Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-24-2011, 08:37 PM   #1
Inactive Account




Join Date: Jun 2011
Location: Gulf Coast
Posts: 45
K5 af.c

Please can someone tell me how to use this for focused results? OK I have studied the manual and says press shutter half way down and focusing takes place, correct? Is it not predictive so that you can use it with the shutter down using motor drive? Not much point having it in focus then when taking an exposure the moving subject has moved out of focus! I am trying to focus on models walking toward the camera with success.

08-24-2011, 08:43 PM   #2
Veteran Member
joe.penn's Avatar

Join Date: Mar 2011
Location: Maryland (Right Outside Washington DC)
Photos: Gallery | Albums
Posts: 2,902
AF.C is continuous - as long as the subject is centered in the VF and the shutter is pressed halfway down, the camera will continue to focus on the subject, even if the subject moves (will re-focus automatically).

If you are looking for predictive, I would recommend switching to manual focus and setting up your camera body for "Catch-In-Focus". But then again, if you are shooting in continuous focus mode, just snapping series of pictures as the model is walking towards you should work fine...







---
08-24-2011, 08:54 PM   #3
hcc
Pentaxian
hcc's Avatar

Join Date: Nov 2009
Location: Brisbane, Australia
Photos: Gallery | Albums
Posts: 4,002
I have done a few shots of children advancing towards me, walking, running and even cycling. Typically (but not always) outdoor. This experience is somehow similar to yours although the moving object might be different.

I obtained (what I deem) my best shots using MF lenses (or AF lenses set in MF) for which:

- I pre-determined the focus distance (on the focus ring) at a distance between myself and the start of the children run/walk,

- I set the shutter speed to at least 1/20s (or 1/60s) for walking (or cycling) kids running straight at me; I use shutter priority (P mode+ force manually the shutter speed)

- I use Hi continuous shooting.

It is possible to use Catch in Focus (CIF) with walking children but it does not work with running or cyclings kids. (Trust me.)

Note that, for automative objects like cars and bykes, the above will work although I would use a faster shutter speed (1/1,000 s or faster).

I hope that the comments will help....

Last edited by hcc; 08-24-2011 at 10:06 PM.
08-24-2011, 11:22 PM   #4
Inactive Account




Join Date: Aug 2008
Location: Michigan, USA
Photos: Gallery | Albums
Posts: 7,484
QuoteOriginally posted by hcc Quote
- I use Hi continuous shooting.

It is possible to use Catch in Focus (CIF) with walking children but it does not work with running or cyclings kids. (Trust me.)

Note that, for automative objects like cars and bykes, the above will work although I would use a faster shutter speed (1/1,000 s or faster).

I hope that the comments will help....
I don't know about running kids but Low continuous works quite nicely with CIF. I can point the camera about at different areas while turning the focus ring and get every shot. None of it equals a fast moving subject however unless you count, The Hound. For him, my reaction time is usually a little slow even though I know exactly where he's going. I've never had a great deal of luck with AF-C. Supposedly it's suppose to work with a Focus Priority if you set it that way but it will still snap photos regardless of actual focus. Instead, I find better results using AF-S and just continually repressing the AF button or the shutter release half press. That's probably just because I'm use to doing it that way though.



08-25-2011, 02:34 AM   #5
Pentaxian




Join Date: Jul 2009
Location: London
Posts: 1,116
I find af.c works best for subjects moving across the frame, up to c45 degrees.

Afraid the af is just too slow for anything moving (fast) at 90 degrees towards or away from the camera.

I would have thought that subjects walking towards the camera would be ok though.
08-25-2011, 06:17 AM   #6
Banned




Join Date: Jan 2009
Photos: Gallery
Posts: 9,675
Well, don't know about the models speed, but that should be possible.

You don't press half on the shutterbutton, but full press it and it takes pictures. Some in focus and some not, since it changes focus when it sees that the subject is out of focus. For this Lo-speed continous is a good choice.
08-26-2011, 06:50 AM   #7
Site Supporter
Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 6,699
I should probably try this in continuous not AF.C but if you snap quickly it works pretty well.
Kiowa's not the quickest dog, but once he gets his mass up to speed he's pretty fast:


08-26-2011, 07:27 AM   #8
Inactive Account




Join Date: Aug 2008
Location: Michigan, USA
Photos: Gallery | Albums
Posts: 7,484
With a little bit of sharpening help (AF-S)...



08-26-2011, 08:36 AM   #9
Junior Member




Join Date: Nov 2010
Location: Nederland
Photos: Gallery | Albums
Posts: 32
I did a lot of afc testing with my kr and k5, the results are on my homepage under the `kr k5`section.
Http://www.dijkx.com
08-26-2011, 09:20 AM   #10
Veteran Member
philbaum's Avatar

Join Date: Oct 2007
Location: Port Townsend, Washington State, USA
Posts: 3,659
I do a lot of live theatre shooting during rehearsals. I always use a large DOF to put less pressure on focusing, say f5.6 to f8. With human motion, the slower the shutter speed, the more fuzzier the arms and legs and the fewer keepers. 1/160 is my current favorite speed. I use the AF button and focus on areas of the stage and don't use the half-button focus. I get a high acceptance rate using these techniques.

For gray and killer whales, i've used 1/1500s and 1/2000s.
08-27-2011, 08:07 AM   #11
Inactive Account




Join Date: Jun 2011
Location: Gulf Coast
Posts: 45
Original Poster
Yes, I have found that after some try outs I use the AF button and leave my thumb pressed on it until I need to refocus. The problem was,I think,the FA31mm trying to refocus after an exposure was made although the subject had not moved in distance the same focus spot may have shifted a little. Although it allowed me to take a slightly out of focus exposure anyway when it was in that refocus mood! I do not have that option in custom settings checked so it should not have allowed exposure in theory. So AF button it is. I have NOT had any soft exposures since as of yet and has made using the camera with no worries so I can enjoy what I see in the viewfinder rather than waiting for exposure conformation signals!!!
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, focus, k-5, k-5 ii, k-5 iis, k5, pentax k-5, shutter


All times are GMT -7. The time now is 08:03 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top