It is ower... yesterday, after a nice, sunny day, clouds came with the dusk and obscured the sky. I hoped to use our new, still unfinished, observing shelter for the fist time. A better occasion to dedicate it to observing can not be imagined! Old equatorial mount was mounted on the central pier just minutes before, and I wanted to align it on the Polaris, but clouds did not permit it. So, I had to align by memory, and to go to bed, hopping for the best.
Our new shelter is built on the top of a small shed to save some ground area, and to be above ground air currents. The shelter is still mostly unfinished, thus the "walls" of plastic foils, but it is fully functional and fun to use. The observing area is about 2,8x2,5 m (9x8 ft) large, with an telescope pier in the middle. The roof is made in two sections which can move in opposite directions.
We wake up at dawn. The morning was perfect, clear blue sky and cold air. While the Sun marched out of the horizon mist, I prepared the instrumentation for the event of the century. Messier (a 65mm F/8 refractor used at 28x) was there as visual instrument. A 200 mm telephoto lens was mounted above it with QC 4000 pro webcam was coupled to it. This combination suits well the full-disk Sun and Moon photography as the disk fits nicely to the chip area of the webcam. To improve sharpness and reduce problems with focusing, the stop was set to F/8. A piece of Baader visual solar foil is used as a filter. Another piece of the same foil served as filter for the Messier telescope.This german made mylar foil is common in Europe and is of very good quality. A small finder by side of the telephoto lens was modified for the occasion: its aperture was limited to ca 5 mm (1/5") by a cardboard stop, and instead of an eyepiece a hollow ring with a paper cover was used to make the Sun image visible. Such "solar" finder proved to be fun to use! Actually, it would function equally well even without the objective lens, but as this small finder was already there I did not bother to make a new solar finder...
Doroteja is checking the situation on the visual scope.
Visually, the sight was impresive: a pitch-black sphere (I know, I know, it should be circle, but I had a very strong impression of plasticity of this ball in front of the solar disc). At moments of steady seeing I sometimes saw a bright spot in the midlle of it, but I suppose it is a visual effect only. The picture on the laptop screen was equally impressive. At few ocassions we put the webcam on the visual scope to get a larger image. One such ocassion is illustrated on the picture below:
"Real time" imaging. The picture on the laptop screen serves to check the progres and quality of smal avi films that we make at regular intervals....
At the end, some 50 avi-s are waiting to be post-processed at home computer. Here are the first results:
Venus in front of the solar disc, imaged through the 200 mm telephoto. The brihter solar limb, bright ring arround Venus and brighter center of the Venus disc are effects of webcam and image processing.
Webcam on the visual scope (focal lenght 500 mm) produces a larger image, but the whole solar disc can not fit onto the webcam chip. This picture was taken a few moments before the 3rd contact. The 3rd and 4th contacts were obscured by a few small clouds that were on the wrong place on the wrong moment. So is observing, the total cloud coverage was maybe 1 or 2%, but the clouds were directly in front of the Sun!
But, after all, we had more that 4 hours of totally clear sky and a lot of joy in observing this rare event!
After a fey days long torture of our old PC with Registax, all avi films taken with the webcam were transformed into still images. We then took one by one, cut out the central part of them so the Sun is precisely in in the middle of the image. As we swiched camera between two scopes, we also had to rotate those taken after a swich of them to get them into the same orientation as the first ones. At the end, we used a small freeware program, JPGvideo, to produce a small movie of the transit, but at 1800x of original speed. The result is here, but beware, it is almoust 1 MB in size! Click with the right button and download!