diaphragm

Frankenscope? Let's see it!***be advised that NOTHING in this forum has been safety tested and you are reading and using these posts at your own peril. blah, blah, blah... dont mess around with your eyesight when it comes to solar astronomy. Use appropriate filtration at all times...
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alessbonsai
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diaphragm

Post by alessbonsai »

Do you think this diaphragm for lamps might work for telescopes
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christian viladrich
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Re: diaphragm

Post by christian viladrich »

Hi,
What would be the use of the diaphragm ?
The only time I stop down the aperture of a telescope is for Ca K full-disk imaging. This is for reason of f-ratio and heat load.
This is no need for a diaphragm for this, only a piece of cardboard. On top of that I use white cardboard so it does not warm up when exposed to the Sun.


Christian Viladrich
Co-author of "Planetary Astronomy"
http://planetary-astronomy.com/
Editor of "Solar Astronomy"
http://www.astronomiesolaire.com/
alessbonsai
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Re: diaphragm

Post by alessbonsai »

These thoughts come when you've been locked inside the house under a cloudy and rainy sky for a month... I understood that it's all a game of diameter, f and length. I ordered a herschel apm, and after a 430nm filter and surely I will have to close the aperture of my refractor and I thought a mechanical diaphragm was more practical. I had already noticed the problem of wavelengths / diameter with the continuum filter, not excessively, but if closed from 80 to 70 or 60 it improves a little


christian viladrich
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Re: diaphragm

Post by christian viladrich »

In any case the price is reasonnable. Maybe I could use one, one of these days.
Thanks for pointing this !


Christian Viladrich
Co-author of "Planetary Astronomy"
http://planetary-astronomy.com/
Editor of "Solar Astronomy"
http://www.astronomiesolaire.com/
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