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After a few years with Morpheus eyepieces

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738 replies to this topic

#51 vrodriguez2324

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Posted 23 April 2024 - 09:01 PM

The 3800 case is indeed a good match for the Morpheus series. No 4.5mm or 14mm in the collection, but a VIP Barlow and 30mm UFF. This arrangement covers everything I need.

 

attachicon.gif CN EP Case with DYI Trek Pak.jpg

Nice job! I like your All-In-Wonder setup. Filters for Luna, the planets, and nebulae. Premium quality eyepieces that can be used by all observers. The range of focal lengths covers all the bases and is easily expanded by using the Barlow. Laser and Farpoint Chesire to dial in the alignment of your optics. What else do you really need?

 

May I kindly ask where you sourced your dividers? I have a similar Apache case. The pluck foam is serviceable but definitely the weakest link. 

 

-Victor

 

If you are a "Inside Track Member" you get an additional 25% off the XL version. 

https://www.harborfr...reen-56863.html

 

I purchased the membership when I needed a jack for the garage. 


Edited by vrodriguez2324, 23 April 2024 - 09:02 PM.

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#52 Neanderthal

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Posted 23 April 2024 - 10:12 PM

The dividers are "Trekpak" style. Here's a good video tutorial:

https://www.youtube....RD1t6arwoGWra6l

 

I used 4mm neoprene on each side of the 1/4" Coroplast board. Some folks use bobby pins to hold the panels together, I went ahead and bit the bullet for the real Trekpack pins, which cost as much or more than the rest of the material combined, lol. The system works really well, happy with it. smile.gif


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#53 Dave Mitsky

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Posted 24 April 2024 - 12:44 AM

I would happily acquire two or three more Morpheus eyepieces in shorter focal lengths than the 17.5 and 12.5mm versions that I own but I already have so many fine eyepieces in that range.   


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#54 niki3

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Posted 24 April 2024 - 07:00 AM

 

- The 17.5mm - 14mm - 12.5 mm spacing is less than ideal.  I think as a set, the 17.5-12.5-9-6.5-4.5 very workable, the 14mm is the odd man out.  Add a 2 inch like the 30mm UFF or the 28mm UWA and maybe a 2x Barlow for the high magnifications and you are set.. The 30mm UFF seems like a good fit, as many have suggested, with it's long eye relief, it fits nicely and deserves the title of as an honorary Morpheus. 

 

What telescope did you look through?



#55 zman2100

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Posted 24 April 2024 - 09:57 AM

The 3800 case is indeed a good match for the Morpheus series. No 4.5mm or 14mm in the collection, but a VIP Barlow and 30mm UFF. This arrangement covers everything I need.

 

attachicon.gif CN EP Case with DYI Trek Pak.jpg

This is art.


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#56 25585

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Posted 24 April 2024 - 10:40 AM

I would happily acquire two or three more Morpheus eyepieces in shorter focal lengths than the 17.5 and 12.5mm versions that I own but I already have so many fine eyepieces in that range.   

I had and have others. I like trying new chocolates eyepieces, and when starting with Morpheus, I realised just how right they are for me. There are only 4 whole ranges that I use; Vixen LVs, Vixen LVWs, Baader Morpheus and ES92s. They all have long enough eye relief for wearing glasses, easy enough eye placement, and excellent optics. 



#57 Jon Isaacs

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Posted 25 April 2024 - 10:06 AM

What telescope did you look through?

Quite a variety.

 

90 mm F/6.2 apo, TV NP-101, 10 inch F/5 Dob, 16 inch F/4.4 Dob and 22 inch F/4.4 Dob, Dob's with  Paracorr 2.

 

I'm still getting used to these eyepieces, they Morpheī were a gift and I have too many sets of eyepieces that are very good..

 

Jon



#58 niki3

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Posted 25 April 2024 - 10:16 AM

 

- The 17.5mm - 14mm - 12.5 mm spacing is less than ideal.  I think as a set, the 17.5-12.5-9-6.5-4.5 very workable, the 14mm is the odd man out.  

