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#1 Enceladust

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Posted 26 February 2021 - 12:08 AM

I do not yet own eyepieces with a huge FOV. Like 100 degrees, etc... I wish I could have that! Yet sometimes I see some people commenting that it's "too much" for them.

 

How can that be?


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#2 AtlantaAstro

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Posted 26 February 2021 - 12:15 AM

It’s just a matter of preference. Some people like wide field of view, some don’t. Especially when it comes to certain magnifications. Some people like high magnification, 52° field of view for planets. Some people want to feel like they’re swimming in space. Also, certain objects will only fit in those wide fields such as the Adromeda galaxy


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#3 f74265a

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Posted 26 February 2021 - 12:23 AM

First, you cannot take in the whole image at once. You have yo move your head around. A lot. Also, it is easy to get distracted by other stuff in your fov instead of focusing on one point. That said, they make life so much better with a non tracking mount
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#4 Enceladust

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Posted 26 February 2021 - 12:24 AM

It’s just a matter of preference. Some people like wide field of view, some don’t. Especially when it comes to certain magnifications. Some people like high magnification, 52° field of view for planets. Some people want to feel like they’re swimming in space. Also, certain objects will only fit in those wide fields such as the Adromeda galaxy

I guess when you have a tracking telescope you don't care as much, I wish I'd be swimming in space with my dob and minimize the moments when I have to move it to follow things!


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#5 Enceladust

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Posted 26 February 2021 - 12:26 AM

First, you cannot take in the whole image at once. You have yo move your head around. A lot. Also, it is easy to get distracted by other stuff in your fov instead of focusing on one point. That said, they make life so much better with a non tracking mount

I did not see that response when I posted my latest reply, it makes a lot of sense! thank you!!



#6 scotsman328i

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Posted 26 February 2021 - 12:31 AM

It’s just a matter of preference. Some people like wide field of view, some don’t. Especially when it comes to certain magnifications. Some people like high magnification, 52° field of view for planets. Some people want to feel like they’re swimming in space. Also, certain objects will only fit in those wide fields such as the Adromeda galaxy

I agree, it depends on the application. I find I want 80+ AFOV for eyepieces 13mm and longer for wide field viewing of clusters, Star fields, nebulae and such. When it comes to planetary and lunar, I prefer the brightest and sharpest views possible. This usually comes with a sacrifice of less optical elements over the many elements of glass that make a staggering wide field eyepiece that make the AFOV much larger. I’m not trying to stretch out an AFOV when viewing high power on planetary and lunar details as my primary focus is on the object, not the surrounding starfields around it. Make sense? 


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#7 Enceladust

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Posted 26 February 2021 - 12:35 AM

I agree, it depends on the application. I find I want 80+ AFOV for eyepieces 13mm and longer for wide field viewing of clusters, Star fields, nebulae and such. When it comes to planetary and lunar, I prefer the brightest and sharpest views possible. This usually comes with a sacrifice of less optical elements over the many elements of glass that make a staggering wide field eyepiece that make the AFOV much larger. I’m not trying to stretch out an AFOV when viewing high power on planetary and lunar details as my primary focus is on the object, not the surrounding starfields around it. Make sense? 

This also makes total sense! thank you :) 


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#8 f74265a

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Posted 26 February 2021 - 12:46 AM

I agree, it depends on the application. I find I want 80+ AFOV for eyepieces 13mm and longer for wide field viewing of clusters, Star fields, nebulae and such. When it comes to planetary and lunar, I prefer the brightest and sharpest views possible. This usually comes with a sacrifice of less optical elements over the many elements of glass that make a staggering wide field eyepiece that make the AFOV much larger. I’m not trying to stretch out an AFOV when viewing high power on planetary and lunar details as my primary focus is on the object, not the surrounding starfields around it. Make sense?


For those of us on nontracking mounts the 3.7E makes for a very serviceable planetary eyepiece with huge drift time
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#9 scotsman328i

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Posted 26 February 2021 - 12:51 AM

For those of us on nontracking mounts the 3.7E makes for a very serviceable planetary eyepiece with huge drift time

Yes! This type of eyepiece is a worthy note! TeleVue and a few others have come up with the solution to very high power viewing AND keeping a huge AFOV in an eyepiece also. This is actually an incredible experience to have a huge field to view with under very high power and present amazing optical performance...however, be wary! These oculars come with a huge price! If you wanted a package all wrapped up onto one, the TeleVue Ethos Simulator Experience sub 5mm eyepieces are the way to go.


