I purchased an ED50 (+ 27w MC eyepiece) a couple of months ago and it is certainly a good scope. However, after comparing it with my old Opticron HR66 (non-ED) + HDF eyepieces, I would not recommend the Nikon over the Opticron as someone’s ONLY scope. The Opticron (and I’d guess many other non-ED 60mm scopes – e.g. Nikon Fieldscope III and Kowa 601) is more pleasant to look through (perhaps because of the larger exit pupil resulting in easier eye placement and slightly brighter image) and the ability to bump the zoom up to 54x is INDISPENSIBLE at many of my birdwatching haunts (large freshwater wetlands and even larger estuaries). The Nikon does produce less chromatic aberration, slightly better colours and slightly better contrast, but in my book the Opticron wins - all things considered.
If I had no scope and had less than £500 to buy a new one, I’d go for a 60/66mm non-ED scope with zoom: the HR66 (£170 – MO return on w/hse express) + 28w HDF (£129) + 18-54x HDF (£159) = (£458); Kowa 602 (£239) + 20-60 eyepiece (£189); or Nikon Fieldscope III (£200 - MO return on w/hse express) + 20-60 eyepiece (£229). As to which of these three is best – I don’t know for sure, I’ve never tried them side-by-side. From what I’ve read, I’d guess that they could be ranked: Nikon; Kowa; Opticron.
That you could buy an ED50 now and, if you upgrade later, keep the ED50 as a travel scope is a good point – if you think you could cope without high magnification views for a while.
As other people have suggested, if you could go a bit above £500 or pick one up secondhand, then Opticron’s ES80ED and HR66ED (with HDF zoom) are two very good scopes - I’ve tried both and liked them very much. I’d say they beat anything I’ve mentioned above by some margin.
Regarding HR vs. GS, I tried a 65mm GS ED scope and found the image milky at higher magnifications with the HDF zoom – much worse than the non-ED HR66. The copy of the GS might have been a lemon though.
Iain
