# Photographing the Sun



## boblalux (May 17, 2009)

I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?


----------



## KmH (May 17, 2009)

boblalux said:


> I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?


Do you just want a blob of light or do you want some detail like sunspots?


----------



## Josh66 (May 17, 2009)

I'm interested in this too...

I have a pair of solar binoculars (Coronado BinoMite II), I'd like to find the filter they have on them (white light solar filter, pretty much looks like a mirror; I'd also be interested in other solar filters too, H&#945; maybe) for my lenses.  No luck so far.

Something like this, but for a camera lens.


----------



## dxqcanada (May 17, 2009)

In Canada you can get threaded solar filters from EfstonScience

Manufacturer: Thousand Oaks Optical


----------



## Battou (May 17, 2009)

O|||||||O said:


> I'm interested in this too...
> 
> I have a pair of solar binoculars (Coronado BinoMite II), I'd like to find the filter they have on them (white light solar filter, pretty much looks like a mirror; I'd also be interested in other solar filters too, H&#945; maybe) for my lenses.  No luck so far.
> 
> Something like this, but for a camera lens.



I'd send a E-mail to Hoya offering it as a suggestion if they can not be found.


----------



## Josh66 (May 17, 2009)

dxqcanada said:


> In Canada you can get threaded solar filters from EfstonScience
> 
> Manufacturer: Thousand Oaks Optical


Thanks for the link.  Now that I know the part number to look for, maybe I can find one.



Battou said:


> I'd send a E-mail to Hoya offering it as a suggestion if they can not be found.



Not a bad idea, but I wonder how large of a market there would be for this?  They might not see enough money in it to start production...


----------



## Battou (May 17, 2009)

O|||||||O said:


> Thanks for the link.  Now that I know the part number to look for, maybe I can find one.
> 
> 
> 
> Not a bad idea, but I wonder how large of a market there would be for this?  They might not see enough money in it to start production...



That is a destienct possibility but, if no one shows an interest in something like that to beginwith the odds of it ever happining drop dramatically.


----------



## KmH (May 17, 2009)

O|||||||O said:


> I'm interested in this too...
> 
> I have a pair of solar binoculars (Coronado BinoMite II), I'd like to find the filter they have on them (white light solar filter, pretty much looks like a mirror; I'd also be interested in other solar filters too, H&#945; maybe) for my lenses. No luck so far.
> 
> Something like this, but for a camera lens.


Solar filters for telescopes are pretty specialized. You can get them so they transmit very specific wavelengths of light like just the hydrogen-alpha line.

But that is to see details of specific parts of the Suns upper atmosphere.

If I want an image of the current sunspot activity I just project an image of the Sun onto a dark background through a pinhole and photograph that.

By adjusting the pinhole to background distance I can control the size of the Suns image. That's essentially what they do at the McMath Solar Telescope on Kitt Peak. Their projected image is 3 feet across though.


----------



## LarryD (May 17, 2009)

There are plenty of good quality welders glass available to shoot through..


----------



## Dwig (May 17, 2009)

This isn't something a beginner could pull of, but it is something to strive towards:

The Online Photographer: Sic Transit

the post contains a link to a source for the appropriate filters.


----------



## Joves (May 17, 2009)

Thousnad Oaks is the best out there. I took this shot with my Coolpix 995 a few year agot through my telescope using a Thousands Oaks filter. Taken during an eclipse and I was luck to even get that shot that day because, the wind was bad as usual in Flagstaff.


----------



## astrostu (May 18, 2009)

I have a Thousand Oaks filter, too.


----------



## Josh66 (May 18, 2009)

Joves, what focal length telescope was that taken with?
(Just trying to get an idea what I could expect from my telescope.)

The moon is roughly the same apparent size as the sun in the sky, right?  Would it be safe to assume that the level of magnification I would get with the sun would be similar to photographing the moon with my telescope?


----------



## astrostu (May 18, 2009)

O|||||||O said:


> The moon is roughly the same apparent size as the sun in the sky, right?  Would it be safe to assume that the level of magnification I would get with the sun would be similar to photographing the moon with my telescope?



