Do anyone have any experience with the new TMB monocentrics? Are they worth the money? What about the statement that "the small field prevents the eye to wander away from the object (planet)"? Have anybody compared the monocentrics with common orthos?
Monocentric eyepeices
Started by Inge_S, 11/05/2003 03:07PM
Posted 11/05/2003 03:07PM
Opening Post
Posted 11/05/2003 03:15PM
#1
Inge:
There is a cloudy nights review of these.
I believe this is the link:
http://www.cloudynights.com/eyepieces2/tmb.htm
I just purchased a 22mm Nagler for my Meade 12 LX200 and Saturn looked great. I also purchased a 13mm Nagler, which should be arriving shortly. I have heard it performs well on the planets, too.
Gregg
Augusta, Maine
There is a cloudy nights review of these.
I believe this is the link:
http://www.cloudynights.com/eyepieces2/tmb.htm
I just purchased a 22mm Nagler for my Meade 12 LX200 and Saturn looked great. I also purchased a 13mm Nagler, which should be arriving shortly. I have heard it performs well on the planets, too.
Gregg
Augusta, Maine
Posted 11/05/2003 05:30PM
#2
Yes. We've discussed it some here in the Astromart forums. Try [Search Forums] between, say, June and present on TMB or Supermonos or monocentrics in the Eyepieces forum. That should bring up some threads.
Without a doubt, the Supermonos have less scatter, and they're surprisingly well-corrected even in faster scopes, with the most bothersome off-axis aberration being field curvature in fast scopes, particularly fast scopes with a little curvature of their own, like fast Newts. You may hear talk about them being "sharper" than this or that high-quality eyepiece, but note that this usually comes when the target has low-contrast detail, so I personally think that in accord with optical expectations, they are "just as sharp" as the better competition and that their design and implementation as one super-high-quality optical group with just two air-to-glass surfaces gives them a significant contrast edge.
Eye relief is a little better than Abbe orthos at the same focal length, and it is possible to get used to the 30 degree apparent field. However, I think this will be easiest for people who consistently stick to narrow-field eyepieces. Eventually I found the shock of going back and forth between a SuperMono and type 6 Naglers to be too much, and for me using Dob-Newts, the reduction in scatter and contrast benefits weren't enough to overcome a desire to reduce my investment in equipment somewhat. I suspect that in fine APOs the reduction in scatter is more pronounced and a much stronger plus, which is to say, I think I may have chosen differently if I had an APO f/6 or slower instead of premium Dob-Newts.
--
Mike
Without a doubt, the Supermonos have less scatter, and they're surprisingly well-corrected even in faster scopes, with the most bothersome off-axis aberration being field curvature in fast scopes, particularly fast scopes with a little curvature of their own, like fast Newts. You may hear talk about them being "sharper" than this or that high-quality eyepiece, but note that this usually comes when the target has low-contrast detail, so I personally think that in accord with optical expectations, they are "just as sharp" as the better competition and that their design and implementation as one super-high-quality optical group with just two air-to-glass surfaces gives them a significant contrast edge.
Eye relief is a little better than Abbe orthos at the same focal length, and it is possible to get used to the 30 degree apparent field. However, I think this will be easiest for people who consistently stick to narrow-field eyepieces. Eventually I found the shock of going back and forth between a SuperMono and type 6 Naglers to be too much, and for me using Dob-Newts, the reduction in scatter and contrast benefits weren't enough to overcome a desire to reduce my investment in equipment somewhat. I suspect that in fine APOs the reduction in scatter is more pronounced and a much stronger plus, which is to say, I think I may have chosen differently if I had an APO f/6 or slower instead of premium Dob-Newts.
--
Mike
Posted 11/05/2003 06:38PM
#3
Hello there Inge,
I have the 5mm and 4mm and despite my great fondness for
my Radian eyepieces, I now use the SuperMono almost exclusively on the planets. However on the Moon, I still prefer the Radian's wide view, but will use the SuperMono to zero in on a crater or feature. Also, to see Jupiter
and all of the moons, I still prefer the Radian. I also prefer the wider view of the Radian on DSOs. All in all, I like the SuperMonos so much I got the 6mm from Thomas Back as well. I also like the SuperMono on my 8-inch f/6 Discovery PDHQ Dob. However because of the nudging mount, I rarely use the SuperMonos on it (until I get a EQ platform someday). Indeed its 30d AFOV seemed to help maintaining attention on the object, but I strongly recommend its use on a driven mount.
Please have a look some of the comparison here.
http://members.cox.net/ronby/Solar-System/index.htm
Ron B[ee]
I have the 5mm and 4mm and despite my great fondness for
my Radian eyepieces, I now use the SuperMono almost exclusively on the planets. However on the Moon, I still prefer the Radian's wide view, but will use the SuperMono to zero in on a crater or feature. Also, to see Jupiter
and all of the moons, I still prefer the Radian. I also prefer the wider view of the Radian on DSOs. All in all, I like the SuperMonos so much I got the 6mm from Thomas Back as well. I also like the SuperMono on my 8-inch f/6 Discovery PDHQ Dob. However because of the nudging mount, I rarely use the SuperMonos on it (until I get a EQ platform someday). Indeed its 30d AFOV seemed to help maintaining attention on the object, but I strongly recommend its use on a driven mount.
Please have a look some of the comparison here.
http://members.cox.net/ronby/Solar-System/index.htm
Ron B[ee]
Posted 11/07/2003 04:53PM
#4
Hi Inge,
In considering the TMB monos keep in mind that they have a limited AFOV. I bought the 4 mm mono for my TMB 105/650. While the eyepiece was quite sharp and contrasty on axis I found the narrow field of view combined with the field cuvature, in this fast scope, to restrict the useable field to ~25 degrees. This proved to be two much of an hassle with the Giro mount I use - too much nudging to keep things centered and focused. In all, I found my 4 mm UO Ortho to be better suited to my particular setup. I might feel differently if I had a GEM.
Don
In considering the TMB monos keep in mind that they have a limited AFOV. I bought the 4 mm mono for my TMB 105/650. While the eyepiece was quite sharp and contrasty on axis I found the narrow field of view combined with the field cuvature, in this fast scope, to restrict the useable field to ~25 degrees. This proved to be two much of an hassle with the Giro mount I use - too much nudging to keep things centered and focused. In all, I found my 4 mm UO Ortho to be better suited to my particular setup. I might feel differently if I had a GEM.
Don
Funding Member
