Author Topic: Looking for a new Wide-Angle EP  (Read 80 times)

rennlispuring

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Looking for a new Wide-Angle EP
« on: December 29, 2017, 05:49:11 PM »
I recently went to a 2 inch diagonal on my Nexstar 8se and bought a 2 inch SuperView 42mm EP from Highpoint Scientific for my wide-angle EP. It's okay but it's a little hard to focus and the stars at the edge of the FOV seem to be pretty distorted. I use it as my go to EP for DSOs.

I'm thinking of upgrading it and had my eye on a few Explore Scientific EPs. The 62 degree line is on sale right now and the 40mm would give me just under the FOV that I have now. I also had an eye on the ES 68 degree 40mm and the 82 degree 30mm but those jump up in price pretty substantially. Will I really notice a huge difference with those over the 62 degree line?

Any recommendations would be appreciated!



nasapehe

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Re: Looking for a new Wide-Angle EP
« Reply #1 on: January 01, 2018, 12:33:28 AM »
Check these out too. I got them when they were clearing them on the ES website.https://explorescien...0-25mm-eyepiece

But on brighter objects you might notice halo or diffraction striae. Hit miss. Of the two I had, one was good. For the price, great!
EDIT: corrected link. p.s. they're most likely the same as GSO types which might cost a little less.

cesconali

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Re: Looking for a new Wide-Angle EP
« Reply #2 on: January 03, 2018, 12:41:04 PM »
The ES 35mm 70° is a great value for the SCT. If it were a faster scope then the more pricey ES 30mm 82° would be a better choice.

freddormasa

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Re: Looking for a new Wide-Angle EP
« Reply #3 on: January 10, 2018, 11:32:27 AM »
Quote
I also had an eye on the ES 68 degree 40mm and the 82 degree 30mm but those jump up in price pretty substantially. Will I really notice a huge difference with those over the 62 degree line?
Yes! At least the 30mm is a VERY substantial leap in apparent field over a 62° eyepiece.

I used to own a C8 and often used a 30mm ES82 in it. It is a fantastic combination for most Messiers and bright NGC objects. The stars are a little comatic along the edge but this is inherent in the SCT design and you can't escape it, unless you buy a Celestron Edge SCT or one of the Meade ACFs.Clear skies!
Thomas, Denmark

soamezquipack

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Re: Looking for a new Wide-Angle EP
« Reply #4 on: January 11, 2018, 04:00:27 PM »
Quote
The ES 35mm 70° is a great value for the SCT. If it were a faster scope then the more pricey ES 30mm 82° would be a better choice.


Thanks, I assume you're referring to this one?

https://explorescien...0-30mm-eyepiece

I didn't see any other ES branded 70 degree EPs.

sremburjuni

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Re: Looking for a new Wide-Angle EP
« Reply #5 on: January 12, 2018, 07:36:35 AM »
I've been using 82-degree eyepieces for so long now that 62-degrees is almost like looking down a tunnel to me. Jumping up to 72-degrees (TV Delos) is wide enough to be comfortable and I can live with that. Jumping up another step to 78-degrees (Baader Morpheus) is very immersive, extremely natural feeling and the nearly 20mm of eye relief is very comfortable. Jumping up once again to 82-degrees (TV Nagler, ES 82) is very nice and, even though these don't typically have long eye relief, for the most part, they feel comfortable and natural. 82-degrees is the most my eyes can see at one time without turning my head from side to side or up and down.

Note: There is a new wide field lineup available from Orion, the LHD 80 Lanthanum series. As of about a week ago, I still couldn't find any good field reports or reviews for these eyepieces. What makes them different is the 20mm of eye relief and that can be significantly reduced if the eye lens is sunk down into the housing (example: ES 30mm 82).

In actual use, when changing between eyepieces, going from 72-degree eyepieces to 76-degree eyepieces is a significantly noticeable improvement while going from 76-degree eyepieces to 82-degree eyepieces feels so similar as to be hardly noticeable at all. Both the 76 and 82-degree eyepieces have a wonderful "porthole-into-space" feel to them. All I can say, is I've tried entirely too many inexpensive eyepieces over the years, always searching for that cheap magic bullet that simply doesn't exist. So consider spending more, buying once, and getting build-quality and performance (mostly edge sharpness and increased contrast) that will last for many years. You won't regret it.

