Tom Reichner wrote in post #18654871.
This makes me curious about something. .
Things you have said in the past about ISO and noise grain have given me the impression that you aren't very picky at all about image quality. .
And you have also said that you never print big - in fact, I think I remember you saying something about only doing tiny little stuff like 8 by 10 inch prints.
So ..... if you are only using the images at very small sizes, and aren't overly picky about image quality, what is it about cropping in to 100-400mm shots that you don't like. .
I mean, you say, "not always the best choice", so what is it that you are displeased with when you crop your 400mm images?.
Tom, am I being overly sensitive, or is this post more than a tad condescending? "aren't very picky about IQ", "never print big", "tiny little stuff like 8 x 10", "only using at very small sizes". I don't believe I've ever read you like that before, but it seems a bit derogatory. May just be me at 3:00 am, but it feels a little harsh.
Nevertheless, you are correct, I care less about ISO noise than lots of other folks on these pages. I have perfectly acceptable ISO 6400 8"x10" prints from my 60D on display. In the 10 or so years I've been using digital, I've made two 11"x17" prints that I can recall. Most times I can shoot my 80D/6D in JPG at ISO 12800/25600 and be quite happy with the results for 4"x6", 5"x7" or web posting.
I do nothing paid; all of my photography is for my own enjoyment, mostly. I share family photos with family, and do the kids' sports/athletics as a way of staying involved (I don't care for sports, but I love my family, and enjoy taking photos). Most of my extended family has photos I've taken on their social media pages.
The point? I've always been a snap-shooter; my photos document my life and the lives of those around me. Nothing more. As such, I care a whole lot more about content than quality. That said, IQ is not irrelevant.
My dis-satisfaction with the 100-400L grows as the subject matter I try to capture gets smaller, and/or more distant. I've used it, with no reservations, at kids' outdoor athletics/sporting events. It turns in stellar (to me) results. We live out in the middle of corn-country USA. Last year my wife put up several bird feeders around the yard. We also have a small stand of trees in the backyard; it attracts critters. The finches and jays of my neighborhood are quite shy. So are the barn cats and local small game. Most of my 100-400 shots of this type need to be cropped to near 100% to get an acceptable framing. Otherwise, I've got a little speck of a barn cat or yellow finch in the middle of a vast sea of endless background. As such, most detail is lost. So far, I have no keepers. I estimate my distance from these subjects at about 50-75', at most. They are skittish, my backyard is wide open and flat; I'm not getting any closer to them. Hence the desire for a bit more focal length.
And I'm a gear slut who can afford to spend $1,000 on new lens just because I want one. As mentioned above, I just ordered the Sigma 150-600 + 1.4x TC. $967, free shipping, no tax. If I hold true to form, 840mm @ f/8 on my 80D should be at least acceptable. That is a HUGE increase in my focal length availability. I believe my tripod will be getting a workout when this thing arrives!