Baader Semi Apo Filter 2' against violet fringes of refractors

BA2458399

Baader
in stock

Baader Semi Apo Filter 2" against violet fringes of refractors

94,00 EUR
incl. 19 % Tax
excl. 6,00 EUR Shipping costs

Description

Semi Apo Filter 2" - Contrast enhancement and reduction of the false colour of refractor telescopes - without significant yellowish tone

The Semi Apo Filter by Baader has been tested on our open day. The results have been very positive!

Mode of operation
By selective out-filtration of those parts of the spectrum where the false color of achromatic refractores is significant, this disturbing effect is minimized. Contrast and image definition are improved.

Differences to Fringe Killer, Contrast Booster, Minus Violet filter:

Those filters have a similar effect. They reduce false colour but additionally the combine this with a Skyglow filter. The image also gets a yellowish touch. In some cases, e.g. for planetary observation, this is wanted.

The Semi Apo filter causes significantly less yellow fogging. The image has a warmer touch with a light yellow-green tone. It also has more transmission compared with a standard minus violet filter. It can also be used for deep-sky and double star observation.

The Semi Apo filter is a good addition to the Fringe Killer and the Contrast Booster. It can replace a minus violet filter and gives less colour shift.

For which telescopes is this filter recommended?
DThe Semi Apo filter is for all refractors with obvious false colour. The effect is best at fast rich-field achromats but even at ED refractors an improvement is visisble at bright objects.