Do you think this diaphragm for lamps might work for telescopes
diaphragm
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Re: diaphragm
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.
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/
Co-author of "Planetary Astronomy"
http://planetary-astronomy.com/
Editor of "Solar Astronomy"
http://www.astronomiesolaire.com/
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Re: diaphragm
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
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Re: diaphragm
In any case the price is reasonnable. Maybe I could use one, one of these days.
Thanks for pointing this !
Thanks for pointing this !
Christian Viladrich
Co-author of "Planetary Astronomy"
http://planetary-astronomy.com/
Editor of "Solar Astronomy"
http://www.astronomiesolaire.com/
Co-author of "Planetary Astronomy"
http://planetary-astronomy.com/
Editor of "Solar Astronomy"
http://www.astronomiesolaire.com/