Lense Help please... (Cont... Part - 2)

akadus · Guest

Dear Stan,

First of all, thanks a lot for your help - it was much appreciated. However I have been looking up this eyepiece stuff and have a few more questions for you.....

1. How would one compare a Super Plossl eyepiece with Super Wide Angle or a Ultra Wide Angle eyepiece of the same focal length say 6mm? (also something about the 4000 series?) Specially since thay all are so expensive!!

2. I am also thinking of getting a #126 2x Barlow Lens, would that be fine for my ETX-90??

3. What would be a good sellection of filters? (also to view the sun, moon, etc.???)

4. And finally, would or could all the above make a difference specially when viewing conditions are not ideal?? For exmple, there is a lot of air pollution in New Delhi...

Once again, thanks for your help.
Best Regards,
AK
akadus@yahoo.com

Stan @ Opticsplanet · Joined: 12 Jan 2004 Posts: 98 Location: Chicago, Illinois

There are many different designs of eyepieces. They include; Plossl, Super Plossl (2 most common), Ortho, Nagler, etc. Plossl's are the most common, and the best overall quality for a decent price. They have a decent field of view, which makes them work well for planets or deep space objects. Wide field eyepieces are generally found in a low power eyepiece, 25mm or larger. Low power, wide field, are recommended for deep space viewing. High power eyepieces are more for planetary viewing. A barlow lens is a way to double the magnification of an existing eyepiece. A 26mm will become a 13mm and so on. You will still have the better eye relief from the low power eyepiece.

Unfortunately, we do not carry any filters here. A moon filter only really reduces the brightness of the moon, and can in some conditions, improve detail. Most solar filters will allow you to see not much more than sun spots, no flares. Other color filters will increase detail on different planets.

If you are in a city or suburb enviroment with a lot of lights, if will be tough to see any more than the moon and maybe some planets. Even then you can still get some detail on those objects. If you want to see anything more than that, you would need to find a more secluded dark viewing site.

I hope this has been useful. Thank you.
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Best Regards,
Stan Mack
http://www.OpticsPlanet.com
Phone: (888) 263-0356
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