# Use of solar eclipse filter once the eclipse is done



## motorhead9999 (Aug 14, 2017)

So I purchased a Lee solar eclipse filter (it's like a 16 or 18 stop), and I was just thinking of after the eclipse. I spent $150 bucks on this filter, and the thought of getting some use out of it aside from waiting another 6 or so years for the next eclipse became very appealing to me. In reading the documentation though, they state that the filter isn't suitable for daytime long exposure. Can anyone explain to me why that's the case?


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## SecureGSM (Aug 14, 2017)

You may consider the following page:

https://www.dpreview.com/forums/thread/4181486#forum-post-59852580




motorhead9999 said:


> So I purchased a Lee solar eclipse filter (it's like a 16 or 18 stop), and I was just thinking of after the eclipse. I spent $150 bucks on this filter, and the thought of getting some use out of it aside from waiting another 6 or so years for the next eclipse became very appealing to me. In reading the documentation though, they state that the filter isn't suitable for daytime long exposure. Can anyone explain to me why that's the case?


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## stevelee (Aug 14, 2017)

motorhead9999 said:


> So I purchased a Lee solar eclipse filter (it's like a 16 or 18 stop), and I was just thinking of after the eclipse. I spent $150 bucks on this filter, and the thought of getting some use out of it aside from waiting another 6 or so years for the next eclipse became very appealing to me. In reading the documentation though, they state that the filter isn't suitable for daytime long exposure. Can anyone explain to me why that's the case?



I took some pictures of the sun this afternoon. So the filter can be used to photograph the sun or anything else as bright as the sun. Relatively few things on earth are that bright, however.

And my pictures of the sun did not show any detail, although I bracketed exposures over a wide range. I don't know whether my equipment would get detail on the sun at a time of more sunspot activity.

I also took some fairly interesting pictures as clouds moved in front of the sun. Instead of the 1/200 second exposure of the sun photo, the cloud photo was shot at 5 seconds. Both were shot at f/8.

Other than that, unless you are willing to spend time and money chasing eclipses around the world, you are not going to get a lot of use out of your filter in the US.


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## Mt Spokane Photography (Aug 14, 2017)

I don't plan to photograph the sun, so my filter will be useless to me. I did buy before the prices rocketed, so I just considered it a expense not a investment.


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## Valvebounce (Aug 14, 2017)

Hi Folks. 
Seems to me the best bet would be to sell these filters unless solar photography piques your interest following the eclipse. 
Perhaps targeted adverts taken out in the areas where the next solar eclipse is due, July 2nd 2019 S Pacific, Chile, Argentina (plenty of time to organise a carrier (pigeon ;D ;D)). 
If I thought for one moment I might make it to 23rd Sept 2090 I'd buy one! : ;D 

Cheers, Graham.


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## ethanz (Aug 14, 2017)

That is why they say on BH: Solar filters are not returnable after August 21 ;D


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## LDS (Aug 14, 2017)

motorhead9999 said:


> Can anyone explain to me why that's the case?



The Sun looks quite "monochromatic" therefore a solar filter doesn't need to deliver a proper color balance of a generic image. The main aim is to reduce brightness and cut dangerous wavelengths. Thereby some filters deliver a "white" image (the actual Sun is quite whitish), other a "yellow" or "orange" one, depending on how they are built and why, but outside Sun imagery they may be really disappointing.


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## bholliman (Aug 14, 2017)

LDS said:


> ... outside Sun imagery they may be really disappointing.



I've invested $110 in solar filters that hopefully I can use again in 2024, but who knows... If I can capture some really good images, its money well spent. If its cloudy or I mess up, probably no!

They are getting plenty of use now in practice for the eclipse, but I doubt they get used again when its over, at least not for 7 years.


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## stevelee (Aug 14, 2017)

The problem for me is that my filter is 58mm. That fits several of my lenses, but is of no use on any of the shorter ones. The 75-300mm lens it fits is not very good, particularly at 300mm. I posted some test shots on a 6D2 thread with regard to the usefulness of a flippy screen. I don't know how much of the bad quality can be attributed to the filter, how much to the less than stellar lens, how much to user incompetence, and how much if any to the T3i upon which it was mounted. If we have some more sunny weather before Monday, I'll try some sun shots between f/11 and f/16, where somebody's curve shows the lens to be a little sharper.

