Question: Orion 80 mm ED

Is this a real APO? On orion's website it states: "finally an APO you can afford." Yet on some review websites they say it is "as close as an APO as you can get." My Question; Does an ED/flourite element make a refractor an APO? Or, does a real APO have a different lens configuration or something else different? Will images in the 80 ED meet that of a more distinguished APO of the same arperture and focal length? Thanks guys,
Marc

Marc,

I am not sure what official definition of "APO" is.
That said, I had one of these babies on an
optical bench setup last weekend, and the
performance is unbelievably good. Testing with
an artificial star at 500x showed a nice white Airy
disk with faint ring and fainter 2nd ring.
All I could find wrong with it was the slightest
trace of over-correction (maybe 1/10 wave) and
sightest trace of coma (collimation is probably
off by microscopic amount). No astigmatism
or anything else significant; optics are fairly close
to perfect. The patterns inside / outside focus
do show a little false color, but not much.
Color correction is very close to the TV85,
but not quite as good as AP Traveler and
somewhat farther from Vixen Fluorite.

You may remember Orion sold another 80/500 ED
"UltraScan" about ten years ago. This new one
is in another league altogether. Much, much
better color correction and lens figure.

Can't say they will all be this good, but I was
sure impressed. Considering the price, its just
unbelievable. Everything else about it was nice, too.
Nice dark green coatings. Nice baffling.
Smooth focusser. It is a little hefty compared to
TV85, but thats about only gripe I could find.

- John B.

Just something interesting I found:
Orion 80ED uses FPL-53 glass for the ED objective, which is the same glass used in Astro-Physics Scopes. Interesting.

Marc