View Full Version : 10 Stop Neutral Density Photography, the cheap alternative.
tkerr
11-22-2010, 07:48 PM
I've been following a thread discussion at POTN forums about using a #10 glass filter lens for a welders helmet.
http://photography-o...ad.php?t=767152 ("http://photography-on-the.net/forum/showthread.php?t=767152)
So I decided to experiment with it myself, what the heck, the glass
filter only cost $4.98 at Lowes. I contrstucted a holder to slide
onto the end of my camera lens that allows me to slide the glass filter
in and out. ND filters are great for a lot of things, especially
water falls, the surf zone at the beach and clouds just to name a few. Today I've got a few thin clouds hanging around on
an otherwise sunny afternoon.Went outside and set it up to test it
out and this is what I got.
Not really that interesting, but at
least I know it's potential.Can'twait to get out to the beach with
this to see what I can do.
Oh, And btw, it does take some post processing, otherwise all you will have is a green picture.
ISO 100, f/16, 60 second exposure, on a bright sunny mid-afternoon.
http://api.photoshop.com/v1.0/accounts/e308b554104a49c9973e1e35131b193c/assets/044a1523915c42b0b4d16bc3a449c468/renditions/1024.jpg?md=1290457012000
One thing's for sure. I can see that it is time to clean the dust off the sensor again.
The Before Post Processing image
http://api.photoshop.com/v1.0/accounts/e308b554104a49c9973e1e35131b193c/assets/4122fd0dcfa74a4893b5e223190f4ce2/renditions/1024.jpg?md=1290459297000
Sheiky
11-22-2010, 08:13 PM
Oh, And btw, it does take some post processing, otherwise all you will have is a green picture.
The first thing that came in mind was that the glass in any of the welding masks I used isn't ...uh "neutral" ...as far as color is concerned.
But still the idea is pretty good [:)] They should call it 10 stop Density Filters instead of Neutral Density though [;)]
And obviously you need to have quite some photoshopping skills if you shoot something with a lot of different colors in it. Or it must work very well in black and white or monotone colors [A]
tkerr
11-22-2010, 08:36 PM
And obviously you need to have quite some photoshopping skills if you shoot something with a lot of different colors in it. Or it must work very well in black and white or monotone colors /emoticons/emotion-13.gif
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Actually all you really need to do is adjust the tint, and then a slight color temp adjustment, maybe a little contrast adjustment also, all of which I would think could be done in most any photo editing software.
wickerprints
11-22-2010, 11:10 PM
The problem with uneven density response as a function of wavelength is that you can clip your highlights in one or more channels without achieving adequate exposure in the other(s). For example, if the filter has a 10-stop density in the red and blue frequencies but, say, only 6 stops of density in green, then it becomes improbable to expose the sensor in such a way that would allow faithful capture of all three channels at once.
That
tkerr
11-22-2010, 11:42 PM
The problem with uneven density response as a function of wavelength is that you can clip your highlights in one or more channels without achieving adequate exposure in the other(s). For example, if the filter has a 10-stop density in the red and blue frequencies but, say, only 6 stops of density in green, then it becomes improbable to expose the sensor in such a way that would allow faithful capture of all three channels at once.
That's why ND filters are expensive--it is easy to make a material that blocks a lot of light, but not so easy to do it in a way that is roughly uniform across the visual spectrum.
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Technical perfection is not the point of this. That is obvious, so I thought. It Is Just An Alternative! A $4.98 Alternative for which no one should expect miracles. It's not like everyone has a daily use for a ND filter, and it is for that reason I have no desire to spend the money on one. This is just something that can be fun for someone to play around with and not have to spend a lot of money to do it. That's all, and it is cheap, and does have potential uses no matter how Technically inaccurate it might be. It's not meant to produce professional level technically perfect silky smooth waterfall photos for publication. It is something that people can do without forking out all kinds of money for a filter they will rarely use.
Does every picture have to achieve technical perfection? Can't it just be visually appealing to someone instead?
PaulM
11-23-2010, 09:47 AM
If you took a B&W of a waterfall amongst verdant green foliage would you get a nice very smooth and bright waterfall AND bright foliage?
Wondering about creative use of the green tint...
Paul.
Sheiky
11-23-2010, 01:26 PM
Does every picture have to achieve technical perfection? Can't it just be visually appealing to someone instead?
Oh yes it can and I like the idea of a do it yourself ND filter. However you wouldn't technicallybe able to call it an "alternative" to a "real" ND filter would you, since it has different characteristics.
Anyway I think it could really make up some creative shots. When I started thinking about it: could the window tinting foil that is used in car-tuning work as such an ND filter as well? You could apply it onto a cheap filter and so make your own ND filter which can be easily mounted and unmounted.
Looking forward to see some better footage from your home-made ND filter. See if I can be convinced to do the same myself [A]
tkerr
11-23-2010, 03:46 PM
If you took a B&W of a waterfall amongst verdant green foliage would you get a nice very smooth and bright waterfall AND bright foliage?
Wondering about creative use of the green tint...
Paul.
Almost anything is possible with Photoshop. You could just shoot it in color, convert it to B&W and use the history brush on the foliage.
However you wouldn't technically be able to call it an "alternative" to a "real" ND filter would you.
Technically, by definition Yes it can be called an alternative. " Substitute, Different, other, choice between two or more things = Alternative" [;)] [H]
Anyway I think it could really make up some creative shots. When I started thinking about it: could the window tinting foil that is used in car-tuning work as such an ND filter as well? You could apply it onto a cheap filter and so make your own ND filter which can be easily mounted and unmounted.
Hmmm,[^o)] I don't know how well that would work because the way you are applying the window tint so that it will adhere to the glass. But then why would you need to apply it to anything?
In amateur astronomy we use a Mylar film as a white light filter to observe or image sun spots; It's not applied to any kind of glass. Some people buy or make holders of some kind, while others just wrap it around the end of the lens and hold it in place with a rubber band.
wickerprints
11-23-2010, 04:57 PM
Just to clarify, I
tkerr
11-27-2010, 07:02 PM
I went to the beach today hoping to see some wave action and test out this welders mask filter. But when I got there the seas were relatively calm with small 1 to 3 foot, long interval waves. I should also have gone earlier in the morning or waited until later this afternoon when the Sun isn't so high and bright.
Anyways, this is what I got. 60 seconds, ISO 100, f/16
http://api.photoshop.com/v1.0/accounts/e308b554104a49c9973e1e35131b193c/assets/57c24113139844768ae923bf20dce56b/renditions/1024.jpg?md=1290892040000