How can I improve the sharpness of my Sigma 50mm 1.4 DG HSM lens?
9833
Why are my photos not crisp?
89982
How can I fix an out-of-focus blurred photo in Photoshop?
12994
Is it physically possible to build a long zoom (17-300 mm for example) at an aperture value of around 1.4 or 1.2?
100631
Is an EF 50mm f/1.4 the same as 50mm with an EF-S lens on a Canon 550D?
3867
is it normal to get significant lens flare with a 50mm f/1.8 prime lens?
49930
How do I prevent condensation on a lens when outdoors?
29080
How do extension tubes affect focusing distance?
71343
Is there a noticeable difference between 1.8 and 1.4 prime lenses?
52215
How do I create a wide-angle / fisheye lens with HLSL?
34665
What image-quality characteristics make a lens good or bad?
109652
What is the limiting factor in lens construction when it comes to f-stop values?
148895
Why can't I turn the focus ring on my Vivitar 100-300mm far enough to get infinity focus?
151884
How do I set focus range?
62822
How can lens cause consistent front or back focus?
14182
How to ensure sharp focus when shooting with an open aperture?
144558
Lens with small scratches on the front element - how do they affect IQ?
15467
Subsurf on a crown. How can I smooth some edges and keep others sharp?