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TMB Super Monocentric Eyepieces完全深度评测

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发表于 2008-3-24 21:34:32 | 只看该作者 |只看大图 回帖奖励 |倒序浏览 |阅读模式

The 10mm, 8mm, 6mm, 5mm, and 4mm TMB Super Monocentric Eyepieces
这篇评测详细的分析了大家所熟知(各位DX最近评得很火的行星目镜)TMB supermono目镜
Overview A new eyepiece was recently introduced by Thomas M. Back of TMB Optical based on the Monocentric eyepiece design. The original monocentric design was introduced in the late 1800's by Adolf Steinheil. It had a three element cemented triplet with only two air-to-glass surfaces, which is the minimum of any eyepiece design, and a 30 degree apparent field of view (AFOV). In an eyepiece, fewer glass surfaces will result in less light scattering due to the elements and their coating. Thus, there will be greater light transmission. This helps to bring out low contrast details on the planets and produces a brighter image. The monocentric design got its name because all three lenses have one common center of the radii curvative.
For a number of years Zeiss Monocentric (0.965") were considered the ultimate planetary eyepiece. Thomas Back studied the original Zeiss monocentric design and through computer analysis figured out a way to create an all-new eyepiece design. The design uses super low reflection/narrow angle scatter multicoatings and two of today's exotic Schott high index glasses. The Schott glass is water white, and does not add any unnatural color. In addition his partner, APM Markus Ludes of Germany, found a Zeiss subcontractor to manufacture the TMB eyepieces (TMB). This allows for the use of some of the best polishing equipment available today to be used in the manufacture of these eyepieces.
This new design offers more eye relief, better on and off-axis correction, and a slightly wider AFOV of 32 degrees than the original design. It reduces also light scatter, increases contrast, and increases light throughput to approximately 99%. As we shall see these factors play an important part in how well the eyepieces perform when observing the planets, Sun, Moon, bright stars, double stars, and deep-sky objects.
The initial run of the eyepieces that began delivery in August of 2003 included a 4mm, 5mm, 6mm, 8mm, and 10mm. These eyepieces are not parafocal with each other but the next set of eyepieces available in December 2003 is. These will include the 4mm, 5mm, 6mm, 8mm, and 10mm as well as 7mm, 9mm, 12mm, 14mm, and 16mm. Note that there will only be a slight difference where original version eyepieces and the parafocal version eyepieces come to focus. Therefore an eyepiece from the original run and one from the parafocal run can be still be used in a binocular viewer by adjusting the focus of one eyepiece.

[ 本帖最后由 siqingtan 于 2008-3-25 09:53 编辑 ]


参与人数 1经验 +10 收起 理由
我爱祖祖 + 10 感谢供稿。


?楼主| 发表于 2008-3-24 21:34:57 | 只看该作者

The 16mm, 14mm, 12mm, 9mm, and 7mm TMB Super Monocentric Eyepieces
As of December 2003 the price of the TMB 4mm, 5mm, 6mm, 8mm, and 10mm eyepieces are $225.00 each, while the 12mm, 14mm and 16mm eyepieces are $250.00 each. The eyepieces are available from TMB Optical, APM Markus Ludes, and other dealers around the world. I ordered my eyepieces from TMB Optical, and this is my first purchase from them.
In the TMB the eye relief is 0.85x the focal length, so 10mm will have 8.5mm of eye relief. By comparison the eye relief of a Plossl is 0.75x the focal length, while an Orthoscopic is 0.80x the focal length. Here is a table that shows the eye relief of the TMB:
TMB Focal Length Eye Relief
16mm 13.6mm
14mm 11.9mm
12mm 10.2mm
10mm 8.5mm
9mm 7.65mm
8mm 6.8mm
7mm 5.95mm
6mm 5.1mm
5mm 4.3mm
4mm 3.4mm
At the shorter focal lengths, such as the 6mm and 4mm, the eye relief of the TMB is slightly better than that of the Zeiss Abbe Orthoscopic eyepieces. In practice I found the eye relief of the TMB to be comfortable when observing. Observers who must wear glasses while observing may find eyepieces with longer eye relief such as the TV Radians with 20mm eye relief to be more comfortable. Another option would be to use the longer focal length TMB that have better eye relief in conjunction with a 1.8x TMB 1.25" ED Barlow planned for delivery in February 2004. This Barlow will be designed to match or exceed the performance of the Zeiss 1.25" ED Abbe barlow.
The following table lists the eyepieces that were compared with the TMB in this test. The AFOV of the TMB is 32 degrees, the Zeiss Abbe Orthoscopics (1.25") is 45 degrees, the Pentax SMC Orthoscopics (0.965") is 42 degrees, and the TeleVue (TV) Plossl's is 50 degrees:
TMB Super Monocentrics Zeiss Abbe Orthoscopics Pentax SMC Orthoscopics TeleVue Plossls
10mm 10mm 9mm -
8mm - 9mm and 7mm 8mm
6mm 6mm 7mm -
5mm 6mm and 4mm - -
4mm 4mm - -
Note that in the cases where an exact match for an eyepiece in each focal length was not available, such as the TMB 5mm, I performed a generalized comparison with the next closest focal length of the other eyepieces.

