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blue and yellow make green?

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#1 cpsTN

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Posted 18 July 2019 - 03:42 PM

just received a #82A blue and already had a #8 yellow. If I put them together, will it be a "#90 green"?

lol.gif lol.gif lol.gif 

Seriously though, approximately what wratten number green is that combination? I know it is noticeably lighter than #56.

 

I am going through options to photograph the Sun in several "pastel" colors for the Mercury transit in November.


Edited by cpsTN, 18 July 2019 - 03:44 PM.


#2 Frisky

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Posted 18 July 2019 - 03:46 PM

LOL! I've been stacking those two for a clean view of the planets through my refractor. I don't really see any green tint, just some glare reduction and meager contrast boost. 

 

Joe



#3 cpsTN

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Posted 18 July 2019 - 03:56 PM

The #82A is a very light blue and does boost contrast but I can see a noticeable green when stacking them. Now, that is when they are not attached to the scope, just looking through them with the naked eye. Just got the #82A today, amid thunderstorms, so I haven't been able to tell.

 

Do you know if there is a blue between #82A and #80a? I have always thought #80A was way too blue. Don't tell me ...#81A. LOL



#4 helpwanted

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Posted 18 July 2019 - 04:10 PM

nice font size!


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#5 ButterFly

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Posted 18 July 2019 - 05:38 PM

The PDF for the Orion filter set is a good visual reference when mixing the Wratten filters.  It shows representative spectra for the various filters as graphs.  It appears as though the combination would give a #56 light green type with less blue and higher transmission.

 

A more complete table version can be found here.  You can just multiply the respective transmissions (as percentages) at each wavelength to get the combined transmission.

 

Honestly though, just stacking them and seeing whether they work nicely is usually easier.  You can even do that after the eyepiece for a quick check before you take off the eyepiece and screw one, the other, or both on.  The charts and graphs are better for finding totally incompatible pairs where the spectrum of one kills a large part of the other.



#6 cpsTN

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Posted 18 July 2019 - 06:17 PM

Thank you for all the information. I will look at those things and see. I would like to have one of each routing number just because I like to collect different colored things. I think in my heart I'm 6 years old. lol

 

As far as the font size, I posted this from my desktop computer at home and for some reason I have more trouble reading it on the computer screen and I do on my phone I didn't realize it was going to be so big on the smaller screen. Or at least that's the way I'm receiving it anyway. 




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