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| A little bit of history I've always been interested in Astronomy and about 11 or 12 years ago finally made the plunge and decided to buy myself a telescope. After some investigation I settled on a 6 inch f/6 Newtonian on a Super Polaris mount from a local supplier I'd seen advertising in the then new Astronomy Now magazine. Along with the telescope I also purchased a variety of accessories, fully intending to make observing and photographing the heavens my new hobby. Unfortunately for a variety of reasons (one of which was the difficulty of setting up the tripod in the back garden) things didn't pan out as intended. The telescope was relegated to gathering dust in a spare room. Fast forward to early December 1999 and a particularly dark clear night in the wilds of Dorset and Orion rising majestically. Fast forward again to a couple of days later and The Sky at Night featuring an item on the new generation of GOTO computer controlled 'scopes. This was certainly the item that re-awakened my interest so soon after seeing Orion so clearly just a few days before. In the 10 years since my previous foray the Internet has made research much easier. The Meade ETX 90 and 125 EC models seemed to be covered extensively but it was the Nexstar 5 that was getting the more favorable comments so I decided to order one of those. Just before Christmas I took delivery and the rest, as they say, is history. Why do I like my Nexstar? It takes just 5 minutes to take out the kitchen steps to the back garden and auto-align the scope, select an object from the extensive database and have the telescope slew to center the object in the field of view. It's so easy that in comparison to my previous scope it positively encourages you to use it and in only three or maybe four uses in the past month I've found and seen about 20 celestial objects, probably more that I ever found with the old 'scope. What will I use my Nexstar for? Everything! Piggyback and prime-focus astrophotography, sketching objects seen, computer control and quickcam remote viewing. oh, and looking at things as well if I can find the time! Will I be any good at any of this? Probably not but I hope to have fun trying. 25/02/2000 David Hinds delivered my Nexstar tripod today. The construction is very solid and the Nexstar sits very firmly on it with no hint of a wobble or a shake. At first I thought the three hand tightened bolts for fitting the tripod to the base of the Nexstar were the wrong size as they are very tight indeed. Eventually I managed to force them in but it was a real struggle. I've even had to mark each bolt and corresponding hole with a label to indicate which bolt goes into which hole. I wonder if I created new threads in the holes? Leveling the tripod is much easier than leveling a set of kitchen steps! Just a couple of minutes had the job completed and a couple of more minutes to mount the scope had me up and ready for observing. I noticed that the power lead from my battery pack now has to stretch further as the base of the telescope is higher off the ground - new extension lead required. M48 really is beautiful. The central section with the grouping of paired stars looks just like a glistening necklace. 26/02/2000 Is the Field of View (FOV) with the standard 25mm Plossl eyepiece really 60'? I've had my doubts for a few days because whenever I check my sketches in Cartes du Ciel they always show a narrower field than the software. I've been attributing this to my inexperience but maybe it really is less than 60'? Maplin have an extension power lead at £4.25 + VAT and Postage. Order Code BV47B. Guess what I just ordered! 27/02/2000 I posted a message on the Nexstar email group last night and received some interesting responses concerning my FOV question. It seems the focal length is 1350mm and not 1250mm. The figures are published in the review of the Nexstar and ETX-125EC in the February 2000 Sky & Telescope. That would make the FOV 55' although I still think this is a little high. Read more about it here . The plan to copy Tom Skinner's homebuilt equatorial wedge hit an immediate problem. The Nexstar base has three holes that accept quarter inch bolts. You try and find Imperial measure bolts in metric Britain these days. Correction: Tom has quite correctly reminded me that the bolts are 3/8 inch. 28/02/2000 I've kept very quiet about my first attempts at astrophotography, for understandable reasons. Last month I used my homemade piggyback mount with the Russian manual camera and 135mm lens for the first time. I used Kodak Elite Chrome 200 and took slides of the Pleiades, Orion and Hyades at various f-stops and assorted exposures ranging from mere seconds to 30 seconds. As a first effort I was pleasantly pleased with the results, a couple of the Pleiades slides showed stars down to Mag 10 and one or two of the Orion Nebula region displayed a very nice cherry red "lump" in the middle. Looking at slides is fine but I wanted pictures I could post on the web. Michael Covington's bible for Astrophotographers, Astrophotography
for the Amateur, talks about copying slide film onto finer grained slide
film to increase the contrast and enlarge selected areas. Unfortunately I
could find very few references to copying slides onto colour negative film for
colour prints. One site on the web indicated it was possible so I decided to