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#10 havasman

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Posted 26 February 2021 - 01:20 AM

I have very little trouble seeing the entire field of my Ethos without the contortions some report. I never think about it when observing but have tested this just to check for purposes of these discussions.

 

My most used scope tracks. The mounts for the NP101is don't. Ethos are my primary eyepieces in both scopes. For me the freedom from being at all concerned with the field stop and the luxurious framing of objects are real benefits. I don't have the 17 or the 8. All the rest of them are valuable contributors to different observations. I am most excited by galaxy observing in the 16" and these eyepieces are major contributors. Clusters of small relatively faint galaxies are well presented at magnifications that allow them to be well seen in fields that present them in context which is extremely beneficial for identifying them and hopping between the groups' members. My favorites are the 6 (350x and 17 arc') and 4.7 (446x and 15 arc') for these purposes. The fields presented in my Dobs with a Paracorr 2 in place are really fine.

 

With the fast Petzval refractor the benefit of the pristine well corrected fields presented by the longer focal length Ethos is obvious. Since I have been using it in this scope I have come to think the 21E is the highest performance eyepiece I have ever used. Though it's not my favorite eyepiece it may likely be the best eyepiece I will ever have.

 

Some folks don't like the hyperwide fields. Others just cannot justify them. Some hate them on principle though they have never used one. Their logic is also correct for them.

 

I also enjoy using my 68 degree AFOV and 44 degree AFOV eyepieces for special purposes.

 

Eyepieces are quite subjective and individual. One's face may not match the profile that best fits an eyepiece. One may not like the way an eyepiece handles in the field. Someone may observe planets from a balcony in a major city while somebody else may observe faint old planetaries from NW Arizona. Some use 14" f3 reflectors and others may use 4" f12 refractors. Others have big scopes. All that matters a lot.

 

So no. It's fairly unlikely anyone can explain it well enough any more than you can explain Bach to those unable to hear or cerulean to those unable to see.


Edited by havasman, 26 February 2021 - 10:29 PM.

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#11 SeattleScott

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Posted 26 February 2021 - 02:04 AM

At first I found I had to move my head around to take in the whole field of view. Eventually I found if I get my eye close enough then I can see the whole view, at least with the 13 Ethos. I hear some other hyperwides require moving the head to see the whole view, idk, only used Ethos. But being used to long ER eyepieces where my glass is normally safe beyond the maximum range of my eyelashes, I find it a little uncomfortable taking in the entire FOV with Ethos. Like I have to intentionally not blink. Granted most of the time 80-90 AFOV is good enough to frame a target and allow one to keep their eyelashes a safe distance.

Another issue is size and weight, although the Ethos are not as bad in that respect as some, especially at certain focal lengths. But a 13 ethos is still a lot bigger than a 13T6 or something.

Eye relief is crucial to me as I often wear glasses while observing. Doesn’t really work great with hyperwides.

And if you get close enough to take in the whole field, it is so big you kind of have to look around to focus on different parts of it. Now I’m clearly nitpicking.

So I get it, 25585 needs more eye relief. Bill doesn’t like how big and heavy they are. They aren’t for everyone. But if you have a big, manual Dob, don’t wear glasses while observing, and don’t object to the size/weight, they are pretty cool.

And yes there are the minimum glass types. Especially for small targets like galaxies, you don’t exactly need 100 AFOV, especially with a tracking mount. I count myself among this group but only for planetary viewing.

So yeah there are some legitimate reasons some people don’t care much for them. Personally I don’t own any although I borrow some now and then. I like them, when I’m not wearing glasses anyway. Might get an APM XWA. Ethos are out of my price range.

Scott
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#12 213Cobra

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Posted 26 February 2021 - 04:24 AM

Age can be a factor.

 

I am thoroughly comfortable with 82° AFOV eyepieces. I can take in the full view or what little I cannot, requires only minimal eyeball rolling to scan the complete perimeter of the field. At 90° I feel I don't want more but happy to have gotten there. At 100-110° AFOV, moving my head seems more awkward (or as the kids say "awks") than rolling my eyeball around the perimeter of the view field to see everything. This gets quickly fatiguing. I can't say for sure it would have been less fatiguing when I was 26, because then an 82° eyepiece was a revelation. At 66 however, since eye muscle fatigue also can choke visual acuity, what's the point? I don't go wider AFOV than my Takahashi UW 90° eyepieces.

