Observatory Fitout

Introduction

So what do you need to setup an observatory capable of undertaking scientific research? Well that's a difficult question to answer as it depend on what you want to do and what level, if any, automation you require. What I will describe here is the fitout for my own observatory.

Telescope(s)

Obviously you need a primary telescope. The larger the better I say - buy as big as you can afford, manage and maintain (don't forget that last one). If you are doing CCD imaging with a scope that doesn't track perfectly well then you'll need to guide it - and I use a separate guide scope. It will need a focal length that will allow it to accurately guide the primary scope. Since I have my 14" at f/4, the 4" guide scope is set up at a little over 2/3rds the focal length. Anything less and you are wasting your time.

Some say you can get by without an accurate GOTO capability, but that's a bit difficult in many cases when the objects you are chasing are many thousands of times fainter than the eye can see.

Camera(s)

You need a means of recording what you are observing. There are a huge range of cameras available out there from the cheap to the very expensive. If you want to take research grade images of faint objects then you will need to buy a quality camera and for reliability of ones data you need some basic features.

In 2006, the MX516 was replaced with a second hand SBIG ST-9E to supplement the ST-8E. The 9E has second stage and water cooling allowing me to cool the CCD to sub -15c even on the hottest summer night. A real boon when those hot pixels conspire to ruin a nights photometric run.

CCD Temperature:	The cooler the CCD the lower the noise and the lower the noise the fainter the object and the higher photometric precision. The second part of this requirement is the ability to set and maintain a fixed CCD Temperature. Many cameras offer cooling but it is cooling to a certain level below ambient. Most observatories will experience largish temperature drops over a single night and any temperature differential over 5°c will generally mean the a new set of darks. Its not impossible to manage but it is very tedious and you have to be on the ball.
Self Guide:	Many Cameras are capable of what is commonly referred to as Self Guiding. This means that the camera itself can take the main image and guide the scope simultaneously. SBIG cameras are fitted out with a second CCD chip to perform this function whilst Starlight Xpress Cameras use an interlace chip that allows the main image capture on one frame and the guider image capture on the other frame. If you do not have a self guiding camera then you will either need a very expensive telescope mount of a separate guide scope and camera.
Connection Type:	Connection types offered range from proprietary (as per some earlier model Apogee's) to Parallel and now USB or ethernet. Modern cameras use USB 2 or Ethernet as it offers the quickest possible download speed for what are not Large CCD chips. A BIN 1 ST-8E image at 1500 x 1000 pixels takes a good 3.5mb and 54 seconds to download to the controlling PC via a Parallel connection but only 4 seconds via USB2. If you are chasing very fast moving objects via Track and Stack then the parallel camera just won't cut it. On the other hand if you are doing lightcurve work then the parallel option is just fine.
Filter Holder:	A Filter holder is a must (well anything that will carry a filter in the lightpath to the CCD). Ideally you will get an automated one as there are issues surrounding manual ones. Manual ones mean that you cannot operate the observatory remotely and in some cases require the scope to be moved, the camera removed and the scope repositioned and/or refocused. If you are taking pretty pictures then you will need to carry Red, Green and Blue Filters. If you are doing photometry then you will need access to Red, Blue, Visual and IR filters (note that these Red and Blue filters ARE NOT the same and the Red and Blue filters in an RGB filter set.)

Don't think for one minute that you will be able to use one camera for all situations. As you can see I have a large range of cameras that have different uses. Start small (as your budget allows) and build up to it.

Scope and Camera Control

Now that you have your scope and camera you need something to control them with. My setup allows for remote observation so I have a dedicated PC located in the observatory connected directly to the Scope, the Cameras and the guider relay box. But this is just the hardware connection. To get it all running you need software - and the software that suits your setup and type of observing.

Observatory Control:

ACP4: S+ AG AF+
by DC3 Dreams is an ASCOM based package that comes in a couple of variants based on your type of setup. I use the basic license that allows me to control the observatory from a single PC. The advanced variant allows one to setup and place ones observatory onto the internet so anyone can use it once they have logged into your site. Note that this software requires the following additional software: MaxIm DL/CCD, Pinpoint 4, FocusMax

MPO Connections: S+ P+ AF-
by Brian Warner is one of the very few software packages actually written by someone who observes - and it shows with a superb interface and everything one needs at your fingertips. The only downside (for me) is the lack of support for a wide variety of cameras.

