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Fixed % density filter?

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#1 39.1N84.5W

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Posted 27 July 2019 - 12:57 PM

In my observing setup I use a 2" filter slide and high power binoviewing.
I'm looking at buying a fixed neutral density filter like 25%, 50%, or 75%. Which one do you use the most?

#2 junomike

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Posted 27 July 2019 - 01:01 PM

Depends on the size of the OTA being used (14" requires more the 8" to equal brightness).

The 25% should do well for the 8" SCT

For multiple OTA's I found a variable Polarizer best as It can be set from 0% - full and anywhere in between.

I used it on the Diagonal nose-piece which requires trial/error to get right.



#3 vtornado

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Posted 27 July 2019 - 01:56 PM

For a 10 inch dob, I use a 25% filter.  The 13% is too dark.  I only have to use the filter if panning around at medium power.

High power is comfortable enough when I get to 1mm exit pupil or below.  I bought a variable polarizer thinking maybe polarized light would allow me to see more  detail over a simple ND.   It doesn't



#4 39.1N84.5W

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Posted 27 July 2019 - 06:53 PM

I'm using a 8" refractor.


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