Teleskop Austria Logo
LACERTA GmbH | Wien | Linz
BBlogger   Facebook   YouTube   Newsletter   EN   HU   DE   JP
Teleskop Austria Logo
LACERTA GmbH | Wien | Linz

1.25" star diagonal with 99% reflection, dielectric coating, L/10 PtV
(Castell: zen99c1)

59.88 EUR
(Gross prices are calculated with 19% or 7% VAT. If your country-specific VAT is higher, we take over LACERTA GmbH the additional tax costs)
plus shipping

Brandname:  Castell
Connention: 31,7mm
Reflection: 99%
Degree: 90°
Shipping weight:  1kg (Shipping costs)
EAN Code: 

(The stock is for information only and includes items that have already been reserved)
Wien: pre-ordering availble
Linz: only 2  remaining
Warehouse: in Stock
Opening hours

Seen cheaper somewhere?

Perhaps the lowest price in Europe ...

... for a dielectric zenith mirror with 99% reflection?

99% reflection and long life

Thanks to dielectric (non-metallic) coating, the Castell zenith mirror not only has a high reflectance of 99%, but also a long service life. The long service life is achieved because the non-metallic dielectric surface reacts much less with the acids and bases in the air than an aluminum coating with a quartz protective layer.

Ring clamping instead of fixing screws

The 31.7mm socket has a ring clamp with a large knurled screw.

Test: checking the reflection

Test procedure: Take a test photos with a camera through the diagonal (ISO200, manual mode), then measure the brightness value in Photoshop using a histogram.
This test serves as an estimate of the zenith reflection. The following models were tested:

  • LACERTA (nominal value:99%)
    Measured: Luminance = 98.9% Green / Visual = 99.2%
    (Very high reflectivity in the entire RGB range, but also the most expensive zenith mirror in this test series. It is identical to other well-known models)
  • SkyWatcher (nominal value:99%)
    Measured: Luminance = 96.1% Green / Visual = 95.3%
    (evenly in the entire RGB range, but shows less reflectivity than advertised both in luminance and in green / visual)
  • Castell (nominal value:99%)
    (Visually, it reaches almost 99%; in the blue area, however, a little less reflectivity and therefore a slightly yellow tinge; but is advantageous for Fraunhofer refractors with blue halos)
    Measured: Luminance = 95.3% Green / Visual = 98.2%
  • SkyWatcher (nominal value:91%)
    Measured: Luminance = 90.3% Green / Visual = 92.4%
    (As advertised, a good zenith mirror without higher reflectivity criteria. The image is, however, much darker than in the other three zenith mirrors)

We recommend:
zenpri1 Takahashi Diagonal Prism MC 1,25", Made in Jap ... 113.00 EUR
zen99c2 2" star diagonal with 99% reflection, dielectric ... 99.90 EUR
bagOkular7 waist case eyepiece holder (Lacerta) 32.90 EUR
OutdoorOKs Outdoor Case Lacerta deLux (227x182x84mm - small) 29.90 EUR
AluCok Eyepiece case 28.90 EUR
AluOk Alu Case for eyepieces (deLux version) 59.90 EUR
CleanSetLa LACERTA Cleaning Set 4 in 1 (Cleaning Fluid, Microfiber ... 17.90 EUR





  • Impressum and Terms
    Company data
    Terms and conditions
    exclusion of liability
    revocation instruction

  • © 2005-2019 Lacerta GmbH.
    All rights reserved.