[ 本帖最后由 siqingtan 于 2008-3-25 09:50 编辑 ]
?楼主| 发表于 2008-3-24 21:35:23 | 只看该作者
Eyepiece Comparisons When I received the TMB I took them out of their boxes and carefully inspected them. I was impressed by their quality. They have a solid feel to them yet are relatively lightweight. The TMB are threaded for 1.25" filters, have a low reflection top surface to reduce stray light reflections, and have a slightly elevated rubber ring around the edges that helps to block stray light. The outside of the barrels has a safety groove, and the inside of the eyepiece barrels has a flat black interior. All eyepieces come with protective plastic caps. I noted that since the first TMB eyepiece set is not parafocal the eyepieces all have the same height.
To check the light transmission of the TMB, Zeiss, Pentax, and TV Plossl eyepieces I held them up against white paper. The TMB showed a brighter, more pure white image than the Zeiss or Pentax, while the TV Plossl was not as bright and appeared slightly yellow. I inspected also the coatings on the eyelens of each of the eyepieces. The coatings in the TMB appeared darker then the others, and when held up to a bright light seemed to show less reflections. When compared to the other eyepieces, I believe the whiter image and the reduced reflections in the TMB were a result of the Schott glass and super low reflection/narrow angle scatter multicasting it had.
The TMB eyepieces, like the Zeiss, Pentax, and TV eyepieces, have a color band around the outside of the eyepiece housing to distinguish one focal length eyepiece from another. However they are much wider and distinctive on the TMB and I found it easy to determine which focal length was which when using them during the day. The same was true when using them at night with a red filtered flashlight. Some observers have reported that they found it difficult to read the lettering of the TMB 8mm eyepiece band when using a red filtered flashlight at night due to the color of the band. So starting with the December 2003 delivery of the TMB the color band of the TMB 8mm will be changed to a more contrasty color.

A Pentax 7mm SMC Orthoscopic eyepiece in a 1.25"/0.965" adapter next to a TMB Super Monocentric 6mm eyepiece. Note the wider color band and larger lettering on the TMB eyepiece.

