Tuesday, June 05, 2012

afternoon astronomy (Blue Mountains)

Between chores, I did a little bit of solar observing. And helped out people with their equipment.

Assisted Dietmar with hydrogen-alpha set-up on Tele Vue 101 refractor. He couldn't seem to find the 1¼" mirror diagonal. I pointed to my old Celestron on the shelf. I gather he had been visually expecting something else, an older or different unit. He popped it in. It was a very good view!

Photo by Lora Chow.

I moved the Oberwerk battleship binoculars and big wooden tripod outside. I set up my custom baader film solar filter over the 100mm objectives. And took in the Sun. A great view! I was pleased to see some sunspots. That meant we'd get a more interesting view when Venus would show up...

The filter wasn't quite done. I had prepared some warning and information labels. And I wanted to add a Sun-finder. But there didn't seem to be enough time.

Tried to use the tripod with the Manfrotto quick-release. But it didn't seem to work right... Even when I had the tensioner at maximum, it would not hold steady, under the weight of a PST or binoculars. I put it aside.

Dietmar's account on the Paramount control laptop kept logging out! I changed his Windows Control Panel settings (or thought I did) to go into "never off" mode.

I tried to help Manuel with centering his SCT on the Sun, and then focusing. It is curious. Something about this, some aspect of this, seems to escape him. Is it because he is not a visual learner? Maybe things like pointing, alignment, collimation, etc. are difficult for him. There are elements of math. To me, I can "see" paths, light rays, so it is straight-forward or easy for me to grasp.

He was also surprised at how little of the Sun he could see. Despite a focal reducer. I said it was due in part to using a long focal length SCT. Very long. And the design of the camera and chip.

On top of this, the Sun was drifting. Amplified with his long focal length and narrow field camera. I explained that it was to be expected. He'd be off a bit in the daytime because he couldn't do a polar alignment. While the GBO pointed north, he'd be lucky to get it. I asked if the mount supported a daytime alignment. I knew the RASC's NexStar 11 GPS supported a "Quick Align" mode that could even be refined. Manuel didn't know. So, I showed him how to dial out the drift, in azimuth, and left him to it. (I realised later, I had assumed he had checked the altitude latitude angle.) Later, he gave up in frustration.

Around 4:30 PM, Manuel G offered his camera for imaging the Sun instead of the MallinCam. Particularly since he wasn't going to image with his 'scope. He said his camera would produce a better image. But I was a little anxious about a late-in-the-game change. Logistically, of course, it would be more than just a camera swap. In addition, we'd have to worry about cabling and software. It'd be easiest to use and record on his computer. And then there'd be file formats, file size, transfer issues... When I was pulled away by another member.

I heard later that Jim said Manuel G's 'scope was out of collimation. Really? Again?! Manny was upset. He gave up using his 'scope. Asked to use Manuel S' SCT for imaging. They switched...

Later I saw his camera rigged up to Manuel S's new(ish) Celestron 'scope. Out on the Observing Pad. Which, curiously, was not far from Jim. I wondered if this was serendipitous. Manny would be probably better off beside an accomplished imager.

Still, he snagged me. I briefly helped Manuel G with centring and focusing on the Pad.

We loaned the 55mm Plössl to Manual S for viewing. It let him see the whole solar disc.

I asked Phil to get out the Coronado Calcium-K 'scope for Sharmin. He grumbled about it but then dug out the two PSTs and the motorised mount while I fetched The Black Cloak of Doom. When he protested again, I took a look. The angle of the main support plate was all wrong. While polar aligned, we couldn't adjust the slow-motion controls enough. This clearly illustrated just how awkward the mount is. We need something other than this slow-motion adjusters with greater ranges of movement. Ball-heads perhaps? We finally moved the K-line to a regular tripod.

Manuel G reported finding a setting in the user guide about tracking at the solar rate. Celestron disabled the option to go to the Sun, wisely so, and by extension, did not allow tracking at the matching rate. He was very happy with this discovery. Holy cow: he read the book!

At some point, I showed Manuel S the ADDS web site. Encouraged him to use it to predict weather.

While preparing dinner, I set up the MallinCam. Unfortunately, it was too last-minute, we were all too busy, so I had to forgo tutoring Phil. I put the monitor on composite feed; sent the S-video to the computer. And suddenly I realised, in packing fast and light, I had forgotten my USB kit! We did not have a serial-USB adapter... Oh oh. That meant manual camera control. Yikes. Fortunately, we'd be staying on one subject... Millie helped me focus.

More people had arrived: Stu, Doug, Kiron (and 2 guests), Daniel (who knew me) and guest, Tom and Sharmin, Jim C (as noted earlier). We were ready for the once (or maybe twice) in a lifetime event...

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