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Last updated: 19 December 2008

4 June 2008

During a recent visit to Oracle Observatory I did some prime focus astrophotography on the ETX-125 using my Nikon D70 DSLR. I set the focus using the Stellar Technologies International Stiletto Focuser (a great focusing aid!) and took many images (all at ISO 1600) over the next 40 minutes. The first eleven were 30 second exposures each, and the last 20 were 15 seconds each. After I returned home, I used Lynkeos 2.2 on my Apple MacBook Pro to align, stack, and crop the best 6 images (mostly 15 second exposures) and here is the result:


I then photographed M57 at prime focus over the next hour. I took 22 images (ISO 1600), all but 2 were 15 second exposures. Here's the cropped, aligned, and stacked version of the best 12 images:


13 March 2008

I finally had a chance to stack the images of M42 I had taken through the ETX-90RA while at Oracle Observatory on 7 March. The image I had posted earlier (see 7 March below) is just a single, non-stacked image. But here is a stack of 10 images, each about 30 seconds duration at ISO 1600 with the Nikon D70 DSLR. Stacking was done in Lynkeos 2.0 running on my MacBook Pro with Mac OS X 10.5.2. The final image was also cropped. As you can see, more details are brought out by stacking the images, in this case for a total exposure duration of 5 minutes.


7 March 2008

I did some astrophotography through the ETX-90RA while at Oracle Observatory. First up was M42, the Great Nebula in Orion. I attached a wide-field adapter at prime focus and then added the OPT prime focus camera adapter to that. I then attached the Stiletto Focuser to focus the image. It had been awhile since I had first tried the Stiletto and then I had only tried it on the LXD75-8"SC (yes, the one that was stolen). I was pleased to discover that it worked fine on the ETX-90. I then swapped the Stiletto for the D70 DSLR. The image appeared in focus in the viewfinder so I started taking some photos. The best shots were 30 second exposures at ISO 1600. Longer exposures were trailed as I was just letting the ETX Right Ascension motor do the tracking with the telescope on a Equatorial Mount and only roughly polar aligned. After I completed a series of photographs of M42 I then moved the telescope to M45, the Pleiades. I used the same set up for a series of exposures with 30 seconds being the best. At this short duration there is no nebulosity visible however. But the familiar star pattern is clearly visible. Here are the two best photos, M42 on the top and M45 on the bottom. Some Raw image adjustments were made in Apple Aperture 2./p>



12 June 2005

M31 guided piggyback photograph taken from Oracle Observatory with my new Nikon D70 DSLR mounted on my ETX-90RA. Details on this and other M31 piggyback astrophotographs taken on this trip are discussed on my Nikon D70 DSLR astrophotography page.


Go to the 2002-2003 Deepsky Astrophotography page.

Go to the earlier Deepsky Astrophotography page.

Go back to my ETX Home Page.

Copyright ©2005, 2008 Michael L. Weasner /