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bper Jun 5, 2007 1:45 PM

Last weekend I was taking some pictures of wildflowers and my DL starting to not fire when the shutter was depressed.I was right in the middle of composing a flower picture and didn't take the time to figure out what was wrong other then to look at my battery indicator and make sure my dial was set to M. I was using an M50 Macro, so manual focus. I finally got it to work by pressing the shutter down and focusing in and out.

It turned out to be that I had bumped the focus switch into AF mode and it will not fire unless the focus light comes on. I amnow feeling this might not be a bad way to focus, especially if you are in an awkward position or the wind is moving the subject or you get the shakes. Just push down the shutter and turn the focus ringuntil it fires.

It seems like I get my share of out of focus close ups, so this might be worth a try. I would think it would work good withAF lenses if you changed the focus over to the OK button in the menu.The picture I took using this techniqueof Bristly Fiddleneckis below- Bruce

robar Jun 5, 2007 1:54 PM

this technique has been around awhile. it's called ''focus trap''.


robar Jun 5, 2007 1:54 PM

this technique has been around awhile. it's called ''focus trap''.


thepusher Jun 5, 2007 1:55 PM

Good Capture!!

Excellent Tip!!:|:|


bper Jun 5, 2007 2:33 PM

Hi Roy - I knew about the technique. I have seen it used to capture hummingbirds in flight. I thought maybe some of the new forum people would like to hear how it is done. I would be interested in hearing and other ways people have foundof using this type oftechnique incapturing images. My eyes are getting harder and harder to see a clear focus- Bruce

Fl_Gulfer Jun 5, 2007 3:33 PM

Could someone explain this in more detail and does it work on all DSRL Pentax?

Lyrics51 Jun 5, 2007 4:39 PM

I have three auto focus lenses and they all don't want to move, or at least not move well, manually when I am in the autofocus mode. I tried it in the OK mode as you suggested and the camera fires in or out of focus. I have no manual lenses to test.


Corpsy Jun 5, 2007 5:11 PM

Fl_Gulfer wrote:

Could someone explain this in more detail and does it work on all DSRL Pentax?
I described this technique in a thread I posted 3 days ago:;forum_id=80

mtngal Jun 5, 2007 9:20 PM

It works on all of the Pentax dSLRs - it can be very useful, but I find that I tend to move the camera too much when turning the focusing ring. I think it works best with faster shutter speeds or perhaps a tripod. It would probably work better if I had larger hands.

bper Jun 5, 2007 9:44 PM

Sorry I was away from this discussion for awhile. I think to clarify things, as far as I know it works well only with manual focus lenses. I could be wrong and maybe someone can explain how to do it with an AF lens -hope so. I seldom use AF lenses anymore. I just like that old glass.

I have not used it a lot yet, but I think it could be very useful for wildflowers, especially the long stems ones on a windy day. Just find a happy medium, press the shutter and wait for the flower to blow in.The problem is you cannot have anything else near the focus point or it will fire off. For instance if you wanted to catch a flighty insect on a flower, I don't think it would work.

There are two versions you can do. One is the one above where you let the flower blow in to the focus point. The other is to start off focus and turn in the focus until the focus light comes on andsensor fires the camera.Either way amounts to the same thing. Your letting the camera decide the optimum focus point. This can be good or bad depending on many other factors. Anyway, it's a technique that is worth a try under certain conditions and one to have in your bag of tricks. So next time you have that M lens on, flip the switch on the side to AF, press down the shutterand give it a try- Bruce

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