TS-Optics 10" f/4 ONTC Carbon Tube Newtonian telescope - fully customizable

ONTC Newtonian Telescopes from Teleskop Service are a unique system on the market

You choose the components and the bias of your telescope and get a Newtonian without compromises for reaching your astronomical goals. Just tell us what you want to do with the telescope and we make it according to your needs.

The ONTC Newtonian with 254 mm aperture and 1000 mm focal length:
The strengths of this telescope are compactness and transportability. The telescope can be combined with medium sized mounts like the Skywatcher EQ6 or the Celestron CGEM. Astrophotographers will appreciate the Newtonian for the high speed of f/4. With suited correctors, the speed can be increased to f/2.8.

The advantages of the ONTC telescopes in short:

optimized configuration for astrophotographic or visual use by choosing different focusers, focus positions or secondary mirror

Exchange of the secondary without problems - anytime

Only selected optics are used. Also the functionality of the optical and mechanical components are tested before sending out the ONTC.

Each ONTC Newtonian telescope comes with a complete manufacturing protocol including star test.

The edge of the secondary is blackened against reflexes and false light.

The carbon tube is made in Germany. It is manufactured in a carbon/rigid foam sandwich construction for a perfect stability at an unbeatable weight ratio

Fantastic temperature compensating performance - barely any temperature based focus drift

The mirror cells are manufactured in Germany, too. The telescope can be collimated completely without tools.

One telescope, many focal distances - due to different correctors! The correctors need different focus positions above the focuser. The tube offers three positions of the main mirror cell.

TS "Black" anti-reflective paint for maximum contrast

Many of our UNC and all ONTC Newtonian telescopes use the TS-Optics "Black" anti-reflective paint. It darkens the inside of the tube just as well as velour foil. The illustration shows how dark the anti-reflective paint is. The diagram (at the images at the top of this page) shows the direct comparison between the commonly used chalkboard paint and the anti-reflective paint.

Choose a suitable focuser in the "options" list

The free choice of the focuser makes the ONTC Newtonians unique. Thus you can easily adapt your new telescope optimally to your wishes. Please do not forget to select the base for attaching the focuser to the tube. You can choose from our whole range. A few recommendations are given below:

UNCN2-G2 - TS 2" UNC Newtonian Crayford focuser - short

Economically priced 2" Crayford focuser for observing and photography with DSLR cameras. The short focuser needs only 75 mm optical path.

Item number of the necessary base: BAST-UNCN2G2 - please add to your order.




FTF2008BCR - Starlight Feather Touch 2" focuser - 20 mm draw tube travel

The best 2" focuser we know, for maximal stability without compromises. In addition, the focuser is very short, together with the base, it is only 50 mm heigh.

Item number of the necessary base: BA20CL-303mm - please add to your order.




Orion ACU-3S 3" Crayford focuser with M82x1 thread

The massive 3" focuser is our recommendation for astrophotographers who want to work with a 3" Newtonian corrector (N-AGK3, TS 3" Wynne or TeleVue VIP-3010.) These correctors are screwed to the M82 thread of the focuser.

Item number of the necessary base: NB300-ORACU3 - please add to your order.




Starlight FTF3215B-A TRUE 3" Feather Touch Focuser

THE high-end focuser for Newtonian telescopes and real 3" correctors from TeleVue, ASA or TS Optics. with very precise 3" compression ring clamping - as good as screwed adaptions.

Item number of the necessary base: BA32CL-300 - please add to your order.

We recommend three focus positions above the 2" tube of the focuser:

1. astrophotography with the standard coma correctors - 65 mm above the 2" tube (STANDARD Version)
This version is optimized for the standard correctors like the TS coma corrector, the GPU corrector, the Baader MPCC or the ASA Quattro. For visual use, you need to add the 2" extension tube - Art.Nr. TSV235.

2. astrophotographic use with the ASA 2" Reducer/corrector - 90 mm above the 2" tube
This position is ideal for the use of the ASA Reducer/corrector ASA2KORRR. The reducer brings the system up from f/4 to f/2.8.

3. Visual use - 35 mm above 2" tube
We recommend that version for visual use of the telescope. For this telescope line, we recommend the 58 mm secondary mirror. The 2" Paracorr VIP-2010 also works fine with this focus position.

The focus positions are calculated and achieved by changing the primary mirrors position. Of course you can also get other positions if you want. For expample if you want to use a 3" coma corrector. The three we mentioned are the most common ones.

