Louis D

6 hours ago, vagk said:

I think the most immersive is ES 12mm 92°.

Does it performs well ?

 

Yes.  It is just about perfectly flat of field and astigmatism free edge to edge.  It's also easy to take in and hold the view with eyeglasses.  However, it is massively heavier and larger than the other contenders listed as well as being 2"-only.

2 hours ago, swsantos said:

Not sure if you have seen a Morpheus live but I was also put off by the cartoonish font and its general appearance but ordered a pair anyway for my Maxbright II binoviewer. In person they are cool looking and not at all cartoonish or low rent. The optics were so good I have since gotten two more pairs.

 

Steve

I have the 9mm and 14mm, and the overall design is fine.  I just find the font and color ridiculous.

Compare my 14mm Morpheus in the middle to a couple of actual cartoon font samples:

OR

Admittedly, the Morpheus font is nice and even with no slanting, but it just doesn't look understated or matter of fact like most eyepiece lettering.  It sort of screams "Look at me!!!".

Got mine a few days ago.  It was literally shipped from China to the seller who then slapped a USPS label over the Chinese one.  Regardless, all of the M48 rings appear to be of excellent quality.  Now I can fine tune my CC and field flattener spacings.

4 minutes ago, Don Pensack said:

By the way, the In-Travel adapter of TeleVue does not make the 14mm Delos parfocal with other eyepieces that have their focal planes at the 1.25" barrel shoulder--it makes the 14mm parfocal with the other Delos, all of which have their focal planes 0.25" below the shoulder.

Exactly!  I figured that out long ago when shopping for a 14mm to replace my Pentax XL once presbyopia set in.  I'm already annoyed by having to crank my focuser a 0.25" outward to bring the 10mm Delos to focus.  I suppose I should just add 0.25" of O-rings to it and be done with it.  Such a simple solution is not possible with the 14mm Delos, thus I went with the 14mm Morpheus which does focus more or less at the shoulder.

8 minutes ago, Don Pensack said:

Judging by what I see in the field and comments from observers, most people simply don't care whether their eyepieces are parfocal and only run into an issue of in-travel if the scope runs out of the necessary amount of it.

It makes swapping eyepieces a royal pain when searching for the best magnification.  That, and coma correction is not ideal with the fixed distance of the GSO CC when not focusing at the shoulder where I set it.

Just now, Don Pensack said:

Also look for EOFB in the 13mm AF70, where it is quite excessive.

It's so hard to get past the rainbow stars in the last 30% of the field in the 13mm AF70 that I've never noticed EOFB out there.  That level of chromatic aberration would surely smear any faint fuzzies out there into even more unrecognizable blobs.

You're right about EOFB.  It's way too subtle to show up in my images.

The worst for EOFB I've found is the 12mm NT4.  It has a lightening that starts out bright at the edge and gradually gets dimmer toward the center, but never goes away completely.  I swapped between it and the 12mm ES-92, 14mm Morpheus and 10mm Delos, and none of them were showing any field brightening like that.  I'll have to check the 12.5mm APM for that next time I'm out since I didn't have it at the time I noticed EOFB in the Nagler.  I can't recall it being objectionable so far in it, but I also haven't been faint fuzzy hunting with it.

My images also don't reveal field curvature since the taking lens has quite a bit of depth of focus mimicking human focus accommodation.

I was kind of put off by the 14mm Delos needing a negative profile 2" to 1.25" adapter to make it parfocal with the majority of my eyepieces that focus at their shoulder.  I'm not even sure it would fit down inside the necessary distance thanks to its rather thick lower barrel.  Tele Vue sells their In-Travel Adapter ($53!!!) for it, but I'm not sure it actually recesses the eyepiece a full 0.25" when you figure in the adapter's lip thickness.  Here you've already paid a premium for the eyepiece, and it's not even parfocal with most other eyepieces, nor does it come with an adapter to help it be more parfocal.

My 25mm Paradigm (BST Starguider) already won't come to focus in my Dob's low profile focuser with the GSO CC in place, so I know I'm close to my in-focus limits.  I've already shifted my primary mirror forward as much as I'm comfortable doing.  My focuser's 2" to 1.25" adapter is already a zero profile adapter, so that leaves a negative profile adapter as my only option.

