Klaus,
Thanks for an excellent test report. I love my 75mm, f/1.8, but when I look through the front of the lens I see a single speck of light. It is tiny and I do not see it in any of my photos. Looking through with the camera upright (as if I were taking a photo of my eyes) it appears a little off center at about 9 o'clock. The brighter the light that shines into the lens the brighter it gets. I thiink it could be a flaw in the coating. I looks almost like a star when bright light is on it.
I am very pleased with the sharpness, contrast etc. of the lens and hate to go through the bother of returning it to B&H and also paying the cost of shipping/insurance. I am even more concerned that I will get a new copy that might not have a 'flaw', but that does not match the image quality of the lens I returned. I am willing to live with a reduction in value of my lens if I trade it in in the future. I do not think that is likely. Do you think I am 'crasy' if I keep this lens rather than excjanging it? Thanks.
Frank
Thanks.
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A lens should be perfect on delivery. However, this is barely achievable it seems.
If a sample is near perfectly centered I would probably accept a defect in coating.
Thanks Klaus. My photos and amateur testing so far indicate that it is well centered. Unless, something shows itself before my 30 days expires I plan to keeep it.
Frank
Check out if bokeh is not affected with this issue.
It should not affect sharp regions in any way.
I would think it would be most visible (if visible at all) when there is a situation that results in flare. Bokeh is typically not impacted but such defects.
Thanks Doroga and anf you2. I will check for both the bokeh and flare.
Can anyone ansewr this for me? The 'flaw' appears just below 9 o'clock near the center of the lens ,when I hold the camera as if I am taking a photo of my eye and look into the front lens. If it doesi mpact the actual image, shoild I see the flaw just below center to the right when I look at an image? Thanks.
Any bokeh issues should be visible in all blur circles.
Flare in frame depends mainly on light source position.
Check whole frame.