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#1 Mishulya

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Posted 27 October 2020 - 09:22 PM

Hello!

I have a 10in f/4.7 Dob on the way. So far, I have ordered one eyepiece in anticipation of its arrival. The EP that I have is the Baader 1.25" and 2" Morpheus 76° Wide-Field Eyepiece - 12.5mm.

Something that I am having a hard time understanding is the general utility of a 2" EP.

I would obviously like to add a higher magnification EP to my arsenal, so I am debating whether or not to order a separate EP, or to get a 2x barlow for the Morpheus. I hope this question makes any sense at all. Thanks in advance for any replies!



#2 N3p

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Posted 27 October 2020 - 09:31 PM

This might help, the relation between the apparent field of view of the EP, the focal length of the EP and the dimension of the barrel 1.25" and 2"

 

p5t8Iyu.png


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#3 vtornado

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Posted 27 October 2020 - 09:37 PM

At least one two inch eyepice is good to own.   It is a finder eyepiece, and a widefield viewing eyepiece.   I have found the GSO superview

ok at f 4.7.  Yes the edges are messy, but you have to spend 3x or more to get significantly better views.  And since I am in bortle 7

wide views are underwhelming due to a washed out sky.

 

A 32mm1.25 inch  plossl eyepice has a field of view of about 1.2 degrees, a 2 inch 30mm eyepiece will be about 2.1, that is

roughly 3x more sky.


Edited by vtornado, 27 October 2020 - 09:41 PM.

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#4 Mishulya

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Posted 27 October 2020 - 09:41 PM

This might help, the relation between the apparent field of view of the EP, the focal length of the EP and the dimension of the barrel 1.25" and 2"

 

p5t8Iyu.png

Thanks for this!


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#5 Mishulya

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Posted 27 October 2020 - 09:42 PM

At least one two inch eyepice is good to own.   It is a finder eyepiece, and a widefield viewing eyepiece.   I have found the GSO superview

ok at f 4.7.  Yes the edges are messy, but you have to spend 3x or more to get significantly better views.  And since I am in bortle 7

wide views are underwhelming due to a washed out sky.

 

A 32mm1.25 inch  plossl eyepice has a field of view of about 1.2 degrees, a 2 inch 30mm eyepiece will be about 2.1, that is

roughly 3x more sky.

So for a higher powered EP, I should look into a 4-6mm 1.25?



#6 Bistromath

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Posted 27 October 2020 - 09:58 PM

So for a higher powered EP, I should look into a 4-6mm 1.25?

In your scope, a 4mm eyepiece will produce close to 300x magnification.  At magnification levels this high, you likely will be limited on how many nights you will get a clear view with the eyepiece.  It will depend on the seeing conditions for your observing location.

 

Other than the Morpheus, will you have any other eyepieces, such as those that may have been included with the scope?

 

If you do not have a low power eyepiece coming with the scope, you may want to consider getting one along with a 2x barlow.  You can use the barlow with your Morpheus to get ~190x magnification for high-power views of planets and the moon.  A low power eyepiece is useful for globular clusters, large nebulas, etc.  You can also use the barlow with the low power eyepiece and in essence with 2 eyepieces and a barlow, you will get four different levels of magnification to choose from.


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#7 vtornado

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Posted 27 October 2020 - 10:15 PM

A 5mm paradigm dual ed eypiece works very well in your scope.  I had a 4.7 250mm dob and it was a great eyepiece.

I still have the eyepiece but sold the scope.

 

BTW magnification = telescope_focal_length / eyepiece_focal_length.   So in your scope a 5mm eyepiece is

1200 / 5 = 240x. 

 

Don't go whole hog all at once,   get your stuff observe a variety of objects, and see what would make your viewing better.

 

Depending upon your seeing conditions, eyes, brain, likes and dislikes it is hard to know what equipment works best for you.


