7" f/12 R35 iStar refractor: Alignment, stepladders and Sun spotting.

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Once I had removed the slop from the focuser backplate it was easy to align the Cheshire on the center of the objective. The objective itself proved to be well aligned with the focuser.

Having mounted the OTA on the MkIV and fitted the full aperture solar filter I could see a single, large sunspot near the limb and suggestion of faculae in the area surrounding it. The umbra and penumbra were well seen on the sunspot.  I then stopped down the aperture to 6" and was rewarded with a sharper view. A 4" stop proved too small and actually seemed to soften the sunspot.

Trying to capture any of this with afocal 'snaps' is, again, proving frustratingly difficult. The image is so bright and uniform that the camera seeks out dust and dirt on the eyepiece in the absence of anything else on which to focus. I shall persevere in the hope of finding a setting which captures the visible details in time for the Mercury transit. My very first, Sony, compact digital camera took flawless astro images with auto settings. When that stopped working I bought this little Canon Ixus117 precisely for its short zoom and modest aperture as being most suitable for afocal, astro photography.

As can be seen in the image my new, folding, builder's stepladders have arrived. They were heavily discounted via an online dealer here in Denmark which finally swayed me to invest. I have been promising myself a pair of these steps for literally years after seeing a pair in a builder's merchants. These steps make perfect sense in providing incredible stability and modest height without having to teeter on narrow and uncomfortable, ladder rungs. Nor does the usual stepladder frame get in the way when loading telescopes.

I noticed instantly that I was standing on proper treads with decent width and depth which helps greatly with hands-free balance. The step's relatively gentle slopes are ideal for climbing with a large and heavy OTA in one's arms. The sheer size of these steps provides a large and steady footprint with a generous top platform about a 94cm or 29" high. This height provides me with the ability to look down on top of the horizontal OTA and MkIV mounting to make adjustments, tighten the clamping rings and fit a solar filter or aperture stop. 

My first half decent image of the Sun by afocal photography with the 7" stopped down to 6".[f14.4 =f/19.4 R35 equivalent.] Slight zooming seemed to help the camera find the correct focus. Remember that this image was obtained simply by holding the compact camera up to the eyepiece with a plastic, detergent bottle top, collar/adapter to center the Ixus 117 camera lens [nose] on the eyepiece without its rubber eye-shield fitted. [26mm Meade 4000.] I quite pleased with this image after struggling to capture anything at all! The camera registered 1/250 @ f/5.6. Image downsized from 3000x3000 pixels to 1000x1000 in PhotoFiltre with slightly increased contrast, reduced gamma but no sharpening. The Sun was at 48 degrees altitude above the roof of the house.

Indoor stepladders have proved lethal out of doors and I have toppled several times over the years! Finally, I have access, stability and safety to reach my telescopes on their tall pier without compromise. The steps will also be ideal for reaching the eyepiece of my 10" f/8 should I ever finish it. Now I have a further incentive to do so without worrying about ladder safety in the dark.

This type of low stepladder is used by the owners of some very expensive APO telescopes on an astro forum I frequent. If they are good enough for mounting telescopes costing many tens of thousands then they are probably good enough for little old me and my more modest, optical creations.The stepladder may even prove useful as variable height seat for refractor observation with a simple cushion for extra comfort.

I left the telescope drive running all day and was amused to see it pointing down at the ground in the west after dinner as it followed the sun well below the horizon. I went out again at 10pm to have a look at Jupiter. Seeing was softer than  ever in the arm and windy conditions. I tried various powers but only the lowest I tried 110x showed much detail in the belts. It wasn't a case of occasional sharpness but of regular loss of all detail. Yet again a tiny moon exited the limb and put distance between itself and the planet.

Towards the end I had a look around with the 32mm and 26mm eyepieces. The sky is never really dark at 55N at this time of year until well after 11pm. Even as I finished tidying up at nearly 11.30pm the dimmer stars were only beginning to show themselves. I am becoming quite at ease with the large instrument now. Even bringing the 'nose' down to remove the solar filter and refit the plywood storage plug. Having the instrument raised and leveled on the trailer jockey wheels gives it the extra height I need for sitting comfortable at the eyepiece when observing Jupiter at around 40 degrees. The new steps were handy for loosening the upper ring's clamping screw and tightening the clutches on the wormwheels before bringing down the OTA. Tipping it up slightly and allowing it to slide through the open rings is a comfortable way of handling the long and heavy tube.

Click on any image for an enlargement. 

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