Lacerta 200/800 Photo-Newton Reflector Telescope with Octo60 Focuser w/ Carbon Tube (Made in Germany, Assembled in Austria) with 4-lens GPU Comacorrector
These high quality custom made telescopes are the result of a co-operation between German, Austrian and Hungarian astrophotographers and specialist companies that resulted in significant improvements in the design and optical quality of the original telescope, but without breaking the bank. Whilst the carbon tubes are manufactured in Germany, the telescope is being assembled in Austria.
It became a very popular product recently due to the combination of affordable price and high quality, therefore there usually is a bit of a waiting list for these, manufacturing takes about 3-4 weeks, plus add a week to get it delivered to the UK, so realistically the usual lead time is 1 month.
A number of important optimizations have been carried out, which are described below:
Carbon Tube - Made in Germany
There are carbon tubes and there are Lacerta Carbon Tubes; don't make a mistake, these are not the same. For start, "Made in Germany" speaks for itself, Mr Klaushelmi knows exactly how to make carbon tubes. These carbon tubes are built stronger at both ends than in the middle in order to be able to optimally attach the main and retaining mirror brackets and at the same time to use the original pipe clamps, hence the increased stability...
Black Velor - instead of baffles
Baffles can suppress disturbing reflections, but they also have their faults and disadvantages. In a Newtonian system, the baffles should be placed at shorter distances near to the main mirror and further away at the other end of the tube. Also, the free aperture should not be exactly the same size as the main mirror! Otherwise a vignetting is preprogrammed before the light reaches the Newton's main mirror. However, unfortunately the frequently wrong "computer-optimized" baffle apertures not only miss their original function (to effectively suppress the reflections), but also bring vignetting into the field of view. But what is even worse, that the warmer air rising from the cooling main mirror has to climb over every single baffle, and this way it enters the path of the light beam several times.
Note: At night, the main mirror is always a few degrees warmer than the ambient temperature. And if the baffles have exactly the same free aperture as the main mirror, this flow distorts the wavefront before the light reaches the main mirror at all.
If, however, instead of the diaphragms we install black velor, there is no more vignetting and also no wavefront distortion anymore. And the inner reflections are guaranteed to be suppressed better than would be possible with an incorrectly calculated baffle/diaphragm system, which is completely eliminated by the tube wall opposite the eyepiece pullout. This is the point which directs most of the scattered light past the mirror into the eyepiece.
The eyepiece extension's tilt, noted in the SkyWatcher Quattro-Test made by the "Sterne und Weltraum Magazine" was corrected by a complete replacement of the focuser. A LACERTA Octo60mic focuser is installed, an extract with maximum stability which is achieved by the improvements we have developed. The Coma corrector is securely held on axis by a guide located in the OAZ tube, and is nevertheless fully rotatable. A center lock clamp keeps it safe, even with an eccentric filter wheel.
The Octo60 has a very precise guide and no play. Had been tested with 4 kg load. When we say "stable", this does not mean "a bit more stable than other focusers", it is REALLY VERY stable.
OPTIONAL: For extra charge a motorfocus can be installed, with stepper motor and temperature sensor.
(Rochus Hess): "The eyepiece extraction is indeed very stable and the corrector fits hair accuracy into the eyepiece pullout, you have not promised too much"
Secondary mirror blackened on the side:
It is often forgotten that unwanted reflections can also come from the side bright surface of the catching mirror. This can either be provided with a plastic holder, as with GSO tubes (however there is a risk of a nip at minus temperatures, as the coefficient of expansion of plastic is much larger than glass) or, as here, by simply blackaning of the secondary mirror's edge. This both favorable and effective at the same time.
OPTIONAL: for extra charge dew heater can be installed on the secondary mirror.
Quality constantly tested:
The mechanical framework conditions should be used to ensure that the optical quality can show its maximum. The conversion and optimization requires approx. 8-10 pure working hours. If you invest so much time in a rebuild, the main and secondary mirrors are also checked for their optical quality. Optics with low quality are screened out mercilessly by us.
This package also includes a 4-element coma corrector (optical design by Pal Gyulai / GPU / Hungary), which does not cause spherical aberration in the optical axis. To see the difference between the 4-lens GPU and the probably best two-eyed coma corrector (MPCC from Baader), you should open both the following images in two separate windows and then compare them. Observe the fine planetary nebula to the image center and the border size (courtesy of Burkhard K. from Bondorf)
Below: M51 - The Whirlpool Galaxy by Tommy Nawratil; for full resolution, full details and technical card, click on the image!
Telescope used: Lacerta Photo Newton
Camera used: ZWO ASI1600MM-COOLED
Guiding camera used: Lacerta MGEN
|Weight in Kg||10|