Servo Mode ??

pearce_jj

pearce_jj

Messages
1,854
Edit My Images
Yes
Hi

I'm wondering if someone can offer me some assistance with servo mode as I just can't seem to get results with it.

My subjects are basically my kids. For example running down a steep hill. 5D, 70-200F4L, single point AF, servo and continuous. Fire off a few frames, every single one is back focused. Camera has been calibrated and locked on to a stationary subject it's fine.

But then I see photos on here like on this bird thread, http://www.talkphotography.co.uk/forums/showthread.php?t=128081, which surely must have used it - how does it actually work!?!

Thanks for any help.
 
Hi, thanks for the reply. Here are four consecutive shots hopefully with exif intact (exports from PSE):

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8806.jpg

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8807.jpg

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8808.jpg

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8809.jpg
 
Not really answering your question here but.....the second frame looks front focussed to me.

Bob
 
Go into custom functions and make sure 17 is set to 1:Expanded as this activates 6 hidden AF points around the centre point when in AI Servo Mode and is a godsend :)
 
Isn't the AF rather average on the 5D anyway? Apart from that, the drive is slow and the predictive focus has to do a lot of guessing between frames.

If it was a 1D I would be worried.
 
Thanks all. Will check the hidden points and try again with centre spot.

I doubt that the wife nor or Halifax Card Services would be that impressed with a 1D upgrade!

Also re AF, the 5D only enables its 'high precision' mode with 2.8 glass IIRC, I just bought the 70..200F4L favouring the IS over the 2.8 because of my shaky hands - maybe the wrong decision thinking about it!
 
HoppyUK said:
Isn't the AF rather average on the 5D anyway? Apart from that, the drive is slow and the predictive focus has to do a lot of guessing between frames.

If it was a 1D I would be worried.
Click to expand...

I think you might be confusing the slower frame rate with slow AF, Both the lock speed and AF speed on the 5D are very good ( with the AF area expanded) but it all depends on the focusing speed of the lens more than camera. :)
 
CScottMcQueen said:
I think you might be confusing the slower frame rate with slow AF, Both the lock speed and AF speed on the 5D are very good ( with the AF area expanded) but it all depends on the focusing speed of the lens more than camera. :)
Click to expand...

I would have thought any USM lens could keep up with the 5D's very modest 3fps once it has locked on?

I'm guessing here, but isn't the tricky part that the camera has to estimate where the subject will be for the next frame? The more depth of field (or rather depth of focus with AF) that it has to work with the less precise the calculation data will be, and if there's a big gap between frames the room for error goes up. Predictive AF also assumes the subject moves at a contast speed, so maybe the young lad's faltering run will not not help.

Perhaps a combination of factors? But I have to admit I'm no expert on this. I tried it on my 40D and it was pretty hopeless - in line with other people's experience with all the sub-pro cameras - so I've not used it since. I don't shoot a lot of action, but if I did the superb AF on the 1D cameras would be a priority. For now, I use my own old fashion 'predictive focus' - pre-focus on the spot I want and then try to fire off a single frame at a time. That's not very successful either!
 
Evening all

More success this evening - my option 17 was already enabled so I tried some more with the centre spot. After getting a load of motion blur at the same time yesterday I also upped the ISO, a bit too much, hence the noise, but it seemed to work properly with these,

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8972_edited-1.jpg

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8973_edited-1.jpg

http://sittingbourneSPAMerver.com/downloads/Photos/TP_Shared/servo/img_8974_edited-1.jpg


Now I'm wondering whether the 2.8L would have been a better bet, to get those backgrounds more OOF....
 
You must log in or register to reply here.
Back
Top