astroram New Member
- Skill Level
- Time with Product
Sep 3, 2009
- User Notes:
Skywatcher PRO ED 120F7.5 Gold versionPros:
Exceptional well figured, color fee at focus APO optics.Cons:
The W.O. focuser had some trouble at zenith with heavy eyepiecesComments:
Well after a few months I am quite impressed with this scope. I owned a great Celestron Fluorite 102 F8.8 made by Vixen with exceptional optics to say the least. Then a funny thing happened to me. Some months back a telescope vendor started blowing out these little Celestron 80 ED scope for about $250. It stated it utilized FPL53 glass sourced from Japan. Always wanting a quality grab and go scope, but not having the big bucks, I took a gamble on this little 80mm APO. My first views through that scope just blew me away; it kept taking power, and comparing it to My C102F, the image pretty much held its own, not only in resolution, but in color fidelity as well. It caused me to think about these Chinese ED FPL53 scopes on the market. I now wanted more aperture, so I gambled. I sold my C102F and intended to buy an EON 120 at the time. But I saw an ad in an astronomy classified for a used Skywatcher PRO ED 120 OTA with an upgraded William Optics rotatable crayford focuser with fine focus, the case and the rings for about $500 less than the EON. I snapped it up, and have not regretted selling that outstanding Celestron C102F refractor. The images this 120ED scope produces are outstanding, and to be honest, I don't notice any difference in how objects look color wise compared to what I have been accustom to with the fluorite. The only difference I see is brighter images,and more resolution. The moonlight 2 speed focuser I had on the C102F was smoother than this WO focuser, but having the ability to rotate the focuser and finder is a HUGE advantage. If I had to do this all over again knowing what I know now, I would have done it in a second. These are optically fantastic, and very portable telescopes. We are quite fortunate having these exceptional scopes at such reasonable prices.
The Dimensions: The 120 PRO ED is 31 inches in length when racked in without dew shield, from objective end to focuser end . The cell diameter is 5 and 1/4 inches. The Williams Optics dual speed 10:1 reduction focuser is rotatable, and it also has micro baffling. Again the objective coatings are green and appear uniform. The 8x50 finders optics are very sharp. It attaches by a dovetail to the OTA. The dew shield is only 6 and 1/4 inches in length
The optics: With the star test I used my TeleVue 2" Everbrite and 7mm Type 1 Nagler. Now the star test. While using a 7mm Nagler the OUTSIDE of FOCUS image on Arcturus showed one bright outer ring and the remaining dimmer rings equal in intensity and concentricity. The second ring was very slightly brighter than the remaining inner rings. There was also just a slight hint of violet on the disk of the inner rings. INSIDE of FOCUS on Arcturus showed again one bright outer ring and the rest of equal intensity. I did see a hint of yellow in the inner rings and a slight hint of violet outside the outermost bright ring. Now turning to Vega with the focuser adjusted to the INSIDE of FOCUS, there was just outside the brightest first ring, some slight violet and the inner rings were equally illuminated; not pure white but with a yellow greenish tinge. OUTSIDE of FOCUS, the outer bright ring had greenish yellow tinge while the equally illuminated inner rings had the some slight degree of violet. AT FOCUS the diffraction disc was white with some slight red shimmering in and out of view. The first two diffraction rings had hints of violet shimmering but I attribute that to atmospheric turbulence. , this scope is doing what a good APO refractor does, and that is to focus light into as small a point as possible.
While Viewing the double double in Lyra with the 7mm Nagler I could not discern any false color. The ED 120 scope easily split Epsilon Lyre into four tight airy disks. Using my 3.5mm Nagler made the view just that much more pleasurable. Unfortunately on none of the days that I tested the scope, did the atmosphere settle down enough so that I could utilize stupidly high powers!! Now turning to Saturn low in the SW horizon I easily saw the shadow of the rings on the disk of the planet and showed the disk as a creamy white in appearance.
Moving the scopes over to Porrima the tough double in Virgo I wasn't sure what to expect. This star is a good test for a quality 4 to 6 inch scope, and the ED 120 scope did not let me down on this one. Through the 120ED, the barbell shape with the 7mm Nagler was evident, I can't commit to saying I saw total separation though, it most likely was due to atmosphere. Inserting the 3.5mm Nagler, separating the pair was a snap!!
PROS: Exceptional well figured optics. The star test was nearly text book perfect, and using Suiter as a guide I would have to rate the optics at better then 1/6 wave.
CONS: noneSort by