Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Use this section to discuss "standard" Baader/Coronado/ Lunt SolarView/ Daystar, etc… filters, cameras and scopes. No mods, just questions/ answers and reviews.
Post Reply
User avatar
astromemo
The Sun?
The Sun?
Posts: 1
Joined: Mon Jul 02, 2018 4:33 pm

Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Post by astromemo » Mon Jul 02, 2018 5:57 pm

Hi,

i have a new Daystar Quantum 0,5 and Explorer Scientific 127 APO.
My question: Do I need an ERF filter, or is it just a Baader UV / IR filter?

Thanks
Daystar Quantum 0,5a
Lunt LS80 B1800
Lunt LS152 B3400

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 2845
Joined: Sun Nov 18, 2012 3:13 pm

Re: Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Post by Valery » Tue Jul 03, 2018 3:41 pm

Better to use a full size DERF. Do not take these risks at your own duty.
"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.

User avatar
p_zetner
Almost There...
Almost There...
Posts: 794
Joined: Sun Mar 18, 2012 4:59 pm

Re: Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Post by p_zetner » Thu Jul 05, 2018 3:18 pm

Not to contradict Valery, but I’ve used the Baader uv/ir cut filter as ERF for the Daystar QPE0.6A on a 100mm f12 (Istar objective) with no problems. Daystar has recommended the use of full sized ERF for objective diameters larger than 100mm. A front mounted ERF is the best solution, especially as it reduces internal tube heating which can degrade seeing.

User avatar
Valery
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 2845
Joined: Sun Nov 18, 2012 3:13 pm

Re: Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Post by Valery » Fri Jul 06, 2018 3:51 pm

p_zetner wrote:
Thu Jul 05, 2018 3:18 pm
Not to contradict Valery, but I’ve used the Baader uv/ir cut filter as ERF for the Daystar QPE0.6A on a 100mm f12 (Istar objective) with no problems. Daystar has recommended the use of full sized ERF for objective diameters larger than 100mm. A front mounted ERF is the best solution, especially as it reduces internal tube heating which can degrade seeing.
Similar etalons manufacturer has suggested to use a full size ERF for such an expensive Ha- filters. Otherwise the longevity of a filter will shorten.


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.

User avatar
Astrograph
Im an EXPERT!
Im an EXPERT!
Posts: 200
Joined: Tue Aug 05, 2014 1:00 pm
Location: London
Contact:

Re: Can i use the Daystar Quantum 0,5 withe only Baader UV/IR?

Post by Astrograph » Fri Jul 06, 2018 4:10 pm

The Baader UV/IR on paper blocks more UV but in practice does not seem to be good for use as a basic internal ERF. Many years ago we suggested this filter and one day put a polariser behind it to tame the light level a little. The scope was a 100mm. The polariser did nothing. When checked its coating had burnt away! We also saw that Quarks 'went off band' after about 30min. You would think the blocking filter would kill any residual heat but maybe not. More tests showed that UV/IR cuts pass quite a lot of heat energy. Put you hand behind the filter. You will see what I mean. If you use a 35nm Ha filter the light is cool and this is much better for the Quantum.

Even so why buy an high end filter and then use a lower performance ERF. A dielectric ERF will not suffer from spherical aberration like an internal filter and overall will be sharper and higher contrast.

Post Reply

Who is online

Users browsing this forum: No registered users and 2 guests