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NP127is - f5.2 Nagler-Petzval Imaging System Apochromat Refractor (5.0 inch aperture)
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 Above: Typical TeleVue Petzval telescope optical arrangement; 1. air spaced doublet objective, 2. mounting collar, 3. doublet lens, 4. focuser. Options shown include: 5. "Everbrite" 2 inch mirror diagonal, 6. 2" to 1.25" reducer, 7. eyepiece (optional) |
In prior TeleVue telescopes one could in theory remove the rear doublet lens and use the telescope with the objective lens alone in place. But the NP101 and NP127 are a departure from traditional TeleVue Petzval derivatives. Incorporating TeleVue's best air-spaced special dispersion doublet lens with what appears to be a simple doublet telecompressor/field flattener, the NP127 provides flat field wide angle views and the oversize rear elements of the NP127is provide coverage beyond that required solely for use with eyepieces. This is a complicated design where neither lens group can function independently without the other to form a good quality image.
Accepting 1-1/4 or 2 inch accessories including the highly regarded TeleVue Radian, Nagler and Panoptic eyepieces, the NP127is provides visual magnifications as low as 12X and a tack sharp field of view of as wide as 4 degrees are possible! A multi layer anti reflection coating process of the lenses, and on all the TeleVue eyepieces prevents light reflection off the surface of, or between the lenses. The result is a very fast, wide and flat-field system so well corrected that panoramic nature or star and planetary images are breathtaking. A collapsing lens shade aids portability. Its' uses include birding, CCD or video imaging, and film photography as well as visual and astrometric astronomy.
The TeleVue NP101 and the NP127 series telescopes are the first large TeleVue Apochromatic refractors which Company Seven found to be truly competitive if not superior in optical and mechanical performance to the best Apos ever made. They occupy a unique niche in the telescope inventory since no other telescopes exactly duplicate their out of the box versatility and ease of use. These telescopes provide false color-free, sharp, clear and high contrast images. And since the best apochromatic refractors are among the most difficult and costly in raw materials to make consistently well, these Apo refracting telescope will cost notably more than competing designs - but the waiting lists and high resale values testify to the confidence that the astronomy community has in telescopes such as these.
Left: TeleVue NP127is 2010 model telescope front cell and objective lens, with its fully machined lens cover to the side (43,032 bytes).
Click on image to see enlarged view (239,831 bytes).
The system's air to glass surfaces have a multilayer antireflection coatings that improves overall light transmission across the visual wavelengths and from 400nm to well beyond 700nm. The coatings used on the NP127is telescope are engineered to match the characteristics of each glass type and curve radii. This process improves color rendition, achieves a dramatic increase in image contrast and actual light transmission, with a corresponding reduction in flare which might otherwise originate by internal reflections. Overall the complete four lens system provides about about 300 times the light gathering power of the unaided human eye - about the same as typical 5 inch doublet systems. The 2010 version NP127is incorporates a stainless steel objective lens cell, this provides improved thermal stability even in extreme climates. On most nights, the settling down time for the optics will be the order of minutes; from room temperature to freezing it rarely will require more than 45 minutes to an hour for the optical tube assembly to acclimate.
The lenses are so well figured that the consistency between telescopes is quite good, and each is capable of operating at very high magnification cleanly (even with optional "Barlow" or "Powermate" lenses). This telescope crosses that threshold necessary to routinely obtain meaningful views of the planets, showing several bands and their shades of color (from creamy whites to beige, tan, browns) on Jupiter - observe the four largest moons of Jupiter and their shadows cast on the surface as distinct discs as they transit across the planet at times eclipsing one another! Study the Cassini division and banding on Saturn, the polar cap and dark markings on a fiery red Mars. With an eyepiece that shows 1/2 degree field or so (such as a 5 mm "Nagler" or 6mm "Radian") take a walk on a apparently three dimensional Moon, resolving objects as small as 3.5 km in diameter. Or follow the lunar terminator throughout the phases; optional neutral density filters are offered by Company Seven to attenuate brightness and make observing more comfortable.
