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UV/IR cut filter for use with Quark Chromosphere. "Where" does it go?

ZWO ASI174MM Equipment UV/IR Cut Filters Sun
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Jamie Macdougall avatar
Jamie Macdougall avatar
Hi all,

I've seen countless posts online about "which" UV/IR cut filter to use with the Quark Chromosphere, but I'm struggling to understand "where" it should go.

I have an Esprit 100, Quark Chromosphere and ASI174MM. I've used the Quark and 174 combo successfully with an old 80mm scope, but never tried with the Esprit 100 - I know I need a UV/IR cut filter first. Everywhere online seems to point toward using the cut filter in front of the diagonal - but I'm not using a diagonal.

Am I right in thinking I can just purchase a 1.25" mounted filter and screw it to the front of the Quark (the silver threaded adaptor)?


I'm thinking this Baader filter will do the job nicely. I can get hold of it quite easily and I like Baader:
https://www.baader-planetarium.com/en/baader-uvir-cut--l-filter-–-cmos-optimized.html

Thanks for your thoughts.
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Luka Poropat avatar
Luka Poropat avatar
Yeah the UVIR should always go just after the primary objective, if using a diagonal before a diagonal, but also keep in mind once above 80mm I would consider a front mount energy rejection filter, you can never be too safe with a "normal" scope + quark. If you are asking if it can be mounted there on the quark im pretty sure yeah..
Jamie Macdougall avatar
Jamie Macdougall avatar
Luka Poropat:
Yeah the UVIR should always go just after the primary objective, if using a diagonal before a diagonal, but also keep in mind once above 80mm I would consider a front mount energy rejection filter, you can never be too safe with a "normal" scope + quark. If you are asking if it can be mounted there on the quark im pretty sure yeah..

Thanks Luka. My research so far shows that although a front mounted ERF is a great way to go, it's not strictly necessary below 150mm. That's directly from Daystar within the written documentation that comes with the Quark, but other sources online confirm this too. It's also *very* expensive 
andrea tasselli avatar
andrea tasselli avatar
Yes, that is exactly where I have mounted it on mine, with a 100mm refractor.
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Jamie Macdougall avatar
Jamie Macdougall avatar
andrea tasselli:
Yes, that is exactly I have mounted it on mine, with a 100mm refractor.

Excellent, thank you!
Nick Grundy avatar
Nick Grundy avatar
I had a spot for a 2" UV/IR at the front of my diagonal (keeping the mirror cooler as well)
Eddie Bagwell avatar
Eddie Bagwell avatar
The UV/IR filter can go anywhere in front of the Quark and if using a diagonal, it should be used just before it. A front ERF is not need for your size telescope. You are correct about the threads on the front of the Quark, a 1.25" filter can be placed there.

CS, Eddie
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