"catch in focus"

No, not with your lenses (Pentax DA* 16-50mm; Sigma 70-300mm APO DG), or any AF lens, unless Liam's idea works!

Maybe, but the much simpler answer is to use an A series lens. They are cheap enough on eBay.

I must be dense, but I can not make this work. Here's what I'm trying:

•The K7 with both the Asahi 50mm f1.4 and the Rokinon 85mm f1.4.

•I'm trying both with and without tinfoil over the contacts

•I have the camera set center point, single focus, and catch-in activated in the camera's C menu.

But I press the shutter and the photo takes, whether I'm in focus or not.

What setting am I missing? I would love to make these two old lenses useful to me on the job. As it is now, I can never use them for anything practical (I shoot mostly moving people).

Do you have the camera set to AF? If not, do so and it should work.

Yes, I have it on AFS. I can make it work with the K5 we have at work when I put our (broken) Pentax 16-50 on it. The AF stopped working, but with catch-in, it works again.

So I've done it before, but I can't do it now.

Perhaps you are starting with the lens too much in focus? Don't forget that if the green hexagon is lit and anything is in focus it will fire the shutter.

Thanks for the advice so far, but I have to ask. Green hexagon? I've never seen that. But I am using an aftermarket focus screen, if that has anything to do with it.

And I'm not starting in focus at all. I can be 10 feet out of focus on a subject 3 feet away from me and it fires anyway.

Please don't tell me something's broken!

EDIT: Do Pentax cameras have a toggle for Frames-per-second-priority versus focus-priority? I know some cameras do, but I can't find that in the options here.

Looking through the viewfinder, there is a green hexagon that lights steadily when a lens is in focus, be it an AF or MF lens.

The essentials: You need a manual focus lens and the camera body set to AF. The shutter will only release when the lens is in focus, as indicated by the green hexagon.

Ah. I see the hexagon now when I attach my 50-135. I've never looked for that because I only look at the red focus-confirmation square when I shoot.

Anyway, if I mount a manual lens and try it, the green hexagon never lights up.

Oi! What's going on here.

This is interesting for me as I love to take Whitewater Canoe pictures and as it seems it will work with the K5.

Will I need a Pentax A lens or can I take my manual 500mm M42 with the PK adapter?
Also, can I use a manual TC?

I never heard about this technique (but then again I am only shooting with a Digital SLR for a few month now, till then the best I had was an F2AS).
So far I love my K5 and I really can see me getting all the stops out with it once the body has been replaced by SRS because of the Glass fault on the sensor.

I used the interval timer yesterday morning and got some fab shots but sadly you can see the fault in the picture (see my other thread for this, also it is not as clear as on my computer as flickr will let me only upload to 1/4th of the original size for whatever reason.

But this trap one is a good one which I have to practice for the spring when the Whitewater Canoe season starts again in earnest.

I don't know, but the red square is not focus confirmation. It just shows you where the camera is focusing and when it's finished. It's the green hexagon that confirms focus. And our eyes of course...

Because you don't have a pro (paid for) account.

Once you start paying you get all the display options.

They did not used to be that tight Oh well, it goes on my wish list for Christmas
Thanks for that as I could not figure this one out. Even in FAQ's.

Anyway, anyone know if the "catch in focus" will work with Pentax M lenses (or M42 lenses with adapter)?

Ah ha! I figured out why my catch-in wasn't working.

I like to use only my thumb AF button for focus, and so I normally disable the regular shutter from activating focus. And apparently for catch-in to work, I must be using the shutter button for focus.

Well I wish it weren't that way, but ok. At least I've got it figured out.

Thanks for the help!

K-5 does but no previous Pentax DSLR has (afaik)

M42 doesn't short the contacts...

Tin foil.