[ 本帖最后由 siqingtan 于 2008-3-25 09:48 编辑 ]
?楼主| 发表于 2008-3-24 21:35:43 | 只看该作者
Before comparing the eyepieces with the TMB I carefully cleaned the Zeiss Abbe Orthoscopics, Pentax SMC Orthoscopics, and TV Plossls. For the past seven years the Zeiss Abbe Orthoscopics and Pentax SMC Orthoscopics were the eyepieces I used most for my planetary, lunar, solar, and high power views of deep-sky objects. I have compared the Zeiss and Pentax with other eyepieces such as the Aus Jena Orthoscopics (0.965"), Brandon Orthoscopics, Clave Plossls, Meade Research Grade Orthoscopics, TeleVue Naglers, Plossls, and Radians, and University Optics Orthoscopics. Based on these comparisons I felt that the Zeiss and Pentax were the finest eyepieces I have used since I began observing in the early 1970's in terms of their light transmission, contrast, lower light scatter, and overall sharpness.
Prior to purchasing the TMB I wondered if they would perform better than the Zeiss and Pentax Orthoscopics. Also, since I often use my telescopes on homemade Dobsonian-style alt-az mounts that do not have tracking, I wondered if I would find these eyepieces less desirable to use due to their smaller field of view than either the Zeiss or Pentax. A smaller field of view meant I would have to re-center the object more often when observing.
The eyepiece comparisons were conducted during numerous observing sessions over a five-month period using my AP 7.1" f/9 and AP 5.1" f/8.35 refractors. The AP 7.1" was used on both the homemade Dobsonian style-mount, as well as a German equatorial mount. The AP 5.1" was used only on the homemade Dobsonian-style mount. A friend of mine who was interested in trying out the TMB eyepieces brought over his AP 92mm f/4.9 refractor on a German equatorial mount on several occasions. During some of these eyepiece comparisons I used an AP/Baader/Zeiss binocular viewer that had a 1.25x corrector. This increased the focal ratio of the AP 92mm from f/4.9 to f/6, the AP 130mm from f/8.35 to f/10.3, and the AP 180mm f/9 to f/11.3. This provided an opportunity to test the eyepieces using telescopes with focal ratios that ranged from f/4.9 to f/11.3. It was noted that at f/4.9 the Zeiss, Pentax, and TMB showed some field curvature at the edge of the field of view. At f/8.35 and longer the Zeiss, Pentax, and TMB were pretty much sharp right to the edge.
A variety of objects were observed during these eyepiece comparisons, including the solar system objects such as the Sun, Moon, Venus, Mars, Jupiter, and Saturn, as well as double stars, bright stars, and deep-sky objects. I enjoy using my TV Naglers and Panoptics when observing deep-sky objects, but for pulling out the last bit of fine detail I have been using the Zeiss and Pentax.
An AP Maxbright diagonal was used when observing deep-sky objects, bright and double stars, and sometimes when observing the Moon and planets. Most of the time an AP/Baader/Zeiss binocular viewer was used for observing the Sun, Moon, and planets. When using the binocular viewer, it was often possible to have a TMB eyepiece inserted into one of the eyepiece holders and a Zeiss, Pentax or TV inserted into the other and, after adjusting the height of the eyepieces, bring both to focus. To insure that the differences noted during testing the eyepieces in this manner were not due to the binocular viewer the TMB and Zeiss, Pentax or TV were switched from one of the holders to the other.
Daylight Tests
On the first day I received the eyepieces I set up the AP 130mm f/8.35 refractor on a home-made alt-az mount to observe the Sun. However the seeing was only poor to fair and clouds kept obscuring the view so it was difficult to determine which eyepiece performed better. So I decided to compare the eyepieces on some flowers that were located across the backyard. I inserted the 10mm Zeiss Abbe Orthoscopic first and carefully focused on the center of the flower and noted it had a couple of small bugs crawling on it. The 10mm Zeiss showed very fine detail, as I expected from these eyepieces. Then I inserted the 10mm TMB and after focusing could tell there was a difference between these two eyepieces right away. In the 10mm TMB the contrast was higher as the detail in the flower and bugs on it was sharper and better defined. Also, the colors were brighter and more pronounced in the 10mm TMB, indicating the light transmission was higher as well. I noted also the flowers had a more natural look to them.
I repeated the test with the other TMB and Zeiss, Pentax, and TV Plossl: the TMB 8mm Super Monocentric with TV 8mm Plossl and Pentax SMC 9mm Orthoscopic; TMB 6mm Super Monocentric with Zeiss 6mm Abbe Orthoscopic and Pentax SMC 7mm Orthoscopic; the TMB 5mm Super Monocentric with Zeiss 4mm Abbe Orthoscopic and Zeiss 6mm Abbe Orthoscopic; and the TMB 4mm Super Monocentric with Zeiss 4mm Abbe Orthoscopic, and results were the same: in each case the contrast, sharpness, light transmission were better in the TMB.
?楼主| 发表于 2008-3-24 21:36:08 | 只看该作者
Solar System Objects
Eyepiece comparisons for solar system objects were conducted only when the seeing conditions were good. If the seeing conditions were poor it was not possible to get a steady enough view to determine how the eyepieces performed.
