1dmkiii + mkIV user question

[Tom_Hughes]

Hi,

I know this has probably been discussed to death but im after some opinons from people who have used both as im buying a 1d mk4 soon.

Yesterday I borrowed a 1d Mk3 for shooting some gymnastics, was using a 70-200mm f2.8ii on this at 3200 iso f2.8 1/320th roughly and AI servo.

This was odviously indoors under artifical lighting which was pretty bad and I found the auto focus to be terrible at times, I couldn't even lock focus on a static gymnast at times with certain colour clothing on but then at times it was perfect but normally at the crucial moment I couldnt get a focus lock which was very frustraiting!! ( It did seem to be worse when i had the spectators behind the subject so it was almost like it couldn't distinguish the subject from the background? )

Now Im wondering how much has the Mk4 been improved over this in these artificaly lit low light conditions? I know this is the harshest conditions to shoot in so would appreciate some feedback from people who have experience with this.

Thanks!

 

[micloi]

If I were you and would spend over 3K on a new camera I would either borrow or rent one first and test it under the conditions I usually shoot in as it will be difficult to base your decision on other people's experiences.

Just my humble opinion.

 

[CT]

Hi,

This was odviously indoors under artifical lighting which was pretty bad and I found the auto focus to be terrible at times, I couldn't even lock focus on a static gymnast at times with certain colour clothing on but then at times it was perfect but normally at the crucial moment I couldnt get a focus lock which was very frustraiting!! ( It did seem to be worse when i had the spectators behind the subject so it was almost like it couldn't distinguish the subject from the background? )

I think you could experience this problem with any camera under those conditions Tom. I assume you'd be using a single AF point which would be the way to go, but you need image detail or contrast within that small AF rectangle for the AF system to have any chance at all of locking focus. If the system doesn't find that detail then it will hunt back and forth and lock on to the first area where it finds detail in the AF rectangle, which seems to have been the audience behind your main subject.

Using a single AF point the face would be the obvious place to focus on, but I appreciate that may well have been difficult given the fact that your subjects were moving, but if you were trying to focus on the plain material of the clothing I'm not surprised you had problems, in fact you could have the same problem even in good outside light at a similar range.

 

[Tom_Hughes]

Thanks for the replys,

I was using the centre AF point, the camera wasn't focusing on the crowd behind it was just having trouble distinguishing the subject from that I feel. ( Thinking about that it shouldn't of made any difference to the focus like as you say its only the small area in the focus point maybe it was just the direction/area of the lights making it harder)

I did also find the same problem when I was taking photos of some young children coming through a play tunnel in the same lighting and I was focusing directly on there faces and there was definatly plenty of contrast to focus on and at times it still would hunt for focus, maybe the mk3 I borrowed was one of the orignal faulty ones or the AF sensitivity could have been set better but I didn't have the time to experiment with CF's.
Also my 40D didn't seem to have any of these problems focusing just the ISO was the problem!