Canon 85mm f/1.2 for low light sport?

I've been considering adding a prime lens to my zooms (70-200 F/2.8 IS & 24-70mm F/2.8 both MK I) because I'm increasingly frustrated with the problem of needing full ISO (3200 on 1D3) and not quite fast enough shutter speed to capture sport - namely karate tournament where I cannot use flash, and need a lot of to post-process to get anything like reasonable exposure.

I'm thankfully allowed quite close to the competitors, and have been through a lot of shots to see that usual focal length is around 80mm so I'm considering adding a second-hand 85mm F/1.2 L

Given my budget won't allow upgrading the camera anytime soon, I was thinking an 85mm would do the job, but wonder if the focus speed is similar to (or better) than the zooms I already have.

Any thoughts? does anyone out there use an 85mm for quite fast action sports in low light care to comment?

People use the 85 f1.8 for sports. The f1.2 is not known for focusing fast enough for sports.

85 1.8 or 5D3 would be my choice.

5D3 you should be able to use ISO6400 and halve your shutter speed for same exposure, half the motion blur (just plain facts) and noise without researching I'd assume equal or better.

I've used the 85 1.8, 100 2, 135L, and 200 2.8L II for indoor sports. All can keep up with basketball and hockey. With the exception of the 200, all will help keep your ISO down.

My 1D mk3 drives my 50L (similar bulk) well enough for ring sports, so i would think so.

Bassat wrote in post #18576370
I've used the 85 1.8, 100 2, 135L, and 200 2.8L II for indoor sports. All can keep up with basketball and hockey. With the exception of the 200, all will help keep your ISO down.

135 gets my vote too.

bildeb0rg wrote in post #18576379
My 1D mk3 drives my 50L (similar bulk) well enough for ring sports, so i would think so.

I am sure the 50L is a bit different. The 85L just isn't agile enough. If focus just various a bit from shot to shot, it may keep up, but not consistently. If action shifts far enough away or closer, the focus take what seems to be an eternity. I love the 85L, and tried it once during a soccer match. That was the last time I used it for sports. Portraits, though, oh yes! It is one of my all time favorite lenses, it is special.

If I were you I would really consider a 1D MkIV instead of the 85mm. Used, the body might be a couple of hundred less than the lens. I had one and was fine with using it at up to 10,000 ISO. As long as you don't underexpose it worked well and it was really built for shooting sports.

bpalermini wrote in post #18576616
If I were you I would really consider a 1D MkIV instead of the 85mm. Used, the body might be a couple of hundred less...

there have been several 1DIV on sale here for under a grand or "right at" a grand...

almost popped for one myself but i shoot nighttime football for my daughter's highschool and they have HORRIBLE lighting and routinely shoot 12,800 ISO and i was afraid it would be too noisy. its REALLY dark on their field...

that said, i have no experience with the 85 of any speed, but i have heard the 1.2 is a slow focus beast. the 1.8 could very well be your ticket with only 1/3d less stop (speed)...

joeseph.. the 85 1.2 is a beautiful portrait lens, but it would never stand up to the speed of sport.
It's very slow. I don't know about the Mark 2, but that lens was just not built for sport.
Though I'm sure someone will chime it to say they use it

The 1.8 might work.. that I don't know.

I'm sorry I don't have a suggestion for you, thought the 135 /2 is fast a produces beautiful images.

Actually, I thought that the 1D4 did very well at high ISO.

Thanks for the suggestions all - I hadn't considered a 1D4 would be that much of a step up, looks like it would be worth looking into. Nor did I realize the 85mm f/1.2L is that slow!
Had a 50mm f/1.2L a number of years back but sold it on as I didn't use that focal length very much.

I did another karate event today where the hall had quite a lot of natural lighting but I was having to shoot almost directly into it most of the time and because it was sunny I have a lot of shots where the reflection off the floor is brighter than the light on the competitors.
At least I was shooting manual and the exposure of the subject is reasonable & I was able to keep shutterspeed above 1/400

The 85/1.2II should work. I've shot fast action indoor sports and never found the focus speed to be an issue if your subjects are isolated within a small boundary (e.x. kendo should have the same or close boundary dimensions as seen below). I've been shooting kendo for years now so I can kinda anticipate where players would go, so I would sometimes pre-focus or move to an angle where they are within the same focal plane.

IMAGE LINK: https://flic.kr/p/WXjX​rZ

IMAGE LINK: https://flic.kr/p/WmU4​ys

IMAGE LINK: https://flic.kr/p/WTJ3​1Y

The second version 85L was supposed to be about 50% faster focusing than the original 85L, but it still doesn't focus snappy fast. I use my 85L ver II for street photography and it works out fine. I wouldn't consider using it for sports work however.

panicatnabisco wrote in post #18580670
The 85/1.2II should work. I've shot fast action indoor sports and never found the focus speed to be an issue if your subjects are isolated within a small boundary (e.x. kendo should have the same or close boundary dimensions as seen below). I've been shooting kendo for years now so I can kinda anticipate where players would go, so I would sometimes pre-focus or move to an angle where they are within the same focal plane.

IMAGE LINK: https://flic.kr/p/WXjX​rZ 1DX_0258 by Albert Facultad, on Flickr

IMAGE LINK: https://flic.kr/p/WmU4​ys 1DX_1555 by Albert Facultad, on Flickr

IMAGE LINK: https://flic.kr/p/WTJ3​1Y 1DX_3724 by Albert Facultad, on Flickr

thanks for posting these! this really helps a lot and are fairly similar to the scenario I'm trying to get better with.
I often find the bouts in karate are a lot of time with the competitors just circling each other, then a mad flurry of flailing arms & legs so it's almost a case of guessing when someone will strike.