95 replies to this topic

[Dr Arnheim]

Well, the Morpheus 4.5mm (actually 4.8mm) is an unusually sharp eyepiece (very small spot size), from edge to edge,

while the 3.5mm XWA is only that sharp in the center 1/3 of the field.  In a binoviewer, that's about the amount of field you use anyway.

Were you to compare them with Cyclops use, you'd rate the outer 50% of the field a lot better in the Morpheus.

 

Ernest's tests of the series shows the 3.5mm the least sharp of all the XWA focal lengths.

Thank you Don. I still like the XWA a lot; I can merge the images even better in my binoviewer and double telescope with them than with the Morpheus and they really give me the feeling to float in space. Now I just found out that I have to keep the Morpheus.

And did I mention that Baader should come up with a Morpheus 3.5mm or 3mm? 

[25585]

Thank you Don. I still like the XWA a lot; I can merge the images even better in my binoviewer and double telescope with them than with the Morpheus and they really give me the feeling to float in space. Now I just found out that I have to keep the Morpheus.

And did I mention that Baader should come up with a Morpheus 3.5mm or 3mm? 

Barlow the 6.5mm.

[Starman1]

Thank you Don. I still like the XWA a lot; I can merge the images even better in my binoviewer and double telescope with them than with the Morpheus and they really give me the feeling to float in space. Now I just found out that I have to keep the Morpheus.

And did I mention that Baader should come up with a Morpheus 3.5mm or 3mm? 

Eyepieces shorter than 4.5-5mm are VERY slow sellers.  It's unlikely that there will be a shorter Morpheus.

Get a really good Barlow and use it on the 6.5mm (6.7mm) Morpheus to yield a 3.35mm focal length.

There are some VERY good 2X Barlows out there.

Since you use a binoviewer, there may be several different magnifications of Glass Path Corrector that would work well, though a decent Barlow might work.

Due to the long light path in binoviewers, it would need to be a telecentric Barlow, like those from Tele Vue (PowerMate), Explore Scientific (Focal Extender), Astrotech Telecentric, or Harry Siebert (telecentric).

That way the magnification will be the same if you use the Barlow under the Binoviewers.

[Dr Arnheim]

Eyepieces shorter than 4.5-5mm are VERY slow sellers.  It's unlikely that there will be a shorter Morpheus.

Get a really good Barlow and use it on the 6.5mm (6.7mm) Morpheus to yield a 3.35mm focal length.

There are some VERY good 2X Barlows out there.

Since you use a binoviewer, there may be several different magnifications of Glass Path Corrector that would work well, though a decent Barlow might work.

Due to the long light path in binoviewers, it would need to be a telecentric Barlow, like those from Tele Vue (PowerMate), Explore Scientific (Focal Extender), Astrotech Telecentric, or Harry Siebert (telecentric).

That way the magnification will be the same if you use the Barlow under the Binoviewers.

 

Barlow the 6.5mm.

I actually don't have a problem with the binoviewer getting higher magnifications but only with my double refractor. The double refractor doesn't have enough infocus travel to use a normal barlow (I tried a Baader Vip). My research lead me also to Tele Vue PowerMates and to the telecentric barlows (Ad 3) from Harry Siebert. Do I understand it right that these Barlows don't change eye relief as well as focus travel?

I could also buy the Star Splitter 4 eyepieces from Harry Siebert (available in 2.4mm, 2.7mm and 2.9mm all 68 degree view field). 

 

Happy to hear your opinion if you would rather go with a telecentric barlow + Morpheus or the Star Splitters.

 

PS, The Astro-Tech seems to be a very good choice as well. I did some research here and only read positive opinions (one even preferred it to his PowerMates). For 60 USD the price is also unbeatable. 

Edited by Dr Arnheim, 20 March 2025 - 11:00 AM.

[Starman1]

I actually don't have a problem with the binoviewer getting higher magnifications but only with my double refractor. The double refractor doesn't have enough infocus travel to use a normal barlow (I tried a Baader Vip). My research lead me also to Tele Vue PowerMates and to the telecentric barlows (Ad 3) from Harry Siebert. Do I understand it right that these Barlows don't change eye relief as well as focus travel?

I could also buy the Star Splitter 4 eyepieces from Harry Siebert (available in 2.4mm, 2.7mm and 2.9mm all 68 degree view field). 

 

Happy to hear your opinion if you would rather go with a telecentric barlow + Morpheus or the Star Splitters.

A telecentric Barlow isn't necessarily parfocal with the eyepieces.  The PowerMate is, the ES FEs are not, for example.

They do not change the eye relief of an eyepiece, nor vignette (typically), though they are not necessarily parfocal with the eyepieces used by themselves.

