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Old 13-05-2021, 06:38 PM
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thegreat1 (Gautam)
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Join Date: Feb 2021
Location: Quakers Hill, NSW
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Originally Posted by mura_gadi View Post

Keep in mind that you are unlikely to find one line that suits all your viewing needs. You can have some real pearls and clangers in the same line up.

Factor in exit pupil on your selections, at f8 - 12mm/18/24mm will give you 1.5mm/2+/3mm exit pupils, somewhere between 2-4mm is said to be optimal for comfort.

Eye relief, you have the two plossl's, there is a mile of difference in the eye relief they provide. If you find the 10mm a little harder to use, you may want to think about ep with good eye relief - (15mm-20mm). (A $19 plossl will tell you a lot about what eye relief you are looking for.)
Hi Steve,

Thanks for sharing your knowledge and the link. Much appreciated.

I've read a bit about exit pupils and it's fascinating to understand it's practical application from a light gathering point of view.

From your experience, is there any merit in looking for a 2 inch eye piece for wide views - a low powered one maybe - instead of a 1.25inch wide view ep?

Originally Posted by Don Pensack View Post
I calculate a 1200mm focal length?

That would be eyepieces like the Saxon Cielo HD, though it is of note that these eyepieces are identical to the Celestron X-Cel LX, so you might find them for less if you shop a sale.
Or the BST Starguider ED or Astrotech Paradigm eyepieces. You could get these from a US company and even with shipping pay less than typical AU prices.

I'd skip acquiring more Plössl eyepieces because the eye reliefs get uncomfortable at focal lengths under 14-15mm focal length and because I think you'd find the wider fields more engaging.
Like the SkyWatcher Wide Angle 66° eyepieces (6, 9, 15, 20mm), also sold under the Orion and Sirius brand names in Oz.
or the Skywatcher 58° Long eye relief eyepieces (these are not Plössls, by the way)
Hi Don,

Thanks for sharing your insight.

You are correct. The focal length on my scope is 1200mm. Sorry, a newbie mistake for not quoting it. Will fix it.

A wide 60 degree and above field of view on the 1.25" focuser does sound exciting. I will look up the Saxon ones along with the Skywatcher ones you've mentioned.

Another question, would getting a 2 inch ep with a wide field of view offer significantly better viewing experience?

I agree to your point regarding the lack of comfort on a high powered Plössl such as my stock 10mm. Between my 25mm and 10mm, the 25mm is used more.

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