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#8 JoshUrban

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Posted 27 October 2020 - 10:47 PM

Yeah, a 4mm is pushing it.  It's nice to have, but my 7mm gets way more use in my 12.5" dob.  WAY more.  A 9mm might even be the way to go.  And, regarding 2" eyepieces - they are AWESOME.  It's hard to tell just by reading the description, but the experience is so nice (and that's why I observe.)  A used Panoptic on the classifieds is worth shelling out for in my opinion.  And, some of the older Naglers come up for "cheap" (compared to the new ones!) too!  

 

  As with anything, you don't NEED any gear to enjoy the sky, but I think you'd dig a 2" eyepiece at some point.  I know I sure do.  


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#9 Mishulya

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Posted 27 October 2020 - 11:28 PM

Yeah, a 4mm is pushing it.  It's nice to have, but my 7mm gets way more use in my 12.5" dob.  WAY more.  A 9mm might even be the way to go.  And, regarding 2" eyepieces - they are AWESOME.  It's hard to tell just by reading the description, but the experience is so nice (and that's why I observe.)  A used Panoptic on the classifieds is worth shelling out for in my opinion.  And, some of the older Naglers come up for "cheap" (compared to the new ones!) too!  

 

  As with anything, you don't NEED any gear to enjoy the sky, but I think you'd dig a 2" eyepiece at some point.  I know I sure do.  

Thanks, Josh! I do have a 2" 12.5mm EP, it just arrived yesterday! Still waiting on the scope, though...


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#10 Mishulya

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Posted 27 October 2020 - 11:28 PM

A 5mm paradigm dual ed eypiece works very well in your scope.  I had a 4.7 250mm dob and it was a great eyepiece.

I still have the eyepiece but sold the scope.

 

BTW magnification = telescope_focal_length / eyepiece_focal_length.   So in your scope a 5mm eyepiece is

1200 / 5 = 240x. 

 

Don't go whole hog all at once,   get your stuff observe a variety of objects, and see what would make your viewing better.

 

Depending upon your seeing conditions, eyes, brain, likes and dislikes it is hard to know what equipment works best for you.

Good advice, thank you!



#11 Mishulya

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Posted 27 October 2020 - 11:29 PM

In your scope, a 4mm eyepiece will produce close to 300x magnification.  At magnification levels this high, you likely will be limited on how many nights you will get a clear view with the eyepiece.  It will depend on the seeing conditions for your observing location.

 

Other than the Morpheus, will you have any other eyepieces, such as those that may have been included with the scope?

 

If you do not have a low power eyepiece coming with the scope, you may want to consider getting one along with a 2x barlow.  You can use the barlow with your Morpheus to get ~190x magnification for high-power views of planets and the moon.  A low power eyepiece is useful for globular clusters, large nebulas, etc.  You can also use the barlow with the low power eyepiece and in essence with 2 eyepieces and a barlow, you will get four different levels of magnification to choose from.

Thank you for the input! The scope comes with a 1.25 25mm Orion Sirius Plossl



#12 Tony Flanders

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Posted 28 October 2020 - 05:36 AM

I have a 10in f/4.7 Dob on the way. So far, I have ordered one eyepiece in anticipation of its arrival. The EP that I have is the Baader 1.25" and 2" Morpheus 76° Wide-Field Eyepiece - 12.5mm.


That's a curious choice; I'm curious about your rationale. In an f/4.7 scope, the 12.5-mm eyepiece delivers an exit pupil of 12.5/4.7 ~= 2.7 mm.

Now it's true that I use all of my eyepieces at some point, but the range with exit pupils between 2 and 4 mm is the one that I use least often.

The exit pupil that I use most is around 1.5 mm, which would be 1.5*4.7 ~= 7 mm in your scope. Not only is that great for deep-sky objects, it's also roughly the highest magnification (in my bigger scopes) that I can use on the planets on nights of average seeing. So if I had been buying just one auxiliary eyepiece for your scope, it would have been a 7 mm.