 

Eyepieces over 70° are kind of tough in binoviewers.  If you attempt to look directly at the right or left edges of the field, it will lift the pupil of one eye away from its exit pupil.

So the peripheral field stays in the periphery of your vision and is not visible with direct vision.

Still, since most people using wider eyepieces do not look at much more than the center 70° with direct vision anyway, ultrawide eyepieces are viable in binoviewers

so long as it is understood the R and L edges of the field will not be viewable with direct, foveal, vision.

 

That being the case, I would recommend the Morpheus eyepieces for several reasons. 

[CosmicWreckingBall]

Dr. Arnheim, 

I'm not sure how much travel you need but I wonder if this might give you that tiny bit?  And I'm not sure how your eyepiece holders work?

https://agenaastro.c...coaAr88EALw_wcB

I thought of it when I read your comment, this was the solution for my TV Bino + Delos EPs back in the day.  On the front of the bino of course (scope facing).

Edited by CosmicWreckingBall, 20 March 2025 - 11:07 AM.

[LDW47]

Dr. Arnheim, 

I'm not sure how much travel you need but I wonder if this might give you that tiny bit?  And I'm not sure how your eyepiece holders work?

https://agenaastro.c...coaAr88EALw_wcB

I thought of it when I read your comment, this was the solution for my TV Bino + Delos EPs back in the day.  On the front of the bino of course (scope facing).

I have / use one for certain circumstances, it works perfectly for next to nothing cost.

[Dr Arnheim]

A telecentric Barlow isn't necessarily parfocal with the eyepieces.  The PowerMate is, the ES FEs are not, for example.

They do not change the eye relief of an eyepiece, nor vignette (typically), though they are not necessarily parfocal with the eyepieces used by themselves.

 

Eyepieces over 70° are kind of tough in binoviewers.  If you attempt to look directly at the right or left edges of the field, it will lift the pupil of one eye away from its exit pupil.

So the peripheral field stays in the periphery of your vision and is not visible with direct vision.

Still, since most people using wider eyepieces do not look at much more than the center 70° with direct vision anyway, ultrawide eyepieces are viable in binoviewers

so long as it is understood the R and L edges of the field will not be viewable with direct, foveal, vision.

 

That being the case, I would recommend the Morpheus eyepieces for several reasons. 

Perfect. I will write Harry as well as Astronomics if their telecentrics are parafocal and will go with one of them instead of the Star Splitters.

 

Btw, of course I know the effect that you describe that you can't see the edge of the field with ultra wide eyepieces in a binoviewer or double telescope but I think it also depends a lot on the eyepiece in use. One thing that I like about the XWA so much is that I can move my eyes more than with other eyepieces when used with both eyes without getting blackouts. And even when I can't see the edge of the field, I really like the immersiveness of wide field eyepieces in binoviewers and double telescopes (which doesn't mean that I can also enjoy Plossls or other narrower eyepieces).

[Dr Arnheim]

Dr. Arnheim, 

I'm not sure how much travel you need but I wonder if this might give you that tiny bit?  And I'm not sure how your eyepiece holders work?

https://agenaastro.c...coaAr88EALw_wcB

I thought of it when I read your comment, this was the solution for my TV Bino + Delos EPs back in the day.  On the front of the bino of course (scope facing).

Oh, this is nice, but doesn't work with my eyepiece holders. There is also not much inward space left since I use EMS modules on my double telescope and have to be careful that the ends of the eyepieces don't touch the mirrors.

[Jon Isaacs]

 

 

However, yesterday I was spending a few hours on double stars and was astonished that I could split double stars equally well with the XWA 3.5mm and the Morpheus 4.5mm, that made me think that the Morpheus are optically better. Is that a fair valuation or could this result due to other factors like f.i. seeing (that means that the seeing was not good enough that the extra magnification would have added resolution)?

Baader should really release a Morpheus 3.5mm or even better 3mm.

 

What scope were you using, what were the doubles and what were the magnifications?

 

I use a 2X 1.25 inch TeleVue Barlow with the Morpheus's. With TeleVue eyepieces, it's parfocal. With the Morpheus's, in my believe it actually requires outward travel but I would want to check.

 

For shorter focal length eyepieces, there's no reason to use a Power mate

 

Jon

[Dr Arnheim]

What scope were you using, what were the doubles and what were the magnifications?

 

I use a 2X 1.25 inch TeleVue Barlow with the Morpheus's. With TeleVue eyepieces, it's parfocal. With the Morpheus's, in my believe it actually requires outward travel but I would want to check.

 

For shorter focal length eyepieces, there's no reason to use a Power mate

 

Jon

I use two Borg 107FL tubes for the double refractor. They have a focal length of 600mm (f/5.6) so I "only" reach 133x with the Morpheus 4.5mm and 171x with the XWA 3.5mm. With the EMS modules merging is no problem at all at this magnification and the Borgs can pull definitely more magnification than 171x.

