[Sigmoid]

Fellow Pentaxians-

My *IST-DS works fine in manual mode with either MF or AF lenses. However, when the AF option is selected, the shutter will not operate. This ocurrs with both of my AF lenses (kit 18-55 and Tamron 18-200).

My favorite local technician suggested lifting the mirror and trying canned air to clean the AF sensor but that didn't help. Another forum indicated that cleaning the contacts at the bayonet mount might cure this problem but that hasn't worked either.

I gave this camera to my wife when I got my K10D but she would like it to work in AF as designed.

Pentax service has not returned my Emails requesting further information. One on-line 3rd party service company estimates the repair at $240 which I think is more than the body is worth. It is still valuable to me as a MF-only backup.

Any suggestions?

Sig

[MrApollinax]

The shutter will not fire unless the focus indicator has locked when AF is engaged. Even if you focus on a distant object at infinity it will not fire?

[Sigmoid]

Yes, that is correct.

[LeoTaylor]

Basic Question to divide the problem in up:

Is it autofocusing? When you press the shutter half way while aimed at various distances does the lens focus?

If no, then the focus motor may be stuck. Try manually focusing while in AF mode (requires a Pentax lens that allows you to overide the motor). If the camera shutter will operate then the AF motor is not working for some reason.

If yes, then the lens is focusing but the camera does not recognize that it is in focus. Look for some option/setting that might cause this. You might consider a total reset. My PDF istD manual on page 126 lists, "Resetting to Default Settings."

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Last edited by LeoTaylor; 05-21-2009 at 10:48 PM. Reason: fixed sentence

[Sigmoid]

Thanks, Leo-

The total reset sounds worthwhile. I can't lay my hands on the owner's manual right now nor find one on the web. Can you please tell me how to perform the reset?

Thanks,

Sig

[ftpaddict]

Here's a link to the manual. Hope it helps.

http://www.pentax.jp/english/support/man-pdf/istds.pdf

[Sigmoid]

Got it!

I'll see if this helps and post results later today.

Sig

[Sigmoid]

Thanks to everyone who has pitched in so far to help me with this problem.

I have reset all settings from the "tools" menu and custom features menu. No change observed.

I did notice that, when the autofocus functions, the motor drives the focus to minimum distance, then to infinity, then stops. With the kit lens set to 18mm (minimum focal length) practically everything is in focus at infinity but the shutter still fails to trip.

Any further suggestions??? Anyone????

Sig

[Sigmoid]

The camera is now fixed. Frank at Camera Wiz in Harrisonburg, VA, just returned the body to me. He found that the return spring for the secondary mirror (which feeds the AF sensor, I think he said) was replaced. For a total charge of $107, including a cleaning and return shipping charges, I got the camera back in two business days and it works like new.

Frank has done work for me since my film winding days and I've always been quite satisfied with his workmanship and his prices. He doesn't have a presence on the Web but he can be reached at:

Camera Wiz
169 Pleasant Hill Rd
Harrisonburg, VA 22801-5775
(540) 434-8133

I don't get anything out of recommending his services, by the way, except karmic rewards

Sig

[LeoTaylor]

The camera is now fixed.

I'm glad the problem is resolved.

This thread is so old I did not recall posting on it in May.