Text and pictures © 2007-2024 Guillaume Dargaud
Last updated on 2021/11/05
"The dinosaurs became extinct because they didn't have a space program." — Larry Niven.
My first attempt at using a telescope was thwarted by difficult conditions, to say the least. Although the seeing was the very best on the planet, the difficulty in setting up and using the equipment let to constant failure. I managed to get only one decent image in a year (shown here), which is not much by all means, and it wasn't even taken through the telescope ! I've recounted the story on this page.
Left: A 180° shot of the Milky Way across the Antarctic sky. Part of the telescope is visible on the upper left of the image and the band next to it is a faint aurora. The two white blurs are the Magellanic clouds. The dark area on the Milky way is called the Coal Sack and is a typical southern hemisphere feature, quite visible to the naked eye. The reddish lower part is light from the sun, still way bellow the horizon but shining nonetheless. More info about fisheye photography.
Right: Saturn getting ready to disappear behind the moon.
I own a Meade DSI Deep Sky Imager but I find its setup and use tedious, as well as the results subpar. But then again I'm no specialist and some people have managed to get excellent shots out of it. The problem is that its very reduced sensor size leads to very different results than what you see in the eyepiece. So lately I tried my new digital SLR mounted on the telescope.
Left: Saturn just a few seconds after emerging from behind the moon, an hour later. No image processing.
For the May 22nd 2007 conjunction between the moon and Saturn, I had the following equipment: a new Fujifilm Finepix S5 pro, still untested for night photography or long exposures, a beaten up Celestron Nexstar 5i, some accessories.
Right: A similar shot taken with a x2 Barlow.
I have a short writeup on the capabilities of the Fuji S5 pro for astrophotography as this camera has several advantages with respect to other SLRs.
Left: Deep sky image of M13. Only 30 seconds of exposure at 3200iso.
Note that on this kind of images, hot pixels may be a problem. Some cameras are better than others for astrophotography (what a surprise !), some of the desirable characteristics being that: it's a reflex mountable on a telescope directly (you need a T-ring), it has high sensitivity and low noise (usually meaning that the sensor pixels should be large), that you can optionally take darks and if possible remove them offline (with the manufacturer's software), you can disable the noise removal function, you can take RAWs for further post-processing, there's a mirror lockup function, there's a screen preview, the auto-exposure works on a T-ring (or even without lens)...
Right: That's Ago and me shooting at the moon.
Right: Plenty of stars above the spanish countryside.
Left: The sky above Riglos (following the stars).
At the end of october 2007, we took a week of vacation in Aragon, a region in north-central Spain. The sky conditions were excellent for astronomic observations: night temperature about 5~10°C, no humidity, only a few tiny villages to produce parasite lights, fairly high altitude (500 to 1000m). The main goal of the trip was to climb in Riglos, but since the days were short, I took my Celestron on the trip.
Left: Can you spot Andromeda in this wide angle view of the northern sky ? And the Milky Way ?
While we were at Riglos, the nights were always too windy. I tried to put the scope up, but apart from a few wide angle shots on a piggy mount, it was too shaky even for eye observation.
Right: OK, here's a better view of Andromeda, our sister galaxy, over a slew of stars.
Left: When I took the telescope, I actually had in mind the astronomic surprise of the year, comet 17P/Holmes, visible here as the large blue dot in the middle of Perseus and quite visible to the naked eye.
Finally when we left Riglos for Rodellar, the conditions were just perfect: no more wind, dark, clear, moon gone, mild temperature, good seeing, etc... I spent a night working on remembering how to do various things with the scope and fighting a few glitches and my own incompetence. Then the next day the scope started acting increasingly erratic. I changed the batteries and while I was rummaging through my stash of equipment I smelled a rat and turned around: the scope was on fire !!! I turned it off and then removed the batteries, but too late: all the electronics are deep fried... I have no idea what happened. C:-(
A week later I bring the whole dark mess to the lab. Electronicians are attracted from a distance by the smell: "Who fried a poor design ?". That's when I snatch them with: "I heard you're good. Can you fix that ?". Two hour later, they've rebuilt the power board and the scope is back online ! I can hardly believe it.