With an optional white light solar filter (such as our Baader AstroSolar film) observe Faculae and Sunspots on the Sun! With our optional Hydrogen Alpha filters (either the DayStar ATM or University series) observe Faculae, Sunspots, the peach-fuzz like photosphere surrounding the Sun, and the sheer curtain-like Prominences as they erupt from the Sun out into the blackness of space!
A matched wide angle ocular reveals the NP127is's extraordinary wide field of view capability, and can easily reveal the entire Messier Catalog of deep sky wonders. It is also just as well employed for panoramic viewing of a seashore or countryside. Imagine a telescope that at a dark sky site has the combination of resolving power and field of view to sweep the Milky Way, see the Double Cluster in Perseus (NGC-869) in their entirety, find the Andromeda galaxy (M-31) and see it's ellipsoid shape and several dust lanes, and with no doubt see the distinct forms of large Nebulae such as the Veil and North American Nebulae! With a wide angle eyepiece the TeleVue NP127 can reveal all three stars of Orion's belt, closer in it reveals the jewel like stars of the Trapezium - a birthplace of stars, with a sweeping wisps of greenish gas clouds surrounding it.
Studied under a higher magnification M13 (the "Messier" catalog Hercules star cluster) takes on a three dimensional salt and pepper appearance even from suburban skies on a clear night. By the time one finds a large enough aperture catadioptric, reflecting, or achromatic refractor to see similar detail then one can only see a fraction of their area due to the relatively high focal length of these competing telescopes; with other telescopes it would be something like trying to observe the night sky through a straw! But observing through a fast Apo is an experience where you are more often able to view the entire painting, and not just some small portion of it, and with the light gathering power of this 5 inch Apo, on attains the real deep sky experience.
In fact, one of the finest advertisements ever published for a multi purpose telescope concept is the book Deep-Sky Companions: The Messier Objects where the author Stephen O'Meara sought to keep the drawings relevant to the amateur. To produce the highly detailed drawings of these celestial objects Stephen chose to observe with the second generation TeleVue "Genesis" telescope (4" aperture, 500mm f5) which as glass technologies advanced has since been replaced by the improved TeleVue apochromatic telescopes. This book has become one of our best advertisements for the versatile, readily transportable fast 4 inch (10cm) refracting telescopes. Similarly to keep things simple, and relate as much as possible to the average amateur observer Stephen chose to use the telescope on the simple but sturdy TeleVue "Gibraltar" alt-azimuth mount with Ash Wood tripod. He equipped the telescope with only a modest selection of accessories: TeleVue 22mm "Panoptic" eyepiece (providing 23X, 2.85 Degrees Actual Field of View), a original 7mm Nagler eyepiece (71X, 1.08 AFOV), and a TeleVue Barlow lens to increase the magnification by 1.8X. In fact Stephen O'Meara recently commented "the TeleVue NP101 would now be my telescope of choice". Read that book and then consider the 60 per cent improvement in light gathering power that the aperture advantage alone of the NP127 should provide!
The NP127 telescopes compare favorably against many telescopes in field of view but in fairness the cost of these NP127's, like most other serious Apo's (equipped with either an optional Alt-Az or Equatorial mount), is positioned at a higher level than most amateur telescopes. As a practical matter for some applications in astronomy the nominal match of the NP127 telescope exit pupil to an average dark adapted human eye will be obtained at magnifications of between 18X and 25X. The best performance and viewing comfort will be obtained at all magnifications if a wise choice of good quality oculars is made however since the NP127 telescopes incorporate a field flattening component then it is technically compatible with several of the simpler eyepiece designs. Most of our NP127 customer employ an optional good quality Barlow lens or a TeleVue "Powermate" amplifying (negative) lens, or optional wide angle "Nagler" or long eye relief TeleVue "Radian" ocular will usually be put into use to attain the highest usable magnifications which are necessary for observing small bright objects including planets, and close double stars. But we can think of little else that could be more awe-inspiring than wading into a star cluster or nebula with the NP127 using a TeleVue 13mm Ethos eyepiece viewing 2 Degrees of sky at 51X!