 

I'm trying to understand why the 14mm isn't needed. It occurred to me that you might have a significantly different telescope from mine - a 305mm F/5. However, you have quite a variety of telescopes, and I don't see a pattern.

 

For a long time, I had 30mm, 18mm, and 11mm eyepieces. I hardly used the 18mm.

Then 24mm, 18mm, 14mm, and 10mm. I still don't use the 18mm, but I use the 14mm for diffuse clusters and to see the Moon in its entirety.


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#59 HellsKitchen

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Posted 25 April 2024 - 10:39 AM

I'm trying to understand why the 14mm isn't needed. It occurred to me that you might have a significantly different telescope from mine - a 305mm F/5. However, you have quite a variety of telescopes, and I don't see a pattern.

 

For a long time, I had 30mm, 18mm, and 11mm eyepieces. I hardly used the 18mm.

Then 24mm, 18mm, 14mm, and 10mm. I still don't use the 18mm, but I use the 14mm for diffuse clusters and to see the Moon in its entirety.

 

 

In the Morpeheus line up, the 14mm is too close to either the 12.5mm and 17.5mm. A more natural progression in the set eliminates the 14mm.


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#60 Starman1

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Posted 25 April 2024 - 11:16 AM

I think, in the original design, that 14mm was the longest focal length possible with the design, which is why there is a 14mm.

The 17.5mm was released over 3 years later, and went through at lest 3 prototypes before they got it right.

Even then, the final version has less apparent field than the others (72.2° versus 78.3-79°), a much longer eye relief,

and a visible difference in correction.

Once the 17.5mm came out, though, it was easy to see what Baader had in mind for the magnification progression.

Like the 1.25" Pentax XW, they follow a 40% change between focal lengths, but only if you exclude the 14mm.

Perhaps for this reason, the 14mm became the least popular focal length.

 

Ernest Maratovich's lab tests showed the 17.5mm to be superior to the 14mm, but I see the reverse.

I can't account for that.  Is it individual eyepiece variation, or something about my eye at that exit pupil, or some other issue?  I don't know.

I do have longer focal length eyepieces that are sharper than the 17.5mm, so I don't think it's the correction in my glasses.

 

Also, I have adjusted the eyeguard positions on all the Morpheus so they are identical to my glasses.

I inserted thin o-rings under the eyeguards on a few of them to get the eye relief to exactly the point where, when my glasses touch the tops all the way around the rubber, I *just* see the field stops.

This eliminates any personal feelings about eye relief in evaluating the individual focal lengths.

I recently did this after some other posters' comments, and it made a difference the first night I used these on the Moon.

 

As has been reported, if you hold your eye the wrong distance away from the eyepiece, there is some chromatic aberration of the exit pupil that yields a brownish tint to the very outer field.

I see this in the Pentax XWs when used in daylight, except there the coloration is yellow.

Using those thin o-rings has allowed me to optimize each focal length for my glasses, and now I do not experience the edge coloration when viewing the Moon.

 

I mention this because they are very capable Moon viewing eyepieces if you manage to optimize your eye position relative to the lens.

As they come out of the box, you have at least 4 different positions for the eyeguard, not to mention the eyeguard can be unscrewed a MM or two, resulting in a huge range of adjustment.

I think it's worth the experimentation, because it makes the focal lengths more uniform and comfortable to use.


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#61 rgk901

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Posted 25 April 2024 - 11:37 AM

was just using the 17.5 for a quick look at the moon last night..and just thought to myself that although this one has the narrowest FOV it actually did not feel that way in the eyepiece... seemed just as expansive as the others even of it does really show less true field.
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#62 25585

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Posted 25 April 2024 - 12:33 PM

I'm trying to understand why the 14mm isn't needed. It occurred to me that you might have a significantly different telescope from mine - a 305mm F/5. However, you have quite a variety of telescopes, and I don't see a pattern.