 

Phil


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#13 izar187

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Posted 26 February 2021 - 07:07 AM

I don't think they're any good at all.

Pretty sure they all sound too heavy, too expensive, too hard to look through.

 

I'm holding out for 145 degree fov type, with 20mm eye relief, delrin bodies and plastic lenses for weight, astigmastism and coma correction built in, down to f/4.

 

Then they'll be ok, but otherwise they're not. : )


Edited by izar187, 26 February 2021 - 07:07 AM.


#14 Jon Isaacs

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Posted 26 February 2021 - 07:30 AM

I agree, it depends on the application. I find I want 80+ AFOV for eyepieces 13mm and longer for wide field viewing of clusters, Star fields, nebulae and such. When it comes to planetary and lunar, I prefer the brightest and sharpest views possible. This usually comes with a sacrifice of less optical elements over the many elements of glass that make a staggering wide field eyepiece that make the AFOV much larger. I’m not trying to stretch out an AFOV when viewing high power on planetary and lunar details as my primary focus is on the object, not the surrounding starfields around it. Make sense? 

 

That has not been my experience.  I see you scope range from F/5 to about F/7.  Such scope require short focal length eyepieces for viewing the planets. 

 

The sharpest planetary views are primarily about seeing that allow the use of relatively high magnifications.  In my 13.1 inch F/5.5, a 5mm eyepiece provides 420x, a 7mm eyepiece provides 300x.  If one is using short focal length eyepieces, unless the eyepiece is a negative-positive design, eye relief will be so short as not only be uncomfortable but the eye lens will likely be contaminated with eyelash fluid.  

 

With a tracking mount, it can work but for manual tracking, an Ethos or Nagler combined with a Paracorr or other coma corrector provides a large, well correct sweet spot that can be essentially the entire field of view.  That is not happening with simple 3 and 4 element eyepieces, their sweet spots are not small.. 

 

In terms of AFoV, I find the 100 degree field of view most valuable in larger scopes. This is because one is working at proportionally higher magnifications so the field of view is proportionally smaller for a given exit pupil.  In a 10 inch, a 2mm exit pupil is 125x and a 50 degree eyepiece provides a 0.40 TFoV,  in the 22 inch, it's 280x and a 50 degree eyepiece provides a 0.18 degree field of view, that's about 10 arc-minutes. 

 

Jon



#15 MartinPond

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Posted 26 February 2021 - 07:51 AM

I do not yet own eyepieces with a huge FOV. Like 100 degrees, etc... I wish I could have that! Yet sometimes I see some people commenting that it's "too much" for them.

 

How can that be?

 

Past about 60 degrees, I find that the large image plane is distracting,

   and the contrast is reduced.   I think the contrast part might have to do

   with the large image plane putting more light into my eye's vitreous.

 

That said, I have been  learning how to enjoy 80 degrees lately,

  for smaller nebulae.  It's in what you look at, and with what.

 

 A 60-deg choked 1,2,1  (like the Paradigm lately) can make the whole field

   a sweet spot, resolution-wise, if the 'apparent' barrel is over F15.

   Not so hard to attain:  a Paradigm 15mm  in an F10 with 2X Barlow  (F20 equiv).

   The top section is a 4-element eyepiece, the bottom is simply a Barlow 

     (just adds to that F20).


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#16 Magnetic Field

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Posted 26 February 2021 - 07:55 AM

That has not been my experience.  I see you scope range from F/5 to about F/7.  Such scope require short focal length eyepieces for viewing the planets. 

 

The sharpest planetary views are primarily about seeing that allow the use of relatively high magnifications.  In my 13.1 inch F/5.5, a 5mm eyepiece provides 420x, a 7mm eyepiece provides 300x.  If one is using short focal length eyepieces, unless the eyepiece is a negative-positive design, eye relief will be so short as not only be uncomfortable but the eye lens will likely be contaminated with eyelash fluid.  

 

With a tracking mount, it can work but for manual tracking, an Ethos or Nagler combined with a Paracorr or other coma corrector provides a large, well correct sweet spot that can be essentially the entire field of view.  That is not happening with simple 3 and 4 element eyepieces, their sweet spots are not small.. 

