Baader Solar Continuum Filter 7.5nm 2" (540nm)

Baader Solar Continuum 7.5nm 2" Filter (540nm)

Solar Continuum 2" 7.5nm Solar Continuum Filter, CWL 540nm with 2" thread.

A must for owners of achromatic refractors. This narrow band filter cuts the spectral range where the lens optics draw sharpest and most contrasty. The Continuous Solar Filter gives you back the power.
Improves contrast and reduces the effect of atmospheric turbulence (in combination with white light solar filters)
Huge contrast gain in monochrome photography even in pure color systems

• Important note: The Continuum Solar Filter should be used for purely VISUAL solar observation with an additional filter (e.g. Baader Herschel prism or AstroSolar security filter)

7.5 nm Solar Continuum filter - for visual and photographic observations of the Sun
The Solar Continuum filter is practically a narrow band filter of the photosphere for white light solar observation. It provides the highest contrast in the photosphere of the Sun. The filter functions as a monochromator: suppressing the effects of atmospheric turbulence and providing much sharper images.

Lens systems - including those for apochromatic, catadioptric or eyepiece - are traditionally optimized for the spectral range around 540 nm, as this is where our eye has the highest sensitivity. Therefore, this narrow-band filter blocks everything except for the spectral range where the optics of a lens performs with the greatest sharpness and contrast. The effect is greatest on achromatic lens telescopes; but it also has an effect on apochromatic telescopes, catadioptric systems and even pure mirror systems by reducing air turbulence.

As a monochromatic filter, it is ideal for use in monochromatic cameras and can even provide tremendous gain in pure color systems.

With a color camera, as with narrowband deep sky photography, it is less effective, as only the green pixels are used. Thus, while still benefiting from the higher image sharpness of the telescope optimized for green wavelengths (and reduced influences from air turbulence), with a color camera you cannot take full advantage of the better image quality compared to monochrome cameras, as you are effectively working with reduced camera resolution.

Compared to the previous model with a half-bandwidth of 10 nm, this filter has a half-bandwidth of only 7.5 nm, which further increases the contrast. It thus replaces both the previous 10nm Baader Solar Continuum filter and the 1 ¼" stacked filter #2458392. The single filter is so good that stacking is no longer necessary - the contrast gain of a single 7.5nm filter makes stacking unnecessary, and this performance is now also available in 2".

The 7.5nm Baader Solar Continuum filter will also be included in the scope of delivery of the Cool Ceramic Herschel Mark II prism, which is in preparation.

The 7.5 nm Baader Solar Continuum also offers all the advantages of the CMOS-optimized Baader filters:

• Higher contrast, matched to typical CMOS quantum efficiency and s/n ratio
• Reflex-Blocker™ coatings, for the highest absence of halos, even under the most adverse conditions regarding auxiliary optics
• Filter thickness identical to existing standards, with the utmost care for parfocality
• Blackened edges all around, with a filter side indicator in the form of a black outer edge at the front, to additionally eliminate any reflections due to light falling on the edge of a filter
• Each filter individually coated, with the coating edge sealed (NOT cut out of a larger plate with coatings left uncovered, read more)
• Life-Coat™: increasingly harder coatings to allow for a coating that will not age for life, even in the harshest environment

Technical specifications:

• NET WEIGHT (KG) 0.067
• TRANSMISSION RANGE 535 - 545 nm
• FILTER THICKNESS (WITHOUT FILTER CELL) 2 mm
• HBW (HALFBANDWIDTH) 7.5 nm
• CWL (CENTRAL WAVE LENGTH) 540 nm
• AR COATING Reflex-Blocker™ hard-coated, flat-optically polished AR COATING
• FILTER SIZE 2 inches
• CMOS FILTER USAGE, Contrast Enhancement, Solar
• FILTER ASSEMBLED Mounted (LPFC 6mm)
• FILTER TYPE Narrow band
• oNE OR SET? Single filter
• FILTER SHAPE round

COMMENTS TO NOTE:

- The single filter is so good that Stacked is no longer necessary: the contrast gain of a single 7.5 nm filter makes stacking unnecessary and this performance is now available in 2" for the first time.
- Huge contrast gain in monochrome photography, even in pure color systems.
- The Baader 7.5 nm Solar Continuum has all the advantages of the CMOS optimized Baader filters and is also included in the delivery of the new Cool Ceramic Herschel Prism Mark II, which is currently in preparation. The new Cool Ceramic Herschel Prism is also worth waiting for this reason. Please note that the previous models: the 1¼" (540 nm) Baader Solar Continuum Filter No. 2458390, the 1¼" stacked Baader Solar Continuum Filter No. 2458392 and the 2" Baader Solar Continuum Filter No. 2458391 - are no longer available.

Baader Solar Continuum Filter 7.5nm 2" (540nm)