Equipment

I get quite a few questions regarding the equipment I use for my images, which this page hopefully will provide some answers to. I’ve moved on quite a bit from my initial experiments of trying to attach a Fujifilm compact camera to an eyepiece and the equipment I have now represents my investment over the last two years based on my own experience and discussions with freinds who’s advice has helped me to progress within this hobby.

You are never finished with this though, there exists no perfect set of equipment for all targets and conditions, most choices are a compromise based on your budget. Bad choices when you start out are inevitable, they only thing I can say having made all the normal mistakes is find a society or a specialist supplier, talk to people who do astrophotography and take the time to learn. It’s not easy, it’s rarely cheap, and poor equipment choices will only lead to frustration.

The General Purpose Setup

This is the configuration my equipment is normally in when setup in the roll-off roof shed. It allows me the widest possible range of targets with the least possible mucking about. It consist of the following equipment, see further down the page for more information on the equipment :

• Celestron CGEM Mount on Fixed 6″ diameter pier
• Custom Orion Optics 250mm f4.8 Newtonian Reflector (primary imaging scope)
• William Optics ZS66SD Refractor (guiding and widefield imaging)

The ZS66 is piggy back mounted on the the reflector for guiding, however it also allows me to mount my imaging camera on to it for widefield photographs. If required I could also directly mount the camera instead of the ZS66 to image with a standard lens.

Telescopes

I have two telescopes at present which are used for imaging.

Orion Optics 250mm F4.8 Reflector

This telescope originally started out life with me as a second hand old black tube OO reflector, complete with a terrible two vane spider which was rather industrial in it’s design, a horribly rack and pinion focuser and what I would charitably call a ‘strictly functional’ primary mirror cell. To be fair the instrument pre-dated the rise in popularity of astrophotography but was always an excellent tool for visual astronomy. Once my requirements became more critical the flaws in the design soon became apparent. The two vane spider created extremely nasty diffraction spikes as each vane was about half a centimetre thick. The mirror cell had no locking mechanism and tended to sag and move slightly during use, not enough to bother a visual observer but disastrous to long exposure photography. The focuser just made life miserable for visual or photographic use.

Since I bought it I have replaced everything but the mirrors.

Antares Dual Speed Crayford Focuser – currently costing £129, I think I got mine for £90. This was the first part to be replaced not long after I got the tube and is the one thing I won’t be without on a telescope. It has no issue handling the minimal weight of the Canon 1000D and is very easy to adjust.

Orion Optics 9-point flotation mirror cell – this provides excellent support for the primary mirror and can be locked once your have achieved collimation. My only issue with open tube designs like this is that the camera picks up any stray light coming in from the back of the tube. I still use a tube cap at the back to present this.

Orion Optics Four Vane Spider – A bit of a let down if I’m being honest, The spider vanes are to flexible, the adjustment is crude and the design is from the minimum effort end of the scale. I would have expected something a bit better from OO. It will be replaced at some point with a Protostar spider instead.

Protostar Light Trap Flocking Material - A must have for any Newtonian reflector in my opinion, especially if you have any light sources near you. When combined with a dew shield it will help to control stray light and internal reflections.  My only complaint would be that it’s sticky back tends to fail in hot weather resulting in it peeling off the tube and an annoying job to re-stick it. I would suggest using some better glue to start with.

William Optics ZS66SD Refractor

I bought this little telescope prior to going on a camping holiday in northern Italy back in 2009, I wanted a small portable scope for observing and imaging and at the time this was the one to get in  my price range. Since then it has become my guide scope as well as continuing it’s widefield and travel duty.

If I was going to have one major complaint about the ZS66 it would be this focuser arrangement. It is extremely difficult to adjust it to properly take any weight, it slides out far to easily and won’t rack back in with any ease. Normally I leave it set at the correct focus point for my guide camera as adjusting it is a recipe for frustration.

Here it is in guiding duty mounted on a pair of BS Astro guide rings which I am very happy with, they are extremely sturdy.

Mounts

I have two mounts, one which lives in the roll off roof shed and rarely moves anywhere, and the other which is for camping, nights out with BAS and general visual use.

Celestron CGEM

The Celestron CGEM is basically a modified EQ6, sporting a few mechanical and software changes from that model but carrying all of the same problems. Mostly that it is a) cheap (in the scale of mounts suitable for astrophotography) and b) made in china. So you can expect poor quality control and fairly loose tolerances which result in performance which falls a way off from ‘perfect’. As with the EQ6 anyone with a mechanical frame of mind, time to spare and no fear of a warranty can take it upon themselves to resolve many of the inherent mechanical problems which cause high periodic error and other such concerns.

My primary problem with the mount were electrical connection issues between the handset and mount causing various errors. Re-crimping the RJ connector on the cable cleared up that though and it has been running quite happily for over a year without a problem. The other concern between getting an EQ6 or a CGEM is EQ-MOD, the excellent suite of software tools that allow you to bypass the EQ handset entirely and give far greater functionality to what is a basic mount.

I have found the the CGEM responds very well to periodic error correction, my initial uncorrected error was +/- 14 arc/s which was reduced to +/- 5 with the use of PemPro, something any owner of this mount should do.

Vixen Sphinx SX

Earlier on this page spoke about making poor decisions and getting the wrong equipment. This was mine,and quite an expensive one  it was to. The Vixen Sphinx SX is a medium size equatorial mount with a rather unusual large screen colour planetarium controller. I originally bought it with the thought that it would be my primary mount, a decision with resulted in no end of frustration as I found it’s carrying capacity far to small for what I wished to do with it.

Eventually I purchased the CGEM and the Sphinx found a new lease of life as my portable mount, a job it has proven very capable of so far. Mechanically it is excellent, and a superb match for the ZS66 allowing me to take long unguided exposures of up to 5 minutes without trailing given good alignment.