Further customizable parts of the ONTC Newtonian telescopes:

If you order the instrument via our webshop, you can send us a notice in the text field below the payment methods. There is a textfield "Informations concerning your order" where you can tell us what you want to have. The alternative is dropping us an email : info@teleskop-service.de

Tube color - carbon nature or laminated - included in the price:

Instead of a neat carbon glossy film, we can also offer a hard constrast white finish. Other colours are also possible, but bright colours will show more signs of wear if transported frequently.

Rings or bar directly connected to the tube - no change of the price:

The scope of delivery also includes rings with a flat base on both sides. According to your wish, we can also attach a dovetail bar (Losmandy or Vixen style) directly to the tube. If choosing that modification, the tube gets additional fibre layers where necessary.

Assembly and collimation instructions

The telescope is delivered disassembled into several units for safety. The assembly and adjustment are not complicated, you can download the instructions in advance. The PDF can be found here.

Astrophotographic results obtained with this telescope on Astrobin

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

General product video

Teleskop-Service has made an information video about the UNC and ONTC telescopes:

Astrophotographic results obtained with this telescope on Astrobin

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

Astro Images made with the ONTC 1010

NGC 253 - Allan Greiner... the ONTC mirror is excellent and the carbon fiber tube held focus for over 2 hours without change.

Telescope: 10" f/4 ONTC Newtonian

Exposure time: 57x2 min (22x L and 35x RGB)

Camera: QHY9 Mono

Filter: Astronomik Filter

Correktor: Baader RCC1 Koma Correktor

Guiding: with TSOAG9 Off Axis Guider

IC 1805 Wolfgang Ransburg
The ONTC was equipped with the carbon double spider which leads to the interferences in the spikes.

Telescope: 10" f/4 ONTC Newtonian

Exposure time: 160 min (66 min Luminanz rest RGB)

Camera: Atik 460EXM Mono

Filter: Baader RGB und 35nm H-Alpha Filter

Correktor: ASA Reducer 0,73x Koma Korrektor

Guiding: with TSOAG9 Off Axis Guider

M16 - Eagle Nebula

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

M33 - Triangulum Galaxy

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

Melotte 15 - Heart of the Heart Nebula

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

Bubble Nebula around WR 134

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

NGC 4565 - Needle Galaxy

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

NGC 2237 - Rosette Nebula

Photographer: Anthony Husson

Telescope: 10" f/4 ONTC Newtonian

Field corrector: TS-Optics NEWTON Coma Corrector 0.95x Maxfield 3-Element (TSKomakorr)

Filters: LRGB and Antlia 3 nm filters for SHO, all in ZWO 7x36mm filter wheel

Imaging camera: ZWO ASI294MM Pro

Guiding: ZWO ASI290MM on PrimaLuceLab guiding scope PLLCG60

Mount: iOptron CEM120 on iOptron Tri-Pier

Supernova remnant LBN 576 or CTB 1, formerly Abell 85

Photographer: Reg Pratt

Telescope: 10" f/4 ONTC Newtonian (ONTC1010)

Field Corrector: TS-Optics NEWTONIAN Coma Corrector 1.0x Superflat 4-Element (TSGPU)

Filters: H-alpha, O-III, RGB

Imaging camera: ZWO ASI2600MM Pro (ASI2600MM-P)

Exposure: H-alpha 3 nm 17.35 h, O-III 3 nm 48.82 h, RGB 5 min each; total 66.17 h

Mount: iOptron CEM70 (C70A)

NGC 7000 - North America Nebula

Photographer: Chino Morro

Telescope: 10" f/4 ONTC Newtonian (ONTC1010)

Imaging camera: ZWO ASI2600MC Pro (ASI2600MC-P)

Guide optics: ZWO Large Off Axis Guider (ZWO-OAG-L)

Guiding camera: ZWO ASI178MM (ASI178MM)

Mount: iOptron GEM45 with iPolar and LiteRoc tripod (IO7603A)

Messier 17 - Omega Nebula

Photographer: Chino Morro

Telescope: 10" f/4 ONTC Newtonian (ONTC1010)

Imaging camera: ZWO ASI2600MC Pro (ASI2600MC-P)

Guide optics: ZWO Large Off Axis Guider (ZWO-OAG-L)

Guiding camera: ZWO ASI178MM (ASI178MM)

Mount: iOptron GEM45 with iPolar and LiteRoc tripod (IO7603A)

Messier 8 - Lagoon Nebula

Photographer: Chino Morro

Telescope: 10" f/4 ONTC Newtonian (ONTC1010)

Imaging camera: ZWO ASI2600MC Pro (ASI2600MC-P)

Guide optics: ZWO Large Off Axis Guider (ZWO-OAG-L)

Guiding camera: ZWO ASI178MM (ASI178MM)

Mount: iOptron GEM45 with iPolar and LiteRoc tripod (IO7603A)