MaxIm DL/CCD: S+ I P+ AG AF+
by Cyanogen is really a camera control and image processing package but does have scope control and scripting facilities. If you have scripting/programming skills then you can probably get this package to do all that you need of it.

AstroArt: S- I P- MG
by MSB is a camera control package that is starting to spread into scope control. It has some basic scripting options but no automated features as yet. By the way, at the time of writing, this is the only package that offers 100% reliability with Starlight Xpress Cameras

Session Planning:

AstroPlanner:
by Paul Rodman is a wonderful package designed specifically for planning observing sessions and recording observing notes. I use it to plan my observations only as it provides a great tool to observe the relative location of the targets in relation to the sky, moon, observatory horizon and each other. It also provides a detailed FOV tool to determine if the object is well placed to be observed (ie in relation to other objects - no point observing a MP if it will be playing cat and mouse with background stars all night.)

Measuring Images:

MPO Canopus:
by Brian Warner is nearly the standard package for Minor Planet Lightcurve work. It performs image calibration and measurement as well as offering tools for differential or all sky reduction and a period determination and plotting tool. Nothing compares (except perhaps Dr Petr Pravec's own application)

Astroplanner:
by Herbert Raab is the standard in Minor Planet Astrometry. I don't think anyone uses anything else (except perhaps the professional observatories)

MaxIm DL/CCD:
by Cyanogen is a jack of all trade type application. It does the basic image calibration job but also has features for image repair as well as all the tools for processing 'Pretty Pictures'. It has a inbuilt Blinking, Astrometry and Photometry tools as well. I have had the Blink and Astrometry tools working but never figured out how to use the Photometry tools.

AIP4WIN:
by is an image processing package that offers a lot of great features. It's the best tool I know of for creating reliable Master Darks and Flats from raw images and it also has all the basic measuring tools. This application also has the best image editing facilities I have come across allowing the user to remove stars and still keep the image usable for measurement. This package is very easy to use for Variable Star observations and image measurement.

AstroArt:
By MSB has image processing tools and image measuring tools but, and it's a very big but, they are either cumbersome to use or produces images that are not readily usable in other packages. One thing that it does have going for it is a free third party tool that generates very good quality FLATS from a given image. In fact I think it produces superior results to MaxIm's Flatten Background tool.

Muniwin:
My introduction into MicroFUN lead me to this free piece of software. A very powerful photometric tool for variable stars in particular.

Guide to features
S+	Advanced Scripting
S-	Basic Scripting
I	Image Processing
P+	Automatic Plate solve
P-	Manual Plate Solve
AG	Scripted Autoguiding
MG	Manual Autoguiding
AF+	Advanced Autofocus
AF-	Limited Autofocus

Weather station

For years I considered buying one but could never justify the cost. If I wanted to know the weather I only need to pop my head outside and look. Well I'm damn glad I did buy the station - and here's why.

Rolltop observatories are very susceptible to wind. It used to be that I would go out at the start of a session, see that the wind felt too strong so didn't bother opening the observatory. Since I installed the station and monitored the wind I found that more times than not that if the wind was blowing it would generally quieted down or stop about an hour after sunset. I also found that my observatory was capable of operating in about double the wind speed I previously though possible. (I did have a handheld Anemometer I used to measure borderline nights with.)

The station shown here is a LaCrosse WS-3600 (WS-3610 in the states). It operates wirelessly and the base unit connects to a PC (with supplied software) that will also let you share the weather information over the net. You can see my weather on CWOP or WeatherUnderground

Dew Heater

A 14" corrector plate is a huge dew magnet. A high wattage dew heater by itself is sufficient on light dew nights or in a light breeze but on nights of heavy dew there is not option but to use a dew heater and shield.

I couldn't see the point of paying $200+ for a commercial heater when for $30 of easily available material and about an hours effort I could build my own. There are plenty of designs available on the web so I won't go into detail here but I will say that mine comprises 4 straps of nichrome wire each attached to a switch so I can vary the wattage. My dew shield is just a piece of sleeping bag/camping ground foam cut to shape and joined with some velcro tape. These 2 have kept me operating even when the dew is so heavy that it forms a continuous dribble off the scope tube and water puddles form on the observatory floor.

● Email Me: higginsdj at bigpond dot com ●