For film or digital photography the NP127is telescope (with our optional camera adapter) becomes a super sharp 660 mm f5.2 ultra telephoto lens, showing about 3.7 degrees across the diagonal of a 35mm camera film plane or on the larger sensors employed on some of our SBIG imaging systems. The focuser provides a clear aperture of 2.4 inches, suitable for use with digital camera systems (integrating CCD/CMOS, DSLR, etc.) with diagonal formats up to 52mm. For video camera imaging operations the telescope at prime focus can show an area about 0.7 degree across the diagonal of a common 2/3 inch format detector. Optional techniques and hardware permit imaging of galaxies, nebulae, the planets, or of terrestrial targets including wildlife.
The NP127is is well at home on any of a number of suitable optional German Equatorial mounts, but our favorites include:
This is a telescope one may not outgrow, but since most of the accessories that one would buy for this telescope are upwardly compatible with any larger telescope that one is likely to buy at Company Seven one will not feel trapped by the cost of accessories for the second telescope. It has been argued by many experienced observers that while no one telescope can do it all, the Apo refractor is most versatile. And it can be complemented by a large 18 to 22 inch aperture Dobsonian telescope such as those we offer by AstroSystems.
The telescope objective (front) lens cell, retracting dew shield, lens cover, focuser housing, 2 inch mounting collar and other fittings are of fully CNC milled aluminum construction, entirely black anodized in a deep lustrous finish that is new for the 2010 model NP127is. The barrel is powder coated in a textured neutral Ivory; the powder coat feels like a thick textured smooth plastic covering which is quite comfortable to manage even in extreme cold or damp climates. The interior of the optical tube assembly is lined with an antireflective covering unique to TeleVue telescopes, which is then finished with anti reflective black paint. Aesthetically this is a good looking instrument that inspires confidence and pride of ownership - it is certainly the best constructed and appointed telescope ever to bear the TeleVue trademark, and is one of the top performing Apos of this aperture class made today.
The NP127is has a fully machined aluminum front cell to house the objective lens. The objective lens is permanently aligned to the barrel as is the focuser assembly. Unless subjected to gross abuse this telescope will provide many lifetimes of service with no need for any other than cleaning of the front surface of the objective lens using common camera lens cleaning techniques. Its construction is extremely rugged to allow it to withstand all the handling that is typical of airline travel. However, some caution should be practiced not to damage the focuser pinion of any telescope; our experience with this focuser is that with routine handling this will not happen and in its hard shell case is routinely transportable. The NP127is does incorporate a retracting Dew Shield/Lens Shade.
Right: TeleVue NP127is 2010 model telescope front cell with its fully machined lens cover threaded on (117,894 bytes).
Click on image to see enlarged view (313,010 bytes).
However, we also see the 5/8 inch protruding hand knob as something of a potential obstacle; for our taste we'd prefer to have more foam padding between telescope and wall of the carrying case. This knob increases the risk of damage to the front of the telescope by that distance. The knob adds needless length to a telescope that within a nicely fitted padded bag might otherwise be slipped onto an airplane for travel; the NP127is would be down to 32-9/16 inches long without that knob.
Revised 2010 Focuser: The TeleVue focusers continue to be among the smoothest and easiest to operate focusers in production. This focuser is a rack and pinion design with a tension/lock screws which helps to lock focus for uses including photography. With its larger diameter draw-tube, the NP127is can accept either the 2.4 to 2 inch diameter accessory holder (provided and as shown in the images), or it can accept a variety of fittings to accommodate film and CCD imaging cameras. A basic Imaging Adapter is provided with the telescope and is stored in a compartment in the lid. This adapter is simply a precisely machined metal ring that is threaded to accept any one of a number of the fittings made by TeleVue and third parties; this ring attaches onto the draw-tube of the focuser in place of the 2 inch accessory holder. Either adapter is secured by means of the four set screws arranged so that the observer may find at least one lock convenient to reach regardless of where the telescope is pointed. The four screws also provide a measure of safe redundancy and distributes the pressure around the clamp making it a bit easier to attain a grip on heavier accessories.
The 1-1/2 inch diameter machined aluminum hand knob resembles the brushed aluminum mag wheels available for radio control model cars. The knob hand grips are rubber covered to facilitate operation in all extremes; even when wearing gloves all the controls on the telescope are easy to manipulate. The set screw has an easy to grip knurled head, this permits one to adjust resistance of the focuser to its draw tube thereby compensating for heavy loads that might otherwise cause an unintended shift of focus.
