About Third Planet Optics (TPO) Imaging Newtonian Telescopes…
If you are looking for a telescope that does a great job of imaging but doesn't come with the cost of a Ritchey-Chretien, check out the TPO Imaging Newtonian line of telescopes! All of our Imaging Newtonian optical tube assemblies, offered in apertures from 6" - 12", have very fast optics for the widest fields possible. Image with a DSLR or small webcam all the way up to large sensor CCD cameras with these inexpensive yet effective Newtonians.
The optics on all TPO Imaging Newtonians consist of a parabolic primary mirror and an elliptical secondary, or diagonal. The mirrors are made from B270 white water optical crown glass, which is more thermally stable than glass traditionally used on other reflectors. A 91% aluminum coating is applied, and then over-coated with a layer of quartz for the ultimate in durability. The primary mirror cell is very sturdy, and has six collimation knobs that can be adjusted by hand with a push or pull of the knob. Collimation is made even easier due to the center spot marked on the primary mirror. The diagonal mirror is held in place with a thin four-vane spider.
There's a perfectly centered dot in the middle of the primary so you know exactly where your laser collimator should point. You stick the laser in where the eyepiece goes, so it bounces off of the secondary to the primary. If the primary is center marked, then all you have to do is match up your laser dot to the marked dot and you're collimated!
The optical tube assembly on the TPO Imaging Newtonian telescope is made of rolled steel and painted white. The ends of the tube are die-cast aluminum, which contribute to the OTA's rigidity. Steel is a bit heavier than traditional aluminum, but since it has a lower coefficient of thermal expansion, your telescope will tend to hold its shape (and therefore, hold focus) as temperatures fluctuate throughout the night. The inside of the OTA is painted in a matte black finish, which stops stray light in its tracks.
A 2" dual-speed Crayford-style focuser rounds out this package. The ridged focusing knobs are easy to turn, even with gloves on, and the 10:1 microfocusing dial allows for very small changes, or tweaks, in focus. It takes ten turns of the microfocusing knob to equal just one turn of the larger knob. There is also a little knob on the bottom of the focuser that controls the tension, so that you can make adjustments depending on the weight or distribution of your load. You will also receive a 1.25" compression ring adapter for use with 1.25" eyepieces, and a 35mm extension tube to help you match the back-focus requirements of your imaging equipment.
The telescope comes with dual split-hinged mounting rings that are made of die-cast aluminum and felted on the inside to cradle the OTA without scratching. There are threaded holes on the underside of the rings that allow installation on either a Vixen-style (included) or Losmandy-style dovetail plate. The top of the rings is also drilled so that you can mount accessories.
All TPO Imaging Newtonians come with an 8x50 straight-through finderscope. The ocular has a non-illuminated crosshair and has 13mm of eye relief. A quick-release mounting bracket is also included.
TPO 6" f/4 Imaging Newtonian Highlights…
Focal Ratio: f/4
Focal Length: 610mm
White rolled steel exterior, flat black interior for higher contrast
2" dual-speed 10:1 linear Crayford-style focuser with 35mm extension & 1.25" adapter
8X50 White Crosshair Finderscope with Bracket & Dovetail Shoe
Is this telescope like the a AstroTech version? Thanks!
Question by: Oscar on Jul 8, 2014 6:33:27 AM
Yes, both the TPO and Astro-Tech scopes are made by Guan Sheng Optical (GSO) and are nearly identical. The TPO scope includes a more robust focuser with a steel guide rail to minimize slipping with a bigger camera or eyepiece.
Answer by: Chris (Admin) on Jul 8, 2014 12:38:15 PM
Is the included focuser capable of holding a Canon EOS 7D?
Question by: Bilal on Jul 1, 2014 10:28:00 AM
The included focuser with this scope has been improved with the addition of a steel runner that stiffens the focuser tube and prevents it from tilting under heavier loads. As long as the tension screw under the focuser shaft is tightened adequately, the focuser will be able to carry a 7D and an appropriate coma corrector such as an MPCC. It won't be stable for a camera too much heavier, though, and for a camera in the 3-5 lb range like some CCD cameras with filter wheels, I would recommend considering an upgrade to a heavier focuser.
Answer by: Chris (Admin) on Jul 3, 2014 6:58:40 AM
Question by: Richard Lighthill on Nov 16, 2016 5:04:00 PM
The manufacturer does not make a focal reducer for this scope, though some customers have used the 2" ASA reducer A2-2KORRR, but that reducer runs over 3x what the telescope costs. At f/4, a coma corrector is likely more useful than a reducer.
Answer by: Chris Hendren on Nov 22, 2016 4:29:00 PM
TPO 6" f/4 Imaging Newtonian OTA... Can I use this as wide field visual scope on my 15lb capacity tripod mount ? Thanks, Karen...
Question by: Karen on Jun 16, 2014 9:07:26 AM
The total weight of this telescope is 13 pounds so if you're just using this for visual use. You should be just fine.
Since this is a fast optical system, a coma corrector will be necessary to get rid of the coma that this telescope will introduce. I would say that something like the MPCC from Baader would be a good choice.
Answer by: Roderick (Admin) on Jun 17, 2014 1:20:16 PM