Yes.


----------



## Garbz (May 19, 2009)

boblalux said:


> I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?



Short answer: Don't!

Solar filters are very specific for a reason, much of what is emitted by the sun which is capable of damaging eyes is not in the visible spectrum. Polarisers are spectrally variant. The ones for photography do a great job for the visible spectrum but there is little data to how it handles infrared or UV light. This means when you look through them your pupils may dilate while not realising the very thing that could cause blindness has not been reduced. There have been plenty of cases of people going blind looking at solar eclipses by using photographic ND filters, or looking through floppy discs or that sort of thing. 

Do yourself a favour and get or build a solar filter, don't risk your eyesight.

The camera should be fine.


----------



## JerryPH (May 19, 2009)

Joves said:


> Thousnad Oaks is the best out there. I took this shot with my Coolpix 995 a few year agot through my telescope using a Thousands Oaks filter.



That is a pretty darn neat shot too.  I was at first thinking to myself "why??", your shot answered that for me quite fast.  I still prefer to take a shot of a person, but I can see the value.


----------



## JerryPH (May 19, 2009)

Garbz said:


> Short answer: Don't!  Do yourself a favour and get or build a solar filter, don't risk your eyesight.



That was in the back of my mind too.



Garbz said:


> The camera should be fine.



Would the sensor not be in danger of any kind from frying a few pixels or something?  I thought I read that somewhere


----------



## Gecko23 (May 19, 2009)

boblalux said:


> I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?



You definately want to use a filter that is explicitly intended for solar use, anything else is potentially going to lead to serious injury.

Coronado Instruments is a big name in solar scopes, filters, etc. They sell direct as well as through most of the major astronomical retailers. 

Another popular alternative among amateurs is the use of Baader film, also available at many retailers, to make your own filter. Its cheaper than coated glass filters, but far more fragile.


----------



## Joves (May 19, 2009)

O|||||||O said:


> Joves, what focal length telescope was that taken with?
> (Just trying to get an idea what I could expect from my telescope.)
> 
> The moon is roughly the same apparent size as the sun in the sky, right? Would it be safe to assume that the level of magnification I would get with the sun would be similar to photographing the moon with my telescope?


 Was taken through my 8" f/6 or 1220mm Newt with a 40mm eyepiece. I haver drilled holes in mine to move the mirror cell forward to shoot at prime focus when I built it. I like to shoot afocally. The best book to get for the set up is Edmunds Scientific's book All About Telescopes. It has been reprinted so many times and, sometimes they are out of it but, it is worth the wait.


----------



## Garbz (May 19, 2009)

JerryPH said:


> Would the sensor not be in danger of any kind from frying a few pixels or something?  I thought I read that somewhere



I thought normally yes but the wavelengths that typically do that are the visible as the glass in the lens would naturally cut a lot of UV, the dual polarisers would cut most of the visible, and then the infra-red would be taken care of by the sensor's own low-pass filter. So the parts which may damage the eye are taken care of in camera by other means.

Personally I wouldn't put this to the test though


----------



## dhilberg (May 20, 2009)

I found this for building a solar filter for an SLR lens:

How To Build a Solar Filter - The Galactic Fool


----------



## astrostu (May 20, 2009)

Just thought I'd mention that a solar filter usually blocks 99.999% of incoming light.  Do you want to risk relying on the glass to filter the UV, two polarizers to filter 99.999% of the visible, and the IR filter to block the IR ... or would you rather just get an actual solar filter?  It has been 6 years since E&M, but I'm pretty sure that the first polarizer blocks 50% of the light, and the next only blocks another 50% of that.


----------



## Garbz (May 21, 2009)

Err not quite. The polarising filter emits polarised light and the drop in output is due to the design of the polariser itself. Nice crystal polarisers used in photonic communcations for instance don't attenuate anywhere near 50% of the light.

But since the light is polarised the next filter will attenuate the light with direct proportionality to the filter angle. Thus if the filters are 90 degrees apart in theory all light is blocked in theory anyway.

But yeah, not good anyway.


