Jump to content


Recommendation for quark chromo pre-filter?

Recommended Posts


I'm using a quark chrome H-alpha filter on a skywatcher ST80 and I want to put a pre-filter in front to dump some of the heat. To this end I put a Baader 2" IR cut filter in the train and more or less lost the surface detail. 

Can anyone recommend a filter for this job and maybe explain why the filter had the effect it did ?

Also, my quark seems to be on-band with the knob turned to 1 o' clock when previously it was at about 6. All I did was store it indoors over the winter. Has this happened to anybody else ? Ambient is about 15 to 20 degrees in the info.

Finally, do people get better views with longer FR scopes ? This one is about f/5 and the contrast is lower than I am expecting.



Link to post
Share on other sites

Also - with a filter in the way - I also use the Baader UV/IR - you'll probably need to retune your Quark. An alternative suggested by Rupert at Astrogrpah is to use the Baader 35nm H-Alpha filter - I've just got one of those, so I'll keep you posted on any improvement or otherwise over the UV/IR - that is of course, when I get some sunshine.



Link to post
Share on other sites

I would prefer the Baader 35nm Ha filter, it is highly reflective which significantly reduces the heat loading on the rest of the system, if possible it should be tilted slightly to eliminate ghosting. I think there is a possibility that IR/UV filters still leak enough IR to take the edge off an image,also the residual spherical aberration of the F5 achromats has a similar effect. F6-F7 should be better.  :icon_biggrin:

  • Like 2
Link to post
Share on other sites

Thanks all. I have been searching for the passband info of the filter on the baader website and can't find it. I suspect the tail off might start at 6500 or so. 

I do need to try a longer focus refractory but all I have here are Petzvals. Might assemble one once I have the time.

I shall look into the narrower passband filter too.

What do you mean by retune other than to turn the knob? Adding the filter in the way shouldn't provide any interference effect causing the passband to move that I can think off. Do you know one ?




Link to post
Share on other sites

I've used the Baader 35nm Ha CCD filter as a replacement for the ITF in many solar scopes. The coating and bandwidth is the same as the Baader D-ERF.

No issues, no drama.


  • Like 1
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

  • Similar Content

    • By Lowjiber
      I'm still battling fairly heavy smoke from the wildfires west of my Las Vegas location.  Otherwise, seeing was 4/5.
      Thanks for the peek.
      Clear Skies

    • By Lowjiber
      I stumbled across this little ditty while waiting for the Quark to warm up
      Thanks for the peek.😀
      Clear Skies

    • By Minhlead
      I am looking for a Daystar Quark Chromosphere. I am looking for a perfectly working unit without any degradation in optics. A few recently took images from the eyepiece are welcomed. The price is as low as possible (of course). Cosmetic is not a concern. Give me a message here or email me at <private contact details removed> (remove the {xxx}) to see the email address. I'll pay via paypal and accept shipping worldwide. Thanks for your attention.
      Clear skies.
    • By TakMan
      Sorry for the delay in posting, was just too knackered yesterday to do processing justice...
      Was out making the most of another clear night and grabbing colour data for M106. By 2am the sky was really clearing up, but Julie had decided that our "one walk a day" should be to hear the dawn chorus - so after less than three hours sleep, we were heading back outside just after 5am to be treated to a beautiful sight of moon and oncoming sunrise...

      Bird recording >Bird song.mp3

      We continued our walk along the footpath, beside the 'hedgerows' to get a better vantage point for sunrise...

      Whilst awaiting sunrise I had time to check GONG to see what was happening... more specifically the 'hedgerow prom' from the previous day...

      A Blue Tit announcing 'sunrise!'.... Blue Tit.mp3

      My intention had been to head home for porridge and bed, but decided that I really did need to have another go at some solar imaging beforehand... J was not overly amused 'burning the candle at both ends', etc!

      On the walk back home, the frost descended...

      All photos just with an old iPhone6

      back home, set the gear up and whilst the Quark was warming, so was the porridge!

      Although I'm fairly new to solar imaging, I can see why solar imagers get up nice and early to grab the best seeing. I could see the difference coming into OACapture from my old DMK41 camera just how 'relatively still' the recording was (a QuickTime screen recording below).

      Untitled.MOV   Refreshed today, here is my first go at processing.
      Captured at 7.59am 45 seconds @ 15FPS (max) best 100 frames taken from 676. TSA102s / Quark Chromo / 0.5x Reducer
      Processed with a 'bag' flat and dark frame in AS!2 and ImPPG via Wine on a MacBook Pro. Finished in PsCC2017


      Updated Gong image from time of recording. Definitely want to get better and perhaps source a better camera - I have a thread in Equipment if any Solar folks would care to offer advice...

      New Recording 5.m4a New Recording 7.m4a Blue Tit.mp3
    • By TakMan
      Just a very quick process from today’s play. Will update this thread at some stage - been burning the candle at both ends... Was out imaging last night ‘til 2, then the wife decided that it would be a good idea to go out at 5.15 this morning to take in the dawn chorus! After an extra 2hrs back in bed, decided to get out in the sun and enjoy some solar imaging today. Now, as I type this, I’m outside imaging again!
      So sorting the best files and processing will have to wait until tomorrow! I also took the opportunity to take test shots through the dial settings of my Quark to see if I can work out where best to position it to.
      Here’s a quick one, not as good as I’d hoped, but there’s always a chance another will be better!
      The best 60 of 679

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.