The aspect that differentiates the NP127is of 2010 most from the prior two generations of NP127 is the new precision focuser with dual speed gearing. The goal of this change is to:
With the introduction of the original NP127is TeleVue had engineered their own dual speed geared focus control mechanism, marketed as the Focusmate™. Focusmate™ was the first component of a comprehensive focus solution devised by TeleVue that includes choices for local and remote display of focus position, local and remote control of focus, and integration with TeleVue's own digital encoders and software for display locally or remotely of position. This begins with digital focus position readout by either 10 Micron Resolution kit or 1 Micron Resolution kit. And your choices continue with the Focusmaster™ module (as of this date this is still in development for the new 2010 model NP127is) and choice of TVFocus, or TVFocusPlus, or third party computer software. No other telescope maker provides their customer with so many choices.
The prior versions of this were an ungainly looking contraption that seems to take up way too much space hanging off the side of the telescope for our sense of aesthetics, and we had concerns about its vulnerability too. But in fact it worked, it works very smoothly to provide both coarse and fine focus with a reduction ratio of 6:1 (six turns per revolution), and is easier to turn and smoother in its motion than some other devices we've seen. As long as you do not run into it in the dark then the original Focusmate™ is reliable. For 2010, the focuser is improved with a new 10:1 (ten turns per revolution) focuser pinion assembly made for TeleVue by Starlight Instruments. The focus control dials do not protrude anywhere near as far as the original Focusmate™:. Just looking at the 2010 focuser inspires confidence.
The Starlight Instruments focuser is provided with the telescope attached with the dual speed geared control knob at the right side of the telescope. It is a simple matter to remove and install the Focusmate so that the control is on the left side, the case is cut for this to be arrange for either the right or left side. It is also possible to add the other components of the system to this but some change of the telescope orientation in the case and some cutting of foam may be necessary.
 TeleVue NP127is Focuser with 2 inch accessory holder, and Focusmate geared focus drive assembly. |
 TeleVue NP127is Focuser showing 127is standard knob on the left side as delivered. This can be reversed L-R for user's preference. |
 TeleVue NP127is Focuser view of newly redesigned Pinion Block. Drawtube has been withdrawn slightly. C7 QC label at bottom of focuser |
For comparisons, the focuser of the NP127is telescopes have 1.44X the clear area of the standard Televue 2 inch focuser as is provided with the original NP127 telescope. The new 2010 model 2.4 inch focuser is much more rigid than the 2 inch focuser provided with the original NP127 telescope and so it can handle the increasing weight of CCD cameras and their accessories.
The focuser of the NP127is also has slightly more focus travel so that it can accommodate a wider range of visual and imaging accessories.
Left: TeleVue's original model NP127 telescope focuser. Shown with draw tube fully retracted, note the 2" diameter no mar clamp lock mechanism (51,070 bytes bytes).
Click on image to see enlarged view (133,406 bytes).
This focuser is particularly beneficial to those who entertain CCD or film imaging with the heavier cameras; this design was tested so far with loads including an Apogee U9000 and the SBIG STL or STX series CCD camera which approach 5 lbs. (2.3 kg). The greaseless draw tube arrangement of the NP127is is more sophisticated in its machined arrangement, so that it has fewer bolt on parts to work loose. There is a clamp ring within the focuser body surrounding the draw tube, this provides uniform and more secure tension with less image shift applied by either of two set screws on the focuser housing drawing in to applying pressure onto an internal pad. The end ring is incorporated into the machined draw tube so there is no longer any way the payload can tilt at the end of the draw tube, and this arrangement incorporates a non-marring clamping mechanism to hold the various adapters. For convenience and safety the NP127is focuser has four clamp knobs on the draw tube accessory clamp provided so that the observer may find at least one lock convenient to reach regardless of where the telescope is pointed. We measured the focus travel distance of this 2010 model focuser draw tube as 2.4 inches (61.27 mm), about 10 mm greater than that of the original NP127.
