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View Full Version : Astrophoto: The Bubble Nebula (NGC 7635) by Karel Teuwen



Fraser
2006-Aug-09, 03:34 PM
Every clear evening, as twilight dissolves into night, untold thousands of telescopes scattered across the globe turn toward the great beyond that lies above. But, increasingly, a camera is replacing the eyepiece as the favorite way to study the heavens. Taking deep space pictures was once the purview of a small, dedicated group of amateur astronomers. The technology available was daunting, expensive and time consuming. Luck was an important factor in producing an image that resembled its subject. But all that has changed in the past few years- producing deep space images, such as the one seen here, while still not a point-and-click exercise, has become much easier.

Read the full blog entry (http://www.universetoday.com/2006/08/09/astrophoto-the-bubble-nebula-ngc-7635-by-karel-teuwen/)

selden
2006-Aug-09, 06:46 PM
It seems to me that the premise

But all that has changed in the past few years- producing deep space images, such as the one seen here, while still not a point-and-click exercise, has become much easier. is contradicted by the final statement in the article:

Belgium astronomer Karel Teuwen produced this picture at his private observatory located near the town of Turnhout using a 16 inch telescope and an 11 mega-pixel astronomical camera. The total length of the exposure exceeded 12.5 hours.

If he had used a 6" reflector and a webcam for a few minutes, then I'd agree. :-)

jgabany
2006-Aug-10, 07:48 AM
Hi Selden!

Thank you for making this comment! Your point is well taken but seems to focus on the equipment and exposure time used to produce the photograph in this article. I understand your perspective but it may miss the point of what was written: images such as the Bubble Nebula would not have been possible by an amateur, not by any stretch of the imagination, without the recent digital revolution that has occurred with cameras and telescopes. The leap in affordable technology that inspires some to take very long exposures also inspires many, many others to produce pictures of much less challenging subjects, too!

For example, I recall setting by my Meade DS-16 telescope during 1986 to image Halley's Comet. I used the latest technology of the time- an off-axis guider, a OM-1 reflex camera, a power converter to smooth out fluctuations that caused the scope to track too slow or too fast and a bunch of other stuff that was recommended by the experts.

I stared into the off axis guider for hours making small manual corrections to the RA and Dec drive motors as I attempted to keep the dim guide star within a pair of illuminated cross hairs. It was cramped, cold, difficult and boring- quite frankly. I did not know if I succeeded until the next afternoon. Usually, I did not succeed. After many months of trying, I finally produced a decent picture, which by today's standards would not gather anyone's attention, then gave up the hobby for several years until technology could simplify taking pictures through a telescope.

So, I believe I am correct in saying that digital cameras and computerized telescopes have helped popularize astro-photography whether the amateur astronomer is using a 6 inch reflector and a web cam to image a planet or a 16 inch light bucket and an 11 mega-pixel camera to picture something towards the edge of forever.

foobird
2006-Aug-10, 02:20 PM
If only it was that simple. I have a 9.25 inch goto mounted on a plinth and polar aligned. My car satnav tells me where I am and my watch is synchronised with the web atomic clock. After alignment I consider it a success if the scope can find the moon! BTH I've read the manuals and all the forums for some years.

karel_teuwen
2006-Aug-10, 05:18 PM
Hi Jay and others,

This is my first post here on this forum and I'm glad R Jay pointed me at its existence. I hope to keep up-to-date and to learn a lot about my hobby here.
Now, I want to second the statement of Jay, that nowadays itís much easier to succeed as astro-photographer when you have the right equipment and the patients to use it. The hard part is the processing afterwards, there is so much to learn ! Just like Jay, I know what itís like to do some deep sky work without all those technology. I also did a lot of deep sky imaging in the late seventyís on film with a C8 and everything on manual ! In the best case, at winters, I could photograph 3 objects per night with 90 minutes of exposure time, with off axis guiding, like you Jay. It was hard work and there were many moments of great disappointments, but Iím happy I went true that chapter, so I have a lot to tell now. But just like Jay, and Iím much older now, I would never start again if things doesnít have been changed for the better.

Regards
Karel Teuwen