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The package was easy to set up and I did read the manual very carefully before first venturing out! However, after two weeks I nearly took the telescope back so thought my experiences might help some others starting with astronomy.

 

Two Star Alignment - Power Supply
My first big learning event was trying to get the Autostar through its first two star alignment - it worked very rarely and often set off on a very long wander of its own never arriving anywhere! I had new batteries (Duracell) in the power clip and tried another set to no avail - only rarely did I get aligned. Manual pointing was usually OK. This problem lasted through several sessions and I had come to the conclusion that I had bought too cheap a package. The motors seemed to be labouring and not consistent. In the end I decided to buy a mains transformer (9volt SMPS, stabilised and fully regulated) and soldered up a connector for the 9 volt Meade connector using an old 9v battery connector fly lead.

Marvellous, immediately the telescope was a new beast and all slewing was carried out perfectly - and it sounded better! I checked battery pack which was showing 9.5v unloaded - but obviously, in operation, the motor drain was high and the battery pack could not cope. Whether as the motors, bearings, etc. get run it it will work off batteries only time will tell. I had to make up a transformer and connector as there did not appear to be one in the catalog that ran from the 240v supplies we have here. (The transformer I have installed also runs with input voltages from 110-240v so I will be able to use it when on holiday in USA!)

UPDATE: After six months of use, always on power supply, I tried the battery pack again .. perfect!! My conclusion is that the motors, gears, etc. have loosened up (been run-in) and are now free and run within the battery pack capability. Running from the battery pack also has the advantage of not getting power cable wound up around tripod during sessions!

North - aligning the Telescope
The next adventure I had was to set the telescope pointing north - I used a compass for some nights and could not work out why alignment was still a major problem. Then, whilst messing about in daylight, what did I notice but that bring the compass anywhere near to the telescope, including in the barrel area, and the compass needle promptly took a dive - the telescope motor magnets are obviously quite strong and produce fields covering the total volume of the telescope. My solution to this was to align a long length of timber placed on the ground against the compass.  I put the telescope in both vertical and horizontal zero positions on the cover markings and then moved the telescope and tripod gradually till the telescope pointed north by alignment with the piece of timber. I then glued penny coins to the ground marking the telescope legs thus establishing my base/starting physical position for all viewing sessions. This ensures a given alignment from start each time.

This has proved to be a miracle. I aligned the telescope using two star process five sessions ago and since then I have used the Menu Utilities/Park command at the end of my viewing sessions before moving telescope indoors. For the next session I just align the tripod to the coins and enter the date and time. Off I go immediately with no further alignment and GOTO producing stars in the field of view with the 9mm eyepiece.

Focus Adjustment
The other fix I have carried out is to put a length of 1/2 inch plastic tubing over the focus knob to allow easier focussing - getting my fingers to the focussing knob was not easy and impossible when the telescope was pointing at objects high in the sky. The length must not be too long otherwise it will foul the base as telescope slews to high elevations. Warm the end of the tubing and it will easy slip over the knob and then remain tight for further use.

I now have a setup with which I am confident. I am able to be up and running within minutes of carrying the telescope outdoors.

Parfocal from the supplied ETX 70AT Eyepieces
I found this tip in Mike Weasner's Mighty ETX site, I cannot give credit to the originator as I cannot find the source again. Anyway, you will find that you have lots of twisting the focus adjustment with the supplied lens when you change from the 25mm to the 9mm (and vice versa). The more expensive Meade range of eyepieces are parfocal which means that when you change lenses the image remains in focus (no twisting of the focus knob). This much improves the whole operation of the telescope and your enjoyment of astronomy. Each time you slew to a new star it becomes easy to swap from 9mm back to the 25mm for much easier location of the new target.
You can make the two supplied lenses approximately parfocal by adding an elastic band to the 25mm eyepiece as shown in the photo to the right. The position of the elastic band is of course key to the parfocal function - the location shown works very well for me. The 9mm eyepiece is used as delivered and slides down to the stop in the eyepiece tube. The band on the 25mm eyepiece prevents the eyepiece completely sliding home - make sure you tighten the securing screw to prevent lens sliding out. This fix has very greatly enhancing my enjoyment of the ETX 70AT - re-focussing each time a lens is changed is not easy and, frustratingly, takes a long time.

Observing the Sun
I got very frustrated waiting clear nights here in the UK through December time, especially as there were nice clear days so I bought a Sun filter. I had read all the warnings in the magazines and books - do not point ETX 70AT at the Sun at all unless you have a good quality filter.

I bought the filter shown on the left from ScopeTronix in Florida, USA. They shipped overseas very promptly. The glass filter fits very snuggly onto the telescope and I am confident it will not slip off. I see from ScopeTronix website that they now have a screw-in Sun filter for the ETX 70AT (which fits the ETX 60AT) which replaces the model I am using.

This is giving me interest during the daytime plotting sunspots and trying to calculate the rotation of the Sun. See my Observations page.

Digital Camera Attachment

I have a Canon G1 digital camera and wanted to use that to capture images through my ETX 70AT.

After a search through the internet I came across the range of Digi-T Digital Camera Attachments from ScopeTronix. 

I purchased one for my camera - the attachment screws into the lens ring on the camera and uses a ring with three screws to attach to any 1.25" eyepiece. You remove the rubber eyeguard and the three screws use the eye-guard slot for attachment. See ScopeTronix site for more details.

The Scopetronix site shows some amazing results with this type of adaptor: my results are not up to their quality - as usual, time and perseverance are required! See images on my ETX 70AT observations page.

Travel with ETX 70AT

I also have an LX90 scope, bought after the ETX 70AT got me caught on practical astronomy. However, I still use the ETX 70AT and it comes into its own as a travel scope. I successfully took the scope across the Atlantic with me on holiday (my wife came too!) with no problem. I wrapped the telescope in bubble wrap and took it in a carry-on bag which went in the overhead locker on the plane. The tripod went in its Meade bag in the hold. All arrived safely and some good viewing was to be had under Arizona skies. Security did not even ask me to open the bag in either direction.

Starry Night Software

I had no problems connecting the telescope to my laptop computer and running the Starry Night software bundle provided with the ETX-70AT package. The display follows the telescope's movement so is always centered on the view through the eyepiece - useful when there is more than one observer around as the other is kept interested. 

The ETX-70AT package seems a very good introduction to astronomy to me - I had been considering much more expensive equipment for over a year but this price level has tempted me in!

 

Beginner's Bits

The ETX-70AT has a 70mm diameter objective (front) lens: this is the lens that captures the light from the stars. The amount of light gathered by a lens is proportional to its area thus a lens of 140mm diameter will gather four times the light (and remember - some of those photons will have been travelling for billions of years before they finally end their journey being captured by your telescope and passed into your eye where their energy gets converted into electricity).

The focal length of the ETX-70AT objective lens is 350mm - starlight is focussed to point 350mm behind the lens.

The magnification of any telescope is calculated by:

Magnification  =  Focal Length of Telescope
                           Focal Length of Eyepiece

Thus with the supplied 25mm eyepiece the magnification is 350/25 = 14 times and with the 9mm eyepiece is 350/9 = 39. The 3x Barlow lens multiplies the magnification giving the 25mm and 9mm eyepieces magnifications of 42 and 117. Note that the 25mm eyepiece with 3x Barlow has approximately the same magnification as the 9mm alone.

Observations

I have also tried to start recording my viewing - click to link to Observations

 

                                                            LINKS:

The site I have found most useful is Mike Weasner's Mighty ETX site.

Night Sky Observer for broad areas of astronomical information

Heavens Above for all the data, maps and timings of satellites - this site is a gem.