Since the is series telescopes are geared for CCD imaging with larger formats CCD systems, and since the plane of a CCD may not perfectly parallel to the optical axis of the telescope across the focuser of the NP127 makes the provision to tilt it and bring the attached CCD into a more perfect alignment. We know of no other production telescope that has this mechanism. The process if it is ever needed would be best performed with the CCD camera attached in its desired rotational configuration (rotating the camera on the focuser may change the solution so one needs to be able to rotate the optical tube with the CCD to change framing), with the work performed in a clean controlled environment on a suitable test target. The process involves adjusting the "push pull" focuser bolts at the end of the draw-tube. This must be performed meticulously and while evaluating the changes to the image. Once the best focus is attained then the focuser is locked in place. And remember if a CCD camera necessitates a focuser tilt, then upon changing to another camera there will likely be a need to adjust the focuser back to its original configuration or repeat the process. If the CCD is notably out of alignment in its housing then Company Seven's advice is return the CCD camera for exchange.
Focus Control: the NP127 optical tube is machined mostly of aluminum and the lenses are of glass, so temperature changes will alter focus over time. While most people taking relatively short exposures will do well with the standard focuser, it is still not a good idea to touch a telescope to adjust focus when imaging. Company Seven recommends our customers who attempt long exposures, or seek the convenience of remote (not touching the telescope) control for focus, should employ a temperature compensating robotic focuser such as our Technical Innovations 'Robo Focus' or the Micro Touch motorized focusing kit. Either is a user retrofit able set including motor with hand held controller/interface that permits the fine or rapid control of focus either by local manual input (by pressing the 'In' or 'Out' buttons), or by electronic/automated remote control with a computer via USB or wireless:
The Micro Touch set includes a compact hand keypad that with a backlit LCD screen that presents a digital readout of focus position, as well as information used for programming the temperature compensation function. The LCD display backlight can be turned on or off by the user. This system can be controlled by a broad selection of optional astronomy software including MaximDL/CCD, and CCDSoft. The set is provided (at no extra cost) with the popular FocusMax software, and with the MicroTouch software, and with the required USB2 Drivers, all on an installation CD. These software applications operate on a Windows PC platform, and can be set up to automatically focus the telescope for imaging controlled by a CCD system, even compensating automatically for changes of temperature! This is ASCOM compliant. The system requires a 12 volt AC or DC power supply.
The set can be provided configured for wireless control depending on your choice of interface (PC, iPad, etc.) and protocol (usually 'Blue Tooth'). This is an option available to our customers that has only recently completed development and will be available sometime this Summer or early Fall 2011. The user can set the WL function to OFF then operate the set by the provided Keypad Control.
The set can be added to most Feather Touch equipped telescopes (Astro-Physics, TeleVue, etc.) and so you need only master one user interface. Company Seven will check out any MKIT prior to sending it, but we do not recommend attaching it to the telescope for delivery within the standard carrying case provided by the factory. We can however configure a custom ATA case to fit the NP127is, with space for the Micro Touch motor.
Carrying Case: Also included with the NP127is telescope is a die cut, foam lined hard shell carrying case with latch closures. This very lightweight formed ABS case has and compartment in the lid with a hinged door revealing extra space to accommodate the camera or visual adapter. The attraction of the case is its compact, non marring form (rounded plastic corners do not punch through car seat coverings), and its light weight. However, this is also its Achilles Heel: this case is NOT an Airline Transport Association (ATA) approved shipping case, and one would be foolish to trust their $7,000 investment in this case alone in any adverse environment.
Right: NP127is Carrying Case has dual handles, side by side (81,225 bytes).
Click on image to see enlarged view (258,164 bytes).
The carrying case is similar to that provided with TeleVue 4 inch refractors and with the NP127. But the case for the NP127is telescopes is given away by the two carrying handles installed side by side near the middle of the case. These handles reduce the chances of a sole handle giving way, and it also reduces the chances of accidentally dropping the telescope out if the latches are accidentally left unfastened.
