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View Full Version : Is my EM10's light meter off?


snerkler
13th May 2014, 02:31 PM
As some will know I've just bought an EM10, and I'm wondering if my camera's meter is off causing it to overexpose? I shoot in aperture priority and noticed that most of my shots had -0.7 or -1 exp comp. When composing the shot I use a combination of the look on the LCD, histogram and knowledge of the shot to set the exposure. My histograms in lightroom and aperture also look OK.

So I've just run a quick test, using wide (ESP) metering and centre weighted, and my 45mm f1.8, 20mm f1.7 and 14-42mm EZ, all using bracketing set to 0, -0.7 and +0.7 ev. On all shots, -0.7 looked the best, and this reflected in the histogram. I've tried both indoor and outdoor shots.

Have others found this, and is it a quirk of the camera, or is my meter off?

bilbo
13th May 2014, 03:11 PM
Best if you post some shots with the exif data intact. Then we would be able to judge better.

snerkler
13th May 2014, 05:21 PM
Best if you post some shots with the exif data intact. Then we would be able to judge better.

Thanks, I'll see what I can do. I'm not sure whether photobucket keep EXIF in tact? I don't really want to clutter up my flickr.

Also, I've thought about metering off a grey card to see what that gives, if the histogram isn't central I guess it's not metering right?

Posted this question elsewhere and it seems others have a similar experience, although one guy says his consistently underexposes :confused:

snerkler
13th May 2014, 05:26 PM
Here's an example of the histogram of one of my shots.

0ev
http://i1353.photobucket.com/albums/q673/snerkler/Random%20Forum%20Pics/0ev_zps325e488d.png

-0.7ev
http://i1353.photobucket.com/albums/q673/snerkler/Random%20Forum%20Pics/-07ev_zpsdaabaa69.png

On the first one you can see quite a lot of clipping, highlighted by the white triangle. Also, when you view these images on my camera on the highlights/shadows screen you can see a lot of blown highlights (marked red and flashing) with images at 0ev. Again, this is the same across various scenes, indoor or outdoor.

bilbo
13th May 2014, 07:22 PM
Thanks, I'll see what I can do. I'm not sure whether photobucket keep EXIF in tact? I don't really want to clutter up my flickr.You can upload them to this site. See the front page RHS panel for how.

snerkler
13th May 2014, 07:35 PM
You can upload them to this site. See the front page RHS panel for how.

Thanks. I haven't got time to watch the video right now, but you can download some samples from my dropbox here. As I say this is just one example of many.

https://www.dropbox.com/sh/pi7qk2ye6vk6msq/AADK4cnrhZTZ8fJs0knWu2RKa

SteveJ
13th May 2014, 07:58 PM
To me the 0ev seems the best exposure. It's one of those difficult images for a camera to expose correctly as there is a lot of reflected light from the wet paving stones.

Steve

snerkler
13th May 2014, 08:22 PM
To me the 0ev seems the best exposure. It's one of those difficult images for a camera to expose correctly as there is a lot of reflected light from the wet paving stones.

Steve

Really, -0.7 looks best to me. Sorry if this is a silly question but I assume your monitor is calibrated?.
Have you checked the histogram, lots more blown highlights on the 0ev and also shows lots more blown highlights on the LCD monitor of the EM10 :confused: Using LR I have to bring back the highlights much more on the 0ev. I appreciate what you say about the 'difficult' scene, but my A77 doesn't appear to have these issues.

This is another example, although I think -.07ev is too dark, and 0ev too light. Perhaps -0.3ev would have been better. However, in LR -0.7ev needs no exposure or highlight adjustment, whereas 0ev does. Also, there's nothing in the blacks/shadows part of the histogram at 0ev, as though everything has shifted to the right. At least with -0.7 the luminosities fill the whole histogram (see histograms post #4)

https://www.dropbox.com/sh/3wcih7wccv17jvy/AABiNmDCU-1B3_dn5PKnTkXja

Edit: FYI I have posted this question on another forum and it appears others have the same issue of the EM10 overexposing :(

Edit 2: I think looking at the links on photobucket the pics look slightly darker than the originals so might be worth while downloading to compare?

