Boren-Simon 10" f/2.8 PowerNewton Astrograph - Carbon Tube

With the Boren-Simon PowerNewtonian, you can take extremely deep astrophotographs within just one night.

Due to the professional TS2KORR reducer/corrector, you can enjoy the amazing performance with great sharpness and no reflection problems. You can gather enough raw material for the truly ultimate photograph of an object in one night!

The advantages of the 10" f/2.8 PowerNewtonian:

Short exposure times at f/2.8 - perfect also for cameras without cooling

Moderate exposure times when using narrowband filters

Very good field correction thanks to the TS2KORR corrector/reducer

High mechanical stability due to the carbon tube

Total length of only 950 mm, weight of 11.5 kg - can still be carried by portable mounts

Back focus 66.85 mm starting from the M48 thread of the TS2KORR reducer-corrector - also suitable for OAG

Illuminated and corrected field for APS-C format sensors

Only 35% obstruction - suited for visual use

The advantages of the 10" f/2.8 Astrograph against Celestrons Hyperstar system

The camera is mounted at the side of the tube, like with Newtonians. This way, the camera does neither cause obstruction nor does the heat loss of cooled CCD cameras impair the image quality.

The system is open to the front and therefore acclimatises faster as well as being more resistant to condensation.

The astrograph has a longer working distance than the Hyperstar and allows the usage of DSLR cameras or CCD cameras with filter wheels.

The TS UNCN2-G2 focuser:

A centerpiece of the TS PowerNewtons is the advanced TS UNCN2-G2 focuser. The focuser carries heavy cameras without tilting due to oversized ball bearings and a lateral guide. Only with this short focuser we could optimize the focus position. Despite the high luminosity, we get by with a secondary mirror of only 74 mm diameter in the small axis, which reduces contrast-reducing obstruction. Other features and benefits:

high stiffness with an extremely short overall length

generous back focus of 65 mm without reducer corrector - space enough for all common coma correctors and accessories like off-axis guider or filter wheel

precise 1:10 micro-reduction - for perfectly focused astrophotographs

Motor focus can be removed

equipped with additional thread M54x0.75

Illumination and correction of the 10" f/2.8 Astrograph:

The backfocus of the 10" f/2.8 PowerNewtonian is 67 mm. Sensors up to 22 mm diagonal are fully illuminated and corrected. Cameras up to APS-C format sensors (about 30 mm diagonal) can be used. The vignetting at the edge is then compensated by a flat.

Switch from fast f/2.8 to high-resolution f/4 in minutes with the TSGPU Coma Corrector:

One telescope, two focal lengths - this is also possible with the Boren-Simon astrograph. With the optional TSGPU Aplanatic Coma Corrector, optimized for f/4 systems, you can turn the fast f/2.8 astrograph into a high-resolution astrophotographically corrected Newtonian telescope with the focal ratio of 1:4 and 1000 mm focal length.

The conversion is done within a few minutes and the collimation is fully preserved.

The focus position at the Boren-Simon is optimized for the TS2KORRR reducer corrector with about 90 mm above the 2" receptacle of the focuser. The corrector needs this because of the focal length reducing effect. We recommend the BA2957031 spacer for the TSGPU. This spacer comes between the focuser and the connection plate on the tube. This moves the focuser 19 mm away from the tube.

The GPU is only partially pushed into the focuser. About 25 mm of the long 2" barrel are still visible. This kills 2 birds with one stone:

you automatically have a good position of the focuser for the corrector and do not need an extension.

the long housing of the corrector does not protrude into the tube. To get a clean stop, we recommend a 2" counter ring (item number 2zKonter).

The illumination of the Boren-Simon Astrograph:

The secondary mirror on the Boren Simon is optimized to fully illuminate a field lens of the corrector. Whether this is the GPU or the TS2KORRR reducer is not important. In both cases the illumination is limited by the corrector itself (diameter telescope side lens - distance to sensor). So any Boren-Simon will work well with the GPU. A flat is of course always necessary, both with the GPU and with TS2KORRR.

Astrophotographic results obtained with this telescope on Astrobin

Here you can find some astrophotographs made with this telescope model: Link to Astrobin

10" Astrograph with 250 mm aperture and carbon tube

TS UNCN2 focuser with 1:10 dual speed

4-element ED reducer and corrector

Tube rings

8x50 finderscope

No dovetail bar is supplied, please choose one. Two matching items are linked in the accessories section.

Astrophotographic results obtained with this telescope on Astrobin

Here you can find some astrophotographs made with this telescope model: Link to Astrobin

Answer from Teleskop-Service:
How do I get to 55 mm working distance??]
[!This is quite simple - always from the corrector to the camera:

distance 55 mm with T2 connection:

Tuning ring M48AbstimmA1
TSVF205
TSM48-T2L

Distance 55 mm with M48 connection:

Tuning ring M48AbstimmA1
TSVF210
Tuning ring M48AbstimmA1