At 38-½ inches in length the case will fit technically into the overhead storage area of most commercial aircraft (one exception being the L-1011) however, many airlines will not permit such an 'oversize' package on board. Even if they do you will not be too popular with fellow passengers when you take up an entire overhead space, and so you might ask a Flight Attendant to store the telescope for you - possibly in the garment bag storage area. Company Seven has made durable, custom tailored, padded form fitted carrying bag for customers who bought their NP127 from us. This lightweight padded bag zips to fully enclose the TV127is in a compact form, with its carrying strap a number of our customers carry the 34 inch long cylindrical pouch with telescope onto the aircraft where they are off to enjoy remote skies with 5 inches of Apo! Some extra care must be taken to protect (if not remove) the Focusmate™ from impact since this is not a rigid case.
The telescope in its standard hard shell case is well padded and then packaged for delivery within one box, and then this is placed into another box. You should consider the practicality of simply shipping telescopes (and mounts) such as this ahead by a priority air service (FedEx, UPS, U.S. Mail, etc.) if you are concerned about cutting down the number of bags you can carry on or check in. Furthermore, shipping the telescope could reduce risks of loss or damage in shipment, and inconvenience and risks of managing bags through airport terminals. If you wish to travel with your NP127 then ask Company Seven about out wonderfully engineered Airline Transport Association transport (for check-in) and shipping cases for telescopes, mounts, and accessories.
Attachment Hardware: The NP127is is ordered 'ala Carte', this is to say that nothing much beside the OTA and the case are provided. This gives the end user the choice of how they prefer to install the telescope and what they wish to add on to the telescope: one does not pay for what one may not use. Company Seven offers several third party and custom options for customers who buy their NP127is from us, and you may contact us to discuss these choices and applications.
TeleVue offers a set of optional hardware consisting of two (one pair) conventional style clamp-on mounting rings. Each is a circular split ring machined of aluminum and black anodized with a lining of fabric. The ring halves are bolted together by means of a hex head bolt on one side, while on the other side is a manual tension adjustment knob. This arrangement permits one to adjust the grip of the rings on the barrel with no tools so that the telescope may be easily moved back and forth to compensate for changes of accessory loads that may affect the balance of the telescope on a mount. A machined aluminum bar is bolted on spanning the two mounting rings across the top to add extra rigidity, this does not seem to be necessary but no astronomer ever complained about too rigid a support system. At the 10:30 and 1:30 o'clock positions on the top of the collar there is a dovetail platform to accommodate a variety of TeleVue options including the "Starbeam" sight, or a
Right: TeleVue NP127 telescope optional MRS-5000 Mounting Ring set with stiffening bar (58,808 bytes).
A machined aluminum mounting plate is provided installed at the 6 o'clock position on the mounting rings. The rectangular plate is provided with two 1/4 inch 20 tpi stainless steel studs installed with wing nuts which makes the NP127 ready to slip onto the TeleVue alt azimuth mounts. The mounting plate features several other tapped and threaded holes to facilitate installation of the NP127 onto other mounts or plates.
This ring and bar set is a good arrangement for those using the telescope for applications including visual, or light duty astrophotography or CCD imaging which demand extremely rigid support of the telescope. However, for those of our customers interested in employing heavier piggyback loads atop the NP127 (guide telescopes, large finder, etc.), then Company Seven can provide optional alternative rings and mounting plate hardware.
Mirror Diagonal: If you intend to use the NP127is for visual uses, then it will be necessary to furnish the telescope with an optional mirror diagonal. One good choice would be the TeleVue 90 degree 2 inch diameter "Everbrite" precision mirror diagonal (1/10th wave P-V quoted). This diagonal has a durable and highly efficient reflective coating. The interior is fully anti reflection ribbed and coated. The male 2 inch barrel of this diagonal is threaded to accept 48mm photo and visual filters.
Left: TeleVue Everbrite 2" Mirror Diagonal and TeleVue 2" to 1.25" Reducer showing no mar clamp lock mechanisms (64,909 bytes).
The "Everbrite" mirror features a high technology dielectric coating developed originally for military optics used in hostile environments such as blowing desert sand. This TeleVue 2 inch diagonal has no aluminum or other reflective metal coating. Instead, the reflective element consists of about fifty layers of thin film oxides similar to those used in antireflection coatings. These coatings are deposited into the glass by an electron beam evaporator at a high temperature. The result is that reflectivity is above 99% over the entire 4000 to 7000 Angstrom photo-visual range. Thin film coatings have extremely low surface scatter compared to aluminum or enhanced aluminum coatings; examination with a laser source shows approximately a five fold improvement in surface scatter. This coating will provide optimum performance and a lifetime (or more) of use.