 

In terms of AFoV, I find the 100 degree field of view most valuable in larger scopes. This is because one is working at proportionally higher magnifications so the field of view is proportionally smaller for a given exit pupil.  In a 10 inch, a 2mm exit pupil is 125x and a 50 degree eyepiece provides a 0.40 TFoV,  in the 22 inch, it's 280x and a 50 degree eyepiece provides a 0.18 degree field of view, that's about 10 arc-minutes. 

 

Jon

We have to put things into perspective here.

 

People should go back to basics (this means one and only on number: the physical field stop and resulting true max field of view).

 

Everything below 1 degree true field of view is really basic and quite a drag on one's heel when observing deep sky objects.

 

Yes I understand with larger telescopes (>8") reaching a big true field of view at a decent magnification is hard to realise.

 

Although if the true field of view becomes too big (probably > 2 or 2.5 degrees) it is no fun either for the majority of objects.


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#17 scotsman328i

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Posted 26 February 2021 - 08:51 AM

That has not been my experience.  I see you scope range from F/5 to about F/7.  Such scope require short focal length eyepieces for viewing the planets. 

 

The sharpest planetary views are primarily about seeing that allow the use of relatively high magnifications.  In my 13.1 inch F/5.5, a 5mm eyepiece provides 420x, a 7mm eyepiece provides 300x.  If one is using short focal length eyepieces, unless the eyepiece is a negative-positive design, eye relief will be so short as not only be uncomfortable but the eye lens will likely be contaminated with eyelash fluid.  

 

With a tracking mount, it can work but for manual tracking, an Ethos or Nagler combined with a Paracorr or other coma corrector provides a large, well correct sweet spot that can be essentially the entire field of view.  That is not happening with simple 3 and 4 element eyepieces, their sweet spots are not small.. 

 

In terms of AFoV, I find the 100 degree field of view most valuable in larger scopes. This is because one is working at proportionally higher magnifications so the field of view is proportionally smaller for a given exit pupil.  In a 10 inch, a 2mm exit pupil is 125x and a 50 degree eyepiece provides a 0.40 TFoV,  in the 22 inch, it's 280x and a 50 degree eyepiece provides a 0.18 degree field of view, that's about 10 arc-minutes. 

 

Jon

I dunno what to tell you, Jon. I’ve had none of those issues of uncomfortable eye placement and eyelash fluid smearing my optical surface. Granted tighter eye relief indeed but useable to my eye as I don’t wear glasses at the eyepiece. Most of my designs sit between 45-68 degrees or so for high power viewing and the eye relief I gather you’d know the numbers for better than I would off the top of your head compared to me researching those numbers, but I’ve found the eye relief manageable with my Orthos and Pentax, but then again...I don’t wear glasses when I actually observe through the eyepiece. Plus, you’re writing that from a very critical observer, which I’m not. I PERSONALLY don’t mind the tighter FOV and shorter eye relief in some of the high power focal lengths I own. I also understand YMMV. However you did hit the nail on the head that with the telescope focal lengths I own, I do require short focal length eyepieces and I use the Baader Planetarium Orthos and Pentax XL and XF smc eyepieces to tackle those applications.

 

*NOTE* BTW, I may have the Pentax 10.5 XL smc coming to me also. Waiting for the seller to answer my PM. 


Edited by scotsman328i, 26 February 2021 - 09:09 AM.


#18 Jon Isaacs

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Posted 26 February 2021 - 09:16 AM

We have to put things into perspective here.

 

People should go back to basics (this means one and only on number: the physical field stop and resulting true max field of view).

 

Everything below 1 degree true field of view is really basic and quite a drag on one's heel when observing deep sky objects.

 

Yes I understand with larger telescopes (>8") reaching a big true field of view at a decent magnification is hard to realise.

 

Although if the true field of view becomes too big (probably > 2 or 2.5 degrees) it is no fun either for the majority of objects.

 

The basics are exit pupil and magnification.  Those are the fundamental parameters that determine what you see in the eyepiece.  

 

Field of view is second order and effective AFoV is important because it provide larger TFOVs at a given magnification.

 

The TFoV is always relative to the view desired.  When viewing a 14th magnitude galaxy that's 2' in diameter at 300x, the value of a wide TFoV is in finding the object and then for a manually tracked scope, the drift time across the field of view.

