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Eyepiece help please - balancing?

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#1 mitaccio

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Posted 22 January 2013 - 05:41 PM

Edit: Anyone tried a 2" 100* Fov eyepiece with their 8SE. I want to know if you had any balancing issues. Any pictures to give me an idea of how big these eyepieces are?

Got the green light from the wife for a new eyepiece. Trying to choos between the ES 100*20mm and the ES82*24mm for my 8se. Who is using either of these and what do you like/think?

#2 hopskipson

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Posted 22 January 2013 - 09:38 PM

I have the 82*24mm and use it extensively. The stars are pin points on axis to about 85% of the field.

#3 Bob Griffiths

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Posted 23 January 2013 - 10:38 AM

You should NOT have any problem with balancing the eyepiece just may have to shove the OTA a little more forward on the dovetail..

I do not personally like even 82 degree eyepieces and limit myself to using 68-70 degree FOV ones, ..mostly Panoptics and Pentax XW's...which are not exactly light weight or small eyepieces..

Go for it

Bob G.

#4 mitaccio

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Posted 23 January 2013 - 10:50 AM

What is it with wider fov eyeieces that you don't like?

#5 Bob Griffiths

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Posted 23 January 2013 - 10:56 AM

What is it with wider fov eyeieces that you don't like?


I find them not at all comfortable to use... I have to shift my OLD worn out eyeballs all over the place to see the entire FOV ...I find this distracting and since I tend to spend most of my time observing on axis they just do not work for me personally..

BTW... I am not the only one who shares this opinion..

Bob G.

#6 Arctic_Eddie

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Posted 23 January 2013 - 11:29 AM

I agree with Bob. The eye can see a wide angle but the brain only sees some portion of the central area. Even my 68° EPs are pushing the limit. A simple test is to look down the street at a scene with a wide view. Now ask yourself just how much of that picture do you consider without moving your eyes. It's actually quite small. You can sense the presence of something in wide angle but the concentration is only about the central area.

#7 Peter9

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Posted 23 January 2013 - 12:35 PM

I use 70deg eyepieces for wide angle viewing. Even with these, I find I have to move my eyes to see the edge of the F.O.V. I can not see any advantage in using anything wider.

Regards. Peter.

#8 Midnight Dan

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Posted 23 January 2013 - 01:15 PM

I'm in the same boat. EPs with a 68 to 70 degree AFOV is plenty for me.

The wider EPs DO have some advantages. The first is that it takes longer for a target to drift across the field if you're not tracking. This is very handy when using a manual alt/az mount or a dob.

The other is more of an esthetic improvement. Even though you can't take in more than 68° at a time and have to "look around" to se the whole thing, the fact is that most people can see the edge of a 68° field way out there in their peripheral vision. With the wider EPs, that edge begins to fall away and you start to feel like you're out there with the stars, with no limit to your visibility. This is what people call an "immersive" view.

Personally, I find that to be a subtle advantage and not worth the extra cost. But clearly, there are many who are willing to pay the price for that feeling.

-Dan

#9 coutleef

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Posted 23 January 2013 - 01:44 PM

i previously used a ethos 17mm with my C8. the biggest advantage was being able to look at star clusters at 120x without trouble to frame most of them. Big advantage when you view from the city as the stars are seen on a black background not a grey one like when you use a lower power. you do not ise the complete FOV but look at your object without seeing the field stop. it gives you the impression of floating into space.

the downside: i lost the feeling and now prefer 70degrees EPs. also be aware that with a 20mm, stars will be out of focus at the periphery because of the field curvature of your scope that will be visible in that wide field ep but not with the 70 degrees EPs. this i think is one reason why SCT users prefer panoptics or Pentax to wider fov EPs.

for your information, i preferred the 20t5 to the etos and if you want to send money on an ep of that focal lengrh itis a good one.

do you use a focal reducer with your scope

#10 mitaccio

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Posted 23 January 2013 - 01:55 PM

I don't have a focal reducer *yet*. May get one this next week. My biggest concern is clearance at zenith as I am also planning to get a 2" WO diagonal.

I have to say, I find 82 degrees to be massive and have not viewed through a 100 degree eyepiece, so I have no idea what the hype is. Having a goto mount, I have questioned the need. I do like that I can spend more time looking around with my 82s when I don't do a good alignment job though.

I am now looking into Delos, too bad they max out at 17mm for now.

#11 coutleef

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Posted 23 January 2013 - 03:15 PM

I don't have a focal reducer *yet*. May get one this next week. My biggest concern is clearance at zenith as I am also planning to get a 2" WO diagonal.

I have to say, I find 82 degrees to be massive and have not viewed through a 100 degree eyepiece, so I have no idea what the hype is. Having a goto mount, I have questioned the need. I do like that I can spend more time looking around with my 82s when I don't do a good alignment job though.

I am now looking into Delos, too bad they max out at 17mm for now.


the logic with televue is to buy delos below 20mm and panoptics above 20mm. the panoptic 35 is a very nice EP with a c8.

using a focal redicer changes your choice of EPs as the focal lengrh of your scope changes






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