It took a long time to improve the production of my optics to offer a broad range of different mirrors now. My main interest is on parabolic primary mirrors for Newtonian telescopes. I also work on flats, spherical, ellipsoid mirrors (e.g. for Dall-Kirkham-telescopes), or hyperbolic optics (e.g. for Ritchey-Chrétien-telescopes). Since the latter could only be realized in close coordination with the customer, please contact me to express your expectations and the purpose of the mirror.

Please find a table with my usual and standard sizes of common primary mirrors for Newtonian telescopes below. In addition to my standard sizes I can realize any other size from 12’’ to 32’’, any focal ratio from f/3.3 to f/∞, any substrate thickness from 21 to 41 mm. As focal lengths of more than 3200 mm require a larger effort, please ask explicitly for conditions.

Usually I use Schott Borofloat 33 or a substrate with equal physical properties. Borofloat 33 is established as best substrate for the sizes listed above. Any other kind of glass should be provided by the client.
If you would like to use glass ceramics instead of borosilicate glass because of its low thermal expansion coefficient, please bear in mind: Small and medium size mirrors are not limited by deformation of the surface under changing temperature, but by turbulence immediately in front of the mirror’s surface. This turbulence is fanned by the great thermal mass of the primary mirror and is maintained by the falling temperature during the night. Actually Zerodur has this turbulence in the same degree as any other glass of this dimension. What initially sounds advantageous – no thermal expansion of Zerodur – is done to naught in practice by the far more harmful releasing heat in form of turbulences because of the primary mirror as heat reservoir. As top priority, a mirror as thin as possible should be chosen. Only then you should think about employing a better substrate  quality than borosilicate glass provides.

Please note: Details of focal lengths and focal ratios are approximate figures! Usually my optics have a scattering in the focal length of up to + - 100mm. A mirror having a desired focal length of 2000mm actually receives a focal length between 1900mm and 2100mm. Of course a lower tolerance is possible, but this must necessarily be settled in advance. The average surcharge on the prices listed below for smaller focal length tolerances will be between 5% and 15%.

Which quality can you expect?

I deliver mirrors up to and including a diameter of 21 " which are superior to Strehl 0.9. Optics with a diameter from 21’’ to 32’’ are better than Strehl 0.8. In principle, these are minimum information that are significantly exceeded in most cases. In this context please note my paragraphs/comments/explanations on measurement methods  and examples.

If you have specific requirements, please do not hesitate to contact me.

You are looking for the greatest possible transparency when buying your telescope optics?

 

 

 

 

 

 

 

I enclose a CD to every mirror I deliver, containing the complete interferometric final evaluation. This CD contains every used interferogram of all measurement positions, and all software evaluations. You can also find a Quick Start Guide, which allows you to self-evaluate the interferograms.
A serial number is engraved on the back side of every mirror. This serial number
can be found as watermark on all enclosed interferometric single shots, so an unambiguous assignment of evaluation and the optics delivered is guaranteed.

             Standard price list for Newton-parabolic mirrors of Schott Borofloat or Suprax

Diameter

focal ratio

edge thickness

price (€)

355mm / approx. 14"

f/3.5

25mm

2700

355mm / approx. 14"

f/4

25mm

2450

355mm / approx. 14"

f/4.5

25mm

2350

355mm / approx. 14"

f/5

25mm

2200


400mm / approx. 16"


f/3.5


25mm


3375

400mm / approx. 16"

f/4

25mm

3150

400mm / approx. 16"

f/4.5

25mm

2875

400mm / approx. 16"

f/5

25mm

2700


460mm / approx. 18"


f/3.5


25mm


4900

460mm / approx. 18"

f/4

25mm

4350

460mm / approx. 18"

f/4.5

25mm

4100

460mm / approx. 18"

f/5

25mm

3950


535mm / approx. 21"


f/3.5


31mm


6200

535mm / approx. 21"

f/4

31mm

5500

535mm / approx. 21"

f/4.5

31mm

5000

535mm / approx. 21"

f/5

31mm

4800


600mm / approx. 23.5"

 
f/3.5


41mm


on demand

600mm / approx. 23.5"

f/4

41mm

7800

600mm / approx. 23.5"

f/4.5

41mm

7400


710mm / approx. 28"

 
on demand


on demand

 
on demand


810mm / approx. 32"

 
on demand


on demand


on demand


The prices are final prices for private customers including 19% VAT. They include further

  • 92% or better aluminum coating with protection layer
  • center mark for laser adjustment
  • backside Nauris logo
  • interferometric evaluation on CD
  • stable packaging
  • shipping (only valid for shipping in Germany. The carriage charges for overseas will be calculated and added upon receipt of order; charges depend on weight, size of parcel and delivery location).

Please ask for current delivery times. For precise information please add details regarding the desired diameter, focal ratio and material thickness to your request.
Please note: The ordering procedure of both the glass substrate and the mirror coating will vary by several weeks. My primary goal is to provide a mirror which you will enjoy for many years. The manufacture of precision optics is a complex process. Thus you cannot predict the exact labor input nor quantify precisely the time necessary. This is why any information about delivery time will be estimated to the best of my knowledge and is not binding. For general information about ordering, purchase, and delivery please check my Terms & Conditions.