How-to-shoot with pentax K20d?

<p>Procedure, to shoot with 50 mm M or 50mm A pentax lens?</p>

<p>"Aperture Ring Accept" to get the metering right. Check the menus for it. After that, dial it in, and rock out.</p>

<p>For the A lens, all you need to do is set the lens on A. You select aperture through the dials on the camera.<br>

You'll get focus confirm if you leave the camera in AF. (At least on the *ist DS2, the camera will refuse to take a picture if the manual focus lens isn't focused accurately in AF mode. I find that obnoxious.)<br>

To use a non-A lens, you need the "aperture ring accept". You also need to push the "green button" to stop down the camera and meter. Stop down metering accuracy can be less than ideal.<br>

This is why used Pentax-A lenses fetch a considerable premium over their Pentax-M cousins.<br>

You may also find you want to buy a Katz-Eye focusing screen if you want to focus accurately with a manual-focus lens. The stock screens are optimized for brightness with slow lenses, not for ability to manually focus.</p>

<p>John S, the very design concept that does not allow the shutter to fire with a MF lens without focus confirmation when the camera is set in AF mode, also grants the use of trap focus, which can be a valuable tool. It is also valuable as a focus aid in some conditions. The option of switching the camera to MF, which allows the shutter to fire if focus is not confirmed is there as well.</p>

<p>I have found the metering using the green button with my "M" lenses to be quite good, if keeping my aperture range from wide open to f/11. So wide and mid apertures appear to be accurate, but stopped down more not very accurate.</p>

<p>An "A" lens does provide a much better range of functions.</p>

<p>As a new K20D user I have kept a FA 28/2.8, an A 50/2.8 and an M 135/2.8. I have been experimenting with stopped down (Green Button) metering in both A and M modes and in comparision with a digital spot meter. (A mode and Spot are in good agreement)<br>

I have found (with these lenses on the K20D) that is indeed true that stopped down metering wide open (f2.8 in these cases) gives exposure values close to those at f2.8 in Auto mode. However, stopped down metering at F5.6, f8.0 and f11 gives exposure values 50% to 300% higher than Auto or Spot. I can't see any way of getting close with stopped down metering other than at wide open.</p>

<p>David, I'm not under the impression that green-button stop-down metering is expected to work in any mode other than M. I assume by 'A' mode you mean 'Av' mode. Your A50 should work fine in any mode, assuming the aperture ring is in position 'A'.</p>

<p>Andrew, thanks for that. Yes, I should of said I shoot in manual. My use of A mode refered to the setting on the lens (if it had one) not on the camera. Sorry for the confusion.</p>

<p>I don't think anyone has mentioned this yet, but forgive me if they have.</p>

<p>Even when you're in manual focus mode, the AF confirmation light in the viewfinder will light up when your camera thinks you've achieved the proper focus point. Or, at least, that's how it works on my K10D + 50/1.7 M. </p>

<p>Thanks to each of you for the info, about 3 months back,I had a blood clot and haven't been the same,and haven't been able to been able to figure this K20d out yet........Jim</p>