratch for an imaging session is quite time-consuming, and so I built a mobile platform that supports the mount and houses the power supplies for the drive, the CCD camera, the laptop and dew heaters.
The mount and pillar assembly is held onto the top of the box by a stout spring that runs down the tube of the mount pillar and through the top of the platform. This allows some levelling adjustment via the pillar legs but holds the pillar in place firmly enough to stop it moving about during movement of the platform.
The plaform fits on a dolly (see above) that is rolled from my (alarmed) garage to a hard-standing platform at the bottom of my drive, which offers a reasonable south-facing view and which is also fairly well sheltered from street lights and neighbour's security lights. The platform slides off of the dolly and on to the hard-standing area (both are fitted with plastic furniture runners). Once I've got the platform box in place, all I have to do is plug the box into a mains extension, do a polar alignment on the mount and then fit the 'scope, and I'm ready to do my alignments with the "GoTo" Skysensor.
The platform has some locating bars so it goes back in roughly the same place each time, but I use the polar alignment scope in the GPDX to get a reasonable polar alignment that is usually good enough for the 2-3 minute exposures I usually use with the 600mm refractor. I can get away with up to 90 second exposures with the VC200L without noticeable star-trailing if I run the Skysensor PEC, sometimes more if I get lucky with the polar alignment.
Setting everything up from scratch for an imaging session is quite time-consuming, and so I built a mobile platform that supports the mount and houses the power supplies for the drive, the CCD camera, the laptop and dew heaters.
The mount and pillar assembly is held onto the top of the box by a stout spring that runs down the tube of the mount pillar and through the top of the platform. This allows some levelling adjustment via the pillar legs but holds the pillar in place firmly enough to stop it moving about during movement of the platform.
The plaform fits on a dolly (see above) that is rolled from my (alarmed) garage to a hard-standing platform at the bottom of my drive, which offers a reasonable south-facing view and which is also fairly well sheltered from street lights and neighbour's security lights. The platform slides off of the dolly and on to the hard-standing area (both are fitted with plastic furniture runners). Once I've got the platform box in place, all I have to do is plug the box into a mains extension, do a polar alignment on the mount and then fit the 'scope, and I'm ready to do my alignments with the "GoTo" Skysensor.
The platform has some locating bars so it goes back in roughly the same place each time, but I use the polar alignment scope in the GPDX to get a reasonable polar alignment that is usually good enough for the 2-3 minute exposures I usually use with the 600mm refractor. I can get away with up to 90 second exposures with the VC200L without noticeable star-trailing if I run the Skysensor PEC, sometimes more if I get lucky with the polar alignment.
The lap-top sits on a roll-out shelf for ease of access (see above)
I do have a guide camera but to be honest I've never found the time to optimise the settings for it. Maybe a job for this summer.
If I get a good three-point alignment, I usually slew to the chosen object for the evening and then ask the Skysensor to find me a nearby brightish star for focussing and accurate alignment. The SXV-H9 software has a nifty little screen that allows you to sample every second for focussing, and I simply adjust the focusser manually until I see the sharpest possible star on the laptop screen. When I've focussed, I use the image on the screen to track the star while I run the PEC programme. I can then use the GoTo function to send the scope to the object. It usually falls on chip first time.
I take a few shots in 3x3 binned mode, with the minimum time needed to show the outline of the obejct in question. That allows me to accurately frame the object before I start acquiring frames for imaging purposes. I run a few long exposures to see how long I can get away with before star trailing sets in, and set the camera to acquire maybe 50 or 60 raw frames. Often as not 2x2 binning provides adequate resolution for most objects, although I'll always go for full resolution if the object is bright enough.
It usually takes about 45 minutes from me deciding to start imaging to actually starting.
My drive is gated and so I usually feel comfortable with leaving the equipment to do its stuff, if I'm not out there actually observing visually with my other scope (I have a CG5 manually operated mount that I use for visual work).
I never bother with dark frames as the SXV-H9 camera doesn't generate much noise - I usually take out the few noisy pixels there are with a median filter during processing. I take flats after I finish imaging - I wheel the whole set-up back into my garage, point the telescope at a large square of white polystyrene sheet fixed on the wall and take 16 flat frames. I also shoot the same number of flat darks. The garage lights seem to light up the sheet pretty evenly and the flats come out with no visible gradients once they are all dark subtracted and averaged.
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