238 replies to this topic

[Captain Quark]

Explore Sci 92° Series - wishing for additional focal lengths to go with the 12mm & 17mm

Me too.

[ihf]

The new Houdini 20 mm 86° Coma-Correcting Eyepiece is the first eyepiece on my 2025 list. It seems to have good enough eye relief for my glasses and is light enough for small travel reflectors without the need for a dedicated coma corrector.

[Epick Crom]

The new Houdini 20 mm 86° Coma-Correcting Eyepiece is the first eyepiece on my 2025 list. It seems to have good enough eye relief for my glasses and is light enough for small travel reflectors without the need for a dedicated coma corrector.

Hmm interesting,  this is the first time I've heard of this eyepiece..

 

Thanks for the information!

[stonewoll]

I am pretty content with my current stable of eyepieces, but I would like to try out and compare the Nikon NAV-SW with my delites.

[dawnpatrol]

I was just thinking about this the other day. After recently acquiring the last of the bino pairs I've wanted to fill out, I realized, for the first time ever, that I really only have one major want: The Leica zoom is really the last eyepiece on my wishlist. 

[ausastronomer]

Prior to purchasing the 30mm UFF 1/2 way through last year I hadn't purchased a new eyepiece in 15 years.

 

I didn't need to buy that one and I don't need to buy any more into the future, however I am keen to try Roberts 20mm Houdini Coma Correcting eyepiece, if it is reasonably priced.   I don't need it, as I have 30+ high quality eyepieces and 2 Televue Paracorrs, but if it's reasonably priced I'm keen to spend a couple hundred $$$ to try it out. Coma correcting eyepieces certainly aren't new, I first used a Coma correcting Pretoria eyepiece over 30 years ago.  The Pretoria had tight eye relief and a narrow AFOV. What's new is a Coma Correcting eyepiece with 20mm of Eye Relief and an 86 degree AFOV.

 

Cheers

[manolis]

The new Houdini 20 mm 86° Coma-Correcting Eyepiece is the first eyepiece on my 2025 list. It seems to have good enough eye relief for my glasses and is light enough for small travel reflectors without the need for a dedicated coma corrector.

thanks to your link now it's in mine too !!   , but i will wait for the 28mm.

i knew there was a reason i didn't pull the trigger on the 32 masu in black friday !!

[Jon Isaacs]

The new Houdini 20 mm 86° Coma-Correcting Eyepiece is the first eyepiece on my 2025 list. It seems to have good enough eye relief for my glasses and is light enough for small travel reflectors without the need for a dedicated coma corrector.

 

To correct coma, negative coma is added.  That means coma correction adds coma to coma free scopes like refractors.  A dedicated coma corrector allows one to use all ones eyepieces in all ones scopes. 

 

Jon 

[ihf]

To correct coma, negative coma is added.  That means coma correction adds coma to coma free scopes like refractors.  A dedicated coma corrector allows one to use all ones eyepieces in all ones scopes. 

This concern has been addressed by Houdini. The added coma is not visible at f/8 or slower scopes, like most refractors or Cats. Now those folks with flat field f/5 Petzval refractors will have to keep other dedicated eyepieces around. Everyone not owning a TV NP 101 or BabyQ has no reason to hold onto eyepieces that were not optimized for use in fast reflectors. (Well, so much for the sales pitch. I think we will see how well it works soon enough.)

[vrodriguez2324]

Any good quality 40mm plossl. 

[Jon Isaacs]

This concern has been addressed by Houdini. The added coma is not visible at f/8 or slower scopes, like most refractors or Cats. Now those folks with flat field f/5 Petzval refractors will have to keep other dedicated eyepieces around. Everyone not owning a TV NP 101 or BabyQ has no reason to hold onto eyepieces that were not optimized for use in fast reflectors. (Well, so much for the sales pitch. I think we will see how well it works soon enough.)

Well...

 

There is still significant coma at F/8.  The coma free field at F/8 is 11 mm.  If the coma corrector fully corrects the coma in an F/8 Newtonian, it is adding coma at F/8 inch a refractor.