So if I'm still alive and somewhat coherent of mind and in good enough health to travel, even if my friend in Dallas is alive and well and still in his own home where I can be a house guest, I would hope by then that I would have a somewhat better telephoto lens. Odds are, it won't take a 58mm lens.

I might as well add the picture here, where it is a little more relevant than on the 6D2 thread. This is the full frame reduced for posting. The original at 100% didn't look any better.







I tried focusing manually on the screen. I may see if autofocus does any better. I have taken passable shots of the moon with the same lens at 300mm (480mm crop equivalent).


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## motorhead9999 (Aug 15, 2017)

When you tried focusing manually, did you zoom in on the sun in the screen? Usually the screens have a 10x or so zoom feature on the screen (I know my 6D does), so you should be able to get a decent enough focus there.


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## bholliman (Aug 15, 2017)

stevelee said:


> I tried focusing manually on the screen. I may see if autofocus does any better. I have taken passable shots of the moon with the same lens at 300mm (480mm crop equivalent).


The fuzziness looks like a focus issue to me, I was getting similar results early in my practice. 

Shooting the sun is more difficult than I imagined, especially with my 5DsR without a tilting LCD (my M5 works very well thanks to the tilt LCD). In bright sun, its really difficult to see the LCD to focus in live view or do anything else. I've been using a small dark blanket over my head and the camera so I can see well enough to focus and adjust the camera settings. I've found that LV autofocus works pretty well on the edge of the sun, both with and without 10x magnification. I've also had success pre-focusing on a distant object/hill over a mile away and using gaffers tape to immobilize the manual focus ring, essentially locking it in place. 

Good luck!

Update:

This is a shot from today with my 5DsR and 100-400 II at 400mm, cropped heavily. Today I experimented with using Av mode and letting the camera's autoexposure do its thing. First in Evaluative then Partial and finally Spot exposure modes. None of them worked very well, Spot did the best at -3 EC. I plan to use full Manual mode on the 21st at this point. This was shot at f/5.6, 1/250, ISO320 using a B&H solar filter.


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## stevelee (Aug 15, 2017)

motorhead9999 said:


> When you tried focusing manually, did you zoom in on the sun in the screen? Usually the screens have a 10x or so zoom feature on the screen (I know my 6D does), so you should be able to get a decent enough focus there.



Good point. I'll try that with my next tests. I knew one could do that, but sunlight was so fleeting that I didn't try to learn too many new things in the short time I had. I have not used live view very much with that camera. Also, if I get to photograph the eclipse, the line of the moon's shadow should help in focusing. The weather forecast for next week is not encouraging, however. 

Something I did learn in that test would be to wear a dark shirt. Even though I had the flippy screen down in the camera's shadow and I had on a ball cap, the reflection off my light yellow shirt made the screen harder to see. I may even try putting a black cloth over my head and the screen, like view camera folks. I know I have some black t-shirts I could use.

Thanks for the suggestion.


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## stevelee (Aug 15, 2017)

bholliman said:


> The fuzziness looks like a focus issue to me, I was getting similar results early in my practice.
> 
> Shooting the sun is more difficult than I imagined, especially with my 5DsR without a tilting LCD (my M5 works very well thanks to the tilt LCD). In bright sun, its really difficult to see the LCD to focus in live view or do anything else. I've been using a small dark blanket over my head and the camera so I can see well enough to focus and adjust the camera settings. I've found that LV autofocus works pretty well on the edge of the sun, both with and without 10x magnification. I've also had success pre-focusing on a distant object/hill over a mile away and using gaffers tape to immobilize the manual focus ring, essentially locking it in place.
> 
> Good luck!



