Catch in Focus/Focus Trap

I've been using my K-r with a 50mm 'M' lens plus tube for macro recently making a fair bit of use of the catch in focus mode.

I was wondering if this mode can be used to trap an insect ie. leave the camera on a tripod focused on a spot and wait for something to fly in, triggering the shutter. According to lots of articles on a search it can, but I can't get it to work.

As far as I can tell catch in focus should work by pressing the shutter button down fully, then focusing to trigger the shutter. It only works for me if I hold the shutter button down and focus. It won't work if I take my finger off the button. In other words the button isn't depressing fully until the camera achieves focus.

As far as I can tell everything is set up correctly. It's in AF mode, with AF-S and catch in focus set to 2.

Doesn't work properly with any of my manual lenses.

Any help or advice appreciated.

The image has to be out of focus to start with. MF lens. AF on camera.

Then, fully depress the shutter. When the green hexagon indicates focus is achieved, the shutter will release.

Thanks John.

I can do that as long as I keep the button depressed. It won't fully depress until focus is achieved.

What I'm after, that others seem to be able to do, is a way to fully depress the shutter button, remove my finger, then have the camera fire when focus is achieved, so that I can leave the camera on a tripod in a likely position.

To do that you'll need a locking cable release.

Thanks - any way with a remote control?

I don't think so.

I got mine to work with remote control on my K5.

Once CIF is turned on, change "Autofocus when using remote control" to yes. The red light flashes, press the remote and it goes out, the CIF is then enabled without holding the shutter. Just tested with some terrible self portraits.

I will add that you only seem to get 10-12 seconds for something to come into focus....maybe this can be changed?

Thanks. I'll try it tomorrow.

That might be to do with the Meter Operating Time or Auto Power off settings.

John