- Summertime - Vacation Time
From August 5th to August 22nd we are on vacation and closed!
- Astronomik Lunar calendar for 2023
The Astronomik calendar of the Lunar phases in 2023 is ready.
- Chistmastime and New Year 2022-2023
We wish you a merry Chirstmastime and a happy and healthy 2023...
- Shipping methods
Shipping as registred good shipment is no longer available
- How to observe planetary nebulae
A very nice introduction to observing planetary nebulas written by Owen Brazell
- Astronomik Lunar calendar for 2022
The Astronomik calendar of the Lunar phases in 2022 is ready.
- Website down
Our website was down on dec 20st...
- H-alpha imaging with a unmodified EOS R
Imaging with an unmodified camera using a H-alpha filter
- Astronomik Lunar calendar for 2021
The Astronomik calendar of the Lunar phases in 2021 is ready.
- Back at work
After our closure during Xmas and new year we´re back at work
Transmission measurement of filters
You have just bought a new filter for your equipment and now you are wondering why it does not work as it should? Or perhaps you have stored some filters in your eyepiece case and you are unsure about their precision?
We have the answers to your questions!
This diagram shows the transmission curve of an Astronomik UHC filter (green) and a UHC filter from a manufacterer in China (red). You won't see very much through the filter represented by the red curve. So in this case, the "cheap" filter turns out to be a bad investment. Are you curious about how the transmission curves for your filters would look like? So why not give our new service a try?
Our spectrometer can measure in the spectral range of 380nm–1050nm with a resolution of 1.3 nm. It can measure the transmission of your filter either across the visual part of the spectrum, or across the full range of the spectrum (from 380nm to 1050nm), or at an arbitrary wavelength interval – depending on your choice. Emission line filters are checked for the precise position of the central wavelength (CWL) of transmission and full-width-half-maximum (FWHM) spread. Further details can be measured upon customer request. Our filter testing service includes a detailed graphical printout of your results so you can clearly see how your filter performs.
Our spectrometer is designed for high mobility. Hence, we decided to regularly take it with us during Astro fairs and telescope conventions. Come to our stand and get a measurement of your filters on the spot! Find out whether your filters can live up to your expectations! The charge for this service is EUR 25 (19% VAT included) or EUR 21 (VAT excluded for customers outside the EU).
Please read this nice article about cheap filters: (german only)
Günstige Filter für Deepsky- wirklich sinnvoll?
Shipping and handling is extra, usually a padded registered letter is sufficient (EUR 7,50 inside the EU / EUR 13 rest of the world). Discount: Have two filters measured and receive a 10% discount. Have five or more filters measured and get a 50% discount. If you have any questions, please drop us an email. We will be happy to assist you.)