 

For a long time, I had 30mm, 18mm, and 11mm eyepieces. I hardly used the 18mm.

Then 24mm, 18mm, 14mm, and 10mm. I still don't use the 18mm, but I use the 14mm for diffuse clusters and to see the Moon in its entirety.

In the Morpheus range, 14mm is the longest FL parfocal with shorter FLs. Outside Moirpheus i.e. generally, I use 14mm when 12mm can be unsuitable if too high powered or too small an exit pupil. Eyepieces can be like sockets in a socket wrench set, that fraction of difference can be useful. 
 

In long FL telescopes such as Cassegrains, a 14mm might be the one better suited to useful magnification, or if in a Newtonian with a Paracorr and therefore slightly boosted FL, a 14mm might be better than a 13mm or shorter. My 12.5 and 14mm Morpheus are the two most swapped around.


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#63 vrodriguez2324

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Posted 25 April 2024 - 01:01 PM

I'm trying to understand why the 14mm isn't needed. It occurred to me that you might have a significantly different telescope from mine - a 305mm F/5. However, you have quite a variety of telescopes, and I don't see a pattern.

 

For a long time, I had 30mm, 18mm, and 11mm eyepieces. I hardly used the 18mm.

Then 24mm, 18mm, 14mm, and 10mm. I still don't use the 18mm, but I use the 14mm for diffuse clusters and to see the Moon in its entirety.

I skipped over the 14 initially also because, as many have said, it is too close to the 12.5 and 17.5. But also the Morpheus have to play well with the longer focal length eyepieces in your kit. I found the 17.5 too close to my 22NT4 which I really like and often just skipped over the 17.5 and used the 12.5. I would also find myself skipping the 9 because it wasn't different enough from 12.5 and would reach for the 6.5. 

 

This also depends on your telescope. I use a 200mm f/5 (Coma corrected to f/5.75) reflector. The 22-14-9-6.5 range is perfect for me providing magnifications of 52x-82x-128x-177x and simplifies my observing. The jump from the 14 to the 9 is a difference of 45x, just right. The 12.5 was too close to the 9. 

 

I have a 5mm Pentax for 230x which is another jump of about 50x from the 6.5. Swapping out the 17.5 and the 12.5 for the 14 got me the "perfect magnification spacings" of 50x from the 14 on down. 

 

This is scope dependent of course and can see that the 17.5-12.5-9-6.5 can work better in instruments with longer focal lengths. 


Edited by vrodriguez2324, 25 April 2024 - 02:00 PM.

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#64 mountain monk

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Posted 25 April 2024 - 01:51 PM

Don,

 

What size o-rings did you use on the Morpheus?

 

Dark skies.

 

Jack



#65 Jon Isaacs

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Posted 25 April 2024 - 02:12 PM

I'm trying to understand why the 14mm isn't needed. It occurred to me that you might have a significantly different telescope from mine - a 305mm F/5. However, you have quite a variety of telescopes, and I don't see a pattern.

 

For a long time, I had 30mm, 18mm, and 11mm eyepieces. I hardly used the 18mm.

Then 24mm, 18mm, 14mm, and 10mm. I still don't use the 18mm, but I use the 14mm for diffuse clusters and to see the Moon in its entirety.

 

You've gotten some good answers.  As I said, I'm still becoming accustomed to the Morpheī.  

 

I like sets of eyepieces that are consistent both physically and optically with reasonably uniform step sizes. 

 

Optimal is a ~ 30 mm Wide Field as an anchor and then a smooth progression. This is pretty good.

 

1.25 inch = 22mm Panoptic, 16 mm Type 5, 13 mm, 11 mm , 9 mm, 7 mm, 5 mm, 3.5 mm Type 6.

 

2 inch 100°  = 20 mm , 13 mm, 10 mm, 8 mm, 6 mm, 4.8 mm 3.5 mm.  I'm still working on this. I have a mixed set of Ethos and XWAs, plus a 2 x Barlow. 

