BP is an abbreviation for bandpass: The filter opens at 642nm and closes again at 842nm . It blocks the longwave infrared, unlike Astronomik's two other ProPlanet filters.
Together with the Astronomik filters ProPlanet 742 and ProPlanet 807 , you can now select three wavelength ranges for infrared images to obtain optimal images.
With the ProPlanet 642 BP you get three filters in a single product: Depending on which camera you use the filter, it is a great tool for infrared photography with a digital camera, reduces seeing and amplified in high-resolution planetary and lunar photography contrasts. It is also a low-cost H-alpha filter for entry into the DeepSky astrophotography of emission nebulae.
- High contrast images with excellent color differentiation
- Great rendering of the Wood effect
- Avoid hot spots
- Exposure times as under "normal light"
- Great for IR movie shooting!
High-resolution lunar and planetary photography:
- Short exposure times
- Effective reduction of air turbulence (Seeing)
- Reinforced contrasts in the red area
- No ghosting and sharpness by blocking the long-wave IR
Deep-Sky Astrophotography of H-alpha Mists:
- Maximum transmission of the H-alpha line at 656nm
- Enormous contrast gain under light-polluted skies or moonlight
- Affordable entry into the H-alpha photography
- Easy focusing with LiveView possible!
Further field of application: Guiding in astrophotography . The 642BP in front of your autoguider improves the quality of your tracking significantly, as it minimizes the jumps through Seeing!