A comparison was made between the Zeiss 10mm, 6mm, and 4mm with the TMB 10mm, 6mm, and 4mm using my friend's AP 92mm equipped with Baader white light solar filter. The TMB provided a sharper, brighter and contrastier images, with less light scatter around the edge of the Sun. This helped to bring out the detail better in the Sunspots, as well as in the facula.
A few days after I received the TMB eyepieces I observed the Moon with my friend using his 92mm and compared the Zeiss 10mm and Pentax 9mm with the TMB 10mm, as well as the TMB 8mm with the Pentax 9mm and 7mm, and the TV 8mm. The Moon during these tests was a couple of days past full and the Sunset terminator was near Mare Crisium and Palus Somnii. Due to the better contrast and sharpness in the TMB the elevation between the mare and mountainous wall surrounding it seemed higher and more 3 dimensional than in the other eyepieces. In addition the color of the lunar features appeared whiter, brighter, and much more natural in the TMB than we had seen before. For example the bright rays which radiate out from the crater Proculus and border Palus Somnii appeared whiter. Because of the very natural appearance of the Moon, we almost felt like we were looking at a NASA photograph taken from a spacecraft, or were orbiting the Moon in a spacecraft, rather than observing it through a telescope.
On another night when observing the Moon with the AP 5.1" a half dozen craterlets visible on the floor of Plato were resolved better in the TMB than the Zeiss and Pentax eyepieces, as were portions of the Alpine Valley rille.
When the Moon was at last quarter phase I compared the Zeiss 10mm with the TMB 10mm, as well as the TMB 8mm with the TV 8mm using the AP 7.1". At last quarter phase, the Apenninus Mountains stood out in bold relief and appeared white as they are illuminated by the setting Sun. There appeared to be many areas of debris that seem to have flowed down from the tops of these mountains. This included what appeared to be large boulders. While these features were visible in both the Zeiss and the TMB, the higher contrast, sharpness, and more natural appearance to the lunar features seen with the TMB gave the impression that these features were similar to what I have seen on the Earth, which was the first time I have felt this way when observing the Moon. Some of the isolated mountains on Mare Imbrium looked also more natural and were better defined in the TMB than the Zeiss, and Hadley Rille was easier to resolve in the TMB. When comparing the TMB 8mm with the TV 8mm the color appeared more off white or yellow in the TV, and it had lower contrast, as well as lower image brightness and sharpness than the TMB.
At crescent phase, the lower light scatter in the TMB made it easier to see faint stars near the earthlit portion of the Moon than in the Pentax.
Venus was observed in the western sky one evening with my friend's AP 92mm and we compared the TMB 8mm with the Pentax 7mm. We both felt that the planet appeared brighter, whiter, and the gibbous shape more sharply defined in the TMB than the Pentax. Also the sky background adjacent to Venus was darker in the TMB than in the Pentax, and the dusky appearance along the terminator was easier to see in the TMB than the Pentax.
Although Mars had its closest approach to Earth in August 2003 in nearly 60,000 years and attained a diameter of 25.11", due to its relatively low elevation at my observing location (around 30 degrees), my observations of Mars often were adversely affected by mediocre seeing. I actually had more periods of steady seeing when Mars was slightly smaller in September 1988 when it obtained a diameter of 23.81" and its elevation reached 46 degrees.
Still there were a few nights during the 2003 opposition when the seeing settled down and some good detail was observed. On these occasions the TMB had less light scatter, provided more natural looking and pronounced colors, and gave sharper and more detailed views than either the Zeiss or Pentax Orthoscopics. This included rifts in the South Polar Cap (SPC), as well as Lowell's melt band around the SPC. Also the TMB eyepieces showed Mare Hadriacum with a feathered or striated appearance to it. Atmospheric details were better defined in the TMB such as the limb clouds, the North Polar Hood clouds, and a small dust cloud in Hellas.
On one night of very good seeing Mare Erythraeum and Aurorae Sinus appeared mottled with many variations in tone, and I felt that for the first time I was accurately seeing and resolving its surface detail. Neither the Zeiss nor Pentax Orthoscopics provided the same amount of subtle detail, nor the sense that I was accurately resolving its surface features.
?楼主| 发表于 2008-3-24 21:36:34 | 只看该作者
Jupiter has a mix of high contrast and low contrast features which is a good test to see how well eyepieces perform for the planets. Examples of high contrast features include belts and zones such the North and South Equatorial Belts (NEB and SEB), and the Equatorial Zone (EZ). Low contrast features would include festoons, veil or shading in the zones, mottling in the polar regions, and the Equatorial Band (EB).