 

What I actually have is 20 mm, 13.5 mm, 13 mm, 10 mm, 9 mm, 8 mm, 7 mm, 4.8 mm, 3.5 mm. 

 

The Morpheī are just a bit goofy. The steps are wider than I like but I'm trying to adjust. The 17.5 mm - 14 mm 12.5 mm -9mm is herky-jerky. 17.5 mm-14 mm - 11 mm - 9 mm would be better. 

 

But 30 mm -17.5  12.5 mm -9 mm -6.5 mm -4.5 mm is a nice bit slightly wide spacing.

 

Jon


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#66 Starman1

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Posted 25 April 2024 - 02:38 PM

Don,

 

What size o-rings did you use on the Morpheus?

 

Dark skies.

 

Jack

1-5/8" of 0.07" diameter, with round cross-section.

2 eyepieces needed just one, while one eyepiece needed 2.

I did not tighten the eyeguard enough to squash the o-rings but just enough that there was friction in unscrewing the eyeguards.

That way, I knew they would stay in place and I figured the o-rings would last longer.

Since the top of the Morpheus eyepieces, Pentax XWs and APM Hi-FW are all 43mm under the eyeguard, I could see that such spacers would be useful on more than just the Morpheus eyepieces.

And if you use the eyeguard extenders on the Morpheus EPs, the o-ring could mount between the eyeguard and the extender as well as under both.


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#67 Starman1

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Posted 25 April 2024 - 03:03 PM

It is interesting to note that if all your eyepieces have the same apparent field, a 1.414x step in magnifications between eyepieces results in each successively shorter eyepiece focal length having exactly 50% the field area

of the previous, larger, focal length.  I think this may possibly be where the 40% change in focal lengths came from.

Take the Pentax XWs:

3.5 x 1.4 = 5 x 1.4 = 7 x 1.4 = 10 x 1.4 = 14 x 1.4 = 20

Take the Morpheus as labeled:

4.5 x 1.4 = 6.5 x 1.4 = 9 x 1.4 = 12.5 x 1.4 = 17.5

 

If you prefer a constant magnification change between eyepieces, then high power eyepieces will be closer together.

For example, if you wanted a 50x progression with an 8" scope with a 1200mm focal length, a 40% jump between eyepieces wouldn't work.

Instead, you'd have a 24mm, 12mm, 8mm, 6mm, 4.8mm, 4mm sequence, for differences of 50%, 33.3%, 25%, 20%, and 16.7%

 

No eyepiece grouping really perfectly fits a particular scope, though we definitely do get used to certain sequences.

My ideal eyepiece is a 10mm.  I have an 11mm and a 9mm.  I use the 11mm a lot, but I wish it was a 10mm.

The difference between 11mm and 10mm in my scope is only 17x, but I wish I had the extra 17x quite often.

The 9mm is only a step up from the 11 of 37x, which is pretty close, so if I had a 10mm, the 9mm would be too close.

There is no perfect sequence , so we mix and match.

Years ago, I thought I might be fine with a 14mm>>9mm split, but the difference of 73x was too wide a gap for my preferences.

Splitting in 2 would be fine, but that is an 11mm eyepiece.  Today, I have a 14mm, 11mm, and 9mm, and I often progress that way.

So why do I have a 12.5mm to mess up the progression?  I don't know.  Like cats, eyepieces just happen.lol.gif

I should have a license plate that says: EP LOVER


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#68 CrazyPanda

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Posted 25 April 2024 - 03:08 PM

In the Morpeheus line up, the 14mm is too close to either the 12.5mm and 17.5mm. A more natural progression in the set eliminates the 14mm.

But different people have different scopes.

 

14mm is ideal in an F/7 refractor fro general purpose DSO observing. In that setup, the 12.5 is the odd one out.

 

In an 8" F/6 reflector, the 12.5 is ideal, and the 14 is the odd one out.

 

I like it when eyepiece lines have a variety of options to suit different telescopes even if they seem too close together in sequence.