----------



## boblalux (May 24, 2009)

KmH said:


> boblalux said:
> 
> 
> > I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?
> ...


 
Some detail - sunspots etc, Keith.
Sorry about taking so long to answer, had problems with the computer.
Bob


----------



## EhJsNe (May 24, 2009)

Well, if you want a sun star r whatever you call them, you can get pretty good result from 1/500 at f/22 at ISO 200. 
Dont ever look at the sun. I just take a burst and have the camera pointed at the sun, one shot out of 10 or 15 should be what I wanted!

If you want what everyone else is talking about....listen to them. I konw nothing about the sun, other than I just shouldnt look at it.


----------



## boblalux (May 26, 2009)

Thanks Garbz - how do I build a solar filter?
What about welders glasses?  I have a pair, and if I put both lenses together, it seems to adequately limit the lighting.
Bob



Garbz said:


> boblalux said:
> 
> 
> > I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?
> ...


----------



## Joves (May 26, 2009)

boblalux said:


> Thanks Garbz - how do I build a solar filter?
> What about welders glasses? I have a pair, and if I put both lenses together, it seems to adequately limit the lighting.
> Bob
> 
> ...


 You mean for when you are using a cutting torch or brazing. No they dont cut out that much light. Now you can use the glass for Arc welding. While not as good as a solar filter it is acceptable. I have used my old welding mask to look at partial solar eclipses and, never suffered any eye problems when doing that.


----------



## Garbz (May 27, 2009)

Yep the welders used for arc welding are sufficient as by design they protect the users from a very very wide range of light wavelengths.


----------



## sandratycova (Aug 28, 2009)

Yes, you can capture the photograph of Sun by reducing the strength of the lighting by using 2 semi-crossed polaroid filters but after you are taking a picture just visualize what you can see in that photo. If you want the photo of current sunspot activity then just pin your camera on darker side of the Sun.


----------



## Garbz (Aug 29, 2009)

sandratycova re-read the thread and DON'T! It's dangerous. There's no more to be said.


----------



## FrankLamont (Aug 29, 2009)

Also, I'd not, in future, (to Joves as well) take eclipses before the entire sun is covered. Looking at a partially covered sun can seriously damage your eyes as much as starting normally would. It's more dangerous, actually, because you can continuously stare at it.


----------



## FrankLamont (Aug 29, 2009)

Taking the sun, by the way, can and does damage sensors. Especially with a telephoto. Works like a magnifying glass.


----------



## Garbz (Aug 29, 2009)

True that, solar filters will fix that though.


----------



## Big (Aug 29, 2009)

sandratycova said:


> If you want the photo of current sunspot activity then just pin your camera on darker side of the Sun.


Good luck finding the "dark" side of the sun...


----------



## Plato (Aug 29, 2009)

boblalux said:


> I wish to photograph the Sun. Can I do this by reducing the strength of the lighting by using 2 semi-crossed polaroid filters?



I see that other responses have taken this objective in a different direction.  That's good.  Your thinking is correct and will work with the old linear polarizers.  Unfortunately, it will not work with modern "circular polarizers."  This is because the front surface of the polarizing filter does the polarizing (and eliminates reflections) while the rear surface scatters (or circularizes) the light (unpolarizes it) so that your auto-exposure mechanism will function properly.


----------



## Joves (Aug 30, 2009)

FriedChicken said:


> Also, I'd not, in future, (to Joves as well) take eclipses before the entire sun is covered. Looking at a partially covered sun can seriously damage your eyes as much as starting normally would. It's more dangerous, actually, because you can continuously stare at it.


 Ummm if you read my post it stated shot through my telescopes with a Thousands Oaks Solar filter. It is fully safe to shoot and, observed through a filter made for that purpose. 
 One exception to the solar filter rule is using supposed solar filters that go on the eyepieces. I dont think any manufacturers still provide those. Those have caused more eye damage that any others. WHen people would show me those and, ask if they were safe, I would drop them on the ground and, stomp them and, say now it is safe because ot os broken and, you cant use it. Filtration has to be at the front of any optics to be truly safe. And also has to be made for that purpose.


----------

