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9mm Eyepieces You'd Sacrifice Eye Relief For

cassegrain eyepieces
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#1 Spacefreak1974

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Posted 21 March 2019 - 01:41 PM

I'm still on the hunt for a good eyepiece for my 8" SCT. I have a few of the ES 82's 11 and 30mm as well as I have one of the Morpheus (14mm). The 14mm Morpheus and the 30mm ES 82 have 20+mm eye relief and they are comfortable with glasses. My first year of serious observing I took my glasses off and he past two years i've trained myself to leave them on. I'm thinking maybe it might be worth it to take them off once and a while if there's an eyepiece i'm missing out on that might not have the 20mm eye relief for use with glasses

 

Thoughts?

 

I've heard a lot of rants and raves about the APM XWA HDC 9mm 100mm AFOV

Are there others I should sacrifice eye relief and go with?

 

Also have considered the 9mm Morpheus and 8mm Delos considering the eye relief for wearing glasses

 

Some folks on here are probably just ...Dangit Jon just buy something!

 

Jon


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#2 Jeff Struve

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Posted 21 March 2019 - 01:45 PM

I never wear my glasses when doing visual astronomy and would never consider it.



#3 CrazyPanda

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Posted 21 March 2019 - 01:51 PM

At F/10, a 9mm eyepiece will produce a 0.9mm exit pupil. Unless you have very severe astigmatism, you shouldn't notice any problems at this exit pupil. Thus I would argue glasses aren't necessary here. 

It's just a matter of whether or not you find taking your glasses on and off is too much hassle or not. 



#4 dusty99

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Posted 21 March 2019 - 01:55 PM

I had the Morpheus, and it was good.  I only sold it because it was too close to my Delos 10mm and therefore felt redundant.  The Delite comes in a 9mm.  I'm a glasses wearer and will take them off for one of my orthos, but like to be able to leave them on if I'm hunting for something or just scanning.  The Meade 8.8mm UWA is pretty good and has 15mm ER.  Between it, the Morheus and the Delite, there's not much reason to get a short ER eyepiece, IMO.



#5 Mr. Mike

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Posted 21 March 2019 - 02:00 PM

Hmmm.  Tough call that probably only you can make.  Even though I dont wear glasses when viewing(Im near sighted) and dont have any astigmatism issues I still prefer eye relief in my eyepieces to be fairly plentiful.  With widefields I feel this is even more important but thats just me.  I too am very curious about the APM 100 degree EP in 9mm but Im leaning toward the Morpheus due to the eye relief!  Yeah, I lose a 1/4 of the AFOV but the comfort and ability to hopefully see more of the field without my eyelashes touching the lens is a big plus to me.

 

Maybe Im wrong here but with ultra-wide EPs, dont you need some extra eye relief for comfort and usability?



#6 izar187

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Posted 21 March 2019 - 02:00 PM

Go with an ep with glasses on eye relief.

There is just no reason not to, as there are so many good ones available nowadays.



#7 Luca Brasi

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Posted 21 March 2019 - 02:06 PM

I've never tried a Baader eyepiece, but their filters are phenomenal! But I can tell you that the Delos line are perfectly designed and amazingly sharp. I would own a whole line of Delos if I didn't already own the ES 100 line. I feel like every eyepiece should have an adjustable cup!
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#8 sg6

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Posted 21 March 2019 - 02:35 PM

Why 20mm?

I wear glasses and get along happily with Paradigms and they are given as 16-17mm eye relief.

 

Just thinking that there are likely a fair number of 18mm to 20mm which you may be excluding. Have also said that in optics the measurements should be from the "optical center" of the lens. Assuming the top lens is a fairly chunky doublet then the optical center could be 3mm below the surface.

 

20mm eye relief measured from the optical center (say 3mm inside the top lens) is 17mm from the top surface.

18mm eye relief measured from the top surface is 18mm.

So the 18mm has more eye relief then the 20mm.

 

Now it would make sense (a rare commodity) to give a measurement from the top surface but they do not have to and are still correct. And a measurement from the optical center makes a bigger value and more sales. In optics there are quite a few ambiguous areas. And to my mind eye relief is one of them.



#9 Spacefreak1974

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Posted 21 March 2019 - 03:03 PM

Why 20mm?

I wear glasses and get along happily with Paradigms and they are given as 16-17mm eye relief.

 

Just thinking that there are likely a fair number of 18mm to 20mm which you may be excluding. Have also said that in optics the measurements should be from the "optical center" of the lens. Assuming the top lens is a fairly chunky doublet then the optical center could be 3mm below the surface.

 

20mm eye relief measured from the optical center (say 3mm inside the top lens) is 17mm from the top surface.

18mm eye relief measured from the top surface is 18mm.

So the 18mm has more eye relief then the 20mm.

 

Now it would make sense (a rare commodity) to give a measurement from the top surface but they do not have to and are still correct. And a measurement from the optical center makes a bigger value and more sales. In optics there are quite a few ambiguous areas. And to my mind eye relief is one of them.

Sure and I would still call 17 relatively long eye relief, but the APM XWA HDC on the 9mm has 13mm eye releief



#10 jaraxx

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Posted 21 March 2019 - 03:26 PM

I don't wear glasses for viewing, and I use the 9mm Morpheus. I think I can promise that you won't regret buying a 9mm Morpheus because of the view. Were I you, I'd want to keep the consistency - so I'd go with eyepieces that let me preserve my customary practice over one that's an aberration. I find eyeglasses on then off annoying, one more thing to keep up with. 


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#11 spaceoddity

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Posted 21 March 2019 - 04:21 PM

I have a bunch of 82 degree eyepieces and a couple 100's on the way for use in my dobs and maybe my refractor on an a manual alt/az mount but I don't know why one needs a 100 degree eyepiece or even 82 for a scope that has tracking and go-to. Nothing wrong with it I suppose but when I got an 8" SCT last summer I went the other direction and picked up a baader ortho and a meade hd60 specifically for higher power use in that scope. It's good to max out the fov at low power but for high power it's kind of a waste if your scope has tracking. 



#12 25585

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Posted 21 March 2019 - 05:38 PM

None for 9mm. But go up to 10mm and its the Nikon 12.5 HW with EiC-10 extender fitted.



#13 earlyriser

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Posted 21 March 2019 - 05:49 PM

I only put up with short eye relief on my 9mm Tak Abbe Ortho. With modern designs, there's no compelling reason to live with short eye relief. Especially below 10mm. 


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#14 Lt 26

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Posted 21 March 2019 - 08:11 PM

Ethos 8mm. I need a minimum of 15mm without glasses. A great under one pound eyepiece.

Dereck

#15 Spacefreak1974

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Posted Today, 11:34 AM

I ordered the 9mm Morpheus!


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