Nah, if I miss focus so much that it was visible at 1000px it would be deleted before I even got home.
All of my shots are processed for printing large. For posting here, I just take those shots and run the same batch. It kills a lot of info and depending on the shot introduces noise, aliasing (especially since they were already sharpened at full size) and banding. Basically a bicubic resize to 1000px, slight global sharpening to combat it, and then export as medium quality jpeg. Look at the file sizes.
Works better on some than others and gets bad when ISO is over 800 (such as OP) and the subject isn't filling the frame, especially when it comes to feathers. I don't care much as 4chan isn't my priority, but do have some standards; quite a few shots that I really like just looked so shitty after resizing I never bothered posting them... maybe someday I'll get around to digging up the original RAWs and doing them manually.
Here's one of the borderline shots I never posted because it looks blown. I like things to look how they appeared in reality, and the truth is some birds tend to glow a bit in certain light. For those occasions I'll shoot wide open and expose just enough to keep the highlights in check to capture it. Resizing can push those shots over that fine line and make them appear blown because the gradient is gone. Basically, few people understand and it leads to "muh highlights". I did post one that was legitimately blown though, out of necessity:https://archive.nyafuu.org/p/thread/3245840/#3253054
TL;DR: Ambush made a blog post and posted a new shot, holy fuck. He never does that. Anyway, back to hating on him as he shitposts in trash threads you shouldn't be posting in to begin with.