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AP130 plus Herschel prism


Julien LECUYER
 

Hello everybody,

Is there a risk of using a Herschel Prism directly at the focus of an AP130EDF or should a special filter be added on the aperture?

Thanks in advance for your answers,

Julien.


Geert
 

Perfectly safe, I use this on a 150 apo. You need additional ND filter and/or Baader Solar Continuüm filter behind the prism though.

Geert

Op ma 15 feb. 2021 11:30 schreef Julien LECUYER <lecuyerj@...>:

Hello everybody,

Is there a risk of using a Herschel Prism directly at the focus of an AP130EDF or should a special filter be added on the aperture?

Thanks in advance for your answers,

Julien.


Eric Baumgartner
 

Hi, Julien:

 

I use a Herschel wedge with my 175 mm f/8.0 refractor without any issues. No need for a filter over the objective. Just ensure that you remove or securely cover any finder scope(s) that may be attached to the AP130, especially if you are doing outreach.

 

Eric Baumgartner

Redding, CT USA

 

From: <main@ap-ug.groups.io> on behalf of Julien LECUYER <lecuyerj@...>
Reply-To: <main@ap-ug.groups.io>
Date: Monday, February 15, 2021 at 5:30 AM
To: <main@ap-ug.groups.io>
Subject: [ap-ug] AP130 plus Herschel prism

 

Hello everybody,

Is there a risk of using a Herschel Prism directly at the focus of an AP130EDF or should a special filter be added on the aperture?

Thanks in advance for your answers,

Julien.


Roland Christen
 

No need for a filter for the 130EDF lens. Sunlight is not focused at the objective and passes thru without heating the glass.

Rolando



-----Original Message-----
From: Julien LECUYER <lecuyerj@...>
To: main@ap-ug.groups.io
Sent: Mon, Feb 15, 2021 4:30 am
Subject: [ap-ug] AP130 plus Herschel prism

Hello everybody,

Is there a risk of using a Herschel Prism directly at the focus of an AP130EDF or should a special filter be added on the aperture?

Thanks in advance for your answers,

Julien.


Julien LECUYER
 

Thanks to everyone for your feedbacks.

Is it possible to use a Daystar H-alpha quarks directly behind a diagonal without an ERF filter at the aperture?
Or do you think that behind an Herschel prism would be a better solution because the solar energy is limited?

Thanks,

Julien.


Geert
 

Julian, 

Herschel prism + Quark will not work, not enough light then. An ERF filter in front of that 130mm objective is the safest way, or a smaller ERF some distance before the Quark inside the OTA can work as well for short period of observation time.

Geert

Op di 16 feb. 2021 23:44 schreef Julien LECUYER <lecuyerj@...>:

Thanks to everyone for your feedbacks.

Is it possible to use a Daystar H-alpha quarks directly behind a diagonal without an ERF filter at the aperture?
Or do you think that behind an Herschel prism would be a better solution because the solar energy is limited?

Thanks,

Julien.


Julien LECUYER
 

Geert,

Thanks for your answer.
So, the best solution is an ERF filter in front of objective. I see a Baader one at 135 mm of diameter.


Julien.

Le 17 févr. 2021 à 08:17, Geert <geert.vandenbulcke@...> a écrit :

Julian, 

Herschel prism + Quark will not work, not enough light then. An ERF filter in front of that 130mm objective is the safest way, or a smaller ERF some distance before the Quark inside the OTA can work as well for short period of observation time.

Geert

Op di 16 feb. 2021 23:44 schreef Julien LECUYER <lecuyerj@...>:
Thanks to everyone for your feedbacks.

Is it possible to use a Daystar H-alpha quarks directly behind a diagonal without an ERF filter at the aperture?
Or do you think that behind an Herschel prism would be a better solution because the solar energy is limited?

Thanks,

Julien.