 

But even in my main scope, I still have 21, 14, 12.5, 10, 9, 8, 7, 6, 4.7, and 3.7. For a while I even had a 17mm in between.

 

Different magnifications and exit pupils for different targets even if the spacing seems really close.
 


Edited by CrazyPanda, 25 April 2024 - 03:09 PM.

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#69 Olimad

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Posted 25 April 2024 - 03:14 PM

It is interesting to note that if all your eyepieces have the same apparent field, a 1.414x step in magnifications between eyepieces results in each successively shorter eyepiece focal length having exactly 50% the field area

of the previous, larger, focal length.  I think this may possibly be where the 40% change in focal lengths came from.

Take the Pentax XWs:

3.5 x 1.4 = 5 x 1.4 = 7 x 1.4 = 10 x 1.4 = 14 x 1.4 = 20

Take the Morpheus as labeled:

4.5 x 1.4 = 6.5 x 1.4 = 9 x 1.4 = 12.5 x 1.4 = 17.5

 

If you prefer a constant magnification change between eyepieces, then high power eyepieces will be closer together.

For example, if you wanted a 50x progression with an 8" scope with a 1200mm focal length, a 40% jump between eyepieces wouldn't work.

Instead, you'd have a 24mm, 12mm, 8mm, 6mm, 4.8mm, 4mm sequence, for differences of 50%, 33.3%, 25%, 20%, and 16.7%

 

No eyepiece grouping really perfectly fits a particular scope, though we definitely do get used to certain sequences.

My ideal eyepiece is a 10mm.  I have an 11mm and a 9mm.  I use the 11mm a lot, but I wish it was a 10mm.

The difference between 11mm and 10mm in my scope is only 17x, but I wish I had the extra 17x quite often.

The 9mm is only a step up from the 11 of 37x, which is pretty close, so if I had a 10mm, the 9mm would be too close.

There is no perfect sequence , so we mix and match.

Years ago, I thought I might be fine with a 14mm>>9mm split, but the difference of 73x was too wide a gap for my preferences.

Splitting in 2 would be fine, but that is an 11mm eyepiece.  Today, I have a 14mm, 11mm, and 9mm, and I often progress that way.

So why do I have a 12.5mm to mess up the progression?  I don't know.  Like cats, eyepieces just happen.lol.gif

I should have a license plate that says: EP LOVER

 

Don, shall we also take into consideration exit pupil? 

Because, depending of F/R, the exit pupil decrease will be different for scopes with same focal length but with different apertures (thus F/R). 


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#70 Starman1

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Posted 25 April 2024 - 03:51 PM

Don, shall we also take into consideration exit pupil? 

Because, depending of F/R, the exit pupil decrease will be different for scopes with same focal length but with different apertures (thus F/R). 

Well, the 1.414 difference in focal length matches the same difference in exit pupil.

If all eyepieces have the same apparent fields, then a 1.414 (41.4%) progression means every higher power would be exactly 50% as bright as the next lower power and have 50% of the field area.

50% is about a half magnitude, which is noticeable but not huge.

So a constant % change would match up well with the same in exit pupils, regardless of the f/ratio of the scope.

 

Whether or not this matches your needs is a different issue.  A lunar/planetary observer might not like the high powers that far apart because of seeing issues.

And a low power, faint nebula, observer might not like the low powers that far apart either because visibility of faint features requires the optimum exit pupil for the observer, especially if a filter is used.

 

Constant magnification change gaps means the change in exit pupil is largest at low powers and smallest at high powers.

But when you observe an object and you feel the need to increase the magnification to see the object better, do you not, if using a low power,

want to increase the power precipitously so there is a quite noticeable difference, regardless of exit pupil change?

And when you are already at high power, don't you run into a "Seeing Ceiling", where the image turns to mush if you jump too much?

 

Yes, the exit pupil choices will result in different focal lengths of eyepieces in scopes of different f/ratios, but a % change will result in the same sequence of exit pupils for scopes of all f/ratios.


