Re: [APML]: 500-700 mm range

[Wil Milan <wmilan@airdigital.com>]

Another excellent option in a scope of 500 - 700mm focal length is the Tele
Vue Genesis apo refractor. Unlike the AP Traveler and most other apo
refractors, the Genesis inherently has a very flat image field, so it
provides pin-sharp images from corner to corner of a 35mm frame with no
additional adapters or optics required. The other apo refractors commonly
seen (AP Traveler, etc.) typically require an add-on field flattener, which
you have to buy separately.

I have a number of photos on my astrophoto site
(http://www.psn.net/~airdigital/astrophoto.html) taken with a Genesis. Mine
is the original f/5 Genesis; the newer Genesis SDF and the similar Tele Vue
101 have slightly longer focal lengths (540mm vs 500mm) and even better
color correction (which is pretty good even on the original).

Wil M.
--
"When I consider your heavens, the work of your fingers,
the moon and the stars which You have set in place,
what is Man that you are mindful of him,
or the son of Man that you care for him?"  -- Psalm 8


charles@jon.cjfny.org wrote:

>
> OK Wierd question. I'm high on the flu right now. I'm looking for the
> sharpest instrument with a budget of about $2500 Max that has a focal
> length of 500-700mm for astrophotography. Something exotic might be
> interesting, but I am not into fidgeting with film chips. Sharp is
> crucial. I'm tired of piggyback to 200mm and squinting to make out
> various deep sky objects. I also want a fast system, with no color
> problems or coma.
>
> Right now I'm considering an AP Traveller or a Peter Ceravolo scope. I
> would like to know more about the Takahashi Epsilon-series astrographs.
> Any other suggestions for this focal length? There must be other
> choices...
>
> Charles