When observing Jupiter I noted that the TMB showed lower light scatter, higher contrast and sharpness, and a blacker sky background than the Zeiss and Pentax. In addition the colors of the belts and zones were brighter, more pronounced, and had a more natural appearance in the TMB. The importance of lower light scatter, blacker sky background, and better light transmission and contrast in an eyepiece designed for planetary observations became very apparent one night with steady seeing conditions while I was observing Jupiter with the AP 7.1". The TMB resolved detail better, including mottling in the North Polar Region, bays, ovals, and festoons along the NEB south, and a faint EB in a dusky EZ. This, in addition to the natural appearance of planet, reminded me of a view from a spacecraft, rather than through a telescope. It was the most realistic and natural view of Jupiter I have ever had.
Also during periods of steady seeing conditions and observing with the AP 7.1" and 5.1" the Moons of Jupiter appear as disks with subtle but noticeable differences in color. For example Ganymede is the largest and appears light-medium yellow, Callisto is the smallest and appeared light gray in color, and Io appears white/light yellow/light orange, while Europa appears white in color. In the TMB the disks are more sharply defined and the subtle colors are more pronounced.
Saturn is one of my favorite objects to observe, and I have been impressed by the amount of fine detail that the Zeiss and Pentax eyepieces have shown me in my telescopes. So I was curious if the TMB eyepieces would show me any additional detail. One of the first things I noticed when comparing the view through the Zeiss and Pentax with the TMB eyepieces was that there was less light scatter in the TMB, and that Saturn appeared whiter and brighter. In addition the globe in front of the rings appeared more 3 dimensional, perhaps because of the increased contrast and sharper image in the TMB. The colors of the planet were more pronounced and natural looking as well.
Using the TMB eyepieces I found it easier to see the atmospheric detail on Saturn than when using the Zeiss or Pentax. For example the Equatorial Zone, Equatorial Band, South Equatorial Belt, South Equatorial Belt Zone, South Tropical Zone, South Temperate Belt and Zone, South South Temperate Zone and Belt, and North Polar Region were easier to denote in the TMB. The results were more pronounced when comparing the 8mm TMB with the TV 8mm Plossl, as the colors in the TV were less saturated, more yellowish, and the overall sharpness and contrast was less detailed than in the 8mm TMB.
Detail in the ring system was easier to note in the TMB as well. This included the Encke Minima in the A-Ring, the globe of the planet visible through the Cassini Division, shading along the inner portion of the B-Ring and intensity Minima in the B-Ring, and the Crepe Ring.
Titan, which under steady conditions in the AP 7.1" appears resolved as a reddish-orange color disk, was more sharply defined in the TMB and the colors more pronounced. In addition faint moons near Saturn were easier to see in the TMB.
For all of these reasons, using the TMB eyepieces for my Saturn observations makes me feel like I am seeing the planet in a whole new way, despite the fact that I have been observing it for many years.
Deep Sky Objects, Double Stars, and Bright Stars
To see how well the TMB performed on different deep-sky objects (DSOs) a variety of objects were observed that are visible in the summer, fall, winter, and spring night time skies. This included supernova remnant M1; globular clusters M13 and M22; planetary nebulae M27 and M57; emission nebulae M17 and M42; diffuse nebula M78; spiral galaxies M31, M33, and M81; elliptical galaxies M32 and M110; irregular galaxy M82; open clusters M11 and M41; double stars including Alberio, the Double Double, Izar, and Rigel; and bright stars including Sirius and Vega. The limiting magnitude during most of the tests ranges from 5.0 to 5.4, and the seeing was good.
During my tests I noted that the sky background was darker in the TMB than the Zeiss and Pentax Orthoscopics or TV Plossls. This, in combination with the higher contrast, sharpness, and light transmission in the TMB, helps them to bring out the faintest detail visible in DSOs. The same held true for observing and splitting double stars.
?楼主| 发表于 2008-3-24 21:37:11 | 只看该作者
M1 - The internal structure and irregular shape of the Crab Nebula was better defined in the TMB than the Pentax eyepieces in my friend's AP 92mm. In addition a nearby double star was easier to split in the TMB.
M11 - The darker sky background, better definition, and tighter star images made it easier resolve the stars in this open cluster when using the TMB than the Zeiss or Pentax eyepieces in the AP 5.1".
M13 - The stars were resolved better at the core and around the edges in the TMB than the Zeiss or Pentax in the AP 7.1". It was even more pronounced when comparing the TMB 8mm and TV 8mm.
M17 - In the AP 5.1" the detail in the Swan Nebula, including the darker and lighter portions within the nebula, as well as faint nebula behind its neck and tail, was easier to see in the TMB than the Zeiss or Pentax eyepieces.
M22 - As with M13, M22 was also better resolved at the core and around the edges in the TMB than the Zeiss or Pentax eyepieces in the AP 5.1".
M27 - The hour glass shape of the Dumbbell Nebula, as well as the foot ball shaped extensions on each side, were easier to see in the AP 7.1" when using the TMB than in the Zeiss, as was the mottling within the nebula. The same was true for the fainter stars embedded within the nebula.
M31 - When observing the Andromeda Galaxy in the AP 5.1" the TMB eyepieces made it easier to see two dust lanes than the Zeiss or Pentax eyepieces. In addition detail in and around the core of M31, such as the dark nebulae off to the side of the nucleus, and NGC 206, a star cloud in the south end of the galaxy, were easier to denote in the TMB.