Thanks. Just knowing that someone else found this as hard to do as I have is encouraging. I did crank up the LCD brightness before I tried those tests. I don't think the lens is robust enough to hold the focus if I take off the filter and focus on something distant and then put the filter back on. Maybe we can get a little sunshine the next few days while I'm not otherwise busy, and I can try more things.


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## Talys (Aug 15, 2017)

stevelee said:


> I took some pictures of the sun this afternoon. So the filter can be used to photograph the sun or anything else as bright as the sun. Relatively few things on earth are that bright, however.



I think we can safely remove the qualification... On/From Earth, there is nothing as bright as the Sun  Not even a nuclear blast. There are some things which are brighter in a relatively small area. Some lasers, on one extreme - as long as it's pointed right at the camera sensor.

I wonder what kind of magnification/filter is needed to capture events like solar flares.


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## SecureGSM (Aug 15, 2017)

well, how about arc welding?  could be a great photography subject

Article by B. Ralph Chou, MSC, OD, on NASA Goddard's website

"... *One of the most widely available filters for safe solar viewing is shade number 14 welder's glass, which can be obtained from welding supply outlets.* A popular inexpensive alternative is aluminized mylar manufactured specifically for solar observation. ("Space blankets" and aluminized mylar used in gardening are not suitable for this purpose!) Unlike the welding glass, mylar can be cut to fit any viewing device, and doesn't break when dropped. ..."

https://umbra.nascom.nasa.gov/eclipse/990811/text/eye-safety.html








Talys said:


> I think we can safely remove the qualification... On/From Earth, there is nothing as bright as the Sun  Not even a nuclear blast -- though I think a hydrogen bomb is about as bright in a small area, for a brief moment.
> The exception would be if you make it a very, very tiny area: you could shoot a pulsed laser directly at the camera, which would technically be brighter than the sun -- were the beam to hit the camera's sensor directly


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## stevelee (Aug 15, 2017)

bholliman said:


> The fuzziness looks like a focus issue to me, I was getting similar results early in my practice.
> 
> Shooting the sun is more difficult than I imagined,



Thanks again. The sun came out for a bit this afternoon, and I tried some more shots, starting from the assumption that the problem before was mainly a focus problem.

The quickest thing I learned was that being out in the sun in August in North Carolina with a black t-shirt over your head gets uncomfortable very fast. But it does help focus using the screen. I tried autofocus, and the camera went wild and seemed to display the corona briefly and arrived somewhere odd. So I turned that off, put the t-shirt over my head, and focused manually from the screen.

I had found somebody's lens tests, and their charts suggested this lens is at its best somewhere between f/11 and f/16. That should help the focus issue, too. So I took a bunch of pictures at f/14, some at f/16, and for grins a few at f/32 and f/45, at various shutter speeds between 1/1000 and 1/30. The overexposed ones seemed to mask the CA better. The darker ones appeared to show a bit of detail. I suspect most of that is noise, but I was not successful with stacking in Photoshop and seeing anything useful from the difference, etc., modes. The apparent sunspot on the upper left is apparent in all the shots that aren't way too dark or way too bright. Since the pictures were shot over a period of 16 minutes and different parts of the sensor were used at different times, that makes me reasonably sure that wasn't an artifact of the sensor or lint on the filter. And thus I suspect that it was in good focus and that the filter is not bad.

Here is a full-size crop of a shot at 1/320 sec. f/16 ISO 200 manual focus AWB. I did no adjustments in camera raw, and did just the crop in Photoshop and saved as a JPEG:


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## Talys (Aug 16, 2017)

SecureGSM said:


> well, how about arc welding?  could be a great photography subject



Haha cool! Touche!


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## Mt Spokane Photography (Aug 16, 2017)

I did sell 4 sets of Celestron Solar Glasses that were part of the package deal along with my Maurmi Solar Filter. I got $40 for them, and had several people wanting them. I still have 5 Orion Solar glasses, enough for the family. 

That cut the cost of my filter exactly in half, so I'll only lost $40 if it is never used again.


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## bholliman (Aug 17, 2017)

stevelee said:


> The quickest thing I learned was that being out in the sun in August in North Carolina with a black t-shirt over your head gets uncomfortable very fast. But it does help focus using the screen.



