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Stripping the coating off lenses


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#1 Dan Salzmann

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Posted 20 March 2007 - 05:56 PM

Have heard several people mention that this is done for flare effects and was wondering how this is done.
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#2 Nick Mulder

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Posted 20 March 2007 - 09:59 PM

Clean it vigourously with your favorite aviation fuel, remove all lenshood-esque parts, chip the front element, point at sun :ph34r:
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#3 Kenny N Suleimanagich

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Posted 20 March 2007 - 10:45 PM

ultrafine-woven lint-free cloth with Brasso, be VERY careful to be even because Brasso can eat through the glass too. So: Use minimal Brasso, be even with it, when youre done dry it all off and clean with lens fluid and tissue.
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#4 Nick Mulder

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Posted 20 March 2007 - 11:38 PM

In reality, I'd say just buy/find an older non-coated lens rather than hacking a new one
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#5 Leo Anthony Vale

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Posted 21 March 2007 - 02:09 PM

ultrafine-woven lint-free cloth with Brasso, be VERY careful to be even because Brasso can eat through the glass too. So: Use minimal Brasso, be even with it, when youre done dry it all off and clean with lens fluid and tissue.


Don't forget to disassemble the lens to do the inner surfaces.
Those internal reflections account for most of the flare.

& recalibrate the T-stops.
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#6 Nick Mulder

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Posted 21 March 2007 - 02:12 PM

Don't forget to disassemble the lens to do the inner surfaces.
Those internal reflections account for most of the flare.

If you are going to go that far you could paint the barrel internals white at the same time :lol:
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#7 boy yniguez

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Posted 22 March 2007 - 06:23 PM

If you are going to go that far you could paint the barrel internals white at the same time :lol:

leo meant internal reflections among the elements! painting the inside of the barrel white would if anything lower the contrast not produce more flare.
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#8 Nick Mulder

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Posted 22 March 2007 - 07:17 PM

maybe my definition of flare is different from yours - I really have never looked it up exactly - but yep, I understand what you are saying ...

I have a lens here I was considering turning into the flare beast just out of interests sake... might even install some mirror/reflective surfaces inside it - I think a specular reflection would yield more direct flariness than the white, which yes would just produce a low con lens (the two often come hand in hand anyway)

Its bored project # 16 - wont get done for months
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#9 Leo Anthony Vale

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Posted 24 March 2007 - 12:25 PM

leo meant internal reflections among the elements! painting the inside of the barrel white would if anything lower the contrast not produce more flare.


As I understand it flare also lowers the contrast. Those internal reflections wind up putting random light into the shadows thus lowering the contrast.
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#10 boy yniguez

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Posted 30 March 2007 - 10:12 AM

As I understand it flare also lowers the contrast. Those internal reflections wind up putting random light into the shadows thus lowering the contrast.

yes, leo but not always! i've encountered flares that created ghost images on small sections of the image, not an overall drop in contrast!
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#11 Leo Anthony Vale

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Posted 31 March 2007 - 12:41 PM

yes, leo but not always! i've encountered flares that created ghost images on small sections of the image, not an overall drop in contrast!


I didn't say that was the only the only thing. I suppose it's the least dramatic effect of flare. Usually from shooting something contrasty or back lit, but with no extremely bright highlights like a head light, a fire or the sun.
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#12 Nick Mulder

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Posted 31 March 2007 - 03:36 PM

yes, leo but not always! i've encountered flares that created ghost images on small sections of the image, not an overall drop in contrast!


Were you using filters not as practibily close to being %100 parallel to the film plane ? (like you'd expect the rest of the elements would be) -

I got heaps of ghosting from using ND filters in front of my lenses they were the Cokin resin type and weren't perfectly straight and therefore mounted on a noticeable angle - the ghosts are always there but any high-con scene will dramatically increase the visibility of an actual ghosted image - after fiddling with the bracket whilst looking through the viewfinder I can usually reduce them sufficiently enough to be happy with the result...
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