M32 - In the AP 5.1" the oval shape and starlike core were brighter and resolved better in the TMB than Zeiss or Pentax.
M33 - The TMB eyepieces showed more mottling in the central region of the Pinwheel Galaxy in the AP 5.1" than the Zeiss eyepieces, and the higher contrast of the TMB made it easier to see the spiral arms.
M41 - The TMB 8mm eyepiece did a better job resolving the stars in this cluster than the Pentax 7mm in my friend's AP 92mm, and the color of the red star near the center of this open cluster was more pronounced.
M42 - The Orion Nebula appeared brighter and showed more mottling and fine detail in the TMB than the Zeiss and Pentax in the AP 5.1" and 7.1". The star images appeared sharper and brighter as well, so the fifth and sixth star of the Trapezium were easier to denote. Also the light blue color of the Orion Nebula was easier to see in the TMB.
M57 - The Ring Nebula through the TMB eyepieces was brighter, better defined, and showed more variation in tone than the Zeiss eyepieces in the AP 7.1". This was particularly true at the rims of the nebula at each end, which appeared more elongated. In addition the central region of M57 appeared brighter, and nearby stars were easier to resolve.
M78 - The two 10th magnitude stars in this nebula and the somewhat mottled and elongated appearance to it appeared brighter in TMB than the Pentax eyepieces in my friend's AP 92mm.
M81 and M82 - In my friend's AP 92mm the oval shape of M81 was easier to see in the TMB than the Pentax, as were the dust lanes between the center of the galaxy and the arms. M82's elongated spindle shape that seemed to curve up at one end was defined better in the TMB eyepieces than the Pentax.
M110 - In the AP 5.1" it was easier to denote the stellar core of M110 with its brighter central area that faded out to a less bright outer area in the TMB than in the Zeiss or Pentax eyepieces.
Albireo - This is one of my favorite double stars and the TMB provided the most beautiful view of this double star I have ever had. The reason they performed better than the Zeiss was a combination of higher contrast, sharper star images, the colors being brighter and more pronounced, and darker sky background in the AP 5.1". After completing the eyepiece comparisons I observed Alberio for another hour and just enjoyed the view through all of the TMB eyepieces including the 10mm, 8mm, 6mm, 5mm and 4mm.
The Double Double - These double stars were easier to split in the TMB than the Zeiss, showing cleaner and brighter star images as well as a darker sky background between the stars in the AP 7.1".
Izar - The primary star of this double star is a light yellow or golden color, while its smaller companion star is light blue. When comparing the view through the AP 5.1" the colors were brighter, more pronounced, and it was easier to split in the TMB than the Pentax eyepieces.
Rigel - Although this double star is not difficult to split (separation of 9.5") the difference in magnitude between the primary and secondary stars (6.5) can make it more challenging to see the dimmer secondary. The lower light scatter and darker sky background in the TMB made it easier to see the companion star than in the Pentax eyepieces in my friend's AP 92mm.
Sirius - The sky background around Sirius appeared darker in the TMB than the Pentax in my friend's AP 92mm, and there was less light scatter, so it was easier to see fainter nearby stars. Also Sirius appeared whiter in the TMB.
Vega - As with Sirius, the sky background around Vega appeared darker in the TMB in the AP 7.1", and there was less light scatter, so it was easier to see fainter nearby stars. Also Vega appeared whiter in the TMB.
Overall I have been very impressed by these eyepieces. They bring a new level of performance to my observing, in many cases showing me detail I have never seen before in over 30 years of observing. I find that I want to go back and observe celestial objects I have observed many times before in order to see what new detail they will show me. While I have seen improvements in other eyepieces over the years, the combination of the better sharpness, light transmission and contrast, as well as lower light scatter and a darker sky background in the TMB provide a new way of observing celestial objects. In addition I did not find their smaller field of view to be an issue when I used them with my telescopes on homemade Dobsonian-style alt-az mounts.
I think other observers will find these eyepieces useful as well. For example, solar, lunar, and planetary observers will find these eyepieces help to bring out finer detail, as well as providing a more natural view of these objects. Double star observers will find these eyepieces make it easier to split double stars, in particular ones that have a brighter primary star, as well as enhance the colors of the stars. Deep-sky observers will find them useful in bringing out the faintest detail visible in DSOs.
Many years ago Al Nagler revolutionized wide field deep sky eyepiece designs when he introduced the Nagler and Panoptic eyepieces. In many ways I feel Thomas Back has done the same thing by revolutionizing narrow field planetary eyepieces with his TMB Super Monocentrics
?楼主| 发表于 2008-3-24 21:49:37 | 只看该作者