No kidding! I was just out doing some practice shooting during my lunch hour with blanket over my head -
it wasn't fun! (90+ and humid here). I suppose I could invest in a Hoodman loop, but I doubt I would use it again, so really can't see spending the $90 or so for a one-time event.



stevelee said:


> I tried autofocus, and the camera went wild and seemed to display the corona briefly and arrived somewhere odd. So I turned that off, put the t-shirt over my head, and focused manually from the screen.
> 
> I had found somebody's lens tests, and their charts suggested this lens is at its best somewhere between f/11 and f/16. That should help the focus issue, too. So I took a bunch of pictures at f/14, some at f/16, and for grins a few at f/32 and f/45, at various shutter speeds between 1/1000 and 1/30. The overexposed ones seemed to mask the CA better. The darker ones appeared to show a bit of detail. I suspect most of that is noise, but I was not successful with stacking in Photoshop and seeing anything useful from the difference, etc., modes. The apparent sunspot on the upper left is apparent in all the shots that aren't way too dark or way too bright. Since the pictures were shot over a period of 16 minutes and different parts of the sensor were used at different times, that makes me reasonably sure that wasn't an artifact of the sensor or lint on the filter. And thus I suspect that it was in good focus and that the filter is not bad.
> 
> Here is a full-size crop of a shot at 1/320 sec. f/16 ISO 200 manual focus AWB. I did no adjustments in camera raw, and did just the crop in Photoshop and saved as a JPEG:


Your focus looks pretty close here. My AF goes crazy unless my focus point in LV is picking up the edge of the sun, in the center there is no detail to focus on.

I've been shooting at f/5.6, wide open with my 300mm f/2.8 + 2x extender with pretty good results. The e-book I read recommended f/4 to f/8 as wider apertures will keep you ISO down during totality. I'm planning to use ISO 400 and f/5.6 during totality so I can keep my shutter speeds under 1/4 second, to avoid the earth's movement being picked up by a slower shutter speed. This is using the recommended setting in the book, but if there is any partial cloud cover higher ISO or slower shutter speeds will be required.

Today was my final practice and it went pretty well. I've been through it enough to have the steps down, but who knows what will happen in the excitement of the moment. Good luck with your practice and actual event shooting!


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## stevelee (Aug 17, 2017)

bholliman said:


> Good luck with your practice and actual event shooting!



Thanks. The last forecast I saw for Monday predicts a sunny day here and cloudy in the town in SC where I am considering going for totality. The traffic south of here on a Monday morning is impossible even with no eclipse. I may decide to stay home and photograph the 97% from the (relative) comfort of my driveway rather than trying to brave the traffic to try to get less than two minutes of totality. I realize that 97% will be nothing like those moments of totality if visible of even if the obscured sun is behind a cloud.


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## ethanz (Aug 17, 2017)

What is the difference between 100% and 97% totality? (Or say 87% Obscuration like where I live)


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## stevelee (Aug 17, 2017)

ethanz said:


> What is the difference between 100% and 97% totality? (Or say 87% Obscuration like where I live)



I've never experienced 97% to be sure, but just from a photography standpoint there would be a lot of difference. You never take off the solar filter. You don't see/photography Bailey's beads. You don't see the corona or earthshine. You still shouldn't look at the sun without the glasses even at 97%.

From an experiential perspective, the sky gets darker, but not that dark. At 100% it gets very dark, I understand. Either way, birds will start acting like it's time to roost and then to wake up. 

The eclipse I remember seeing (projected by pinhole on a piece of paper) must have been the 1984 annular eclipse, based on where I was living at the time. I was about 75 miles east of the narrow band where it was truly annular. I don't know what percentage it would have been called where I was, but it cut out a good chunk of the sun at maximum. The sky did get darker and the birds made noises. It was still pretty neat. This one should be better from where I live now. But that is a difference of degree. I think totality is more like a difference of kind, in terms of experience.

It will be a tricky call for me as to what to do (or try to).


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