[LeoTaylor]

I hate to repeat a question that has been asked a few times before, but I'm really stuck.

Objective:

Use my new D FA 50 F2.8 Macro (Solstice Present from my wonderful wife) to take photos less than 1 foot away from a squirrel feeder. Aim tripod where the squirrel will be, using a holly bush as a background.

Problem: The Forum messages conflict on setup. One thread had detailed instructions, the next post said most of that was wrong and had different instructions. Perhaps the confusion is the K10D, istD, and K100D procedures are different?

What I tried:

Inside the warm house, using my hand in front of the lens as a subject I:

Covered the data pin on the lens with scotch tape, indeed K110D stopped autofocusing the lens. Acted like a manual lens.
Tried AF-S and AF-C
Tried MF and AF.
Locked the shutter down with Pentax remote cable as well as using my finger.

Results:

With MF the shutter would activate with the button regardless of whether my hand was in focus. With AF the shutter button was locked out. No sign of Trap Focus as I moved my hand though focus range. No focus indicator in the viewfinder as my hand moved.

Any suggestions as to what am I doing wrong? Is Trap Focus only for K10ds?

[Canada_Rockies]

Unfortunately, trap focus only works on manual focus lenses. It works on any Pentax AF camera other than the ME-F.

I think you have the right idea about the pins, but have the incorrect pin. I think maybe the pin you need to cover is the one that identifies the lens type. That would inform the camera that you are using a K or M lens. You would then have to enable the f/stop ring in the menus, and use the f/stop on the lens mount, because the camera won't be able to set the f/stop with the edial.

I have no idea which pin that would be, but I am getting rather interested, because my big complaint is that I cannot trap focus with my DA lenses!

[LeoTaylor]

...
I think you have the right idea about the pins, but have the incorrect pin.

Hi, thank you for the prompt reply. I got the pin location from an external link found on another thread on this forum. It even included a diagram, the first pin next to the screw head.

As I mentioned, the scotch tape covered pin made the new macro focus like a manual lens so I believe I had the right pin. We are having our first warm sunny day in awhile, so I will try again today. I'll experiment with my K1000 50mm manual, if I get trap focus working I'll try the macro again. I'll keep watching this thread to see if someone posts instructions for a K100D.

The Squirrels are awaiting their peanuts and I'm dieing to use my new lens!

[LeoTaylor]

At long last I achieved Trap Focus with my K100D and new Macro lens. I experimented
with a manual 50mm and found several options that were not mentioned in the previous
threads, or at least not all in one place. The basic idea worked, though the short Depth
of Focus of the Macro resulted in only part of the squirrel being in focus. I'm caught
in a squeeze between fast shutter to stop motion and narrow aperture to increase DOF.
But I'm glad I got some results.

In the next post I will list the setup I used. If anyone can suggest corrections please
do. Then we will have a reference for those who follow.

[LeoTaylor]

Trap Focus with K100D, where the camera shoots continuously when an object is in focus.

I achieved Trap Focus with both manual and autofocus lenses using the following steps. Some may be unnecessary, but this setup worked for me.

If you use a Manual Lens skip this step. To prevent autofocus lenses from focusing block the first contact next to the screw head using tape. You will risk gumming up the contact... For more details and a link to a diagram of the contacts see the Pentax Forums thread called "Trap Focus."

Mode Dial > M
Record Menu > AF Mode > AF-S
Record Menu > Swtch dst msr pt > Center Spot (may be greyed out)
Setup Menu > Auto Power Off > OFF
Custom Menu > Using Aperture Ring > Permitted
Fn Button Menu > Drive Mode > Continuous
Front of camera slide switch > AF
Rear of camera slide switch > SR Off
I used external power since the camera was left on for hours.

Focus camera at desired distance.
Aim camera slightly away from any background objects at the focus distance.
Lock shutter with remote shutter cable or shorting plug.
Test by passing your hand slowly through focus point.

When complete, don't forget to set the above options back to your favorite settings, especially Auto Power Off.

[barondla]

Thanks for the setup. Sounds like you are on the way. To get more dof why not use a flash?
thanks
barondla

[LeoTaylor]

Thanks for the setup. Sounds like you are on the way. To get more dof why not use a flash?
thanks
barondla

I suppose that might work, but the squirrel might not come back after being flashed. Twice the sound of the trap shutter caused the guy (gal?) to look straight in the lens for the next shot. This was more a test of Trap Focus than an effort to get a good picture. As you can see by the awful attached image at 1/60 sec only the ears were in focus when the Trap snapped.

I'll try again sometime with a manual lens a bit further away so the focus won't be so critical. I'll try to get better light on the subject so I can decrease the aperture. I took some indoor flashless flower photos at f11, 1/6 second and they came out well, but unlike an animal, flowers stay still.

Sure enough, this morning I was having trouble with my new macro. I noticed the camera could not display the aperture, just F--. I even reset the camera in case it was a setting I made for Trap then forgot. Eventually I remembered the tape I put over the lens contact yesterday!

Attached Images

 

[LeoTaylor]

I'm getting the hang of this Trap Focus.

I started with the K100D reset to defaults and followed my Trap Focus instructions listed above. I put on a Sigma Manual Zoom set around 210mm f6. Trap started firing once I had enough light for my indoor hand test.

I set up outside with a "bird feeder" just to the left of the camera focus point. I figured I'd only get exposures when a bird or squirrel was centered, so I went in the house for 90 minutes. I got 930 frames and counting, well above the 688 Max Quality JPEGs displayed when a 2 GB memory card is empty. I suspect the large section of sky on the right half of the frames kept memory consumption low. Curiously, the camera started a new directory after 500 which I've never seen before. I've filled cartridges in RAW often but still never in JPEG.

Not one bird appeared, they stayed out back on my squirrel hardened feeder. I did not expect that about 500 frames would have part of a squirrel on the left from where he/she pushed the FEEDER into the Focus Trap.... Still, I got some keepers with one or two squirrels and the feeder in pretty good focus. I like this one with the paw in motion.

I've become a Trap Focus Fan.