Show and tell.

*My MkIV Fullerscopes mounting and 6" F:8 Celestron refractor seeing in the New Year 2004 in heavy frost. Look at the rust on those shafts! More on this later.

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I had a couple of Fullerscopes websites from a few years ago which became inaccessible for updating due to two changes of ISP. Agent Orange has now deleted them. I'd like to thanks those who have emailed me with images, ideas and questions regarding their own Fullerscopes mountings after visiting my old Freeserve websites. I thought I'd start a blog on my Fullerscopes mountings to share my progress in restoring and modifying them. The blog format offers great flexibility in updating and a wonderful freedom to post lots of (enlargeable) images completely free of charge.

Why should I bother with two websites and a blog about these 30-40 year-old mountings? Simply because I find they offer a rock solid, reliable, stable telescope support at relatively low cost compared with most of the mountings available today. The modern approach seems to be deliberate complexity and light weight. Usually at the expense of something which shimmers for long seconds every time the telescope is touched or the breeze blows. With axes clamped and drives engaged I can literally thump the telescope tube with my fist and continue viewing without interruption. More importantly for me I can just hold a digital camera up to the eyepiece and take quite decent astronomical "snaps" without visible camera shake. This is lasting value of the solid gold variety but at remarkably low cost compared with many new mountings.

An image of a modern HEQ5 mounting kindly sent to me by an English amateur astronomer. Note the comparison in casting cross sections with the Fullerscopes mountings. What about the skinny legs of the tripod and the even skinnier axis shafts? Then there's the considerable overhang of the Declination casting before it meets the saddle. Where the very short wedge is supposed to carry the entire weight of the OTA and any off axis loads placed on it by the observer or the wind. (OTA=Optical Tube Assembly or more simply: telescope tube) Note the tiny setting circles and the tiny wormwheels hidden away within the tiny main castings. The Meade LXD55 looks very similar in appearance. Ask yourself why it was built this way.

Now look at the solid shafts and castings of the MkIV. Designed to carry the loads properly distributed by the use of carefully shaped conical castings. The tube cradle is 24" (60cm) long and has a massive collar fixed directly to the declination shaft with reinforcing webs running the entire length of the casting. The mounting base is bolted down to a flange supported by a heavy 7" diameter pipe pier carrying the loads and any vibration directly down and into the ground. There are no obvious weaknesses or bottlenecks anywhere in the design. All the loads of the OTA are carried through stiff casting cross sections and heavy shafts. The axes are further reinforced by duplicated 6" diameter flat bearing surfaces to further avoid flexure. The largest cross sections are at high stress points while weight and material has been sensibly saved at lower stress points. The 6" wormwheels literally dwarf those seen in most modern Chinese mountings. Compare the cross sections of the castings.

Which of these two mountings was designed by an engineer with experience in amateur astronomy? Why was so much forgotten about stability in the intervening decades? The MkIV castings themselves actually weigh very little without the heavy shafts. The MkIV mounting could be easily modernised. Possibly by using much larger diameter stepped tubular axes with opposed conical roller thrust bearings (or angular contact ball bearings) for lower friction with considerable weight reduction. (if it was really thought desirable to lighten the mounting to make it more portable) An aluminium pier of similar construction to my welded steel one would save a lot of weight if the equipment had to be stored indoors and only brought out for observing. Lockable wheels and hard surfaces would make any weight reduction superfluous if the pier and mounting were safely housed in a garage. Or the pier pipe cast into a concrete block in the ground with the mounting permanently set up and protected by a secure, waterproof cover. Thereby allowing the amateur astronomer to attach the OTA at a few moments notice and begin observing.

Here's a typical wide-field, hand-held shot of the Moon taken through my 6" F:8 refractor. The digital camera was simply held to the rubber eyepiece shield and the object centred in the camera screen. The camera used here was an old Sony P71 with a tiny screen. The image is still quite pleasing to my eyes. It has simply been downsized in Windows to "Large" from a half meg original size. No other processing was involved. The slight colour on the lunar limb is due to a lack of minus violet filter. From memory the eyepiece used was a dirt cheap 20mm no-name eyepiece. I normally use a cheap no-name 1.25" star diagonal to avoid neck wringing just to be able to see the camera screen. From long experience with this star diagonal I cannot see any difference in image quality compared with not using one at all. I have repeatedly observed the planets and the Moon "straight through". Then fitted the diagonal. I simply cannot see any difference in detail. Perhaps I was just lucky to get a good one. The reason for owning these cheap things was not abject poverty. Just that the distant vendor/wholesaler I visited could not accept credit cards. So my purchases were limited to the cash I had in my wallet!

