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06-13-2013, 08:11 PM   #16
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Tried it on my P&S today. No go. Made it worse. Oh well. Was gonna scrap it anyway.

06-14-2013, 06:47 AM   #17
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QuoteOriginally posted by ChucK20D Quote
Tried it on my P&S today. No go. Made it worse. Oh well. Was gonna scrap it anyway.
The problem with a P&S lens is, that firstly, it is small anyway and the black spot will take up a considerable greater percentage of the optical surface, than on any standard DSLR lens. Secondly, due to the tiny sensor and short focal length, the depth of field of a P&S lens is so big, that the blck spot might get visible (albeit not sharp) and thus is detrimental to the image quality.

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06-14-2013, 08:12 AM   #18
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Yeah, won't work so well on a wide-angle. Even on my modern Sigma 8-16, if I stop it down too much you'll see a purple spot in the center -- it's own front glass (and coatings) are coming into focus. P&S same thing -- focal point too close to lens (and lens too tiny as noted)...
06-14-2013, 08:41 AM   #19
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Re P&S; As soon as I buy a lens for my DSLR (as I did for my film SLR) I get a UV or skylight filter and put it on right out of the box. I know I may be loosing some IQ by adding another layer of glass to shoot through, but the peace of mind that comes with protecting both the element and the filter ring is worth it....

Can't do that with your typical P&S lens. Even with the built-in automatic lens cap, the lens is still unprotected. And the auto-cap may even be a liability. I had my P&S at the beach and went out one night to see if I could capture starlight. Well, sure enough, it was near pitch dark, and I fell in a hole. Got sand in the cam. And in the lens assy. I cleaned it as well as I could, but the lens cover had grit on the inside and totaled the lens.

Win some, loose some...


Last edited by ChucK20D; 06-14-2013 at 08:41 AM. Reason: typo
06-15-2013, 03:13 AM   #20
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A couple of weeks ago I ended up resorting to an extreme version of the black-paint-in-a-scratch trick. I took a gamble on a very cheap Super Takumar 35mm/2.0 (original version) that was advertised with full honesty as having very heavy cleaning marks -- and the seller wasn't joking. This lens really did look like someone had taken coarse sandpaper to the front element, and it was pretty much unusable at any aperture.

After running out of any other ideas, I took a deep breath and dipped a microfiber cloth into a tin of matte black plastic model paint. I smeared a thin coating of paint all over the front element, gently working it into the thousands of tiny scratches, then immediately wiped the lens clean with another microfiber cloth. The idea being to fill the scratches with paint but leave the lens surface clean. The whole terrifying process only took ten seconds or so, because you sure as heck don't want that paint solvent on the lens any longer than essential. And I stress that this was an absolute last resort with a lens that was completely useless otherwise.

The result? The lens is now perfectly usable at f/2.8 and beyond, and I can just about get away with f/2.0 as long the light conditions are completely flare-free. There is perhaps a third of a stop loss of light transmission because the lens was so badly scratched, but I'm fine with that. Although my hands are shaking right now at the memory of what I did to that irreplacable classic lens. I just wish I'd thought to take some before and after shots.
06-15-2013, 04:35 AM   #21
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Nice! Way to go Dave.
06-16-2013, 11:46 AM   #22
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To followup comments about the toothpaste suggestion - Don't do it on coated lenses. If you have an uncoated lens that you don't really care for, be sure to try it, and post the results
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