I am finding it hard to get a really sharp photo through the two layers of thermal glass on my deck door when shooting birds at my artificial thicket back deck feeder station. The photos look sharp at reasonable viewing sizes, but when pixel peeping, you can see that they are not quite there. This one, however, passes the pixel peeping test. Maybe I found a section of particularly flat window glass   I am waiting for warmer weather when I can shoot through the open door, or even go out and sit with my laptop in the corner of the deck furthest from the feeders and pretend to be part of the scenery.

Canon SX50HS. Program with iContrast and Auto Shadow Control. –1/3 EV exposure compensation. (And even that only just held detail in the whites.) 1200mm equivalent field of view. f6.5 @ 1/1000 @ ISO 500. Processed in Lightroom for intensity, clarity, and sharpness.