Here's a typical image example showing the solidity of these old Fullerscopes mountings. The Moon captured with a hand held digital camera simply pointed through a no-name, 10mm Plossl eyepiece fitted into a no-name star diagonal in the focussing mount of a secondhand Chinese 6" F:8 refractor on a 40 year-old MkIV mounting. Not even a minus violet filter was used here as can be seen by the slight overall wash of violet in the shadows. (if you left click for enlargement)

I hadn't even managed to centre the image in the camera so there was also some assymetric vignetting. So I had to crop the image a bit to hide my clumsiness. This is just the price one pays for owning a digital camera with a tiny 1" focussing screen at that time. Close inspection suggests many tiny craters lost in the "grain". How I wish I had set the camera to a higher resolution back in those days. It was just that the Sony took so long to reset after taking a high resolution image that I became very impatient standing there in the cold at the telescope.

This image, for all its faults, speaks volumes for the quality of these rather fast [F:8] Chinese 6" refractors. With more care in optical alignment and better accessories and filters this telescope could be pushed to achieve far better lunar images. Fixing my latest Canon compact digital camera at the eyepiece would no doubt work wonders in improving image quality. I just wanted to show what was possible 5 years ago using low tech on a tight budget without getting involved in webcams, laptops and image stacking software. Or multi-thousand pound/dollar/Euro apochromatic refractors and GOTO mountings for that matter.

If you can afford over £10k for a telescope mounting then surely you don't need to keep moving it? So why make it ultralightweight if it will never move from its observatory or garden pier? Perhaps you are one of those people who like to go to star parties? Fair enough, but most of us observe from our back gardens or yards. Perhaps you can't afford an observatory so set up from scratch each time? This would require considerable enthusiasm for the hobby of telescope equipment assembly rather than observational astronomy. Just waiting for the instrument to cool down would put me off observing in no time at all. Far better to store the mounting outside on an immovable pier and bring the OTA out from unheated accommodation. A couple of minutes from making the decision to go outside I have fitted the OTA into the rings (or wedge) and I am observing or taking pictures. Can you say the same for your own set-up?

Here's a comparison between the MkIII Fullerscopes in the foreground against the much larger MkIV.

I purchased the MkIII mounting first from a gentleman in England. Later I bought a MkIV online from an astronomical society also from England. The MkIV had once carried a large reflector but had been retired and placed in storage. The price I offered and which was accepted was quite modest despite the problems of getting the heavy mounting to me in several large and heavy parcels. I let them keep the counterweights as I could easily make my own to match my own lesser balancing needs. I was delighted to discover that this particular MkIV had variable speed electric motor drives to both axes with control box and paddle. The engraved slip-ring setting circle mounted directly on the RA slow motion worm wheel was a nice feature. The Declination circle is fixed on the rim on an alloy casting. Obtaining originals of these items secondhand would have been a impossible given the considerable age of most of these old Fullerscopes mountings.

All of my 5-year-old Freeview websites have now been deleted by Orange. Those old websites were put together just after obtaining my very own Fullerscopes mountings. I had dreamed of owning one of these mountings since I obtained the first Fullerscopes catalogue back in the late 60s. Despite the hours spent poring over the illustrations and descriptions there was no way I could reasonably afford one back then. I have always had far too many other hobbies so there always seemed to be too many other more pressing demands on my income. I had instead built many different mountings and telescopes (and their optics) over the years. I never did own any astronomical equipment from Fullerscopes. So the original dream had taken all of 35 years to become reality. Obviously I can't have been too disappointed or I would not be writing this blog. If nothing else I have re-discovered the importance of stability and ease of use. Some of my own mountings were anything but user friendly.

Commercial refractors have now replaced my own DIY optics and OTAs. I find them easier to use and rather more likely to be used thanks to their reasonable size and ease of setting up. Anything which stops me sitting at my computer has to be worth making the effort to go out in the freezing cold! I find my refractors light enough to handle and very easy to put away without having to worry about dewing and optical deterioration. I simply leave an eyepiece in the focussing mount and leave the telescopes standing on their noses in secure but unheated accommodation. The OTAs are often put away plastered in ice or heavy dew. Fortunately refractor dewshields are usually large enough in diameter and tough enough to offer plenty of stability provided one doesn't own a cat, a dog or a toddler with access to the telescope storage area. Cat's have a habit of rubbing themselves against anything they pass. I wouldn't trust a free-standing refractor to remain upright after a brush with our feline friends. I suppose suitably-sized, hinged tube rings could be screwed to the wall to support the top end of refractor OTAs in complete safety. An eyepiece should always be left in the focussing mount to stop dirt and dropped objects from gloing straight through the open draw tube.

A slight downside of nose-down storage of refractors is that the back of the lens may accumulate dust and condensation over time. Focussing mounts are rarely perfectly sealed. Usually the objective cell is screwed onto the main tube though it often takes some considerable effort to separate the cell and tube. Don't use gripping tools or you'll ruin the finish or damage the telescope.

It is not recommended that one remove the glass objective itself unless one has considerable experience and the knowledge to do it properly. It is all to easy to get the glass slightly twisted in the cell. Then to break large chunks out of the vital, precision optical surfaces in the struggle to remove the glass. Far better to use soft tissues to gently clean the exposed lens surfaces as the glass sits safely in its cell.
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