The mirror diagonal provides a comfortable viewing position for the observer by diverting the image at the rear of the telescope off axis by 90 degrees to the side, with minimal degradation of image quality. The view when using the telescope as it is provided will appear to be right side up, and is reversed left to right; this is not usually a problem for astronomy or nature observing because the image quality provided by the high quality mirror and 2 inch diameters panoramic oculars is exceptional. While Company Seven does offer optional 45 degree inclined image erecting prisms, these prisms can only accommodate 1.25 inch diameter oculars. Furthermore, the erecting prisms will not provide image quality to equal that of a good mirror diagonal; this is particularly perceptible at higher magnifications. However, for moderate to medium magnification applications where one needs correct images (such as to read numbers, etc.) then the optional prism should be suitable.
A TeleVue 2 inch to 1.25 inch reducer adapter is furnished to permit the use of 1.25 inch diameter accessories. The reducer is engineered with a collar to prevent long barreled eyepieces even with one filter attached from "bottoming out" against the mirror. This diagonal permits an observer to employ any of a broad selection of 2 or 1.25 inch diameter oculars. The lock screw with a knurled head that is at the proximal (to the operator) end of the female 2 inch barrel adjusts tension to retain accessories such as the 2 to 1.25 inch reducer or lenses.
Click on image to see enlarged view (156,239 bytes).
TELEVUE NP127 mm f5.2 TELESCOPE SPECIFICATIONS
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Above: NP127is of 2010 as provided by TeleVue including fitted Carrying Case*, Photo/Visual 2 and 2.4 inch fittings, Lens Cover. *Case shown above is an original model, since replaced by similar case but with two handles arranged side by side (37,328 bytes). Click on image to see enlarged view (117,314 bytes). | ||||||||||||||||||||||||||||||||||||||||
Additional Reading: we host numerous articles and users guides in our Library including:
TeleVue NP127is Operating Guide, 2010 Model, the illustrated eleven (11) page guide by TeleVue explaining the telescope and how to configure it for use with the numerous Imaging System accessories. This includes advice about what adapter(s) are required to employ the telescope with various formats of digital and film cameras and of popular astronomical CCD imaging cameras. Download is 3,357,870 bytes in Adobe .pdf format.
In addition to our own ATA cases, Company Seven will offer optional padded soft cases to our customers in order to facilitate transport of the telescope.
| Eyepiece | Magnification | Actual field of view | Exit pupil |
|---|---|---|---|
| 35mm Panoptic | 19x | 3.4 degrees | 6.7mm |
| 31mm Nagler Type 5 | 21x | 3.6 degrees | 6mm |
| 22mm Nagler Type 4 | 30x | 2.7 degrees | 4.2mm |
| 22mm Panoptic | 30x | 2.1 degrees | 4.2mm |
| 19mm Panoptic | 35x | 1.9 degrees | 3.7mm |
| 17mm Nagler Type 4 | 39x | 2.1 degrees | 3.3mm |
| 13mm Ethos | 51x | 1.9 degrees | 2.5mm |
| 12mm Nagler Type 4 | 55x | 1.5 degrees | 2.3mm |
| 9mm Nagler 6 | 73x | 1.1 degrees | 1.7mm |
| 7mm Nagler 6 | 94X | 0.84 degrees | 1.35mm |
| 6mm Radian | 110x | 0.55 degrees | 1.15mm |
| 5mm Radian | 132x | 0.6 degrees | 1mm |
| 3mm Radian | 220x | 0.3 degrees | 0.6mm |
| 2mm Nagler Zoom | 330x | 0.17 degrees | 0.4mm |
* The telescope is capable of operating at magnifications greater than listed in this briefing above.
Contact Company Seven for additional advice about outfitting the NP127 for high magnification observing.
Above: Company Seven ATA Case custom fitted for a TeleVue NP101 telescope and accessories (138,840 bytes).
Click on image to see enlarged view (240,578 bytes).
Features include:
Please contact Company Seven for additional information and pricing.
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