2" or 1.25" eyepieces?

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2" or 1.25" eyepieces?


Post by Rmdigby » Mon Aug 12, 2019 7:16 pm

My first telescope is a Celestron 127 with 1.25" receiver for eyepieces. My new Orion xt10G has 2" capacity. As I begin to purchase new accessories, should I go for the 2" stuff or drop down to the 1.25" with the adapter? The optics that came with the Orion appear to be a better grade than the Celestron.
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Re: 2" or 1.25" eyepieces?


Post by Ozman » Mon Aug 12, 2019 7:39 pm

To fully utilize the wider field the Dob offers, you will need 1 or 2 low power wide field 2" EPs. My most used is the ES 18mm 82 and for a wider field the ES 24mm 82.
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Re: 2" or 1.25" eyepieces?


Post by Bigzmey » Mon Aug 12, 2019 7:43 pm

The quality of EP is not determined by EP diameter. The only reason to have 2" EP is to get wider field of view. So, typically one would have one or two 2" EPs for the low power wide field views and the rest would be 1.25" EPs.
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Re: 2" or 1.25" eyepieces?


Post by mcolbert » Mon Aug 12, 2019 9:08 pm

just on reflection, having read many similar threads over the years, along with innumerable conversations about EPs in general etc, I would say to be prepared to collect and use EPs of different sizes. This may happen as you buy further OTAs, so buy what is required for the time and instrument ... and your astronomical interests of course. I have 0.965s, 1.25s and can see the possibility of purchasing 2 inchers as well, as my desires / needs alter. Now, that being said, remember too that people have individual responses to EPs. Then, there are filters. ;)
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Re: 2" or 1.25" eyepieces?


Post by JayTee » Mon Aug 12, 2019 10:10 pm

And don't forget, that when treated carefully, an EP can last for a very long time. I have and still use EPs I bought in the 1970s!! This is the argument I use for don't go cheap (if you can afford something better), because that high quality, expensive EP could realistically last you 50 years!

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Re: 2" or 1.25" eyepieces?


Post by Star Dad » Tue Aug 13, 2019 6:23 pm

I have 40,29.5and 9mm , 2x Barlow 2" - Can't find many, if any, higher EP than 9mm
I also have 3,4.7mm, and 5x barlow 1.25".
Don't use any of the 1.25s much - except maybe on the moon. Has to be a spectacular night for the 3 to be of any use. Don't know what I was thinking when I bought the 5x. Maybe AP???? I'll have to try it out on Jupiter next chance I get.
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