Review of Eyepieces for the Planets
Zeiss Abbe Orthoscopics, Pentax SMC Orthoscopics, TeleVue Plossls, and University Optics Orthoscopics compared
I first began observing back in the early 1970's, and since then have used a variety of eyepeices to see which ones work best for observing the planets. Here is a review of some of the eyepeices I have tried.
One comparison was between the Zeiss Abbe Orthoscopics (1.25"), Pentax SMC Orthoscopics (0.965"), TeleVue (TV) Plossls, and University Optics (UO) Orthoscopics. I did not have duplicate eyepieces of the same focal length, so tried to look for overall general performance characteristics. My tests were conducted during several observing sessions using my Astro-Physics (AP) 180mm f/9 EDT refractor using a MaxBright diagonal on a variety of objects including the moon, Jupiter and Saturn, double stars, bright stars, and deep-sky objects. The seeing and transparency conditions were about the same during these observing sessions. The eyepieces I used for this comparison included an 11mm TV (147x), 10mm Zeiss (162x), 9mm UO (180x), 8mm TV (203x), 7mm Pentax (231x), and 6mm Zeiss (270x). Since there was a relatively wide range of magnifications I broke the eyepiece comparisons into six groups with some overlap: the 11mm TV with the 10mm Zeiss; the 10mm Zeiss with the 9mm UO; the 9mm UO with the 8mm TV; 8mm TV and 7mm Pentax; and the 7mm Pentax, and 6mm Zeiss.
I will start with the UO Orthoscopics (Orthos) and TV Plossls first. In general, I found the performance of these eyepieces to be fairly close. The main differences I noted was that the light transmission in the UO Ortho seemed a bit better then in the TV Plossl. For example, I was able to see fainter stars in the Double Cluster in the UO then in the TV. Also, there appeared to be a tad less scattered light around Jupiter in the UO then in the TV. The contrast on the moon appeared to be the same in both eyepieces. Whitish colored areas on Saturn and in its rings appeared a bit more off-white in the TV then in the UO.
When comparing the Zeiss to either the UO or TV, the Zeiss had noticeably better light transmission, contrast, less light scatter around bright objects, and better overall sharpness. The other differences I noted between the Zeiss and Pentax vs. the UO and TV was that the planetary colors seem more accurate. This may be somewhat subjective on my part however.
I felt that the Pentax and Zeiss were very close to each other in overall performance. It is my understanding that the Zeiss eyepieces were designed to work well with their APQ refractors, which are f/8. So if you are using them with a telescope with a focal ratio of f/8 or longer the stars are sharp right to the edge of the field of view.
I feel the UO and TV offer a lot of performance for the money however, so would not hesitate to recommend them.
Clave Plossls compared with TeleVue Plossls, Brandon Orthoscopics, and Aus Jena Orthoscopics
I first began using TV Plossls back in the early 1980's after they were introduced and Richard Berry said that they were the sharpest he ever used. They replaced the Meade Research Grade Orthoscopics I had been using for a few years. Prior to this, I had used the Huygenian, Ramsden, Achromatic Ramsden, and Kellner eyepieces that had come with the small achromatic refractors and 4-1/4" and 6" reflectors that I purchased.
Then in the mid-1980's a friend of mine recommended that I try Clave Plossls. When I compared the 17mm TV with the 16mm Clave using a 4" f/6 AP and 6" f/9 AP refractors the Clave seemed to have better sharpness and contrast than the TV, and the TV showed more scattered than the Clave. For example, when observing Sirius the TV showed more scattered light around it, so it made it harder to see fainter nearby stars than in the Clave. The same was true when observing Mars, where I could see more background stars in the Clave than the TV. Also, the Clave showed higher contrast and sharper details on the moon, planets, stars, and deep-sky objects than the TV. The TV had a slightly wider field of view, reported to be 50 degrees while the Clave were reported to be 48 degrees, and the TV had slightly better edge correction than the Clave.
Recently I did some additional comparisons between an 8mm Clave Plossl and 8mm TV Plossl using the 180mm AP. Note that the Clave was manufactured back in the 1970's, while the TV was of recent manufacture (late 1990's). I mention this because there is a general impression that the 1-1/4" Clave's manufactured in the 1970's and 1980's were of higher quality then those manufactured after Mr. Clave sold the business in the early 1990's. The objects I compared the eyepieces on included the moon, Jupiter, and deep-sky objects. Overall, although similar in performance, I would give the edge to the TV, as it had less scatter, darker sky background, higher contrast, and better light transmission then the Clave. Note that this is different than when I compared Clave Plossls manufactured in the 1980s with TV Plossls manufactured in the 1980's.
From the mid-1980's until the mid-1990's the Clave were my standard eyepiece of choice for the planets, moon, and deep-sky objects. I purchased a 6mm, 8mm, 10mm, 12mm, 16mm, and for low power use a 2" 35mm and 2" 40mm. It was during this time that I purchased and tested them with other eyepieces, including Brandon Orthoscopics, Aus Jena Orthoscopics.
I compared a 24mm, 16mm, and 12mm Brandon's with a 25mm, 16mm, and 12mm Clave on the moon, planets, deep-sky objects and stars using the a 4" f/6 AP and 6" f/9 AP refractors. The Clave had a slightly larger field of view, 48 degrees, than the Brandon's which was 45 degrees. However the Brandon's came standard with eyecups which made it easy to "tuck" my eye into to see the entire field of view. Overall, the Brandon's showed slightly higher contrast than the Clave, while the Clave had slightly higher image brightness.
In 1989 I compared the 16mm, 12mm, and 10mm Clave with the 16mm, 12.5mm, and 10mm Aus Jena Abbe Orthoscopic eyepieces which had 0.965" barrels. Note that the Aus Jena Abbe Orthoscopic 0.965" eyepieces were manufactured in the East Germany (before the Berlin wall came down and East and West Germany were reunited) and were imported into the United States. They are not the same as the Zeiss Abbe Orthoscopic 1-1/4" eyepieces that were imported from Germany in the 1990's into the United States by Astro-Physics.
When observing the Clave and Aus Jena eyepieces on the Saturn, Vega, the moon, and deep-sky objects, they eyepieces were similar in performance. The Clave had slightly better image brightness, while the Aus Jena had slightly less light scatter. The Clave had a larger field of view at 48 degrees, while the Aus Jena had a 42 degree field of view and had better edge correction.
Clave Plossls compared with TeleVue 9mm Nagler
In 1986 I compared the Clave Plossls with a TV Nagler 9mm (the original Nagler 9mm Type 1) using the 4" f/6 AP and 6" f/9 AP refractors. The 9mm Nagler had an impressive 82 degree field of view, and had better edge correction than the Clave Plossls. So it was possible to view the entire disk of the moon, and large portions of deep-sky objects like M42 and M31. However, the Clave had better light transmission and contrast which made it easier to see fine low contrast details on the planets and in deep-sky objects. I have tried some of the newer Naglers, including the 12mm Type 4 and 16mm Type 5, and these show much better light transmission and contrast than the original Naglers, and I often use them when observing and making sketches of deep-sky objects. For the planets I prefer to use Orthoscopic and Plossl eyepieces.
Clave Plossls compared with Zeiss Abbe Orthoscopics and Pentax SMC Orthoscopics
In 1996 a friend of mine recommended that I try Zeiss Abbe Orthoscopics and Pentax SMC Orthoscopics, and so I compared them with my Clave Plossls using the AP 180mm. On the planets, moon, deep-sky objects, and stars, Zeiss Abbe Orthoscopics and Pentax SMC Orthoscopics showed better light transmission, contrast, overall sharpness, less scatter, and better edge correction than the Clave Plossls.
Here is a comparison between the Zeiss Abbe Orthoscopics and Pentax SMC Orthoscopics with the TMB Super Monocentric Eyepieces.
University Optics Orthoscopics compared with TeleVue Radians
I had the opportunity to compare a 12.5mm UO Ortho with a 12mm TV Radian with the AP 180mm. The Radian had a clear advantage in terms of FOV and comfortable (20mm) eye relief. With fewer elements the UO had better light transmission, contrast, and resolved stars better across the core of M13 and showed fainter detail in M57.

