Andover Ha Filter

VENDORS WELCOME! Please, only solar equipment.
Post Reply
Sungazer
Ohhhhhh My!
Ohhhhhh My!
Posts: 54
Joined: Wed Apr 02, 2014 1:59 pm
Location: N.Gloucestershire
Been thanked: 1 time

Andover Ha Filter

Post by Sungazer »

For Sale , Andover Corp Optical Filter. No 656FSO3-12.5. MM. AM 94410. Ser No 08. This was purchased for a project Solar scope. But was not ever used. This comes with a light transmission sheet showing exact cut off, for the actual filter. Photos of filter and transmission sheet ,upon request .. I am looking for £70 ovno, to include UK Post.
Attachments
Filter
Filter
EA50913E-6C57-419A-8DB0-383BEC74C89F.jpeg (1.76 MiB) Viewed 391 times
Transmission Filter
Transmission Filter
8EBF13B0-A4AE-426A-9AEE-E855A3D8D5F8.jpeg (19.3 KiB) Viewed 391 times


User avatar
marktownley
Librarian
Librarian
Posts: 32118
Joined: Tue Oct 18, 2011 5:27 pm
Location: Brierley Hills, UK
Has thanked: 5735 times
Been thanked: 2654 times
Contact:

Re: Andover Ha Filter

Post by marktownley »

Hmmm. This may work with a quark...


Image
http://brierleyhillsolar.blogspot.co.uk/
Solar images, a collection of all the most up to date live solar data on the web, imaging & processing tutorials - please take a look!
User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 3724
Joined: Sun Nov 18, 2012 3:13 pm
Has thanked: 95 times
Been thanked: 264 times

Re: Andover Ha Filter

Post by Valery »

marktownley wrote: Mon May 03, 2021 7:43 pm Hmmm. This may work with a quark...
No, Mark, unfortunately, it will not work. It has 3nm banwidth, while a native QUARK's bloker-ERF has only 1nm bandwidth.


Valery


"Solar H alpha activity is the most dynamic and compelling thing you can see in a telescope, so spend accordingly." (c) Bob Yoesle.

Largest full size 185 - 356mm Dielectric Energy Rejection Filters (D-ERF) by ARIES Instruments.
minhlead
Im an EXPERT!
Im an EXPERT!
Posts: 305
Joined: Sun Apr 25, 2021 9:36 pm
Location: Ha Noi, Vietnam
Has thanked: 342 times
Been thanked: 343 times
Contact:

Re: Andover Ha Filter

Post by minhlead »

Valery wrote: Tue Sep 14, 2021 5:26 am
marktownley wrote: Mon May 03, 2021 7:43 pm Hmmm. This may work with a quark...
No, Mark, unfortunately, it will not work. It has 3nm banwidth, while a native QUARK's bloker-ERF has only 1nm bandwidth.


Valery
Valery. I was just thinking. Since the bandpass of blocking filter so narrow, wouldn't they be killer DSO filter, no?
I am using a 3nm filter in a bortle 9 and sometimes I still feel I could use more light pollution cut off. I know the transmission will be low but I think I can make it work by extends exposure time.
I wonder if anyone used a blocking filter for this application?


Minh.
Loves from Viet Nam <3
My gear:
Scope: Sharpstar Al107PH @F/7 + Askar 400FRA @F/7
Mount: iOptron CEM25P
Camera: QHY294C (color camera shot at bin 2x2 mono mode)
Quark Chromosphere
george9
Ohhhhhh My!
Ohhhhhh My!
Posts: 185
Joined: Tue Jan 26, 2016 1:28 am
Has thanked: 17 times
Been thanked: 28 times

Re: Andover Ha Filter

Post by george9 »

I use some H-alpha filters for a night vision scope in very bright pollution (like inner city).

1" 1nm filter from Solar Spectrum with >90% transmission and steep sides (triple cavity) - shows pretty much everything you can take a picture of including Barnard's Loop, Gamma Cygni Nebula, Horsehead. Neat to see those things with your eyes from very bright skies, even if it is in a night-vision tube. Problem is the narrow field of view due to sensitivity to tilt at that bandwidth. We are talking about big tilt in a night-vision scope. (It's primary use is for solar prominences.)

2" 3nm Antlia - shows the same nighttime objects, not nearly as well but wider field of view

2" 7nm Baader - even wider field of view but you really start losing the dim nebulae

I am not sure if most typical solar blocking filters have high-enough transmission for this.

George


minhlead
Im an EXPERT!
Im an EXPERT!
Posts: 305
Joined: Sun Apr 25, 2021 9:36 pm
Location: Ha Noi, Vietnam
Has thanked: 342 times
Been thanked: 343 times
Contact:

Re: Andover Ha Filter

Post by minhlead »

george9 wrote: Tue Sep 21, 2021 6:35 pm I use some H-alpha filters for a night vision scope in very bright pollution (like inner city).

1" 1nm filter from Solar Spectrum with >90% transmission and steep sides (triple cavity) - shows pretty much everything you can take a picture of including Barnard's Loop, Gamma Cygni Nebula, Horsehead. Neat to see those things with your eyes from very bright skies, even if it is in a night-vision tube. Problem is the narrow field of view due to sensitivity to tilt at that bandwidth. We are talking about big tilt in a night-vision scope. (It's primary use is for solar prominences.)

2" 3nm Antlia - shows the same nighttime objects, not nearly as well but wider field of view

2" 7nm Baader - even wider field of view but you really start losing the dim nebulae

I am not sure if most typical solar blocking filters have high-enough transmission for this.

George
Thanks Geogre for the information. Do you have picture taken with the blocking filter?


Minh.
Loves from Viet Nam <3
My gear:
Scope: Sharpstar Al107PH @F/7 + Askar 400FRA @F/7
Mount: iOptron CEM25P
Camera: QHY294C (color camera shot at bin 2x2 mono mode)
Quark Chromosphere
george9
Ohhhhhh My!
Ohhhhhh My!
Posts: 185
Joined: Tue Jan 26, 2016 1:28 am
Has thanked: 17 times
Been thanked: 28 times

Re: Andover Ha Filter

Post by george9 »

Hi. I am almost totally visual so not real photos. I can track down an iPhone shot of Barnard's Loop. It shows only half at a time due to tilting. The tilting is only an issue when used at 1x, i.e., the filter faces the sky, then the night vision scope. Barnard's Loop is 10 degrees across, and that is a lot of tilt. When I use a telescope with the filter before an eyepiece, there is not enough tilt to cause a detectible problem.

George


Post Reply