Now you could achieve that using a 2x Barlow together with your 12.5-mm eyepiece, but it seems a little crazy for your most-used magnification to require a Barlow.

Mind you, everybody likes different magnifications in the same scope; not everybody would find 7 mm their most-used eyepiece. But I think the more experienced users are likely to trend that way.
 
A 7-mm eyepiece plus a 2X Barlow would work well on the planets on those rare nights when the seeing is really good.
 
If I were to get a third eyepiece, besides your stock 25-mm Plossl and a 7-mm, it would be a 2-inch low-power wide-field of some kind.
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#13 Mishulya

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Posted 28 October 2020 - 03:09 PM

That's a curious choice; I'm curious about your rationale. In an f/4.7 scope, the 12.5-mm eyepiece delivers an exit pupil of 12.5/4.7 ~= 2.7 mm.

Now it's true that I use all of my eyepieces at some point, but the range with exit pupils between 2 and 4 mm is the one that I use least often.

The exit pupil that I use most is around 1.5 mm, which would be 1.5*4.7 ~= 7 mm in your scope. Not only is that great for deep-sky objects, it's also roughly the highest magnification (in my bigger scopes) that I can use on the planets on nights of average seeing. So if I had been buying just one auxiliary eyepiece for your scope, it would have been a 7 mm.

Now you could achieve that using a 2x Barlow together with your 12.5-mm eyepiece, but it seems a little crazy for your most-used magnification to require a Barlow.

Mind you, everybody likes different magnifications in the same scope; not everybody would find 7 mm their most-used eyepiece. But I think the more experienced users are likely to trend that way.
 
A 7-mm eyepiece plus a 2X Barlow would work well on the planets on those rare nights when the seeing is really good.
 
If I were to get a third eyepiece, besides your stock 25-mm Plossl and a 7-mm, it would be a 2-inch low-power wide-field of some kind.

That choice was based on a comment from a user on this forum, and my inexperience with eyepieces. I hope I won't regret my purchase! As I mentioned, I am new to the hobby and have just been looking for guidance from those with a scope similar to mine. Thanks for the comment.



#14 SteveG

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Posted 30 October 2020 - 05:39 PM

Thanks, Josh! I do have a 2" 12.5mm EP, it just arrived yesterday! Still waiting on the scope, though...

Those have combo 2"/1.25" barrels. You will want to use them in the 1.25" mode. Get a 1.25" 2x barlow for your 12.5 Morpheus and you'll have a nice planetary eyepiece.

 

The real benefit of a 2" eyepiece is with low-power, widefield views, that cannot be produced by a 1.25" eyepiece. Something like the 2" APM 30 mm UFF eyepiece would be awesome for cruising star fields in the Milky Way. It's also a great "finder" eyepiece.



#15 spaceoddity

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Posted 30 October 2020 - 08:12 PM

Since my scopes have 2" focusers, I never remove the 2" skirts from 1.25" eyepieces that have them.  



#16 Mishulya

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Posted 31 October 2020 - 10:44 PM

Those have combo 2"/1.25" barrels. You will want to use them in the 1.25" mode. Get a 1.25" 2x barlow for your 12.5 Morpheus and you'll have a nice planetary eyepiece.

 

The real benefit of a 2" eyepiece is with low-power, widefield views, that cannot be produced by a 1.25" eyepiece. Something like the 2" APM 30 mm UFF eyepiece would be awesome for cruising star fields in the Milky Way. It's also a great "finder" eyepiece.

Appreciate this, Steve! I have been on the search for a good 2x barlow, but literally everything is backordered right now! Maybe because of people like myself getting into the hobby during the pandemic grin.gif



#17 Mishulya

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Posted 31 October 2020 - 10:46 PM

Since my scopes have 2" focusers, I never remove the 2" skirts from 1.25" eyepieces that have them.  