 

Other times, a 4 degree field is about right, framing the Veil or the Pelican-NorthAmerican Complex with a large exit pupil is about right.  And for objects like Barnard's loop, an even wider field with a near maximum exit pupil seems best to me.

 

Jon


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#19 Jon Isaacs

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Posted 26 February 2021 - 09:20 AM

I dunno what to tell you, Jon. I’ve had none of those issues of uncomfortable eye placement and eyelash fluid smearing my optical surface. Granted tighter eye relief indeed but useable to my eye as I don’t wear glasses at the eyepiece. Most of my designs sit between 45-68 degrees or so for high power viewing and the eye relief I gather you’d know the numbers for better than I would off the top of your head compared to me researching those numbers, but I’ve found the eye relief manageable with my Orthos and Pentax, but then again...I don’t wear glasses when I actually observe through the eyepiece. Plus, you’re writing that from a very critical observer, which I’m not. I PERSONALLY don’t mind the tighter FOV and shorter eye relief in some of the high power focal lengths I own. I also understand YMMV. However you did hit the nail on the head that with the telescope focal lengths I own, I do require short focal length eyepieces and I use the Baader Planetarium Orthos and Pentax XL and XF smc eyepieces to tackle those applications.

 

*NOTE* BTW, I may have the Pentax 10.5 XL smc coming to me also. Waiting for the seller to answer my PM. 

 

I don't wear glasses at the eyepiece either.  If you are using 60 degree eyepieces, they probably have sufficient eye relief. But if you are using 3mm and 5mm eyepieces like Orthos, the eye relief is very short.  

 

Jon


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#20 Magnetic Field

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Posted 26 February 2021 - 09:32 AM

The basics are exit pupil and magnification.  Those are the fundamental parameters that determine what you see in the eyepiece.  

 

Field of view is second order and effective AFoV is important because it provide larger TFOVs at a given magnification.

 

The TFoV is always relative to the view desired.  When viewing a 14th magnitude galaxy that's 2' in diameter at 300x, the value of a wide TFoV is in finding the object and then for a manually tracked scope, the drift time across the field of view.

 

Other times, a 4 degree field is about right, framing the Veil or the Pelican-NorthAmerican Complex with a large exit pupil is about right.  And for objects like Barnard's loop, an even wider field with a near maximum exit pupil seems best to me.

 

Jon

Reminds me when people write dissertations and Phds for the right cassette gear spacings and ratios when out road cycling. I always think what a waste of time for a hobby cyclist.

 

Of course exit pupil is a deciding factor but I don't care about exit pupil as long as it is over 1mm.

 

Although I care about magnification if I am honest.

 

Again: forget all that 100 degree crap. The field stop and true field of view counts.

 

All what a 100 degree number tells you: you may have problems with field edge sharpness and some people don't like too much of a field.

 

Coming back to my own post #131 here: One may think a whopping 20 degrees difference in apparent field of view (60 vs 80 degrees) but in the end of the day the difference is fairly modest in terms of true field thanks to only 1.3mm difference in field stop diameter (although slightly cheating with magnification here 13mm vs 15mm):

 

https://www.cloudyni...lue/?p=10911156



#21 scotsman328i

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Posted 26 February 2021 - 09:36 AM

I don't wear glasses at the eyepiece either.  If you are using 60 degree eyepieces, they probably have sufficient eye relief. But if you are using 3mm and 5mm eyepieces like Orthos, the eye relief is very short.  

 

Jon

Oh I agree, the eye relief is short on a couple of those Baader Orthos (I believe 5mm eye relief on the 6 Ortho, then around 8mm eye relief on the 10 Ortho and 15mm eye relief or so with the 18 Ortho), but the views are very sharp, contrasty and bright. I really love the views they present. The 10 and 18 Orthos don’t bother me, but I do struggle a bit with the 6 Ortho, that’s why I found a good deal on the Pentax 5.2mm XL smc to basically replace it. 


Edited by scotsman328i, 26 February 2021 - 09:37 AM.

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#22 scotsman328i

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Posted 26 February 2021 - 09:43 AM

Oh I agree, the eye relief is short on a couple of those Baader Orthos (I believe 5mm eye relief on the 6 Ortho, then around 8mm eye relief on the 10 Ortho and 15mm eye relief or so with the 18 Ortho), but the views are very sharp, contrasty and bright. I really love the views they present. The 10 and 18 Orthos don’t bother me, but I do struggle a bit with the 6 Ortho, that’s why I found a good deal on the Pentax 5.2mm XL smc to basically replace it. 