give it a try. Needless to say there is something on at least 5 of the pictures and today I received the Photo CD with the proof. Unfortunately Kodak couldn't work out where each frame started so I may have my photos but not the complete pictures. Here is the result. The jury is still out as to whether all the effort was worth it. 29/02/2000 The case I ordered on-line last week from goplaces.co.uk arrived today. Deciding which size of the standard design to get was a difficult choice but I finally chose the 33" x 20" x 16" on the basis that it would take the Nexstar and assorted equipment all at once. Now that I can see it in the flesh I reckon it could probably take the new Nexstar 8 as well. The power extension lead arrived from Maplin. It's roughly 46" coiled and stretches to about 6 feet without too much effort. 1/03/2000 I used the extension lead tonight. It does make slewing a little safer as there is less chance of the lead coming unplugged from the Nexstar. I had a look at M67, M50 and M44 and made sketches of all three. The one of M67 is now on the sketches page. I've still to work out which stars I saw in the other two objects as I'm now convinced the FOV is not 60 minutes but nearer to the 55 minutes mentioned in the February Sky & Telescope. 3/03/2000 The drawing I made of M44 is now on the sketches page. It took me some effort to work out that the marks on the paper did indeed match the chart I printed out. The principle reason for this is that my star diagonal wasn't giving me a truly inverted view with South at the top and North at the bottom but a slightly rotated image with South over in the South East position (does that make sense?). The newbie lesson for today is: make sure your star diagonal and eyepiece are perpendicular with the telescope tube. 5/03/2000 You may have heard of the Nexstar slewing problem. I've experienced it a few times both with the supplied A/C adaptor and with just the batteries installed. Since exclusively using the external power pack from Draper I've not had a re-occurrence of the problem, until last night that is. Whilst slewing to NGC 2129 in Gemini it got to the general area in the normal fast mode and then slowed to fine-tune the co-ordinates. Unfortunately it stayed in fine-tune mode and just carried on slewing slowly in R.A. until I unplugged the power cord. It did a similar thing about an hour later when slewing to NGC 2266 but random punching of buttons managed to clear the problem leaving the Nexstar in Ready mode again. If the uncontrollable slewing wasn't bad enough none of my sketches match what I was supposed to be looking at. I played with the Cartes du Ciel roving eyepiece this morning to see whether I could determine what I'd actually seen, with interesting results. My M50 sketch is centered on 7h.03m, -07.36 whereas M50 is actually at 7h.03m, -08.20. My new sketch of M48 is centered at 8h.13m, -04.50 when it should be 8h.13m, -05.48 Both of these sketches are out by about one degree in Declination but the R.A. is spot on. What's even more interesting is that both these sketches were made after I managed to stop the second slewing problem. 5 further sketches made either before or after the various slew adventures seem to be just random patches of sky - I can't match them to anything! (incidentally, I've never found M50 with the Nexstar GOTO facility. I have three separate sketches made on different nights and they are all "wrong".) I know the GOTO facility works, as witnessed by the sketches I've published, but it's obviously not infallible. 5/03/2000 (later that same day...) I've been pondering the problem of M50 again. It looks like I have found M50 after all! Doing yet another re-check I've discovered the sketches made last night and on the 24th February look remarkably similar. The chances of the Nexstar slewing to the same random patch of sky on two separate occasions must be infinitesimal so I think I must have found M50. Anyway, I've now updated the sketches page, see what you think. 14/03/2000 There is definitely a problem with my GOTO
facility. Last Sunday, after a perfect 2 star alignment using a level
tripod , I slewed to and made 3 sketches: NGC2353, M35 and NGC2505 and every one
of them is After a few suggestions in the Nexstar Egroup I did a
couple of 2 star alignments tonight and then slewed to named stars each time -
none of them were in the FOV. I then did the March Tour and selected the
Beehive Cluster. With nothing (again) in the FOV I checked the
hand-controller and it said it was pointing at 8.40.3m, +19.58' 22/03/2000 Over the past week I've been conducting more tests and sending the results to David Hinds. One test using batteries instead of the external power pack eliminated the slewing problem I mentioned on 5/03/200 but the GOTO accuracy didn't improve. Whilst not quite random some of the slewing to named stars was a little strange to say the least. In one case I estimated the GOTO was out by about 15 degrees in the DEC axis. During the final test yesterday something even stranger occurred which perhaps illustrates how random the situation is: it completely missed all the named stars and M42 but for the first time I found M44 and M36. The sketch I made of M36 is now on the sketches page and I'm working on the one I made of M44. The end result of all this is that I'm now eagerly awaiting a new hand-controller.
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The two best slides
were copied on to Agfa Professional 50 colour print film using my slide
copier, illuminated by the light from the Halogen lamp in the slide
viewer. The film was taken to my local Jessop's photoshop for
development with a request for a Kodak Photo CD. A week later they
were returned from Kodak with the comment "There is nothing
on the film".