Erratic exposure - K30

Oricman · 07-16-2016, 12:32 PM

I was testing my 55-300 zoom and didn't realise the ISO was on the variable setting rather than a fixed ISO. The cameras decided to select 1600 iso which produced very over-exposed shots.
My exposures can seem quite variable. Consecutive shots of the same subject can come out quite differently so it seems the camera doesn't adjust settings to produce the right exposure.
Similar things happen when using flash. It doesn't seem to adjust the flash to the settings used so can produce over or under-exposed images.

I can get a good exposure by adjusting the settings using a bit of trial and error but a subject may have moved on by then.

This wouldn't think this is how the camera should behave(?) Does this happen to anyone else???

AlexBW · 07-16-2016, 02:20 PM

What exposure mode is the camera set to? If spot mode, then small changes in composition can have very big exposure changes.

(Note that some K30 cameras develop an aperture control problem, but this results in variable, badly underexposed photos. There are several threads about this)

stevebrot · 07-16-2016, 02:30 PM

Originally posted by Oricman

I was testing my 55-300 zoom and didn't realise the ISO was on the variable setting rather than a fixed ISO. The cameras decided to select 1600 iso which produced very over-exposed shots.

If you have over-exposed shots, it is not because of auto-ISO. In all but M, X, and B modes the exposure follows the meter reading. As AlexBW noted, use of the spot meter for ordinary shooting* is a common cause of variable exposure and may be what is causing your problems if that is your practice.

Is there any chance you can share an example image? An out-of-camera JPEG (EXIF intact) is preferred.

Steve

* Spot metering is a special purpose tool that allows fine exposure control. The catch is that appropriate use requires active involvement by the photographer and experience with the technique.

Oricman · 07-17-2016, 11:46 AM

I tend to shoot in center weighted rather than spot. I'll post something later. The recent ones are still on the camera.

Oricman · 07-17-2016, 01:15 PM

Looking at the info on the camera I've found it set to spot metering. Good call AlexBW & Stevebrot !
I've no idea how it got to be on that setting - it's one I rarely use. It's actually quite a relief to find a definite cause.

I've gone back to the shots I took the day before and they too are on Spot metering. I don't know how it happened to be on there - but at least it's something that is easy to correct!

Thanks for the replies. I'm a pillock!

reh321 · 07-17-2016, 01:51 PM

Originally posted by Oricman

Looking at the info on the camera I've found it set to spot metering. Good call AlexBW & Stevebrot !
I've no idea how it got to be on that setting - it's one I rarely use. It's actually quite a relief to find a definite cause.

I've gone back to the shots I took the day before and they too are on Spot metering. I don't know how it happened to be on there - but at least it's something that is easy to correct!

Thanks for the replies. I'm a pillock!

For my style of shooting, the third setting {which values each point equally} works best, partly because it provides the most stability.
YMMV.

07-16-2016, 12:32 PM	#1
Oricman Guest	Erratic exposure - K30 I was testing my 55-300 zoom and didn't realise the ISO was on the variable setting rather than a fixed ISO. The cameras decided to select 1600 iso which produced very over-exposed shots. My exposures can seem quite variable. Consecutive shots of the same subject can come out quite differently so it seems the camera doesn't adjust settings to produce the right exposure. Similar things happen when using flash. It doesn't seem to adjust the flash to the settings used so can produce over or under-exposed images. I can get a good exposure by adjusting the settings using a bit of trial and error but a subject may have moved on by then. This wouldn't think this is how the camera should behave(?) Does this happen to anyone else???

07-16-2016, 02:30 PM	#3
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by Oricman I was testing my 55-300 zoom and didn't realise the ISO was on the variable setting rather than a fixed ISO. The cameras decided to select 1600 iso which produced very over-exposed shots. If you have over-exposed shots, it is not because of auto-ISO. In all but M, X, and B modes the exposure follows the meter reading. As AlexBW noted, use of the spot meter for ordinary shooting* is a common cause of variable exposure and may be what is causing your problems if that is your practice. Is there any chance you can share an example image? An out-of-camera JPEG (EXIF intact) is preferred. Steve * Spot metering is a special purpose tool that allows fine exposure control. The catch is that appropriate use requires active involvement by the photographer and experience with the technique. Last edited by stevebrot; 07-16-2016 at 04:55 PM.

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07-16-2016, 02:20 PM	#2
AlexBW Pentaxian Join Date: May 2014 Location: Oslo Photos: Albums Posts: 394	What exposure mode is the camera set to? If spot mode, then small changes in composition can have very big exposure changes. (Note that some K30 cameras develop an aperture control problem, but this results in variable, badly underexposed photos. There are several threads about this)

07-17-2016, 11:46 AM	#4
Oricman Guest	I tend to shoot in center weighted rather than spot. I'll post something later. The recent ones are still on the camera.

07-17-2016, 01:15 PM	#5
Oricman Guest	Looking at the info on the camera I've found it set to spot metering. Good call AlexBW & Stevebrot ! I've no idea how it got to be on that setting - it's one I rarely use. It's actually quite a relief to find a definite cause. I've gone back to the shots I took the day before and they too are on Spot metering. I don't know how it happened to be on there - but at least it's something that is easy to correct! Thanks for the replies. I'm a pillock!

07-17-2016, 01:51 PM	#6
reh321 Pentaxian Join Date: Nov 2014 Location: South Bend, IN, USA Photos: Gallery \| Albums Posts: 23,179	Originally posted by Oricman Looking at the info on the camera I've found it set to spot metering. Good call AlexBW & Stevebrot ! I've no idea how it got to be on that setting - it's one I rarely use. It's actually quite a relief to find a definite cause. I've gone back to the shots I took the day before and they too are on Spot metering. I don't know how it happened to be on there - but at least it's something that is easy to correct! Thanks for the replies. I'm a pillock! For my style of shooting, the third setting {which values each point equally} works best, partly because it provides the most stability. YMMV.