Anton Balderrama

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Re: Looking for a new Wide-Angle EP
« Reply #6 on: January 14, 2018, 01:14:15 AM »
Thank you everyone! As luck would have it, an ES 30mm 82 degree popped up in the classifieds about an hour after I submitted this. I jumped on it. I'll lose a tiny bit of AFoV from what I'm using now but I imagine the quality of the view will be much better.

Matt Marquez

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Re: Looking for a new Wide-Angle EP
« Reply #7 on: January 15, 2018, 09:55:58 PM »
Quote
Quote

The ES 35mm 70° is a great value for the SCT. If it were a faster scope then the more pricey ES 30mm 82° would be a better choice.


Thanks, I assume you're referring to this one?

https://explorescien...0-30mm-eyepiece

I didn't see any other ES branded 70 degree EPs.
35mm 70 AFOV for $99 seems like a good price if you only want to get one and have good exit pupil.
30mm 82 AFOV will be a keeper and maximum TFOV for 30mm eyepiece with good exit pupil.
40mm 68 AFOV comes close to maximum TFOV avalable with 2" eyepiece (UO Koenig MK-70 40mm 70AFOV or TV 41mm 68 AFOV Panoptic are slightly wider).

John Abreu

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Re: Looking for a new Wide-Angle EP
« Reply #8 on: January 16, 2018, 04:53:10 AM »
Quote
Thank you everyone! As luck would have it, an ES 30mm 82 degree popped up in the classifieds about an hour after I submitted this. I jumped on it. I'll lose a tiny bit of AFoV from what I'm using now but I imagine the quality of the view will be much better.

I don't think you'll lose any FOV but should gain a little as the Field stop of the 42mm GSO is 41.5mm and the ES 30mm 82° is 43mm
You can compare and let us know.

mosretouless

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Re: Looking for a new Wide-Angle EP
« Reply #9 on: January 17, 2018, 12:59:11 AM »
Quote
Quote

Thank you everyone! As luck would have it, an ES 30mm 82 degree popped up in the classifieds about an hour after I submitted this. I jumped on it. I'll lose a tiny bit of AFoV from what I'm using now but I imagine the quality of the view will be much better.

I don't think you'll lose any FOV but should gain a little as the Field stop of the 42mm GSO is 41.5mm and the ES 30mm 82° is 43mm
You can compare and let us know.
Interesting, I was just plugging the advertised specs of the eyepieces into this calculator to get the Apparent Total FOV.

https://astronomy.to...ew_calculations

I'll compare once I get the new EP in.

Marvin Neboet

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Re: Looking for a new Wide-Angle EP
« Reply #10 on: January 23, 2018, 07:33:02 AM »
AFOV of the eyepiece divided by magnification will give you FOV. Fairly simple.

specconcheckre

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Re: Looking for a new Wide-Angle EP
« Reply #11 on: January 25, 2018, 12:14:49 PM »
Quote
AFOV of the eyepiece divided by magnification will give you FOV. Fairly simple.

I always use the eyepiece Field Stop divided by the telescope Focal Length X 57.3 as I find it more accurate.
Either is acceptable however.

loraderclot

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Re: Looking for a new Wide-Angle EP
« Reply #12 on: January 25, 2018, 05:35:10 PM »
Quote
Quote

AFOV of the eyepiece divided by magnification will give you FOV. Fairly simple.

I always use the eyepiece Field Stop divided by the telescope Focal Length X 57.3 as I find it more accurate.
Either is acceptable however.

In the case of the 42 mm GSO Superview the error in using TFoV=AFoV/mag is significant, about 15%. The field stop calculation is the one to use if you want to compare eyepieces..

Jon

ceisilipan

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Re: Looking for a new Wide-Angle EP
« Reply #13 on: January 25, 2018, 07:24:34 PM »
Good choice, the bresser 70s will not be any better on the edge than the superview.  The es82 will be sharp to the edge. The coma in an SCT is not as terrible as they say, unless you are trying to image with a large chip.

Danny Rodriguez

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Re: Looking for a new Wide-Angle EP
« Reply #14 on: January 26, 2018, 01:44:09 AM »
Very informative thread. I really look forward to following this. You guys always provide awesome advice and information.
So thank you all for taking the time to provide your feedback.