12 hours ago, Mr Spock said:

In terms of image quality the Morpheus wins. But it sure is ugly... 

I'm most off-put by the cartoonish font and color used for text on the Morpheus.  I think the color was dictated by the glow in the dark requirement.  I can't think of another eyepiece using a fat outline font.

Compare it to the 14mm Pentax's refined looking metal plate and lettering that just exudes Japanese quality.  That eyepiece is 24 years old and still looks terrific!  I used it during every observing session for 18 of those years, so it wasn't mollycoddled, either.

The 12.5mm APM Hi-FW yields a wider true field of view than the 14mm Morpheus (19.8mm field stop vs 18.4mm FS).  It's nicely sharp across the field as well and quite usable with eyeglasses (both have 18mm of measured, usable eye relief).  It has a very different distortion (barrel) from the others on your list (pincushion) in that it doesn't stretch the edges but compresses them instead.  In fact, it is slightly wider than my 12mm ES-92 (19.8mm FS vs. 19.7mm FS) because of this.  I'm still comparing it to the ES and Morpheus, but so far, it's a winner.  I think Don may have used the 12.5mm APM as well.

My 14mm Pentax XL has noticeable field curvature.  Reportedly, the 14mm XW did not fix this shortcoming.  However, if you're young and your eyes still focus, you won't notice it.  It is astigmatism free at the edge once refocused.

To my eye, the 14mm Morpheus has a slight bit of field curvature and astigmatism at the edge that can't be focused out.  I disagree with Don on this point.  He doesn't see either, so YMMV.  It's extremely minor, but it's there in a field flattened f/6 refractor.  By comparison, the 9mm Morpheus has neither to my eye and is just about as perfect as my 10mm Delos, only with a wider AFOV.  That, and it has just a slightly smaller FS (12.5mm vs 12.8mm).

Here's some images of and through eyepieces I own in the 12mm to 15mm range:

1 hour ago, JeremyS said:

Every time I move an eyepiece on I come to regret it.

So the collection grows

You and me both.

1 hour ago, cajen2 said:

Why aren't I rich? (Because I like astronomy, I suppose!) 🤔😄

I wish I'd had the disposable income I have now back when my back was strong and my eyesight super sharp (and focusable).  Ahh, to be young and poor again.

My 3.5mm Pentax XW is fantastic, but gets very little productive use, so I've toyed with the idea of selling it.  When I want powers that high, I generally find my binoviewer working at 3x with 8-24mm zooms yields a more detailed image.  However, it nicely completes my 3.5mm XW, 5.2mm XL, 7mm XW, 9mm Morpheus, and 10mm Delos power progression.  I sometimes wonder if I should get the 6mm and 8mm Delos for filling in the holes.

My favorite is the vintage, Japanese made Meade Series 400 #140 APO 2x Barlow.  They come up used on this side of the pond all the time for $40 to $65.  I have several in different usage configurations.  One is as a Barlow for 2.4x, one is as a binoviewer GPC/OCS/OCA to reach focus and boost magnification by 3x, and one is combined with a 0.5x reducer and 45mm of spacer tubes to achieve 1.0x with the binoviewer when used in a Newtonian.  They're highly versatile.  I've even put the nosepiece on the front of a 1.25" diagonal and the 0.5x on the binoviewer to get to a vignetted 0.7x power.  Screwed onto an eyepiece yields 1.6x.  All the measurements were taken with a 14mm Pentax XL that focuses at its shoulder.

I have the GSO 2" ED 2x that's also sold as Stellalyra and many other brands.  Look for the Taiwan label to distinguish it from the Chinese variants.  It is very good and compatible with the TV Panoptic Barlow Interface to make a poor man's Powermate.  It yields 2.1x natively.  I haven't measured the other usages' magnifications.

@John usually recommends the Baader Q-Turret 2.25x Barlow, especially as used with a 7.2mm - 21.5mm zoom.  However, because of the way it screws into filter threads, your eyepiece can't have its field lens down near to bottom of the insertion barrel.

I enjoy using my 72ED refractor for low power sweeping of the skies.  In particular, I can pick out large star clusters and associations that are not obvious at higher powers.  Rich star fields in Orion and Perseus come to mind.

