© Baader Planetarium GmbH | 2023
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filter (1¼":
# 2458386
; 2":
# 2458386
),
which is also popular in planetary
photography and significantly reduces
seeing effects there as well. To use an
IR pass filter, the Solar Continuum Filter
must be removed. The filter can only be
used photographically.
TriBand and other telescopes
Even though we wrote in this manual
that the Herschel prism is only meant
for refractors, there are two exceptions:
The Baader TriBand Schmidt-Cassegrain telescopes and Schiefspiegler telescopes.
The Baader TriBand SCT are modified Schmidt-Cassegrain telescopes with 8", 9¼"
and 11" apertures that have an energy protection filter integrated into the Schmidt
corrector plate. Originally designed for high-resolution H-alpha observation with So-
larSpectrum or Baader SunDancer filters,
the special coating also allows deep-sky
narrowband photography and solar ob-
servation with a Herschel prism. Since the
TriBand coating is not transparent at 540
nm, the SolarContinuum must be remo-
ved and replaced with an ND or polarising
filter if necessary.
Schiefspiegler telescopes are somewhat
out of fashion and are not currently in series production. However, they are the only
reflecting telescopes that are obstruction-free and can provide sufficient backfocus for
a Herschel prism. Please refer to the operating instructions of your telescope to find
out whether your model is suitable for solar projection or a Herschel prism, or whether,
for example, correction lenses close to the focus prevent this use.
