Solar filters - worth it or not?

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dimes
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Solar filters - worth it or not?

Post by dimes »

Hi guys,

I'm just curious as to how many of you own solar filters and whether it's worth it or not to buy one? I'm pretty clueless when it comes to observing the Sun. I own a pair of binoculars.
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Mariner
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Re: Solar filters - worth it or not?

Post by Mariner »

You can opt to DIY using the cheaper Baader Solar Film.
OCULARHOLIC ANONYMOUS!!!
Keep Calm and Carry on Observing.
dimes
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Re: Solar filters - worth it or not?

Post by dimes »

Mariner wrote:You can opt to DIY using the cheaper Baader Solar Film.
Hi Mariner, thanks for your reply! Anywhere in Singapore that I can get this solar film? Or if not, any recommended online sites to buy and learn how to DIY?
superiorstream
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Re: Solar filters - worth it or not?

Post by superiorstream »

Hi Dimes
Firstly you can take the sun in 4 colors namly
Ha (red),Cak (purple),540nm (green) and yellow (wide band)
The first three are narrow band and will involve filters costing
Thousands of dollars.
For beginners the option is the fourth one......yellow with
a thousand oak or orion glass filter.
Worth or not is a matter of opinion.You will get very dark
after exposure to the sun and may even lost one or two layers
of skin.However the sun is very dynamic when active and always
Offer very interesting view.........to say the least.
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antares2063
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Re: Solar filters - worth it or not?

Post by antares2063 »

Hi, I use a white light filter from Orion for my 80mm refractor . it enables me to see sunspot groups and granules at the edge of the solar disk, not sure if theres any for binos though.

regards,
Junwei
I miss the place where stars shine bright, to gaze upwards in awe of the sight
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Mariner
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Re: Solar filters - worth it or not?

Post by Mariner »

dimes wrote:
Mariner wrote:You can opt to DIY using the cheaper Baader Solar Film.
Hi Mariner, thanks for your reply! Anywhere in Singapore that I can get this solar film? Or if not, any recommended online sites to buy and learn how to DIY?
You can purchase the solar film from Astro Scientific at the Science Centre. Instructions for the DIY portion is in the website:

http://protecsolar.com/en/information/h ... lter-cell/

For Youtube instructions, I referred to this guy when I made mine:

http://youtu.be/rkJcIBPiYhM
OCULARHOLIC ANONYMOUS!!!
Keep Calm and Carry on Observing.
superiorstream
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Re: Solar filters - worth it or not?

Post by superiorstream »

Hi Dimes
Becareful.........a single layer of thin film may not be sufficient
and may result a super bright sun image that is dangerous to your
eyes.Safer to purchase ready made tested filters.Also part of the
solar radiation. ...uv and infra red.....are not visible but CAPABLE
OF BURNING YOUR RETINA IN NO TIME.If the aperture of your
Bino is large its advisible to stack say 2 uv and 2 infra red filters
with your normal solar filter .Also before using your eye to view
do try to use a camera to see its tooo bright.If so add more ND FILTRES.
MY 2 cents.Thanks.
Bomia
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Re: Solar filters - worth it or not?

Post by Bomia »

superiorstream wrote:Hi Dimes
Becareful.........a single layer of thin film may not be sufficient
and may result a super bright sun image that is dangerous to your
eyes.Safer to purchase ready made tested filters.Also part of the
solar radiation. ...uv and infra red.....are not visible but CAPABLE
OF BURNING YOUR RETINA IN NO TIME.If the aperture of your
Bino is large its advisible to stack say 2 uv and 2 infra red filters
with your normal solar filter .Also before using your eye to view
do try to use a camera to see its tooo bright.If so add more ND FILTRES.
MY 2 cents.Thanks.
It is interesting to know that 1 layer may be insufficient. So is there any way to know that when we need to add a layer? Like anything we can take reference or when certain sign to take note?
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cloud_cover
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Re: Solar filters - worth it or not?

Post by cloud_cover »

Hello!
The great thing about solar observing is never, never cut corners and try to cheap out. Permanent damage may occur instantly if any of your equipment is insufficient or fails while observing.
If you're going to do solar, then I strongly suggest use well established equipment of good repute.
The Baader Solar film is designed for single film use, as far as I know. They even have (relatively) cheap mounted films in a simple cell for various apertures or you can buy a roll of film for much cheaper, per unit area. If you do that though, you must ensure that the film is very securely affixed to the FRONT END of your telescope. Failure to do so may result in permanent blindness if the film falls off or otherwise fails while you are observing the sun.
Do not use "Sun X", "V Cool" or any other form of solar film not explicitly designed for solar observation. Firstly even if you stack multiple films to make the sun dim enough to comfortably observe, unless you are very sure of the IR and UV transmission (despite what the manufacturer says), these invisible wavelengths can still burn your retina. The first sign of trouble you'll see is a permanent imprint of the sun in your visual field. Not pleasant.
Popular manufacturers of white light solar filters are Baader and Thousand Oaks. This item is designed for binocular use, I believe.
Also, never, never use rear or eyepiece mounted solar filters without front protection because these filters will take the full brunt of focused solar energy and will fail. In the past cheap "solar eyepieces" were sold and they had the unnerving tendency to crack under the heat stress. Instant failure = instant blindness. There are however high end viewing devices intended to be affixed to the rear of a telescope. Examples of such rear mounted viewing aids include Herschel Wedges and Daystar H-Alpha filters. Even then, you'll find strict guidelines on the use of energy rejection filters based of telescope design and aperture for these items. There are, however, not designed for binocular use.
A note about H-Alpha observing: Dedicated solar H-Alpha filters are much more expensive than the equivalent night time H-Alpha filters used for narrowband astrophotography. This is because a solar H-Alpha filter has a bandpass an orders of magnitude smaller than the night filter, in order to safely permit viewing. Using a nighttime filter will be dangerous to your eyes so do not do it!
Solar observing is lots of fun because the sun is a dynamic object. Only thing is its a very, very hot hobby so bring a big water bottle! Oh, and if you're using binos, make sure the eyeguards completely shade your eyes so you don't inadvertently stare at the sun. Most of us use a telescope (be it a front filtered telescope or a dedicated solar scope) with a diagonal so that our eyes look 90° away from the sun
All the best! :)
DON'T PANIC
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