I've just started to observe double stars the other night and had so much fun for hours. So, I naturally want to see where the limit of my system/eyes is.

Edited by Dr Arnheim, 20 March 2025 - 11:43 AM.

[Jon Isaacs]

I use two Borg 107FL tubes for the double refractor. They have a focal length of 600mm (f/5.6) so I "only" reach 133x with the Morpheus 4.5mm and 171x with the XWA 3.5mm. With the EMS modules merging is no problem at all at this magnification and the Borgs can pull definitely more magnification than 171x.

I just started to observe double stars the other night and had so much fund for hours. So I naturally want to see where the limit of my system/eyes is.

 

How close were the doubles? Names?  Very close doubles require high magnifications but many doubles only require moderate magnifications.  Close for a 4 inch would be 1.5" or under.

 

I use https://www.stelledoppie.it/index2.php as a resource as well as SkySafari Pro.  

 

Jon

[Dr Arnheim]

How close were the doubles? Names?  Very close doubles require high magnifications but many doubles only require moderate magnifications.  Close for a 4 inch would be 1.5" or under.

 

I use https://www.stelledoppie.it/index2.php as a resource as well as SkySafari Pro.  

 

Jon

I was trying the ones from this thread: https://www.cloudyni...northern-hydra/

From which I could only split two (one was Epsilon Hydrae), I was splitting Riegl and tried Sirius but couldn't manage to split it. Then I was using Star Safari to find more double stars. I have to start taking notes to manage to try the same doubles stars under different seeing conditions. I also didn't grasp yet how to calculate what I can split and what not (I only understand so far that the magnitudes of double stars change over time as their distance).

I would have never expected that double stars are so much fun but observing them and then finding the second star (that sometimes has a different color to the bigger one) was quite meditative and double stars are not so much affected from my Bortel 7 sky.

[Starman1]

What scope were you using, what were the doubles and what were the magnifications?

I use a 2X 1.25 inch TeleVue Barlow with the Morpheus's. With TeleVue eyepieces, it's parfocal. With the Morpheus's, in my believe it actually requires outward travel but I would want to check.

For shorter focal length eyepieces, there's no reason to use a Power mate

Jon

The Tele Vue Barlows are parfocal with Tele Vue 1.25" eyepieces because the Barlow's focal plane is 0.25" down inside the barrel and the focal planes of the eyepieces are 0.25" below the shoulders of the eyepieces. 4.5 through 14mm Morpheus eyepieces have their focal planes at the shoulder, so the combination will require 0.25" of in-travel at the focuser in order to extend the scope's focal plane 0.25" farther out--enough to meet the focal planes of the eyepieces. The 17.5mm Morpheus has its focal plane 2.5mm above the sholder, so will require 2.5mm additional in-travel from the other Morpheus focal lengths.

Edited by Starman1, 20 March 2025 - 12:23 PM.

[Jon Isaacs]

The Tele Vue Barlows are parfocal with Tele Vue 1.25" eyepieces because the Barlow's focal plane is 0.25" down inside the barrel and the focal planes of the eyepieces are 0.25" below the shoulders of the eyepieces. 4.5 through 14mm Morpheus eyepieces have their focal planes at the shoulder, so the combination will require 0.25" of in-travel at the focuser in order to extend the scope's focal plane 0.25" farther out--enough to meet the focal planes of the eyepieces. The 17.5mm Morpheus has its focal plane 2.5mm above the sholder, so will require 2.5mm additional in-travel from the other Morpheus focal lengths.

 

Don:

 

I just went outside with the 16mm Type 5 Nagler, my 1.25 inch 2x TeleVue Barlow and the 14mm Morpheus.. I used my 90mm Megrez FD which has a "calibrated" focuser.  I chose a distant tree to focus on.  

 

The numbers based on multiple repetitions :

 

16 mm Nagler:  52.5mm without the Barlow, 52.5 mm with the Barlow

 

14mm Morpheus:  46.5mm without the Barlow, 51.5mm with the Barlow.   The 14mm Morpheus with the Barlow focuses about 5mm outward of where it focuses without the Barlow.  

 

I also tried the 18mm Paradigm, it was essentially parfocal with the 14mm Morpheus both with and without the Barlow.  

 

The 14mm Morpheus with a Celestron GSO Shorty Barlow focuses about 1.5 mm inward, TeleVue 16mm T-5 with the shorty Barlow focuses at 46.5mm, about 6mm inward.

 

I checked closely make sure everything was seated properly, no problems there.

 

The location of the focal plane of a Barlow is not fixed, it depends on the spacing...  I once posted some analysis with a schematic that addressed this issue but I am unable to make sense of it now so I will spare everyone the confusion. 