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#71 Second Time Around

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Posted 25 April 2024 - 04:29 PM

Well, the 1.414 difference in focal length matches the same difference in exit pupil.

If all eyepieces have the same apparent fields, then a 1.414 (41.4%) progression means every higher power would be exactly 50% as bright as the next lower power and have 50% of the field area.

50% is about a half magnitude, which is noticeable but not huge.

So a constant % change would match up well with the same in exit pupils, regardless of the f/ratio of the scope.

 

Whether or not this matches your needs is a different issue.  A lunar/planetary observer might not like the high powers that far apart because of seeing issues.

And a low power, faint nebula, observer might not like the low powers that far apart either because visibility of faint features requires the optimum exit pupil for the observer, especially if a filter is used.

 

Constant magnification change gaps means the change in exit pupil is largest at low powers and smallest at high powers.

But when you observe an object and you feel the need to increase the magnification to see the object better, do you not, if using a low power,

want to increase the power precipitously so there is a quite noticeable difference, regardless of exit pupil change?

And when you are already at high power, don't you run into a "Seeing Ceiling", where the image turns to mush if you jump too much?

 

Yes, the exit pupil choices will result in different focal lengths of eyepieces in scopes of different f/ratios, but a % change will result in the same sequence of exit pupils for scopes of all f/ratios

As Don says poor seeing means small differences in magnification make a big difference at high powers.  Plus small differences in exit pupil make a big difference with DSOs at lower powers.

 

To get all of these magnifications/exit pupils would require a very large number of eyepieces, and be time consuming to change leading to missing the brief moments of better seeing.  This is one of the many reasons I prefer zooms.


Edited by Second Time Around, 26 April 2024 - 01:15 AM.

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#72 Estel11

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Posted 25 April 2024 - 06:55 PM

I think, in the original design, that 14mm was the longest focal length possible with the design, which is why there is a 14mm.
The 17.5mm was released over 3 years later, and went through at lest 3 prototypes before they got it right.
Even then, the final version has less apparent field than the others (72.2° versus 78.3-79°), a much longer eye relief,
and a visible difference in correction.
Once the 17.5mm came out, though, it was easy to see what Baader had in mind for the magnification progression.
Like the 1.25" Pentax XW, they follow a 40% change between focal lengths, but only if you exclude the 14mm.
Perhaps for this reason, the 14mm became the least popular focal length.

Ernest Maratovich's lab tests showed the 17.5mm to be superior to the 14mm, but I see the reverse.
I can't account for that. Is it individual eyepiece variation, or something about my eye at that exit pupil, or some other issue? I don't know.
I do have longer focal length eyepieces that are sharper than the 17.5mm, so I don't think it's the correction in my glasses.

Also, I have adjusted the eyeguard positions on all the Morpheus so they are identical to my glasses.
I inserted thin o-rings under the eyeguards on a few of them to get the eye relief to exactly the point where, when my glasses touch the tops all the way around the rubber, I *just* see the field stops.
This eliminates any personal feelings about eye relief in evaluating the individual focal lengths.
I recently did this after some other posters' comments, and it made a difference the first night I used these on the Moon.

As has been reported, if you hold your eye the wrong distance away from the eyepiece, there is some chromatic aberration of the exit pupil that yields a brownish tint to the very outer field.
I see this in the Pentax XWs when used in daylight, except there the coloration is yellow.
Using those thin o-rings has allowed me to optimize each focal length for my glasses, and now I do not experience the edge coloration when viewing the Moon.

I mention this because they are very capable Moon viewing eyepieces if you manage to optimize your eye position relative to the lens.
As they come out of the box, you have at least 4 different positions for the eyeguard, not to mention the eyeguard can be unscrewed a MM or two, resulting in a huge range of adjustment.
I think it's worth the experimentation, because it makes the focal lengths more uniform and comfortable to use.

