Tele Vue 2.5x 1.25-inch Powermate
Tele Vue 2.5x 1.25-inch Powermate
The Tele Vue 2.5X PowerMate Image Amplifier in 1.25-inch size. A Pupil-Corrector, Extender/ Amplifier at its best!
"While Barlows are powerful tools, the negative element defining them also limits their ability. The simple negative element Barlow increases eyepiece eye-relief. With short focal length eyepieces the effect is negligible. However, on long focal length eyepieces the exit pupil position moves well beyond the designer's intended position, resulting in vignetting with many eyepieces. This is why "Shorty" Barlows in particular, with their strong negative element often vignette and degrade long focus eyepieces. My 4-element form picks up where the Barlow concept can go no further. PowerMate is a technically universal solution, using a positive field lens to redirect field rays. The result is an exit pupil that stays where the eyepiece designer intended. With freedom from aberrations, greater magnification potential, and compact size, I hope you'll agree PowerMate raises the standard for image amplification." - Al Nagler
The 2.5X PowerMate is a 4-element concept which continues the tradition of full-field sharpness with optimum aberration control. Are you looking for long eye-relief? The Tele Vue PowerMate (#TE-PMT-2513) retains the eye-relief of long focal length eyepieces, while at high power... a bonus for all eyeglass wearers! What makes it special? The Tele Vue PowerMate consists of a negative doublet plus a positive "pupil-correcting" doublet. This 4-element system provides the magnifying function of a barlow without its limitations by restoring the field rays back to their original direction... as if the PowerMate wasn't there. The result is a pure magnification increase! The 2.5X is flexible for visual and imaging with all types of telescopes and eyepieces. Essentially parfocal, the Tele Vue PowerMate delivers nearly constant magnification regardless of image distance behind top surface. Vignetting, edge field aberrations and pupil movement are minimized.
For astro-imagers, check the "Gallery" tab for a chart which indicates the magnification as a function of distance from the Televue Powermate top surface to the imaging surface (CCD or film). Some of the finest Solar System images on this world have been made with Tele Vue PowerMates! Used singly or stacked, they help any scope achieve the long focal-length required to image details on the planets or solar surface. The increased image scale allows for imaging without an intervening eyepiece -- like in prime focus photography.
|Accessory Type||Adapters & Extensions|
|Barlow Or Extender||Focal Extender|
|Warranty||5 Year Warranty|
Quality build. Does what I need it to. Just wanted a little more focal length for planetary viewing/imaging. Fast shipping from OPT.
I bought this primarily for planetary imaging. I have used a cheap ED 2" barlow ,and it had color focusing issues on a color camera. I also used a Meade multi-element barlow, and it was better. I got the Televue Powermate in hopes of "no" issues, and I wanted the 2.5X for a f/25 setup. That said, I also just jumped into mono imaging with filters, so I can't speak to its performance on the color camera. Since I used every clear moment learning to use the camera, I never actually looked through it with an eyepiece. What I can attest to, is that as the highly magnified image of the planet drifted around on the sensor there was no detectable distortion of the image due to the Powermate. The imaging was only limited by the seeing. I have some Televue eyepieces that have never disappointed and this Powermate is a nice addition to the collection of good clean optics.
This powermate is great, it increases the power, ONLY the power, same crisp image, same contrast (of course more power = less ligth. My 13mm Nagler turned into a 5mm Nagler, high power with grat eye relief. With this powermate you can realy push to the limit magnification of your telescope. It is like is not there, realy is invisible. Recomended.