Hi, really dig your name - big Bowie fan.



#18 wrvond

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Posted 01 November 2020 - 01:43 PM

To be clear, any eyepiece that is 1.25" and 2" cannot be classed as a 2" ocular. The 2" skirt is simply there for convenience to allow folks using 2" EPs to avoid having to insert a 2" to 1.25" adapter. Once your scope arrives, you will have two eyepieces, if you leave the skirt on the Morpheus you'll have to insert and remove the focuser adapter every time you want to switch views. Much easier to remove the skirt from the Morpheus and stick with the 1.25" form factor.

I enjoyed amazing views of DSO's for many years through a 32mm Plossl on my reflector before purchasing a 2" EP. They are fantastic for sure, but not absolutely necessary to enjoy the night sky.

If you go to https://astronomy.to.../field_of_view/ you can plug in your scope and any eyepiece you are interested in. The tool will show you a representation of what you can expect to see with that combination.



#19 SteveG

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Posted 01 November 2020 - 01:57 PM

To be clear, any eyepiece that is 1.25" and 2" cannot be classed as a 2" ocular. The 2" skirt is simply there for convenience to allow folks using 2" EPs to avoid having to insert a 2" to 1.25" adapter. Once your scope arrives, you will have two eyepieces, if you leave the skirt on the Morpheus you'll have to insert and remove the focuser adapter every time you want to switch views. Much easier to remove the skirt from the Morpheus and stick with the 1.25" form factor.

I enjoyed amazing views of DSO's for many years through a 32mm Plossl on my reflector before purchasing a 2" EP. They are fantastic for sure, but not absolutely necessary to enjoy the night sky.

If you go to https://astronomy.to.../field_of_view/ you can plug in your scope and any eyepiece you are interested in. The tool will show you a representation of what you can expect to see with that combination.

That's not how the Morpheus works. The "skirt" is not removeable. Most typical situation is you start with your 2", low-power eyepieces, then insert the adaptor for the 1.25" higher power eyepieces, which for most of us is everything below 18-20 mm.

 

The problem I find when using the Morpheus 2" barrel is that when changing between eyepieces it requires a huge amount of refocusing. My suggestion is to use all of your dual-barrel eyepieces in their 1.25" mode, and get a twist-lock 1.25" to 2" adaptor. YMMV


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#20 Mishulya

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Posted 08 November 2020 - 08:21 PM

That's not how the Morpheus works. The "skirt" is not removeable. Most typical situation is you start with your 2", low-power eyepieces, then insert the adaptor for the 1.25" higher power eyepieces, which for most of us is everything below 18-20 mm.

 

The problem I find when using the Morpheus 2" barrel is that when changing between eyepieces it requires a huge amount of refocusing. My suggestion is to use all of your dual-barrel eyepieces in their 1.25" mode, and get a twist-lock 1.25" to 2" adaptor. YMMV

Noted, thanks Steve!



#21 river-z

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Posted 08 November 2020 - 09:31 PM

Like Tony, I also find that my most used eyepiece is the 7mm in my 12" Dob.  

I like it when I can use the 5mm, but the seeing conditions don't always allow for it.   



#22 phillip

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Posted 11 November 2020 - 05:27 AM

All well Covered! Just verify on my XT10 10 inch dob, 7mm is the usual winner for night sky. Things start to improve, quite often moves to 200x 6mm view. Tho not frequent does push to 300x but certainly not often, always glad I have it! 

 

Most pristine sky extremely rare as encountered only 3 in my decades of Viewing is the real Steady Sky. I successfully used with XT8 over 400x with a 4.8 Nagler barlowed in a group viewing of Mars, and as many there to share, most amazing happening for me, sadly it hardly ever happens, Amazing! Hope everyone experiences it at least Once!

 

Clear Sky

Cloudy again AM here, promising tho Tonite! 