 

Jon

[Piero DP]

I actually don't find the 3.5mm (or actual 3.6mm) APM XWA that bad compared to the others and certainly more than 1/3 FOV is equally sharp in my 16" f4 + PC2 dob.

Said this, I do trust Ernest data, but I also think that more often than not we assume that a sample is identical to the whole batch. I personally found this not to be necessarily the case with the same eyepiece I bought again. I appreciate others can disagree on my comment.

[Jon Isaacs]

I actually don't find the 3.5mm (or actual 3.6mm) APM XWA that bad compared to the others and certainly more than 1/3 FOV is equally sharp in my 16" f4 + PC2 dob.

Said this, I do trust Ernest data, but I also think that more often than not we assume that a sample is identical to the whole batch. I personally found this not to be necessarily the case with the same eyepiece I bought again. I appreciate others can disagree on my comment.

 

 

When I first purchased my 3.5mm XWA, I was disturbed to find that it was not as well corrected as the others. And while I trust Ernest's data, you never know... 

 

I find the 3.5 mm XWA to be a good performer at F/5.  One thing is that F/5 is not F/4 and some eyepieces are significantly better at F/5 than they are at F/4.  Another issue, this is a 110 degree eyepiece.  It is probably more relevant how it performs 35-40 degrees off-axis  than 50-55 degrees off-axis.  With an 82 degree eyepiece, I can easily watch a close double drift past the field stop.  I don't do that with the 3.5mm XWA.

 

Jon

[Piero DP]

 

When I first purchased my 3.5mm XWA, I was disturbed to find that it was not as well corrected as the others. And while I trust Ernest's data, you never know... 

 

I find the 3.5 mm XWA to be a good performer at F/5.  One thing is that F/5 is not F/4 and some eyepieces are significantly better at F/5 than they are at F/4.  Another issue, this is a 110 degree eyepiece.  It is probably more relevant how it performs 35-40 degrees off-axis  than 50-55 degrees off-axis.  With an 82 degree eyepiece, I can easily watch a close double drift past the field stop.  I don't do that with the 3.5mm XWA.

 

Jon

 

Yep, good points!

 

I also felt a bit uncomfortable when I bought it given the available test data.

 

My main reason behind this purchase is for planetary nebuale with my 16" (518x), so sharpness in the outer field was somewhat less critical. I have to say though that the Eskimo nebula showed a touch more detail in this 3.6mm XWA than in the VIP barlow(7mm XWA), although this could also be due to a slighly mismatch in magnification (the VIP(7) was higher) combined with seeing.
Said this, I've also tried this 3.6mm XWA on the Moon with my 16" on a night of good seeing and the view was pretty spectacular. Regarding stars, it seemed well corrected probably up to 50-60% of the FOV. I've compared this with my VIP(6mm Delos). Obviously the latter delivers a higher magnification, but in terms of FOV, it seemed to me that approx 70deg AFOV of the APM XWA were as equally corrected as the VIP(6mm Delos), with the latter showing a modest improvement in contrast.

 

In conclusion, I am quite happy with this 3.6mm XWA. It is used on a specific class of targets with a specific telescope, but it fulfills that task well to me. The VIP(6mm Delos) shows a touch better contrast, but I would not hunt dim PNs at > 600x using 72 deg AFOV with a dob which tracks manually. Maybe PI-Finder could help here though... food for thoughts!  

[saemark30]

How is the Morpheus constructed? It looks like plastic to me from photos.

[Neanderthal]

How is the Morpheus constructed? It looks like plastic to me from photos.

Aluminum alloy with a hard anodized coating, light yet strong. The rubber grip is secured with adhesive. It's sealed against moisture. Very well constructed with attention to functionality.

[Dr Arnheim]

 

Eyepieces shorter than 4.5-5mm are VERY slow sellers.  It's unlikely that there will be a shorter Morpheus.

Get a really good Barlow and use it on the 6.5mm (6.7mm) Morpheus to yield a 3.35mm focal length.

There are some VERY good 2X Barlows out there.

Since you use a binoviewer, there may be several different magnifications of Glass Path Corrector that would work well, though a decent Barlow might work.

Due to the long light path in binoviewers, it would need to be a telecentric Barlow, like those from Tele Vue (PowerMate), Explore Scientific (Focal Extender), Astrotech Telecentric, or Harry Siebert (telecentric).

That way the magnification will be the same if you use the Barlow under the Binoviewers.

Hello Don,

I was following your advice and bought the Astro Tech 2x Tele Extenders. I could only test them today in daylight but I'm quite happy with them so far. See more here for anyone interested in my first impressions.
So just wanted to say thank you   since I would have never thought that a 60 USD tele extender could be this good.

 

Arnheim