 

There are plenty of refractors F/8 and faster.  At F/6, the coma free field is 4.75 mm, at F/7 it's 7.5 mm.  

 

Jon

[Houdini]

Maybe I can chime in here.

 

My test report did not say that "The added coma is not visible at f/8 or slower scopes". On the contrary, I wrote "The eyepiece shows a sharp, flat image with some inverted coma at the edge, but not much."

 

A very sharp eyepiece like the Houdini 20 is bound to show the inverted coma, even at f/8, but it's not very harmful to the image - the edge sharpness in the 6" f/8 refractor was still about the same as with the Panoptic 24.

 

At f/8, a very large part of the field is not really affected by the coma (or the reverse coma of the same magnitude generated by the Houdini eyepiece). That's why nobody uses a coma corrector in f/8 Newtonian telescopes, and that's why it's OK to use a coma-correcting eyepiece in f/8 refractors.

[Speedy1985]

I'm going to fill in some holes with TV Ethos to give me more options for when I get to darker and steadier locations. The 10mm will likely be the first I hunt down.

[Floaters]

I don't really need anything, but I'll try to gather the few remaining AT UWAs and Starguiders for completist reasons.

If I tap my maples this spring and end up striking oil or gold I might explore some Tele Vue lines

[Rick-T137]

My "to buy" list is empty as I just bought a set of Celestron Plössls (and I'm pretty pleased with them - great value!).

 

If we're talking about wishing... then I'd wish for a complete set of DeLites plus a 24mm Panoptic. That would probably make me forget my Plössls is a hurry!

 

Edited by Rick-T137, 12 December 2024 - 01:48 PM.

[Bkmiller4463]

Ethos 6.  Will probably sell my Delites 3, 4 and 7. I find I don’t use them all that much, and I can Barlow the 14, 9 and new 6 if I want the magnification. 

[Rick-T137]

My "to buy" list is empty as I just bought a set of Celestron Plössls (and I'm pretty pleased with them - great value!).
 
If we're talking about wishing... then I'd wish for a complete set of DeLites plus a 24mm Panoptic. That would probably make me forget my Plössls is a hurry!

OUCH! I just figured out why I haven't gone to DeLites yet...
 


They are above my pay grade for now...

[FirstSight]

None. I have a complete enough eyepiece collection - got evrything I want, and more than I can find time to look through.  I'd rather spend discretionary money now on buying more guitars than I could ever find time to play..

[Steve Cox]

None here either. Just sold all my TV eyepieces and down to one set of Hyperions now, with plenty of eye relief and much more comfortable.  Also just re-foamed my eyepiece case to accommodate. I guess if I have a 2025 wish it would be that I don't get a desire to buy anything else.

[SandyHouTex]

I have a ZAO I 6mm, 10mm, and 16mm.  I wouldn't mind the 25mm for a "reasonable" price.

[sw196060]

Everything.

I've pretty much cleared out all my eyepieces and am starting over.

I am eyeing the AT XWAs for 7 and 13mm and a 2" ep around 30 - 35mm.

[aatt]

Those ES 92 degrees sound pretty sweet. You can’t beat waterproofing for cleaning purposes. My other ES eps are a snap to clean. No capillary action to worry about.
The 92’s sound equivalent to any Televue… that being said I am pretty happy with my eyepieces as I have a pretty good range of ep’s for various applications. My upgrades from the budget plossls I started with are quite good, maybe not perfect, but very satisfying.

[swsantos]

If a “wish list” could include eyepieces not yet(?) available, then a full set of Apollo eyepieces at a not-limited-edition price would be great.

[R.Kelley]

If a “wish list” could include eyepieces not yet(?) available, then a full set of Apollo eyepieces at a not-limited-edition price would be great.

Absolutely, I'm wishing for a full set of Explore Scientific 92°s, but Apollos would be a good substitute.

[BadClams]

I’ve been wanting a Nikon-NAV 17 HW for a while…. I was hoping to be enticed by a holiday sale, but no such luck.