Lunt drop the ITF in their Ha scopes??????

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Merlin66
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Lunt drop the ITF in their Ha scopes??????

Post by Merlin66 » Sat Aug 12, 2017 4:35 pm

I just read that Lunt have gone away from their ITF filters and now just use a "clear" IR filter.
Has anyone have experience of this latest development?
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Re: Lunt drop the ITF in their Ha scopes??????

Post by Solar B » Sat Aug 12, 2017 10:49 pm

That CN quote from Rikki actually dates back to 2013 ... but I didn't know either !


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Re: Lunt drop the ITF in their Ha scopes??????

Post by Bob Yoesle » Mon Aug 14, 2017 6:47 pm

Yes, Lunt doesn't use an ITF any more, and now use what appears to be a Schott BG series filter for near IR blocking and brightness tuning.

Lunt also moved IR blocking coatings to an RG630 substrate front or internal ERF, whereas the Coronado RG630 ERF only blocked UV, not IR. I believe the same holds true for the DayStar ERFS. That's why SolarSpectrum filters employ a Baader DERF for both IR and UV blocking.

I've been using Baader or Lunt IR blocking ERF's for awhile now, and so far none of my Coroando BF30's have had ITF deterioration for several years, whereas they failed quickly (within two years) with the non-IR blocked ERFs, likely due to thermal loading and cycling...
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