- Astronomik Lunar calendar for 2024
The Astronomik calendar of the Lunar phases in 2024 is ready.
- Chistmastime and New Year 2023-2024
We wish you a merry Chirstmastime and a happy and healthy 2024...
- 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.
Methane band filter
The methane band filter is a dichroic filter with 50nm full width half maximum (FWHM) and a central wavelength of 880nm. You can use this filter to take images of the outer planets: The outer gaseous planets are very dark around 880nm as there is a strong absorption band of methane here. Due to this, the disks of the planets are very weak, nearly invisible. Using this filter, you may use much longer exposure times to capture faint moons, rings or ring fragments as they do reflect sunlight and have no absorption band.
The following image shows a comparison of methane band filters with 12nm FWHM, 50nm FWHM and an Astronomik red filter:
Image: Ralf Gerstheimer
This filter is not really suitable for beginners in planetary imaging. However, if you do own a larger instrument (> 10"/25cm) and a sensitive camera (e.g. a DMK from "The imaging Source" or comparable equipment) this filter will give you access to a large and interesting field of work!
Technical Data:
- Dichroic filter, mounted in 1,25" cell, free aperture 21,4mm
- Centrale Wavelength: 880nm (+/- 10nm)
- FWHM: 50nm
- Max. Transmission: 55%
- Blocking <0,1% (UV to 1,2µm)
- Thickness: 5,1mm
- Unmounted filters (D 1"/25,4mm) available upon request
- Typical transmission data as (ASCII) available upon request
- Individual transmission scan of your filter available upon request at a small additional fee
Methan Filter
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Methan Filter (880nm ZWL / FWHM 50nm)
excl. VAT (Non-EU): €192.44 incl. VAT (EU): €229.00