snerkler
14th May 2014, 08:23 AM
Hmmm, I'm still not convinced that the Olly isn't overexposing. I've done a comparison with my Sony HX9v (A77's away have the AF modules fixed) and the Olly is overexposing by 0.7ev compared to the Sony. Granted the frames aren't identical so the test isn't brilliant, but the olly has more sky in which I would expect to bring the exposure down if anything, which it doesn't. Now I know a lot say that exposing a scene isn't the best way of doing things, but it's how the camera behaves in the real world which is important to me, not how it does it in a test scenario. On these shots even the brick work of the house looks overexposed to me at 0ev :(

https://www.dropbox.com/sh/r7l3kc6krxt1x1l/AADX-2HyEd4MvqhcdHykpidza

Ian
14th May 2014, 08:37 AM
I think you need a better test shot than the one you have posed as there is a very large area of darkness in the side of the sofa which dominates half the frame. Even so, the three shots looks about right to me given the subject matter.

Which metering mode is the camera set to? Are you using Auto Gradation mode?

Ian

snerkler
14th May 2014, 09:07 AM
I think you need a better test shot than the one you have posed as there is a very large area of darkness in the side of the sofa which dominates half the frame. Even so, the three shots looks about right to me given the subject matter.

Which metering mode is the camera set to? Are you using Auto Gradation mode?

Ian

Thanks. Have you seen the last ones comparing my Sony's exposures? Clearly shows the Olly is exposing differently.
What's auto gradation?

snerkler
14th May 2014, 11:26 AM
I have just had a play with my camera settings and changed my exposure shift which appears on first attempts to have solved my exposure issue. Despite what the manual says, you can actually see the effects of exposure shift in the monitor too so your final shot looks the same as it does prior to taking the shot :) The settings are a little confusing though as they are 1/6, 2/6 etc, how does this translate into 0.3ev, 0.7ev etc? Can I just use simple maths that 1/6 is 0.17ev, 2/6 is 0.33ev etc? I've found that 3/6 works best and appears on first tests to solve my issue :)

Re auto gradation, would someone mind explaining what this is please and where I find it in my menus as I don't seem to be able to find it?

Thanks for all the help guys, the exposure shift seems to be the answer. I'll see how I get on.

Ian
14th May 2014, 01:40 PM
Thanks. Have you seen the last ones comparing my Sony's exposures? Clearly shows the Olly is exposing differently.
What's auto gradation?

Auto Gradation is a mode that boosts the shadows and protects highlights. It's an image processor mode that only applies to camera JPEGs but it's been noticed that exposure is affected (which means RAW files are also affected) but the exposure shift is usually under-exposure.

I was curious to know if you were using matrix, centre-weight or spot metering?

Ian

snerkler
14th May 2014, 02:06 PM
Auto Gradation is a mode that boosts the shadows and protects highlights. It's an image processor mode that only applies to camera JPEGs but it's been noticed that exposure is affected (which means RAW files are also affected) but the exposure shift is usually under-exposure.

I was curious to know if you were using matrix, centre-weight or spot metering?

Ian

OK, so it's confession time. It appears that I've made an Olympus newbie rookie mistake. After looking into this gradation thing my camera was set on high. Since changing it to normal my exposures have been what I expected, and without the need for exposure shift :o In my defence I've never had this gradation option before ;)

In answer to this question, for the garden shots it was matrix metering. But I also had the same with centre weighted too.

Bikie John
14th May 2014, 03:35 PM
Glad you're sorted. No need for a hair-shirt confession - these cameras have so many options and experience is the best teacher!

John

byegad
25th May 2014, 03:03 PM
LOL. As if none of us have left some obscure setting unchecked when looking at poor shots. If I had £1 for every time I've done this I'd own several more cameras and lenses!

byegad
10th June 2014, 09:12 AM
Further to this topic.

After owning the camera for a few days I seemed to be getting slightly over exposed images on all my shots, irrespective of focus area. I changed the EV preset down by 1/6 EV in all focus areas and seem to have solved the issue.

Now if only I could do the same with my Panny G6, which is about 1/6 EV too dark on every shot! Sadly the G6 doesn't seem to offer the option.