This is a description of a fast telephoto setup for narrowband astrophotography. It consists of an ICX814-based CCD camera, a Carl Zeiss Sonnar 135mm (f/2) APO lens, a guiding subsystem, an Astroholgi MicroFocuser (AH-MF), an Avalon Zero mount and a Gitzo GT5532s tripod. Seemly invisible customized parts are placed at key positions to make those standard products work together as one system. This portable configuration offers a wide 6x5° field-of-view (FOV) and a useful resolution of 5.6".
Critical Focus Zone (CFZ): 29,15μm
Camera: hosting a KAI-11000 sensor
FOV: 5° 21' 24'' x 3° 34' 16''
Sensitivity at Hα line: 30%
Typical read noise: 11 e-
Dynamics: 9.4 mag, 5455 grayscale values
Pixel array: 11 MPixels
Mount: 30kg class GoTo mount
Tripod: Wooden or metal tripod for 60kg load
The Future is now
Scope: 6.6cm aperture, 11 lenses, 135mm, f/2
Critical Focus Zone (CFZ): 8,8μm
Camera: ICX814-based CCD
FOV: 5° 17' 36'' x 4° 14' 5''
Sensitivity at Hα line: 65%
Typical read noise: 5 e-
Dynamics: 8.7 mag, 3600 grayscale values
Pixel array: 9 MPixels
Mount: Avalon Zero GoTo mount
Tripod: Gitzo GT5532s
May the Force be with you!
Taming a Wild Horse
Filter thread M77 x 0,75
Dimensions (with caps) ZE: 130 mm
Aperture range f/2 – f/22
- monochrome sensor that is best suited for narrowband work.
- short metal back distance (13mm).
- simple, comprehensible design.
- over 65% response at Hα line.
- regulated cooling system.
- low weight.
- high resolution resulted from its small 3.69μm pixels making it a good match for short focal lengths.
- acceptable 18000e- Full Well Capacity (FWC) and a low read noise of 5e- contributing to dynamic images.
- no CCD chamber with Argon, i.e. 2mm less glass in the optical path.
- supplied with stable, field-proven control software.
- massive constructed to securely grab the telephoto lens.
- rotatable by simply unscrew two Allen screws. You can rotate the AH-MF without seriously going out-of-focus even at the extreme f/2 f-stop.
- offer screw holes to mount an adapter plate for an optional guider scope.
- offer screw holes to mount a rotatable adapter plate to support the camera in order to avoid tilting.
- available in different colors.
Our guider is truly unconventional. It consists of:
- Tokina 300mm f/6.3 micro four third lens acting as a guider scope. Its metal back distance is 20mm.
- Baader heavy duty T2 quick release is mounted on the Tokina lens sticked with two-component adhesive.
- Quick-release adapter: Zeiss Micro Bajonet male to T2 male.
- Takahashi eyepiece adapter taken from our Takahashi FSQ telescope. It works like the Baader-Click-Lock for 1.25" to flexibly snap the Lodestar (allowing to focus the Lodestar). It provides a T2 to 1.25" adaption.
- Starlight Lodestar guiding camera, residing deep inside the ClickLock to come in focus.
The best light beams come through
- Baader 36mm filter set for Full-Frame-CCD, consisting of three filters - H-alpha 7nm , OIII 8,5nm , SII 8nm. The filters are round, 2mm thick, without cell.
- Baader RGB color filter set: 2mm thick, new 2015 version with steeper slope to better absorb the light pollution.
- The following filters which are also 2mm thick are used: Red filter , Green filter , Blue filter
- Possible filter variants could also be: Baader Highspeed Filter. Unfortunately, these are not available in 36mm size for the slim (10mm thick) filter drawer we have used.
This is why we have chosen it:
- low weight, high quality mount
- GoTo controller
- no worm backslash, because there are no worms.
- no counter weights required, due to its smart design.
- stable working software.
- mount controllable via PC or smartphone.
- no meridian tilt required during exposures.
- made in the European Union.
- Avalon Guiding adapter is on the other axis side of the telescope so that you can install a Guider there. A smart feature of the Avalon mount that saves passive counterweight.
- Two tiltable adjustment plates made by astroholgi.de (see photo) on the Guiding Adapter.
- Dove Tail Clamp Adaption on the adjustment plate (similar to Avalon GP clamp).
- Astroholgi Star Plate (see photo) to strengthen the tripod.
This setup addresses ambitious astrophotographers needing a high performance, portable system for narrowband work. Our ten thousand dollar baby embodies a sophisticated concept, high-grade mechanics, first-class optics and modern electronics. Its low power consumption and its adequate weight make it suitable for field use. Its resolution matches the common seeing conditions in most northern countries where useful nights are rare.