Oh, BTW Jon, the seller just got back to me, I got the Pentax 10.5 XL smc! grin.gif


Edited by scotsman328i, 26 February 2021 - 09:53 AM.

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#23 Jon Isaacs

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Posted 26 February 2021 - 10:01 AM

Reminds me when people write dissertations and Phds for the right cassette gear spacings and ratios when out road cycling. I always think what a waste of time for a hobby cyclist.

 

Of course exit pupil is a deciding factor but I don't care about exit pupil as long as it is over 1mm.

 

Although I care about magnification if I am honest.

 

Again: forget all that 100 degree crap. The field stop and true field of view counts.

 

All what a 100 degree number tells you: you may have problems with field edge sharpness and some people don't like too much of a field.

 

Coming back to my own post #131 here: One may think a whopping 20 degrees difference in apparent field of view (60 vs 80 degrees) but in the end of the day the difference is fairly modest in terms of true field thanks to only 1.3mm difference in field stop diameter (although slightly cheating with magnification here 13mm vs 15mm):

 

 

I have done my fair share of cycling and done my best to maximize whatever meager performance I myself was able to achieve.  I put together close ratio cog sets for flat time trials and 20-34 low gears for extended climbs off-road.  

 

5637152-Jon at Fiesta Island 1.jpg

 

Observing and cycling share many similarities.  Small differences can be important.  And some factors are critical in some circumstances and not in others.  

 

There are real differences visible between a 15mm eyepiece and a 13mm eyepiece. The 15mm is 33% brighter, that can be an advantage or disadvantage.  

 

Sometime TFOV is important, sometimes it is only of peripheral importance.  Some objects require exit pupils well under 1mm.. 

 

It all comes down to what one sees in the eyepiece.  Understanding why,,, that is part of observing.  

 

Jon  


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#24 Magnetic Field

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Posted 26 February 2021 - 10:14 AM

I have done my fair share of cycling and done my best to maximize whatever meager performance I myself was able to achieve.  I put together close ratio cog sets for flat time trials and 20-34 low gears for extended climbs off-road.  

 

 

 

Observing and cycling share many similarities.  Small differences can be important.  And some factors are critical in some circumstances and not in others.  

 

There are real differences visible between a 15mm eyepiece and a 13mm eyepiece. The 15mm is 33% brighter, that can be an advantage or disadvantage.  

 

Sometime TFOV is important, sometimes it is only of peripheral importance.  Some objects require exit pupils well under 1mm.. 

 

It all comes down to what one sees in the eyepiece.  Understanding why,,, that is part of observing.  

 

Jon  

I know John.

 

This were the times back then. I remember you from rec.bicycles.tech in the good old deja new days. Anyone remember Jobst Brandt?



#25 cst4

cst4

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Posted 26 February 2021 - 10:50 AM

XWA eyepieces are pretty awesome, but they're not for everyone.  My biggest complaint is that they are too large and bulky...  My 3.5mm and 20mm APM HDC's probably take up more room than my entire set of orthos, plossls, and konigs combined.  They are lightweight for their large size but still heavy enough to cause me balance issues sometimes.  Plus the 3.5mm is simply so tall it won't fit in my case.  So I find their size annoying. 

 

Also, the view is so large you can't really take it all in at once.  This can make for a nice porthole to space affect, but it takes effort to move your head around and see more sky.  I prefer just to nudge the scope and get the view centered again most of the time.  The view is usually sharpest in the center anyway.  Plus, I find that there is often a sort of chromatic aberration experience that I see when I try to look towards the edge of some XWA or even UWA eyepieces.  I see colors that I think are caused by the viewing angle.  I can sometimes kind of make them go away by adjusting my eye or head position but I don't care for this experience.  It doesn't happen with smaller FOV eyepieces.

 

BUT... I will say... The 20mm XWA gave me some amazing views before I sold it off because of it's large size.  And the 3.5mm over doubled my drift time at 200x in my refractor compared to the 3.5mm LVW I was using before it while also providing great views of the planets.  So they are pretty great and nice to use... I just learned they weren't for me.  I'll stick to my Morphei where I can still easily take in the whole view and not deal with the other issues I mentioned.


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