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Solarmax 60 (pre meade)

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#1 Daniel

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Posted 22 February 2019 - 12:53 AM

This may be a dumb question...but here goes.
Is it possible to remove the rear diagonal and insert a dslr... While leaving the front ha etalon on and using it for deep sky astrophotography?
Or is the filter in the diagonal the actual ha filter that is used for night time photography.
I was just pondering the thought and wondered if anyone has done this...if it is even possible.

#2 Oldfield

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Posted 22 February 2019 - 01:33 AM

Etalon alone, will pass H-alpha and many other wavelengths, so it's not useful.  

 

The blocking filter (in the form of a diagonal), will filter out the other wavelengths (second, third, ... harmonics)



#3 Daniel

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Posted 22 February 2019 - 08:48 AM

So...a double stack etalon does what exactly... IF you were to use it alone with dslr at night.
What is its purpose...is it a tuner only? And it does not have any nb blocking of any sort?

#4 vincentv

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Posted 22 February 2019 - 11:38 AM

I'm by no means an expert but here's my take:

The front glass will work as a red #25 filter, i.e. let through all light from ~620nm and above.

The etalon itself will provide a sawtooth pattern which will behave mostly as a neutral density filter. It will attenuate the image over a large spectrum. The main use of the blocking filter is to isolate one of the etalon's transmission peaks.



#5 Daniel

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Posted 22 February 2019 - 05:02 PM

Thank you both for the info.


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