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views from an etx 105 uhtc

Started by cysmarc, 10/11/2005 07:03AM
Posted 10/11/2005 07:03AM Opening Post
Hi,
I've seen claims of seeing the cassini division through an etx 90 using the 26mm plossl. I can barely make it out using a 7 mm u.o. ortho in my 105 (210x). I live in a light polluted area and I know the angle of the rings ain't that great. Are the claims about the etx 90 outragious, or is there something wrong with my optics?
Posted 10/14/2005 04:58AM #1
>>Hi,
I've seen claims of seeing the cassini division through an etx 90 using the 26mm plossl. I can barely make it out using a 7 mm u.o. ortho in my 105 (210x). I live in a light polluted area and I know the angle of the rings ain't that great. Are the claims about the etx 90 outragious, or is there something wrong with my optics?
=======

First, I always take what others have done with a grain of salt, I enjoy what I can do and hope to get better. The fact that J. Reynold Freeman was able to view the entire Herschel 400 with a 55mm refractor says a lot about his skill and experience but in reality has nothing to do with me.

I owned an ETX-90 for a short while. While it might be possible to see the Cassini at 48X in an ETX-90, I never did. If someone actually did, it would probably be a combination of very good seeing, an experienced observer and a fair amount of imagination.

Rod Mollise, a very creditable and experienced observer was able to see the craterlets in Plato with an ST-80. To me this is more impressive than seeing the Cassini at 48x in an ETX-90 but I attribute it to Rod's experience and skill as an observer. While I would be thrilled some day to duplicate this, I know the reason I haven't is not because something is wrong with my scope or me.

It is just a remarkable observation and one to be admired.

In my book seeing the Cassini is more about seeing conditions than anything else. Aperture is a help as well. The fact that you can see it,

Waiting until Saturn is well above the horizon is important, trying to see finer details looking though that extra atmosphere and turbulence makes it more difficult to see.

Looking over houses, building, trees, warm asphalt, all common in an urban setting, cause local turbulence/heat waves that can seriously disturb the view and kill any planetary detail.

Light pollution should not affect your views of Saturn, light pollution is only a problem for DSOs.

Bottomline: Look at the bright side, you are seeing the Cassini division...

Jon