Dark Blue 435nm Bandpass Filter

TOOLS,

not ToysnmBlue 470nm Bandpass Filter

No reflections · No straylight · Maximum brightness

11⁄4”+ 2”-Premium Colored Glass-Filters

nm

fineoptically polished / 7-layer MC-coated

All substrates fineoptically polished. These filters
by far supersede the mediocre quality of common„flame polished“ color filters.
Fineoptical polish and 2 mm thickness allows
these filters to be inserted anywhere into theoptical path without introducing astigmatism orother defects. For instance they can be usedin front of a binocular viewer without degrading theimage in any way.
Substrates are free of striae and planeparallel
polished to within 30 seconds of arc. Thiseliminates any double images or ghosting due towedge errors in the glass.
The sets comprise three longpass and three
genuine bandpass filters, which act similar toa nebula filter, so that only a small portion of
the visual spectrum is transmitted to emphasize
certain planetary surface detail.
The sets consist of following colors(Note the spectral
trace for each color!)
11⁄4“2“ Dark blue (435 nm) # 2458302 # 2458312
 Bright blue (470 nm) # 2458303 # 2458313
 Green(500 nm) # 2458304 # 2458314
 Yellow(495 nm) # 2458301 # 2458315
 Orange(570 nm) # 2458306 # 2458316
 Red(610 nm) # 2458307 # 2458317
Transmission efficiencies for the three longpassfilters (Yellow, orange and red) peaks at 98 %,while the efficiency for the three bandpass-filters
peaks at almost 70 percent – unheard of for a
simple colored glass-filter!
 All filters have standard 11⁄4“ or 2“ eyepiece
filter threads, tested and optimized to fit allmost
all eyepieces on the market. Each filtercell has amale as well as a female thread to allow stacking
for narrower passbands or to combine with ourUV/IR-Cut-filter. The combination of the red RG 610
and IR-Cut-filter (11⁄4“ # 2459207 or 2“ # 2459210)
for instance results in an extremely narrow
H-α passband-filter – at an incredibly cheap price.

 The filter cell features the largest clear apertureof any 11⁄4“ or 2“ filter on the market – for complete
freedom from vignetting at any focal length.
 The front „crown“ incorporates milled notches,
which makes handling and threading the filter aneasy operation in the dark.
 All surfaces are treated with a 7-layer MultiCoating, featuring a mere 0.25 % residual reflection.
It is the most elaborate coating ever applied onto
amateur color filters, resulting in a filter free of any
false reflections under any incident angle of light.
 As mentioned on www.cloudynights.com:
LIGHT(-transmission) is the hottest commodity for
all planetary observation. Especially during highmagnification work „enough light“ is the deciding
factor for the recognition of subtlest planetary
surface detail, much more important than a hordeof different filters of mediocre execution.
Less is more:
7-layer MC-coatings not only provide a brighter
image – most important of all – they prevent thesoftening effect of scattered light!
Scattered light kills exactly those sublest features inplanetary detail that this filter business is all about.
Painstaking attention to coatings and perfect opticalfiguring are simple reasons why the image contrast
through these premium filters is so rock-hard.

Green 500nm Bandpass Filternm

Yellow 495nm Longpass Filternm

Orange 570 nm Longpass Filter

nm

Premium Color Filter-Set (6 pieces) 120,–
 196,–

11⁄4“ Item.-No.: 245 8300
2“ Item.-No.: 245 8310

Red 610nm Longpass Filter

For purchasing individual Filters see Item.-No.‘sat left. Prices for single filters are:11⁄4“  25,–

2“  36,–

For best cleaning results we recommend:

OPTICAL WONDER
Fineoptical Cleaning Fluid
100 ml · Item-No.: 2905007

Super-Microfibre Cloth
10 x 10 inch · Item-No.: 2905000

nmuidThe best cleaning flarswe have tested in 35seye
iceof rv !

www.baader-planetarium.de · kontakt @ baader-planetarium.de · www.celestron-nexstar.de