I thought you preferred filters about half that band width. Though you
won't see them anywhere near that price. Anyway the pictures look good
to me. Maybe it is the steeper skirts you imply by the higher Q.

Rick


Richard Crisp wrote:
I recently got a chance to use my new 50.8mm Baader Planetarium 7nm
Ha filter. It works great and what a deal at about $325 based on
current exchange rates.

I shot two images with it on Thursday night last week in so so
seeing: one of The Crab (4 x 30 minutes) and one of M82 ( 5 x 30
minutes). All were shot with the home built 18" f/12.6 classical cass
on the Ca 2000 AP1200GTO using the CM10 camera with focal reducer
(F=3366mm approx).

Next tests will be on the AP180EDT refractor, but I have a few more
long focal length targets to use them with for now.

I really like the initial results. The images aren't so amazing in
terms of sharpness, hard to do that in 4+" seeing, but the filters
work really well, especially for the money.

As I understand it they have dual cavity construction which provides
a higher "Q" that single cavity/colored glass designs. But they are
priced very attractively, presumably because Baader makes them in-
house.

Anyway, I am jazzed to see such a nice product for such a low price.
As I understand it they will be producing 50MM square ones too for
the new big format sensors and I was told they would also be priced
aggressively, but I am not sure of the price.

Here are the images:


my favorite of the two, M82
http://www.narrowbandimaging.com/m82...er_ha_page.htm

Crab:
http://www.narrowbandimaging.com/m1_...er_ha_page.htm