Niels Noordhoek's weblog » ETX90 http://www.njnoordhoek.com Fri, 02 Nov 2012 07:20:05 +0000 en-US hourly 1 http://wordpress.org/?v=3.4.2 There’s a little black spot on the sun today… http://www.njnoordhoek.com/?p=141 http://www.njnoordhoek.com/?p=141#comments Mon, 30 Apr 2007 13:50:28 +0000 admin http://www.njnoordhoek.com/?p=141 Using a solar filter that attenuates the suns light about 100,000 times, it is possible to safely watch the sun directly through a telescope.stack-sun-2x-iso1000-wavelet-crop.jpg

]]> http://www.njnoordhoek.com/?feed=rss2&p=141 0 Perfect seeing, perfect telescope http://www.njnoordhoek.com/?p=116 http://www.njnoordhoek.com/?p=116#comments Tue, 03 Apr 2007 21:01:19 +0000 admin http://www.njnoordhoek.com/?p=116 In an ideal world, a 512 pixel wide Saturn image would look like this:

saturn.jpg

But if an 8 inch telescope (like C8) would be used in perfect seeing, the resolution would be limited to (simulated with Aberrator):
saturn_aberrator_c8.jpg

For the 90 mm ETX90 it would look like:

saturn-etx90.jpg

]]> http://www.njnoordhoek.com/?feed=rss2&p=116 0 Best Jupiter+red spot so far http://www.njnoordhoek.com/?p=21 http://www.njnoordhoek.com/?p=21#comments Wed, 07 Jun 2006 21:29:00 +0000 admin http://www.njnoordhoek.com/?p=21 jg3-usm-levels.jpg

June 7th 2006, Jupiter, red spot and a hint of “red spot junior” in the lower right of “senior”.

Timelapse (animated gif) between 22h50 and 23h11:
jupiter.gif

]]> http://www.njnoordhoek.com/?feed=rss2&p=21 0 Lunar mosaic http://www.njnoordhoek.com/?p=51 http://www.njnoordhoek.com/?p=51#comments Tue, 04 Apr 2006 22:17:17 +0000 admin http://www.njnoordhoek.com/?p=51 2006_04_04_maan-etx90-usm.jpgMosaic of 15 registered and stacked (Registax 3) movies, made with ETX90 and Philips Toucam.

]]> http://www.njnoordhoek.com/?feed=rss2&p=51 0