Baader Dark Blue Color Filter

Baader Dark Blue Color Filter

Baader Dark Blue Color Filter is used for visual and photographic planetary observations. It aids in better detection of Venus phase. With this filter, the Violet Clearing on Mars can be seen better. It also enhances the Great Red Spot on Jupiter, the contrast between the belts and enhances the contrast between zones on Saturn.

Color filters for increased contrast of lunar and planetary observations

The Baader color filters are carefully prepared for amateur astronomical interests. The glass are coplaner fine optically polished. These filters exceed the quality of the usual "raw polished" (hot flamed) colored glass filters. Because they are fine optically polished, these filters can be at any point in the mean path - far ahead of the focal point (for example, in front of a binocular approach!) without causing defects (astigmastism) or to degrade the image otherwise in any way! The parallelisn of the optical surfaces is excellent with 30 arcseconds. Double images are absolutely excluded. For each filter colour, the transmission curve is supplied as a measurement protocol. Color filters are often identified with a Kodak Wratten number (W-point). Baader color filters were collected by astronomical experience and correspond to the respective wavelength range following filter by Wratten nomenclature: Baader-red filter ≅ W25, Baader-Orange filter ≅ W21, Baader-yellow filter≅ W12, Baader-green filter≅ W58, Baader-light blue filter ≅ W80A, Baader-dark blue filter≅ W38A These filters are screwed into the filter thread of eyepieces or planetary imaging cams (Skyris). A thread at either end of the filter allows the filters to be combined with each other or with other filters (for example with a Baader UV / IR infrared cut filter).  Transmission curves of 6 Baader color filters (dark blue, light blue, green, yellow, orange and red)

Features

• Largest free opening of all colour filters on the market to elimante any vignetting.
• CNC machined "grip crown" provides excellent handling and comfort.
• Both sides 7-layer AR coating with only 0.25% residual reflection per surface. This is the most antireflective that has ever been undertaken with color filters.
• The most important criterion for any kind of light filtering is brigthness. Certain spectral ranges at high magnification will only work at the highest light transmittance.
• The long-pass filter in this filter set offers 98% transmission and produces no flare. Unmatched by other brands. This can be seen in comparison with standard colour filters at once - the filter colour radiant downright.
• The combination of our infraread (IR) cut filter 1¼" and the RG 610 red filter results as an extremely narrow-band H-α pass filter for the CCD photography of red emission nebulae - at a ridcidulously low price!
• A wide range of adaptors allow the uses of T-2 photo threads (See: Baader Astro T-2 System™).

Baader Phantom Group Coating™

Developed by Baader Planetarium the coating is a 7-layer broadband coating with extremely low residual reflection. The term "Group" indicates that the respective most effective anti-reflection layer system was calculated for each type of glass of the filter. This means that the anti-reflection layers of different colour filters are different. They are calculated to provide the mximum for the respective filtered colour transmission values. Both sides of the filter are coated with 7-layer AR coating with only 0.25% residual reflection per surface. This is the most that has ever been provided for colour filters. The filter discs are screwed into the blackened aluminium frames and are delivered within a filter. Each filter is designed for multiple applications.

 

Dark Blue

MANUFACTURER	Baader Planetarium
SKU (#)	1.25"=2458302 | 2"=2458312
EAN CODE	4047825025111 | 4047825009708
WEIGHT (KG)	0.059 | 0.066
COLOUR	Dark Blue
TRANSMISSION RANGE	> 435 nm
FILTER THICKNESS (WITHOUT CELL)	2 mm
AR-COATING	Phantom Coating® Group, planeoptically polished
FILTER SIZE	1 25 inch | 2 inch
FILTER USAGE	Color, Planetary
FILTER MOUNTED	Mounted (LPFC 6mm)
TYPE OF FILTER	Bandpass
SINGLE OR SET?	Single Filter
FILTER SHAPE	round

 

In the Box