[ 本帖最后由 siqingtan 于 2008-3-24 21:56 编辑 ]
发表于 2008-3-25 08:16:17 | 只看该作者
发表于 2008-3-25 08:31:33 | 只看该作者
发表于 2008-3-25 09:45:11 | 只看该作者
?楼主| 发表于 2008-3-25 09:54:58 | 只看该作者
发表于 2008-3-25 10:07:14 | 只看该作者
发表于 2008-3-25 15:39:39 | 只看该作者
原帖由 siqingtan 于 2008-3-24 21:49 发表
Review of Eyepieces for the Planets
Zeiss Abbe Orthoscopics, Pentax SMC Orthoscopics, TeleVue Plossls, and University Optics Orthoscopics compared
I first began observing back in the early 1970's,??...

?楼主| 发表于 2008-3-25 15:51:52 | 只看该作者
是Eric Jamison写的
发表于 2008-3-25 16:19:14 | 只看该作者
原帖由 siqingtan 于 2008-3-25 15:51 发表
是Eric Jamison写的

原来是他, 我刚刚搜了一下, 发现我读过他不少review。 感觉他偶尔有点主观, 但总的来说比较中肯。 所以他的文章可信度还是较高的。
发表于 2008-3-26 09:51:54 | 只看该作者
发表于 2015-5-9 12:08:24 | 只看该作者
TMB SUPER MONO 5MM手上有一个,和TV ZOOM 3-6看不出有什么实质性的差别,
发表于 2015-5-10 01:13:44 | 只看该作者
望远控 发表于 2015-5-8 20:08
TMB SUPER MONO 5MM手上有一个,和TV ZOOM 3-6看不出有什么实质性的差别,

背景的干净程度, 漫反射控制, 对比度等等, SuperMono在稍好的条件下就有明显优势。
发表于 2015-5-16 23:55:12 | 只看该作者
wbhifi 发表于 2015-5-10 01:13
背景的干净程度, 漫反射控制, 对比度等等, SuperMono在稍好的条件下就有明显优势。



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