The Canon 200mm prime lens and the Canon 5D MkII DSLR were put to good use a few days back grabbing a massive (10 x 6.8 degree) wide-field around the Cocoon nebula in Cygnus.  Using ISO 400 and f#4.5 with an IDAS filter I captured 21 x 4-minute subs with the DSLR and guided using the SX guide camera on a small refractor – all piggy-backed on the C11 which is now groaning under all the added weight.  Further Hyperstar III data of the Cocoon region alone was added to the DSLR template by Noel Carboni who created the final composite using Photoshop and his Astronomy Action Tools.  The Hyperstar III data set was taken a couple of years ago and comprises a 3-frame mosaic with each frame being around 3-4 hours total exposure time using 10-minute sub-exposures.

This combination of using the DSLR to create the wide-field star-field template, and then filling in the nebulosity and faint stuff with either the Hyperstar III or the mini-WASP looks like a winning combination.  The only problem is that the images only look impressive when printed out BIG – all the detail gets lost in A4 size or smaller.

This is a composite image combining the recent 8 x 20-minute subs from the Hyperstar III with earlier Sky 90/M25C which incorporated H-alpha and OIII narrowband data.

Taken with the HSIII on 04/07/2013 this is an S-type star, SAO 69360 in Cygnus.

There was a fair bit of thin high cloud wandering over last night (as it turned out it didn’t get in the way of Cygnus) and so I only set up the Hyperstar III and didn’t run the mini-WASP array.  I hadn’t looked at the framing of this one carefully and centred SAO 69116 in the centre of the HSIII field of view – forgetting that I had the chip in portrait mode rather than landscape mode.  Ooops – that meant that I only just got the edge of the Tulip nebula in the frame  Never mind, I’ll take the second frame another time.

So I’m spending a couple of hours imaging in Cygnus with both the mini-WASP array and the Hyperstar III

For the second test of the newly aligned M25C camera on the Hyperstar III I chose the Stephenson 1 region of Lyra.  Although I didn’t have the optics spot-on they were pretty close and I’m quite pleased with the resulting image.  When I spend a little more time getting the collimation just right we’ll be back to the earlier high-quality Hyperstar III imagery we’re used to seeing

Recently imaged M57 as a test-shot for the recently flattened M25C chip.  This is 14 x 5-minute subs with a blazing nearly full Moon overhead.  Looks pretty reasonable considering

The Hyperstar III is so fast that all other amateur imaging systems are extremely slow and have very disappointing performance in comparison – and that includes the mini-WASP array as currently configured.

Bit embarrassed to say that I am still learning how to use the Hyperstar III.  Rather humbling when I thought I knew all there was to know about getting the best out of the Hyperstar.  I had done a few camera swaps on the HSIII and I was having difficulty getting good stars across the whole of the M25C, something I had not had a problem with before.  Now here is where I was going wrong.  I thought that I could have the M25C adjusters set so that the face plate was perpendicular to the camera body (this means the chip would almost certainly not be flat to the optical axis) and that I could sort out all the chip flatness/collimation with the Hyperstar III adjusters alone.  THIS IS WRONG!!  I slowly caught on that I was not going to get good stars across the chip using the HSIII adjusters alone after spending around 3 hours playing about chasing my own tail – it was clear that the HSIII adjustments were not enough – YOU NEED THE CAMERA TO BE FLAT TO THE OPTICAL AXIS BEFORE IT GOES ONTO THE HYPERSTAR III.  Oh well – live and learn.  So I used Terry Platt’s method as given on his website to flatten the M25C APS-size chip to the optical axis, and I put the camera back on the Hyperstar III last night.

I ran the FocusMax autofocuser on Sulafat (Lyra) and the first 20-second sub looked pretty good without touching the Hyperstar collimation adjusters.  A CCDInspector look at the sub gave me the magic x = 0, y = 0 for the chip flatness (can’t do much better than that), and it gave me 2.7″ for the collimation.  I have never seen a set of CCDInspector numbers this good before for the Hyperstar III/M25C combo.

Hopefully I’ll be turning out some interesting Hyperstar images once again in the not too far distant

Noel Carboni combined the Hyperstar III and mini-WASP data for this image.