I am also noticing that the 14mm seems a bit brighter. Viewing with a 125mm refractor, M42 is very bright and detailed with the 14mm. I prefer the view with that eyepiece to the 12.5mm version. That seem a bit odd to me- there's not much difference in magnification. I really should sell the 14 based on practicality, but I'm going to hold off on that. I like all of them, 17.5 to 9, and the 14 is supposed to be the "weak link" in the series- but so far I don't see that at all. I really am impressed with the views.
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#73 Jon Isaacs

Jon Isaacs

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Posted 25 April 2024 - 08:10 PM

 

My ideal eyepiece is a 10mm. I have an 11mm and a 9mm. I use the 11mm a lot, but I wish it was a 10mm.

 

I spend a lot of money in an effort to avoid buying the 10 mm Ethos. I bought the Baader 8-24 zoom, the 11 mm and 13mm Type 6 Naglers tying to avoid buying that 10 mm Ethos to fill the gap between the 13 mm and 8 mm Ethos.

 

Then serendipity smiled and Jon spotted a 10 mm Ethos on CN for $350 shipped. I wasted two years tying to save $100.

 

Jon


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#74 Andrea Salati

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Posted 25 April 2024 - 08:52 PM

I spend a lot of money in an effort to avoid buying the 10 mm Ethos. I bought the Baader 8-24 zoom, the 11 mm and 13mm Type 6 Naglers tying to avoid buying that 10 mm Ethos to fill the gap between the 13 mm and 8 mm Ethos.

 

Then serendipity smiled and Jon spotted a 10 mm Ethos on CN for $350 shipped. I wasted two years tying to save $100.

 

Jon

I just ended a similar odyssey that involved a Delos 14.


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#75 HellsKitchen

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Posted 26 April 2024 - 03:33 AM

You've gotten some good answers.  As I said, I'm still becoming accustomed to the Morpheī.  

 

I like sets of eyepieces that are consistent both physically and optically with reasonably uniform step sizes. 

 

Optimal is a ~ 30 mm Wide Field as an anchor and then a smooth progression. This is pretty good.

 

1.25 inch = 22mm Panoptic, 16 mm Type 5, 13 mm, 11 mm , 9 mm, 7 mm, 5 mm, 3.5 mm Type 6.

 

2 inch 100°  = 20 mm , 13 mm, 10 mm, 8 mm, 6 mm, 4.8 mm 3.5 mm.  I'm still working on this. I have a mixed set of Ethos and XWAs, plus a 2 x Barlow. 

 

What I actually have is 20 mm, 13.5 mm, 13 mm, 10 mm, 9 mm, 8 mm, 7 mm, 4.8 mm, 3.5 mm. 

 

The Morpheī are just a bit goofy. The steps are wider than I like but I'm trying to adjust. The 17.5 mm - 14 mm 12.5 mm -9mm is herky-jerky. 17.5 mm-14 mm - 11 mm - 9 mm would be better. 

 

But 30 mm -17.5  12.5 mm -9 mm -6.5 mm -4.5 mm is a nice bit slightly wide spacing.

 

Jon

 

 

My proposed set, using my 8", 1200mm FL dob, will result in the following magnfications

 

Delos 3.5 ............................. 343x

Morpheus 4.5(4.8) ............... 250x

Morpheus 6.5(6.7) ............... 179x

Morpheus 9(8.9) .................. 135x

Morpheus 12.5(12.4) ............ 97x

Morpheus 17.5(17.2) ............ 70x

Nagler 26T5 ......................... 46x

 

 

Most obvious gaps here are 179-250-343x. I'll probably use this mostly for deep sky, my reasoning is that one doesn't need to fine tune for seeing as much for DSOs as for planetary/lunar.  Instead here it's more according to the type/size/brightness of the DSO.

 

The 2.5x Powermate will add 448, 625, 857x for those small high sfc brightness PNe in good seeing. I have a 5x PM aswell, but that essentially duplicates with 484-674-896x.  A 3x Barlow would actually sensibly fill a lot of these gaps.... and then it's back to square one - barlow juggling crazy.gif


Edited by HellsKitchen, 26 April 2024 - 03:39 AM.

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