7D AI Servo Tracking speed adjustment

[Papathanassi]

Re: 7D AI Servo Tracking speed adjustment

Try and get to grips with the back focus button setting Dave for Birds In Flight! I think this what your asking?

Papa.

[colin C]

Re: 7D AI Servo Tracking speed adjustment

Hi Dave

I completely agree with Stan regarding back button focus.

Once you get used to it and it becomes second nature, not only is it better for wildlife shots, but if the system gets momentarily confused between the background and the subject, "pumping" the rear button re-acquires the subject, without the system having to hunt for it. Much quicker re-focussing, resulting in less lost shots.

Colin

[briansquibb]

Re: 7D AI Servo Tracking speed adjustment

I find the half press works best for me along with the af lock button.

[bexman]

Re: 7D AI Servo Tracking speed adjustment

Another vote for back button focus from me! I've had a lot more 'keepers' since using BBF.

I think its horses for courses but for me and my dodgy shutter finger it works well

[DaveCurley]

Re: 7D AI Servo Tracking speed adjustment

Right lads,
Back focus button ? I have found it but what is the technique ? I will play with it this weekend weather permitting

[colin C]

Re: 7D AI Servo Tracking speed adjustment

Hi Dave

Its purpose is to separate the exposure, shutter and focus functions into two separate ones, rather than do all three on the front shutter button.

Use the rear AF button to lock on, focus and track your subject, which is brilliant for fast moving subjects. I also use it to advantage for still subjects, especially when I want to recompose. Back button focus on the still subject, release the back button, recompose and take the shot. If you lose focus on a moving subject for whatever reason, just release the back button and re-acquire the tracking. In really difficult lighting, you can pump the rear button to keep re-acquiring focus.

Some people take to it immediately, whilst others (me) took ages until it became second nature, but well worth the effort.

Check you camera manual how to set the Custom functions for it to work and perservere, it's well worth the effort.

Colin

[DaveCurley]

Re: 7D AI Servo Tracking speed adjustment

Hi Colin,

Most grateful for your advice, tried it and it appears to work, does using the AF on button stop the shutter release control of AF ?

Dave

[Papathanassi]

Re: 7D AI Servo Tracking speed adjustment

Correct.

Papa

[DaveCurley]

Re: 7D AI Servo Tracking speed adjustment

cheers,

my turn for the drinks round

[Trevoreast]

Re: 7D AI Servo Tracking speed adjustment

Certainly when I first saw it, I assumed it controled the speed of the AF mechanism. This is not the case. What it actually controls is the time which has to elapse after the AF looses lock on before it looks for something else to lock on to

Yes, I think you're spot one there Oggie.

I also use it to advantage for still subjects, especially when I want to recompose. Back button focus on the still subject, release the back button, recompose and take the shot.

Colin, now we're talking about the backbutton focussing - I've been using that for a year or two as my 40D has it, and the 30D has it, even though it hasn't got a dedicated button.
There is more on the net about it's application in stuff like birds in flight and sports.
It is very useful for static subjects, low light landscapes, and it works well with a lens in MF.
I'm sure everyone knew that.

I shoot almost exclusivley in manual (manual with metering) I was surprised by some of the neat tricks you can do with the 7D and BBF with the camera in AV mode.

Trev

[DaveCurley]

Re: 7D AI Servo Tracking speed adjustment

if you want tricks with av, then have a day with Graig Jones, a great wildlife photographer from Stoke on trent, he can teach real tricks which I am just starting to play with. www.craigjonesphotography.co.uk

[markgsmith]

Re: 7D AI Servo Tracking speed adjustment

If you have something that's tricky to follow then you want as slow as possible. Sounds counter initiative but that's what you need to do. If you have something that's easy to follow then speed it up and it will lock quicker.

For example:

When tracking a bird in flight against a busy background you want the focusing as slow as possible. You pick the bird up, lock on and then the last thing you want is the AF jumping off the bird as you wield your 500+1.4 in it's direction so the slow setting means it's slower at looking for a new focusing point.

When photographing a 100m sprinter head on using a monopod then they'll always be in the centre of the frame. Set it to Main Point and speed up the AF and it's keep hold of the runner at any speed as it will constantly be looking for the nearest point ie the runner.

[jonesgj]

Re: 7D AI Servo Tracking speed adjustment

Yip, I agree with markgsmith - I have mine set to slow and it seems to work quite well.

Graydon