#23 epee

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Posted 11 November 2020 - 09:58 AM

On typical nights my 12" tops out with a 6.5mm Morpheus

#24 Waynosworld

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Posted 14 November 2020 - 02:30 AM

Hi there Mishulya, I have a 14.5" F4.5 Starsplitter that has a 2" focus mechanism, I bought a Meade series 4000 14mm ultra wide angle (1.25"/2"OD) eyepiece, I bought a Explore Scientific 2" barlow that came with an adapter, when I received the barlow I looked at everything pretty close, when I carefully slid the dual use 14mm Meade eyepiece in the 2" barlow and the 1.25" part of the 14mm eyepiece hit the barlow lens itself, it hit the actual glass, I was lucky because I did not just shove it home into the barlow with any force.

 

What I learned from this is that the Meade 1.25"/2" eyepiece is really just a 1.25" eyepiece with a 2" adapter, real 2" eyepieces will not have an adapter, so basically what I am saying is if it has the 1.25" part and you want to use a 2" barlow use the adapter that came with it, do not shove that 1.25"/2" eyepiece into that 2" barlow hole, I never actually looked thru that combo to see if it would actually work, I mentioned it in my thread and I was told to not remove the 1.25" piece from the Meade eyepiece as it has a lens in it, use the 1.25" adapter that cam with the 2" barlow.

 

This said I had actually ordered a 1.25" Meade Ultra Wide Angle 6.7mm eyepiece, what a great eyepiece it is, I have that 14mm Meade, and when I put it in the 2" barlow 2X with the adapter I basically have a 7mm eyepiece, but it has a barlow lens, so my telescope needs to be collimated for the use of a barlow lens, plus both them pieces of equipment together weigh a lot, I have to add weights to my telescope to keep it balanced, well I chose to use the 2" to 1.25" adapter and 6.7mm eyepiece every time, I have not used the 14mm Meade/ES barlow since. I have over $500.00 into the two pieces and I have less than a $150.00 into the Meade 6.7mm UWA eyepiece, I have been looking for a 9mm or 10mm Meade UWA eyepiece since.

001.JPG

 

Now I am a resourceful guy, look at the photos below, I figured out that this 1.25" barlow(2X) I bought 3 or 4 months ago had a removable barlow lens, if I removed it from the barlow housing and put it on my Meade UWA 6.7mm eyepiece it turned it into something close to a 5mm eyepiece(See photo below), and that was just perfect for that day, I had tried the 2" ES 2X barlow and the 6.7mm eyepiece and it was too much magnification, the black section on the eyepiece in the photo belongs on the short barlow housing piece above it.

003.JPG

 

I have concluded when I want to look at DSOs I will buy a real 2" only eyepiece with a UWA so I can see everything, until then I will likely use the 2" Meade 14mm eyepiece without the barlow, I really didn't need to spend the money on that barlow, but I suspect at some point I will use it, right now I am trying to focus on the planets and get used to my giant to me telescope, learn how to use it and keep it in tip top shape, the more I read of others threads the more I will want to start looking at DSOs when there are no planets to look at and the conditions are not good for planets anyway, I found a hand book about astronomy a couple days ago on a shelf that the guy I bought the house from must of left here, it has sky charts for every month of the year and where everything is, that got me thinking..................

 

 

By the way, I am a newbie, I just post a lot.


Edited by Waynosworld, 14 November 2020 - 02:44 AM.


#25 Waynosworld

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Posted 14 November 2020 - 02:42 AM

Here is what the barlow and eyepiece are supposed to look like.

004.JPG

 

And here is when I removed the end off the barlow and put it on the Meade 6.7mm eyepiece.

003.JPG

 

I expect my telescope would need to be collimated for it to be used this way also, but it worked fine that night I was looking at Mars, I actually could clearly see details, enough to describe them and have someone tell me I was at about 300X and I was describing the details accurately.


Edited by Waynosworld, 14 November 2020 - 02:43 AM.



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