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Sky & Tel Article: TMB Monos

Started by Rod Kaufman, 06/28/2004 07:43AM
Posted 06/28/2004 07:43AM Opening Post
I found the Sky and Telescope article on TMB monos to be interesting and informative. Standards of performance stressed scatter/contrast and resolution. The difference in contrast between the TMBs and other eyepieces was described as "subtle" and the author noted,"This is a far cry from some reports I had read on the Internet that proclaimed that the TMB's contrast "blew away" other eyepieces". The author also states, "can I conclude the TMBs are in fact superior planetary eyepieces? I never saw a difference that was pronounced enough that I would be comfortable making that statement without qualification".
One important point not mentioned in this article is cost-effectiveness. If, as the author states, TMBs are at least as good as the other eyepieces tested(but not significantly superior as vendor hype has suggested) why pay over $200.00 for an 8mm TMB versus $89.00 for a 8mm Televue plossl which provides a much larger AFOV without astigmatism?
Posted 06/28/2004 12:14PM #1
Rod,
Now you know as good consumers we are supposed to drool and buy anything that is reported to be better than the inexpensive spread! wink
I have always wondered whether they were worth the extra cost and loss of FOV. I think I will stick with my "Inexpensive" Orthoscopics and Ultrascopics for now.
Ohh, the shame of it! smile
Floyd

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
Amateur Imager
Posted 06/28/2004 12:31PM #2
FYI,

This review was discussed at tremendous length over on the TMB Yahoo! group. Eventually, Thomas Back (Mr. TMB himself), who was understandably less than happy with the review, got the eyepieces back and tested them. He discovered that he had sent a batch of bad eyepieces (all but one had astigmatism).

What Mr. Back attempted was to send a random sample of untested eyepieces from a recent batch so as to prevent any hand-picking of samples. Which is actually not SOP, as he does test every eyepiece before shipping them to paying customers.

I have not followed the thread lately, but my understanding is that the Monos will be reviewed again in a later issue.

FYI, I do not own any of these EP's myself, so I have no say either way.

Eric
Posted 06/29/2004 02:22AM #3
Hi All

I see the customers talking here do not have any input, so let me give some input

1, blackened edges: Blackened egdes are necassary only, in not well baffled, fiedlstopped eyepieces. ZThe famous Zeiss Abbe Orthos does not have either a balackened edge and it does not help or improve anything in the TMB Monos due the perfect baffling. I know many eyepieces with blackened edges and ghosting images or reflections

2,3 total runs of eyepieces have been made so far , abouu 3000 pc in total. In first run about 10 pc showed a optical problem and unsharp fieldstops. In second run about 2 or 3 showed a optical problem and a handfull still a fieldstop not total perfect round
In third run, non of the eyepieces have had either a optical or a fieldstop deffect. This is a sign of a great improvement of the manufactor. Also take into account from 3000 eyepieces, about 30 pc showed a problem, most of them in first run, a few in second run , non in last run, but even in total this is about 0.1%, in a big serial production anybody would he happy to have so small quantitys blames.

Also the TMB Mono prooved already all over the world, to bet visible the famous Zeiss and Pentax orthos, reviewed by hundrets of users. Now a reviewer of a magazin comes using a fast reflector with attached comacorrector to review a high end planetary eyepiece. Anybody who is doing serious planetary Observing knows he need a, a high quality telescope, b, a very good seeing, c, a perfectly 100% collimated telescope. Anybody who owns a F/4.5 newton knows how extremly difficult it is to get and also hold such telescope in perfect collimation.
Under less then perfect overal conditions, nobody can see the diffrence between a standart quality and highest quality item.

All this is of course no excuse that 3 bad eyepieces have gone to a magazin review, but we talking about 4 pc total found yet from second run, which showed a problem and non of last run.

The chance was till the second run to get a poor eyepiece by 0.1%, the chance after third run so far is 0,0 %

Take such test telescope and compare a cheap chinese Plössl for $ 20 against a $ 80 Tele Vue Plössl and you may not see any diffrence.
But if you use a excellent Planetary telescope, excellent collimated, under excellent seeing, then you see a diffrence, for shure.

Sky and Telescope did with this review a excellent job to protect the market for one of here biggest advertiser, but this method is very coman in all magazins, you get what you pay for, this is also valid for advertisers. Pay a premium each month and you get many and positive reviews, pay small or nothing and you get kicked into the ass

Markus

clear skies

Markus Ludes
APM-Telescopes/Germany