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CylonRed
Premium,MVM
join:2000-07-06
Bloom County

1 recommendation

Cool pics of the sun from a backyard..

»news.yahoo.com/photos/detailed-p···906.html



TheHarvester
Premium
join:2006-08-25
Dana Point, CA
kudos:3

Those are some nice pictures, thanks for the link.
I like solar observing and would also like to do some solar photography as well but it is expensive. A good solar telescopes or the good filters to convert a regular telescope that will display the granulation of the surface and solar prominences (flares jetting from the surface) cost in the thousands. I'm not quite ready to drop that kind of money for a telescope that does one thing.
--
mbsastronomy.com



rcroning
D700 Rocks
Premium
join:2005-05-21
Winnipeg, MB

1 edit
reply to CylonRed

Actually, you can buy a Coronado (Meade) PST for around $500. The next size up is about $1200 so they can be quite affordable. See this link »www.astro-nut.com/sun-pst.html

When you get to the 60mm and 90mm Coronados, and double stacked filters then yes, they can go for up to $7500!!!

On a pauper's budget one can do this. It's an image of mine of the Transit of Venus last year »/showpic/dimag···folder=0



jaykaykay
4 Ever Young
Premium,MVM
join:2000-04-13
USA
kudos:24
reply to CylonRed

About all I can say is wow. That sun doesn't look anything like what I am ale to see from my back yard! It almost doesn't look real. I am more than a pauper, so have nothing to do this with or even close, but I sure do enjoy seeing other's work.



toobright

@tmodns.net
reply to CylonRed

the images shown are often composited and complicated.

you can easily do simpler images of just sun disc and sunspots with the longest lens or lens setting you have and the darkest filter you have. try neutral density nd 4 or nd8 or nd 16 or nd 400 or whatever dark color filter you have. try stacking. and or double polarizers set to minimum.

to prevent sunburn the inside of your eye dont look long at the eyepiece image. even with filters the sun is too bright for safe viewing.



rcroning
D700 Rocks
Premium
join:2005-05-21
Winnipeg, MB
reply to CylonRed

ND or PL filters should NEVER be used for viewing the Sun...period. They do not provide any UV or IR protection. The only safe way is to use a solar filter designed for visual use and is usually double aluminized polyester such as the kind called Baader Planetarium Solar Filter material.

And images like these are sometimes stacked to get full focus from the nearest part of the Sun to the edges. The filters used are highly specialized. However, imaging with them is hardly complicated.

The "regular" solar filters only reduce the intensity of light but do not show any surface or edge detail except for sunspots.



toobright

@comcast.net
reply to CylonRed

here are links to the curves for some typical hoya / nikon etc filter glasses:

using the hoya / nikon names -

»www.hoyaoptics.com/color_filter/···_cut.htm

(the number is the nM at which transmission/blocking is 50%/50%, e.g R60 is 50% transmission at 600 nM.)

showing almost total transmission of invisible IR infrared in the 1800+ nM range -

»www.hoyaoptics.com/color_filter/···ting.htm

note that most glasses inherently block most UV,
but, as rconing notes,
many glasses can pass all of some wavelengths of invisible IR infrared light.

the visual band is roughly 400-700 nM,
UV is below 400,
IR is several octaves above 700.

again, if doing any photos of the sun with long lenses, avoid looking through the viewfinder at the magnified toobright image of the sun, which can instantly burn your eye inside.

in general, compare the size of the diameter of your eye iris, about 1/8" - 1/4", with the diameter of your telephoto lens, about 2"; the lens is collecting bout a hundred times more light, 100 times more bright, than your eye.

even the foil filters can have passbands in IR and be unsafe.

-
sunspot viewing and sunspot images are interesting cause you can use them to predict solar effects on earth, and you can use the movement of the spots to determine the rotational speed of the sun.