*ist D Auto Exposure

Anybody comment on this please?

There are no obvious malfunctions with the camera.

However, I'm not sure about the precision of the exposure in auto modes however. Can't be certain but I feel my Z10 is better and it has only 6 zones.

It affects simple views with land and sky and when using TTL flash. Quite often it gets it spot on!

The latest firmware has been installed and this may have helped. Not sure yet.

Otherwise this camera is fantastic.

Here are my observations with the *istD...

It's really easy to switch to spot metering by mistake and not notice. I've wondered a few times what's going wrong, so I'm trying to get into the mental habit of checking the metering switch before use (it's switched over pulling it out of the camera bag )

Regarding TTL flash, if you mean P-TTL flash (with the popup), then yes there are some issues that haven't been entirely pinned down. It seems the preflash exposure gets it wrong if there's a large amount of white in the scene, and then the real exposure underexposes.

Digital CCD has a completely different response to light compared to negative film (especially). Negative film is very forgiving. Digital is much less forgiving when over exposing. It seems the *istD goes for the "safe" option most times and slightly underexposes. (Technically, film and slide is logarithmic in response, while CCD is linear.) This is just something you have to live with (Canon and Fuji users too have to learn to adjust some of the time.)

If you need a serious shot, don't forget that RAW mode gives a lot more lattitude too, especially if you have the benefits of Photoshop CS. You can claw back loads of details from underexposed areas that is not possible in JPG mode. If the shot is particularly difficult (such as backlit macro images), I find it helpful to switch to manual, get the exposure in JPG mode, then switch to RAW for the real shot.

It's a whole new learning curve, but one that's been hugely rewarding

Hope that helps!
Matt

Thanks - your comments are very interesting and go some way to explaining it.

I would say it underexposes more than over.

Have to remind myself from the manual what the P-TTL is!

The on camera flash is just popped up and used in auto green. I also used the older ???400 Pentax big flash.

I have almost exclusively used slides on the Z10. My own made up solutions (I am a chemist) have been used to process them and high consistency was achieved. The Z10 got it wrong on some shots.

The *ist D is fine. The exposure is not a big deal - you can bracket at no extra cost! You can usually re-take the shot until happy.

Ammonia,

P-TTL is Preflash- Through-The-Lens metered.

The *istD fires a quick flash to guage exposure, sorts out what it's going to do then fires the main flash. If you look really carefully you'll just about discern there are two flashes, not one.

The AF400 does only TTL. It's only the AF360FGZ that does P-TTL (and sometimes wish it wouldn't so you can slave normal flashguns with a magic eye.)

Regards,
Matt