Universal Paracorr Instructions
UNIVERSAL PARACORR INSTRUCTIONS
All Newtonian/Dobsonian telescopes can benefit from using a Tele Vue Paracorr (Parabola
Corrector) to eliminate coma in the image. Coma is the effect that makes off-center stars appear
like little comets (it becomes more apparent as stars move closer to the edge of the field). Any
Newtonian/Dobsonian telescope will benefit from the use of Paracorr, but those from f/3.5 to f/5.0
will see the greatest results. For example, the size of the diffraction-limited field expands by an incredible
36 times in area for an f/4.5 mirror! Paracorr essentially makes an f/4 scope perform like an f/8. Just
insert it into your 2" focuser like a 2" Barlow (it has a 15% [1.15x] magnification factor) and add Tele Vue Imaging System
components to suit your needs. It’s a recipe for perfection, when you use Tele Vue eyepieces.
This model Paracorr (PLU-1106) has the largest possible lens aperture to minimize any vignetting.
The key to obtaining proper coma correction is to space the lens surface 55mm
(±4mm) from the film plane or CCD chip.
Since the Universal Paracorr is designed
to use the spacers and adapters from
Tele Vue's Imaging System, any combination of spacer and camera attachment can be used in order to obtain the
proper lens to focal plane distance. For
example, using an SLR or DSLR with a T-ring
attached, you will simply need to add the
TRG-1072 Imaging System T-Ring adapter
to the Universal Paracorr.
When using CCD cameras, you
will need to know the distance of the
CCD chip to the surface of the camera.
Thread Tele Vue Imaging System
Subtract that figure from the required
Components onto the Universal
55mm to get the remaining necessary
Paracorr (PLU-1106) to match your
camera connections as well as obtain the necessary 55mm spacing
Lens surface rises above
between the Paracorr and the foCAUTION:
cal plane. Accessories shown are
It is important to keep
the T-ring Adapter (TRG-1072) and
in mind that the con0.250", 0.375", 0.500" and
vex lens surface (near1.000" spacers.
est to the camera) rises
above the Universal
Paracorr's metal work.
Always place the unit
down on the 2" diameter barrel to avoid
damage to the lens.
Vi s i o n a r y
32 Elkay Dr., Chester, New York 10918 (845) 469 - 4551 www.televue.com