james_r2 Posted June 14, 2014 Share Posted June 14, 2014 <p>A recently acquired lens has some sort of debris adhering to aperture blades: Moves when aperture is adjusted, and extends over edge into fov between f2 and f4. (see pix) Haven't got roll back from lab, so influence on IQ is unknown.<br /> Wondering<br /> 1: what it is & how it got there:<br /> sloppy tech?<br /> stray bit of metal or plastic that found its way in, or evidence of damage to the lens?<br /> 2: potential for damaging or interfering with glass or mechanics</p><p>Thoughts?<br /> <br /> </p><p> </p> Link to comment Share on other sites More sharing options...
james_r2 Posted June 14, 2014 Author Share Posted June 14, 2014 <p><img src="/photo/17789916" alt="" /></p><div></div> Link to comment Share on other sites More sharing options...
james_r2 Posted June 14, 2014 Author Share Posted June 14, 2014 <p><img src="/photo/17789914" alt="" /></p><div></div> Link to comment Share on other sites More sharing options...
koray_p Posted June 14, 2014 Share Posted June 14, 2014 James, there are no plastic parts in these lenses, it certainly looks like a metal shaving. The coating on the glass elements are quite soft so if I were you I stop operating the aperture and would definitely get it checked. I disassembled a DR few years ago and I remember the distance between the aperture blades and the glass was very little. K. Link to comment Share on other sites More sharing options...
knut_schwinzer Posted June 14, 2014 Share Posted June 14, 2014 <p>Could be a flake of paint?! Try slapping it gently into your palm in off center direction of the debris, anyways, if it does or doesn't disappear to the extraradio of the lens, CLA would be a good idea for the enthusiast. OTOH, if it sticks there, it shouldn't affect your pics at all, only resale value. Many good pics have been taken with "dirty" lenses, inside and/or outside. Did you ever shine a flashlight through your fav lens?! Be in for a nasty surprise! This is mostly done by salesmen who want to have a bargain on your trade-in, it hardly ever counts in real world photography. After all, a lens like yours may have been moved in and out literally +two miles+ or more in the last 60 years, so don't worry, it will outlive you with outstanding PQ as-is. If you will review the first pics, keep in mind that it isn't very flare resistant per se even without your private UFO.<br> Best, Knut</p> Link to comment Share on other sites More sharing options...
john_shriver Posted June 15, 2014 Share Posted June 15, 2014 <p>Almost certainly a flake of paint that came off the edge blackening on one of the elements. They paint the edges of elements that aren't against the mount black to prevent reflections.</p> Link to comment Share on other sites More sharing options...
james_r2 Posted June 21, 2014 Author Share Posted June 21, 2014 <p>Knut and John - Paint chip confirmed by tech.<br> Tech also confirmed permanent haze on one element that was also not mentioned by seller -<br />guess the KEH people need glasses.</p> Link to comment Share on other sites More sharing options...
knut_schwinzer Posted June 22, 2014 Share Posted June 22, 2014 <p>Welcome, James!</p> Link to comment Share on other sites More sharing options...
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