On the 31st August 2009, we had a reasonably high and bright ISS pass, as the space station passed at about 60° altitude and reaching -2.8 apparent magnitude.
Unfortunately the Space Shuttle Discovery (STS-128) was still on its way to the ISS and had not yet docked. The Space Shuttle actually passed overhead about 8 minutes before the ISS, but they happened very early in the evening and the sky was still blue so I couldn’t spot the shuttle pass.
8 minutes later, the sky was dark enough and the ISS bright enough for me to be able to spot the pass. It came from the SW through to the NE passing through NW, which means trees in my backyard. So I couldn’t get it in my finderscope until it had passed its maximum altitude.
Continue reading for more information about capture and processing.
The first two images were taken through the branches, which is why they’re not as bright as they should be. The third image reflects the quality of the remaining frames I captured – just not sharp enough. I had the shutter speed at 1/1250s exposure, but combined with the seeing, it seems it just wasn’t short enough to capture fine detail.
The other settings were gain at 903, gamma at 125 and capturing at 60fps using my 12″ Newt on a dob base, with the DMK21AU04 and a 2x barlow. I captured a reasonable number of frames with the ISS on them, but they just weren’t very good quality.
My dob base is showing bad signs of wear now, probably from exposure to the elements with the particle board base. The teflon pads on the bottom of the top section have started gouging large holes in the base plate, meaning I couldn’t move the dob smoothly in azumith motion any more. Luckily I found a lazy susan that we had a TV sitting on, much smaller than the top section but just large enough for the top part of the base to sit on.
Now I have very smooth motion in azumith, just a little bit wobbly because the lazy susan is not quite large enough in diameter. But it works!
Anyway I’m not happy with these images, but it got me outside again and looking forward to some more ISS passes in a few days time. Hopefully the shuttle will still be attached!
Thanks for looking.