[Rover]

... Unfortunately the bokeh test was not what I've been after that night (which was yesterday).
So much for the 1D4 + L lens autofocus... the 24 is pretty finicky, like the Sigma 14 and Tamron 45 primes I have (whereas most zooms and the Tamron 85 are mostly spot on).
What it should really have been (different framing a little, but same subject; both shots are at f/1.6):

Have you ever had such radical AF/boken fails?

[toni-a]

For me at least it's a classic, usually camera-lens perform very well and nail the focus for each and every shot except the critical one you have been awaiting.... all my cameras will usually do something to ruin the best shot.
Once I was shooting a wedding with 5D 24-105 and speedlight, the shot before, the shot after were perfect the critical shot, the flash was recycling and the camera chose a lengthy shutter speed of 1/2 a second ....
At least you weren't as unlucky as this guy

https://www.youtube.com/watch?v=pGLmdQuxW_s

[Rover]

I've had something to that effect happening too -- not during that shoot, but certainly during all these long years I've been working in this field...
BTW I shot almost 2000 photos during that nocturnal marathon, though well over 2/3 were culled quickly, mostly as technical spoilage (I kept one above for its sheer comedic value, though mostly were just iffy stuff).
Interestingly I only really used two primes to shoot this event (I also had the 100-400 on me but even though the night was white, it was rendered useless pretty quickly).

"The two eyes of twilight". The 45 was left at home because I know how finicky it is for focusing.

[toni-a]

Just a quick tip. don't waste your time deleting from memory card and checking photos on the spot, keep it for later one, the more delete/write cycles, the shorter the memory card and the higher the risk of losing all your shooting .....
In location just shoot, Then once at home download everything, don't delete anything , don't do cut/paste, just download everything then format your card in the camera, I have learnt it the hard way, it's rare it happens, but you imagine the disaster when it does happen.
Once the photos are on a hard disk, feel free to delete the ones you don't want, just resist the urge to delete blurry shots on the shooting location

[Rover]

Yeah, sure. No time for much sorting when I'm on the run. However most photos don't survive the first tentative look on the computer (though I have some shoots from the past month that have gone really unsorted past that initial "select a few for publication quickly, ignore the rest. Which is super irritating, but I have to come back to them someday).

I have dual write set up on the primary camera anyway. The secondary unfortunately doesn't have that luxury.

[wim]

My 24Ls, both I and II, behaved perfectly in diffcult lighting consitions, with beautifully rendered OOF areas, at least IMO. That was both on APS-C as on FF, although I find I do not use the 24L II a lot currently, as I find myself using RF50L and RF85L more than anything else these days. Those two, plus RF 24-105 when I need a zoom, and the Samyang 10 F/3.5 for extreme WA shots .

I tended to use the 24L mostly indoors, in cafés, pubs and restaurants, at night, with awful lighting, and it always performed exceptionally well under those conditions, including AF, even on my 5D and 5D II.

[Rover]

Well, 50 is a long way from a 24... the 24 is a part of my trinity of fast primes (24-45-85) that I use when shooting in the dark. This time it was only 24+85 though and that did get me through the event. There's no point in dragging the 24 out anywhere if there's enough light; the 16-35 is more fitting there, being both more versatile and more predictable.

I don't mean to rail on the 24 - when it's needed there's no substitute - but at times it's comically inaccurate for AF. Sigma 14mm f/2.8 is comparable in being similarly misguided at times, although that one is more "forgivable", well, because it's a Sigma lens from way back in the film era anyway.

[toni-a]

At least for me,  newer  camera bodies have great low light performance, making the need of f1.4 primes for low light situation less frequent unless you absolutely need the shallow DOF, bearing in mind that focus imprecisions are more forgiving at f2.8 than at f1.4. at ISO 16000 unless you need to freeze action with high shutter speed f2.8 is widely enough modren camera bodies almost all offer very usable ISO 16000 or even higher , if you  are shooting RAW, with some new noise reduction software like DXO deep prime you can gain as much as  the equivalent of using 2-3 f stops less of ISO.
Maybe it's time to invest in a a new body, Canon R6 comes to mind first
I attached a photo taken at ISO 16000 EOSRP that isn't the best for noise control but still good enough, then noise reduction was applied via DXO pure RAW, note this is a 100% crop


  c53e3f09-3794-4fc0-b804-8b87e8fe9bb3.jpg (Size: 245.55 KB / Downloads: 10)

[thxbb12]

Woah, I'm impressed by how clean it looks at ISO16000!
It's better than ISO3200 on my Fuji with RawTherapee noise reduction.
I almost never shoot at high ISOs so it doesn't matter to me, but DXO's noise reduction is impressive indeed.

[Rover]

Well, as it is for me ISO 8000 is the absolute highest I'd go, and even then I bear in mind that if I'm shooting that high, the lighting is probably too lousy to get any decent result anyway.
All along the track, I've seen the resident marathon photogs set up ambushes with "proper" lighting because they have to get clear shots of every runner they can (so that those can buy the photos later). I can't imagine doing the same - and moving all across the city loaded with that stuff - though.

In any case, mostly I'm shooting daytime sports anyway; the nocturnal marathon was an exception because it has been moved to its original time frame after years of being "just another" marathon.