Quote:
Originally posted by atalas
No bum steer here Jonh, the 5.2mm ED are crap! and I didn't think the Andrews LE were that bad for half the money of the ED's .
The ED at 139.00 and LE's at 69.00 probably cheaper than that now.
How do the cheaper Andrews plossles compare to those John B at half the money again ?
Louie 
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Louie,
Here's something to start an agument
JB's eyepiece rating scale. The scale is solely my opinion only and takes into account things like eye-relief, AFOV, light transmission, sharpness, contrast, colour reproduction, EOF performance and the ability to perform well in fast scopes, but on an overall eyepiece "package" basis. Any assesment of an eyepiece is subjective and based solely on the observing preference of the individual. For instance, I now place a lot more importance on eye relief than what I used to do, probably because in the past eyepieces with long eye relief in all focal lengths didn't exist. This helps a lot with viewing comfort when observing for long periods, it also makes it a lot easier for people to observe with their glasses on. I place a lot more importance on an eyepiece's ability to provide sharp contrasty images with true colour reproduction and also good EOF performance than I do on a "superwide" FOV. I prefer an AFOV between 60 deg and 70 deg regardless of whether or not the scope is driven. Some people will place a lot more importance on a wide FOV than what I do and they will also be happy to tolerate softer images at the edge of that wide FOV than what I will.
The scale takes no account of price or value for money, in other words the best eyepiece gets the highest rating without regard to its price and the worst eyepiece gets the lowest rating without regard to the fact that it may actually be "good value" if it only costs $20. You also need to remember that some eyepiece series perform better in specific focal lengths than others. eg. I rate the 5,7 and 10mm Pentax XW's at 9.5/10 but only rate the 14mm and 20mm at 9/10 due to minor field curvature at EOF. Likewise the Nagler 22mm Nagler T4 is a little softer at the EOF than the 12mm and 17mm IMO. Also the 2" GSO Superviews perform slighly better in fast scopes than their 15mm and 20mm 1.25" cousins. I have given a rating to represent the standard achieved by the majority of focal lengths in an eyepiece series. You will also note that I have not made mention of many erfle design derivatives as they really don't perform well in scopes faster than F7 so they don't suit me.
You also need to remember there are a lot of eyepieces out there that I haven't used.
Here goes , shoot me down if you will guys and gals
TV Nagler T5 and T6 = 9.5/10 (tie for the best)
Pentax XW = 9.5/10 (tie for the best, narrower FOV offset by increased eye-relief and marginally sharper on axis IMO)
TV Radian = 9/10
TV Panoptic = 9/10
Pentax XL =9/10
TV Nagler T4 = 9/10 (slightly softer at EOF than T5 and T6 but longer ER)
Vixen Lanthanum Superwides = 8.5/10 excellent eyepiece just behind the best)
Zeiss orthoscopics = 8.5/10 (truly outstanding eyepiece with a narrow FOV and short ER)
TV Nagler T2 = 8.5/10 (were the standard for a long time)
Pentax SMC orthos 8/10 (only a tad behind the Zeiss orthos)
Original TV Nagler 8/10
Meade UWA 8/10
Tak LE = 7.5/10
Celestron Ultima/Orion Ultrascopic/Antares Elite = 7.5/10 (excellent image quality narrow FOV and short ER)
UO HD orthos = 7.5/10 (excellent image quality narrow FOV and short ER)
Brandon eyepieces (I think they are orthos) = 7.5/10
Made in Japan Meade 4000 series 5 element Plossls = 7/10 (these are vastly superior to the Made in PRC series 4000 Plossls)
Standard UO orthos (volcano tops) = 7/10
Standard Vixen Lanthanums = 7/10
Televue Widefields = 6.5/10
Meade SWA = 6.5/10
Widescan III = 6/10
UO Konigs and MK 70 series = 6/10
2" GSO Superview = 5.5/10
Synta Super plossls sold as Orion Sirius Plossl = 5/10
Widescan II = 5/10
Synta (Andrews) LE series = 4.5/10
2" BW Optik = 4/10
1.25" GSO Superviews = 4/10
GSO Plossls = 4/10
Eyepieces supplied standard with most scopes nowdays 3/10 and thats being generous in a lot of cases
CS- John B