November dew

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A first clear night for ages pushed me into having a look at a rapidly rising Jupiter in the East. The brilliant full Moon was hanging nearby slightly further to the north east. It was so bright I had no need of a torch when selecting eyepieces from my box.

I had to drag out the massive, welded stand supporting the MkIV. The wheels had sunk into the lawn since the last time I was observing. The pier legs are too big to allow the car to turn safely. So the whole thing has to be pushed out of the way each time I pack up for the night.



My original observing position became completely pointless as trees grew (and grew) around our garden. Ironically the view is clear all round in the drive just beyond the gate. But our neighbours are all afraid of the dark and need multiple bright lights on all night or they cannot sleep.

Somehow I had loosened the drive worm housings so the control paddle had no effect. The worm housings were moving around the wormwheels instead of the wormwheels being driven. I couldn't see this at first despite the bright moonlight. A 13mm spanner to the hex headed screw holding the housings soon solved that problem. The mounting then responded to the paddle controls.  

Full moon TZ7, 20mm no-name Plossl, 6" F:8 refractor. 
PhotoFiltre improved! Gamma reduction and contrast increase.

I was concentrating on Jupiter. Meanwhile everything was dripping wet with dew. Once, when I glanced through the telescope without the eyepiece and the objective was completely misted over! I broke with convention and mopped the front face with a clean handkerchief. 

I have a long, tubular, foam, slip-over dewshield extension but it was hiding somewhere in the shed. It is nothing fancy. Just a roll of black camping mattress and a rubber band. It works amazingly well compared with the stumpy, original, metal dewshield which came with the Celestron CR150HD.

 Jupiter proved far more difficult to capture. No visible markings even in the "best" of my hand-held, afocal snaps. I literally held the camera up to the eyepiece and snapped away every time I could see a bright blob on the camera screen. Two belts were clearly visible visually but I completely failed to capture them. I also lost a moon while reducing gamma in PhotoFiltre!  This is a heavily cropped shot with considerable gamma reduction to kill flare. Had I the patience I could have gone through the endless TZ7 menus and found spot metering. But I didn't. I had slightly more success with older digital cameras when photographing the planets in this crude way in the past.

 What I really need is a sleeve on the focussing mount to give the camera lens something to locate into. This would ensure centring on the eyepiece and also help with squaring-on.

I am always afraid to use a simple camera clamp to the focussing mount. Because the zoom lens might strike the eyepiece under power on camera switch-on. The lens seems to automatically extend for about an inch (25mm) each time the camera is switched on. This gives a fixed clamp no leeway to avoid direct camera lens to eyepiece contact.

These are my best images of Mars using simple hand-held, afocal methods.

A run through PhotoFiltre to enlarge, then adjust gamma and contrast has helped to bring out detail and reduce flare and false colour on the limb.

 Each image shows a different face of Mars.

A magnifying lens on the centre of the focussing screen would be useful for astronomy. I can't easily wear my reading glasses at the telescope just to enable me to monitor the camera screen. 

I don't own a laptop so can't try my webcam at the telescope. Without a camera clamp or lens, "nose socket" I can't take decent HD astro videos either.

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