T2 Camera Tilting Unit from Teleskop Service
TS Optics T2 tilting mechanism - for perfect field definition
It allows perfect alignment between camera and a slightly tilted focal plane
TS T2 Tilting Unit
Many astro photographers know the problem: one focuses as precisely as possible but in one or two corners, the stars are not pinpoints. Often, the result is a compromise by "tricking" the focus to a point where most of the image field has the best focus possible or cropping the image.
Some possible causes of this problem:
-- a tilted camera sensor (fragments of a millimetre are enough)
-- a tilted focuser
-- a tilted focal plane of the telescope (common at Newtonian telescopes)
-- tilted optical accessories by imprecise clamping
We have the solution:
With the TS optics tilting mechanism, the camera's sensor is aligned with the focal plane no matter what causes the tilt. You just have to keep the orientation of the complete accessory train.
And that's how it works:
The best way is a calibration by test images. Identify the "bad corner" in your photo and begin adjusting the TSJT2.
1. Loosen the counter screws (the small setting screws)
2. Slightly turn the adjustment screws close to the "bad corner"
3. Take a second image. If the situation has become worse, turn the adjustment screw in the other direction until the image is satisfying.
4. Finally, tighten the counter screws again.
... and be pleased by a significantly higher image quality!
- Connection threads: M42x0.75 - T2 (female at telescope / male at camera side)
- free inside diameter ... 38,5mm
- Back focus: 11mm (+/- 0,5mm - depends on adjustment situation)
- Adjustment by three adjustment and three counter screws
- Outside Diameter of the tilting mechanism ... 69mm
Experiences from Riccardo Cappelaro
The common German company Teleskop Service has recently announced a new interesting tilting mechanism, costing only 59€, useful for obtaining a perfect flat field.
It’s common, for some reasons (often who practice astrophotograpy with Newtonians, knows well this problem), like a tilted camera sensor, or a tilted focuser, or a misalignment caused from mechanical or optical accessories interposed between the CCD camera and the telescope, the image is affected from not pinpoint stars on one or more corners.
This adaptor lets, with 3 screws couples, to finely regulate the camera tilting and obtain a corrected image, from corner to corner (be careful if you have to use a corrector or reducer/corrector: especially with big sized CCD, like APS-C format, if the field is not flat natively, you’ll have to use a corrector, otherwise the tilting mechanism couldn’t adjust
something that is originally curved)
The adapter (product code TSJT2) has 3 screws couples, three counters (the bigger ones) and three adjustments (the smallest ones). The connections threads are T2 male/female (but is coming out a new version with T2 male and M48 female), the back focus in 11mm +/- 0.5mm depending on the adjustment situations, and the free inside diameter in
38,5mm. The mechanism diameter is 70 mm.
The mounting procedure is very easy, but is useful to take some tricks, especially if large bodies ccd camera are used, like Atik 383, rather than Starlight Xpress. My advice is to mount a T2 extensions, 10mm minum size, between the camera and the mechanism, to have a full access with the allen key. Expecially who uses Newtonians for astro photograpy,
in the case a DSLR is used, is better to use correctors with a long back focus like the Baader RCC or the GSO. If you use the “traditional” correctors as the Baader MPCC, with a back focus of 55mm, you couldn’t use the tilting mechanism. But if a CCD camera is used, with a typical back focus of 12-20mm, you can use a corrector like the MPCC and a T2
extensions (10mm min.) between the camera and the mechanism.
In the test I used a GSO f/4 Newtonian with a Baader MPCC, camera was an old QHY8 (APS-C sensor size). In my test I placed the 10mm T2 extension between the camera and the adapter: without doing this, I wouldn’t be able to have a full access to the collimation screws due to the big camera body. Taken a first image, the lower borders were with not
pinpoint stars. The regulation is very easy: unscrew the counter screw, move the adjustment screw (turned it for an half for the first time, to understand if I was in the right direction), take a second image and then check if you’re having a better or worse result and go in the right direction. If you tighten the adjustment screw the ring’s border will go up
and the other way around. In 10 minutes I got a good adjustment.
If you’ll remove the camera, be careful to mark all the positions (camera and accessories), so the next time you can
place your stuff with the right angle, in the right position and don’t have to re-collimate again.
I really advice this tilting mechanism, with a very low price, but with a high utility. Thanks to Teleskop Service for providing a sample for testing.