====== Filter ======

Nachfolgend sind detaillierte Informationen der zur Verfügung stehenden Filter aufgeführt.


====== Astrodon Photometrics Johnson-Cousins Filters ======

Für die Photometrie sind Johnson-Cousins Filter vorhanden (seit Dezember 2018). Es steht auch ein Klar-Filter zur Verfügung.

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 Die nachfolgenden Informationen sind der Seite https://farpointastro.com/ entnommen.
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{{ :astrodon-photometrics-uvbri.jpeg?400|}}

  * Spectral profiles designed after UV, B, V, Rc, Ic Johnson/Cousins
  * Improved B filter  extending blocking >1100 nm and eliminating small light leaks that affected measurements of reddest stars in our initial filters
  * 100% coated – no colored glass
  * Peak transmission guaranteed > 90%
  * <0.01%T(ave) typical out-of-band 300 – 1100 nm; additionally =<0.1% Tabs for B***
  * Striae-free, single fused silica substrates
  * 1/4-wave propagated wavefront prior to coating
  * <0.5 arcminute substrate parallelism
  * 3.000 +/-0.025 mm substrate thickness
  * Parfocal with all Astrodon filters
  * Edge-blackened
  * 1.25″ mounted
  * Substrate:                     3.0mm +/-0.025mm fused silica
  * Filter Size:                    25.4mm +/-0.1mm diameter
  * Clear Aperture:             Central 23.4mm diameter minimum
  * TWF:                           </= 1/4 lambda per any 25mm square area before coating
  * Parallelism:                   </=0.5 arcminute before coating
  * Coating:                        To edge of part
  * AOI:                            0 degree
  * Scratches:                     </= 0.06mm width; no limit on length
  * Particles/Bubbles:         </= 0.4mm dia.
  * Pinholes/Voids:             </= 0.2mm dia.
  * Edge Finish:                  As fabricated
  * Chips:                           </=0.5mm
  * Edge Treatment:           Edges blackened with Enthone M-0-N black epoxy ink.
  * Thickness </= 0.1mm. It may extend 0.5mm onto top and bottom surfaces. 
   


{{ :johson_overview.png?600 |}}

==== JOHNSON-COUSINS B∗∗∗ ====

{{ :johson_b.png?600 |}}


  * T = 50%: 377.0 nm +/- 5.7nm; T = 50%: 473.0 nm +/- 3.8 nm
  * 365 nm – 525 nm: match target curve by design – will not evaluate
  * 410 nm – 425 nm: Tmin >= 90%
  * 300 nm – 350 nm: Tave <=0.01%; 550 nm – 1100 nm: Tave <=0.01%; 560 nm – 1000 nm: Tabs <=0.1%
  * Back reflections with theoretical values < 0.4% average by design.Listenpunkt

==== JOHNSON-COUSINS V∗ ====
{{ :johson_v.png?600 |}}
  * T = 50%: 490.0 nm +/- 7.3nm; T = 50%: 589.2 nm +/- 4.7 nm
  * 478 nm – 640 nm: match target curve by design, will not evaluate
  * 518 nm – 532 nm: Tmin >= 95%
  * 300 nm – 460 nm: Tave <=0.01%; 670 nm – 1050 nm: Tave <=0.01%
  * Coating has been redesigned to minimize back reflections with theoretical values < 0.3% average.
====  JOHNSON-COUSINS Rc  ====

{{ :johson_rc.png?600 |}}
  * T = 50%: 567.3 nm +/- 8.5nm; T = 50%: 717.1 nm +/- 5.7 nm
  * 550 nm – 850 nm: match target curve by design – will not evaluate
  * 594 nm – 615 nm: Tmin >= 95%; 300 nm – 525 nm: Tave <=0.01%
  * 900 nm – 1050 nm: Tave <=0.01%; 860 nm – 900 nm: Tave <= 1.0%
==== JOHNSON-COUSINS Ic  ====

{{ :johson_ic.png?600 |}}
  * T = 50%: 721.8 nm +/- 10.8nm; T = 50%: 889.8 nm +/- 7.1 nm
  * 705 nm – 900 nm: match target curve by design – will not evaluate
  * 758 nm – 850 nm: Tmin >= 95%
  * 300 nm – 680 nm: Tave <=0.01%; 930 nm – 1050 nm: Tave <=0.01%


====== BAADER Filter ======
====== Astronomik Filter ======