Product series:
The ProPlanet 742 filter allows only infrared light with wavelengths of more than 742nm to pass through. In this wavelength range, seeing effects are significantly lower than in the visible spectrum range. This means that you can capture much sharper images than you are used to from your device and location.
Another advantage is that the filter keeps the sky background dark as dawn approaches, thereby partially allowing day-time planetary and lunar photography.
Transmission curve
Alternative: with very poor seeing and for devices with an aperture of 10" (250mm) or greater, an Astronomik ProPlanet IR 807 can be useful.