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The digiscoping adaptor had arrived a week earlier but I had no chance to use it until tonight. I carried out my 6" F:8 Celestron refractor and put it on the MkIV mounting. The drive box was attached and connected to the mains. After a quick peek at Venus and a quick but poor "snap" I concentrated on Jupiter. Which was very bright and quite high overhead to the South at about 50 degrees altitude. It traversed above the roof of my house as the evening wore on.
Having centred Jupiter I clamped the drives and started playing with the digi-scoping adaptor. I used a 2" star diagonal throughout. The MkIV had to be dragged across the lawn to be able to see Venus. So it wasn't more than roughly aligned on the Pole. It was also well out of level. This meant that the mounting did not track Jupiter as well as usual. Small adjustments had to be made to recentre it at regular intervals.
While it seems like a logical design and has adjustments in all planes the adapter is not at all easy to align properly. The camera lens and eyepiece should be on the same axis and as close to each other as possible when extended. The camera should also be firmly clamped and square to the eyepiece. Not an easy task in practice.
Short eyepieces have no length to mount the rather broad eyepiece clamp. The clamp is padded to avoid damage to eyepieces. It should be admitted that the adapter is primarily designed for use with spotting scopes. These tend to have longer eyepieces compared with astro telescopes. Using a Barlow lens allowed longer eyepieces to be used but with higher powers. So there was no real disadvantage.
The camera must be mounted on the rather slippery, perforated plastic support plate. While simultaneously placing the lens at the correct distance from the eyepiece. A sheet of rubber glued to the top surface of the camera support plate would probably help here. Though it was not difficult to lock the camera firmly once it was finally aligned.
There is a danger that the leverage provided by the adapter, once clamped, will unscrew an eyepiece barrel. This occurred a number of times.
The adapter slide adjustments are rather sloppy too. With the vertical adjustment particularly difficult. Because the adjustment wheel is blocked by the adapter casting foot. Had the wheel been larger this would not have been such a problem. I shall see if I can't modify this aspect of the adapter by fitting a larger wheel. I'm not sure it can be dismantled.
A locking knob at the back of the adjustable slides is supposed to clamp the lateral and vertical adjustments once the camera is centred. I found that this tended to put out the adjustments already made.
In the end, I used a white wall lit by an outside light to centre the out of focus, bare eyepiece circle in the camera screen. Then locked the adapter slides with the knob. Further adjustments were then made and the adapter relocked. The adapter was then carried complete with camera and 20mm eyepiece to the telescope.
However, once the adapter is in place one can no longer look through the eyepiece! If I took off the adaptor assembly complete with camera and eyepiece I could not guarantee something hadn't moved in the meantime. Or the planet had drifted out of the field of view! After some fiddling, I found it best to remove the eyepiece complete with camera and adapter. Another eyepiece was then substituted in the focuser until the planet was properly centred. Had I set up the mounting properly I could have saved some time.
I spent quite some time trying to find Jupiter on the camera screen. Eventually, I lifted off the adaptor assembly (as above) and then centred Jupiter in a wider angle eyepiece. Back on with the adapter and clamped eyepiece and still no sign of the planet on the screen! Eventually, after a lot of nudging the telescope I found the bright dot and could keep it centred. I had previously adjusted the finder telescope to ensure it was on axis with the main telescope.
The problem was seeing whether Jupiter was on the unlit cross-hairs. I am not a great fan of the sprung mounting on the 9 x 50mm finder. Though optically it seems very good. I have several small astro refractors of 60mm and 70mm aperture which could be fitted into home made finder rings with a good stand-off distance. Not to mention further forward of the eyepiece than the supplied finder. Having the finder and telescope eyepieces in the same plane is often a real nuisance when using a star diagonal. They always seem to get in each others way!
First I tried the Panasonic Lumix TZ7 camera. Results were not very good at all. I tried various eyepieces and degrees of camera zoom. Back indoors with the images copied to Picasa 3 I was rather surprised to see how many stars I had captured! The planet itself was an overexposed blob with 3 moons visible! The camera is capable of Ev adjustment but I'll try that another time.
Then I tried my old Sony P71 camera. I had more luck with this but the results are still hardly worth sharing. The resolution is much lower and cropping to increase image scale only exaggerates the graininess. The Jovian moons were soon lost with the slightest adjustment of contrast or gamma.
These are two of the best images from the P71 but are still barely recognisable:
The adapter obviously needs some practice to make the most of it. The Moon would offer a far better target for such practice. But it doesn't rise until much later tonight. Being a morning object at present.
I'm really not too disappointed with the digi-scoping adapter. It held the camera still and on axis far better than my usual hand-held efforts ever could. I would often take 50 shots hand-held and discard most of them due to off-centre flare. Once the planet was centred in the camera screen on thr adaptor I could easily adjust zoom and focus. The MkIV then kept everything nicely still while I snapped away. No need for a camera, cable release with the massive MkIV on its very heavy pier.
I think I'll go back out now and enjoy some casual, visual observing instead. Orion was quite low in the South East but well worth a look at the nebula with various powers. It seemed very clear with wings and indentations. The Trapezium was easily seen. Thought the stars were not particularly small or round. Some adjustment to the telescope alignment may be due after stripping it down to clean the back of the objective. I tried my Cheshire alignment eyepiece but there wasn't enough light to see anything useful.
I stared at Jupiter too with every eyepiece I had in the box but couldn't see much more than two broad, rather smudgy belts. There was no real detail at any power. My feet were getting rather cold by 10pm so I packed everything away.
Click on any image for an enlargement.
