New Forest Observatory ®

And here’s the “straight out of Photoshop” version with no added contrast enhancement or saturation courtesy of PaintShopPro.

The very quick “process” I did on the NGC7000 image below was no more than a DPP pass and bolt the two frames together – would have taken less than 10-minutes as I just wanted to see what the image looked like.  I know there’s a bad magenta caste and the bottom half of the image looks like it’s been through a ringer – but I didn’t think that spending more time and doing it “properly” in Photoshop would make much difference – WRONG!!!  I spent around half an hour doing it “properly” using gradient exterminator and some curves and levels and it came out markedly different – much to my surprise.

Another 1-hour image (only 6 x 10-minute subs) from the early hours of this morning.  This is the North America nebula NGC7000 with the Pelican making a cameo appearance on the right.  This time the mount was dithered so not hot pixels – YAY!!!

I’ve had my suspicions for quite a while now, but for some reason after just over 5 years  it has finally jelled in my last two remaining neurons what the problem has been.

From way back when I was imaging with the original Sky 90 (bought from True Technology) piggy-backed on the C11 – I had this bunch of trailing stars in the corner of the field of view.  It looked like polar rotation (or coma) but it wasn’t dependent on the sub-exposure time (even for very short subs) so polar rotation was written off.  I got a reasonable collimation (overall) according to CCDInspector, but there was always this bunch of annoying stars in the corner.  Then I saw Steve Cannistra had a similar problem which was due to flexure in the camera rotator – I did his fix and the problem stars were still there.

Recently I bought another Sky 90 from an Irish astronomer and this went on to the mini-WASP array as one of the two main imaging scopes.  I was able to collimate the M26C to this scope very quickly, and unlike the other scope I didn’t have to really bolt down the adjusters to the metalwork on the M26C to get good collimation.

So after just over 5 years I finally come to the conclusion that the collimation of the Sky 90 itself is way out!!  Luckily this is the model that has the three collimation adjuster screws on the lens cell.  So the offending Sky 90 has now been removed from the mini-WASP framework and is now sitting on its own tripod ready for yours truly to attempt collimating against a star.  Not done this before for a refractor, so I’ll let you know how I get on, and if the problem goes away.

Even though collimation on the second camera wasn’t too good (again) last night, I still took 6 x 10-minute subs of the North America nebula using both cameras and scopes.  I’ll be looking at the data very shortly.

Well here it is – one hour’s worth of data taken with the two M26C cameras on the New Forest Observatory mini-WASP array.  Still lots to be done before it’s properly tuned in – but I’m pretty close now.  As I was finishing this off at 3:00 a.m. this morning I might well be writing a load of rubbish here – but I’ll carry on all the same.  Note this is just 6 x 10-minute subs from each camera – now try and imagine my usual 8-hours plus with the Sky 90.  I’ve left all the hot pixels in the background as I didn’t have the dither function running last night – but I’ll try to have that going on the second outing.  The collimation for camera 1 (the top half of the image) is spot on – the collimation for camera 2 (the bottom half of the image) is off a little and needs to be tweaked just a bit (lousy stars bottom right hand corner).  However – the field of view is as you can see MASSIVE (there’s M29 sitting at the bottom of the frame, check out the FOV on your favourite planetarium program) – and the M26C cameras really seem to be delivering the goods with only a single hour’s worth of data!!  Well done Terry Platt.

As it looks like it might be clear again tonight I’m off to bed for a couple of hours.

It has been a glorious day all day with clear blue skies – and this time it didn’t fog over as soon as the Sun went down.  So I started the final hard bash at getting the mini-WASP array commissioned at 8:30 p.m. and got it to the state where I can start imaging with both cameras and an overlapping field of view at 1:30 a.m.  I am now doing a 2-framer (in one go) around the Sadr region.  The only thing I haven’t got running is the dither which is a bit annoying, but I can probably work around that with a bit of luck.  So – after 4 years of planning and execution the mini-WASP array is finally all systems go.  Must admit I didn’t think that simply doubling up to two cameras and scopes would be so much trouble.  There’s a very good chance that I won’t go the whole hog and build the 4-camera 4-scope array unless I get VERY used to running these 2 cameras – and somehow I don’t think I am going to get THAT proficient.  Still – mustn’t be greedy, a 4 x 3.33 degree field of view at 3 arcseconds per pixel should be good enough to last me for quite a long time 🙂