I have the 3.5mm Pentax XW and find myself using it only a few times a year, such as during Mars oppositions.  It's super sharp and with no obvious flaws.  However, I've found that at high powers, I see much more on planets with binoviewers.  My floaters become much more manageable, and two eyes process the image much better than one.

I would probably look for a quality Barlow or telecentric magnifier myself and just reuse my existing eyepieces at higher powers.

I have the entire line except for the 3.2mm.  The 5mm, 8mm, and 12mm are all very good.  The only comment from an experienced observer about the 3.2mm that I've read is from Jon Isaacs over on CN:

At F/5-F/7, the 25mm and the 18mm show significant off-axis astigmatism. I still use them but the views are not optimal.  Probably better at F/10.

The 12mm, 8mm, and 5 mm are quite sharp across the field even at F/5.  

The 3.2mm, it's a little weird off-axis at F/5, I haven't quite decided about it.  

2 hours ago, Mike Q said:

I wouldn't agree with the I just got lucky on the optics.  GSO is making some pretty solid mirrors these days.  I have a friend who has a 16 inch Orion GoTo and it gives images that are on par with scopes that cost 2 or 3 times the cost.

Teeter Telescopes offer(ed) GSO mirrors as the lowest cost mirror option for their telescopes.  They must have been pretty good to be putting them into multi-thousand dollar telescopes.  Why would you risk your custom telescope business's reputation on crappy mirrors?

Yes, mine is intended for groomed lawns and fields, such as setting up on a soccer field for a star party after driving my van to the edge of the field.  Driving on such fields is highly discouraged. 😉

Notice that the high frequency detail is preserved (the pinpoint city lights) while low frequency detail is compromised (the subtle sky and sea tones).  I'd guess they're using jpeg compression at a fairly aggressive setting.  The jpeg algorithm tries to preserve high frequency detail in a relatively small area at the expense of large swaths of low frequency detail under high compression.  There isn't much you can do to change how FB compresses image downloads.

2 hours ago, cajen2 said:

It's much easier to carry with the bag, either with the handles or over the shoulder. I really wouldn't like to shift it inside a blanket. I may have to trek hundreds of yards with it to find a viewing spot.

Oh, I just carry my Dob by the handles on each part, but I never carry it more than 100 feet.  My 15" Dob has its own flat dolly with heavy duty castors and pull rope to move it about.

What is the diameter of the stock lazy Susan versus the diameter of the ground board and rocker box?

40 minutes ago, Mr Spock said:

@Steve I don't see what there is to be faulty. It's just pieces of particle board bolted together!

Here it is wobbling.

 

IMG_0758.MOV 75.53 MB · 25 downloads  

 

After reviewing your video, the first thing I notice is it seems to wobble on the AZ axis.  This is probably a function of the undersized bearing for it.  Ideally, the bearings should come all the way out to the edge of the AZ board.  You could substitute Teflon pads riding on textured FRP wall board or other nubbly, yet glossy, board.

Try separating the rocker box from the ground board and repeat the rocking action again with the rocker box directly on a smooth, solid surface.  This would show how much improvement is possible by redesigning the AZ bearings.

I can't really tell where the wiggliness in the ALT bearing is coming from.  It's hard to tell if it's rocker box flexure or simply the long tube amplifying small flexure at the pivot axis.  If that is the case, you'd need to increase the diameter of the side trunnions to reduce the flex coming from that connection point.

This is really an engineering problem.  Isolate the cause of the "failure" and then try to find a fix, or at the least, a workaround.

Even giant, custom Dobs exhibit a bit of wobble sometimes in some orientations and motions.  Trying to rotate around Dobson's Hole at zenith comes to mind.  This is where the Mag 1 Portaballs had it in spades over the traditional two axis Dob design.

If traveling by car, I'd just wrap a shipping blanket around the tube to protect it from dings and knocks.  I suppose the bag would be better for mass transit, though.

15 hours ago, vlaiv said:

There is also triplet version.

https://www.teleskop-express.de/shop/product_info.php/info/p14015_TS-Optics-APO-Refractor-96-576-mm---FCD100-Triplet-Lens-from-Japan.html

Just a wee bit of a price jump there (~$650 or 70%).  I'll wait and pick up a used one in a decade like I did with my TS-Optics Photoline 90mm FPL-53 triplet for about 60% of new price.