E-PL1 - when using 'A' or 'S' exposure is not accurate on LCD

[RichStant]

Just got my E-PL1, and working out how to use it In general I'm really enjoying it, however I can't work out where I'm going wrong here. If I put it into manual mode, when I change ISO, aperture & shutter speed, the brightness of the LCD image changes to match what I'll get with those settings. However when I put it into aperture or shutter priority modes, that isn't the case - I can set the shutter really fast & the ISO really low, so that a picture is really dark, but the image on the LCD is normal brightness. It makes it hard to work out the optimal settings when I'm playing around. I tried setting the rec button to preview, and pressing that, but it doesn't make any difference.

How do I get the brightness of the image in the LCD to reflect the settings I've chosen when in A & S modes?

 

[Brian Mosley]

I suspect you've got live view image boost on... Don't have my camera to hand, but there's an option to normalise the live view image brightness regardless of exposure. You need to find this and turn it off.

Will post the location later if you can't find it.

Cheers

Brian

 

[RichStant]

Unfortunately live view boost is already off. Turning it on produced the same affect that I see in A & S modes, in M mode. Turning it off makes the LCD show the correct image when in M mode, but leaves A & S modes unaffected.

 

[RichStant]

I've done some more investigating. Basically M mode works as I'd expect - changing exposure/aperture/ISO affects both the exposure compensation reading & the LCD brightness. However in 'S' and 'A' modes, changing ISO/exposure does not affect the LCD, and it doesn't affect the exposure compensation. For example if I manually change the exposure compensation in 'S' mode, then it alters the brightness of the LCD screen, and will change aperture up to a point, but after it reaches the minimum aperture, the exposure compensation keeps going up, and the LCD brightness keeps going up, but the pictures stay the same (obviously, since the aperture can't be altered any further)!!. Conversly no matter what shutter speed I select, the exposure compensation remains in the centre, despite the final picture brightness varying!

 

[Streetshooter]

The cameras consider A & S modes as semi auto.... the camera decides 1/2 of the equation. M mode overrides the camera and lets you see the effect.
I think that the camera will not show adjustments unless your in M mode.

Remember that in A & S mode the camera will adjust exposure to meet your choice, thus the reason no show on the screen.
In M Mode, you select both parts and even if you move the camera, you can see the change because the camera's brain is on vacation....

 

[squeegee]

yes it's also true on the e-p1. It's caught me off guard a few times before. It would have been nice to have shown it too bright or too dim on the live view since it really is too bright or too dim. The problem happens when you hit the limit of the "other" variable, ie. in A mode when your shutter is already at 1/4000 it flashes the setting to show you it's hit it's limit but sometimes if you're not paying attention you don't notice the little flashing number (compared to the whole picture).

 

[DavidB]

Err... you're judging exposure by how bright or dark the LCD is??????
So when you're in a dark room you end up with dark exposures (otherwise the LCD would seem too bright) and when you're out in bright sunlight you end up with overexposed images?

Use the histogram! That's what it's for!

 

[squeegee]

Err... you're judging exposure by how bright or dark the LCD is??????
So when you're in a dark room you end up with dark exposures (otherwise the LCD would seem too bright) and when you're out in bright sunlight you end up with overexposed images?

Use the histogram! That's what it's for!

yes you're right, using the LCD to judge exposure is problemmatic.

Having said that, the histogram isn't all that great either (or I'm using it wrong which maybe entirely possible). I find if I centre the histogram it is almost always over exposed by about 4 stops. If I smoosh about 2/3rds of the histogram to the left, it's "about" right, but it's still varies by about 2 stops (either way depending on the shape of the histogram and my bad judgement).

How exactly are you using the histogram?

 

[DavidB]

There is no single "correct histogram". If you're shooting a high-key image it should be bunched up to the right. If you're shooting a detail in the shadows then it should be further to the left (or you could Expose To The Right and then wind it back in post). Incidentally, ETTR is more useful with RAW shooting than with JPEG.
Also, as mentioned elsewhere it's sometimes important to check the separate R/G/B histograms rather than just the "luminance" histogram.

I usually shoot in M, and sometimes in Av (can you tell I have a Canon upbringing? ). My G1 will show me a simple live histogram, but even without that you can check the histograms when chimping. This is my standard behaviour when using my EOS bodies.

Try shooting a variety of subjects "as-metered" (with the Exposure Compensation at 0). Look over the results and over time you'll get a feel for the histograms and how they relate to the images in front of you. Review the histograms on the camera's LCD before you erase the card, and review them in Lightroom or whatever you're using.
Eventually you'll get a feel for which shots need -ve EC (e.g. shooting the shadows and stopping the camera making them too bright) and which need +ve EC.

 

[RichStant]

yes it's also true on the e-p1. It's caught me off guard a few times before. It would have been nice to have shown it too bright or too dim on the live view since it really is too bright or too dim. The problem happens when you hit the limit of the "other" variable, ie. in A mode when your shutter is already at 1/4000 it flashes the setting to show you it's hit it's limit but sometimes if you're not paying attention you don't notice the little flashing number (compared to the whole picture).

Thanks for letting me know it's 'as designed'. You're right - everything is ok as long as the camera can compensate for your shutter settings be altering the aperture, but when you go 'off the scale' it doesn't alter the lcd or exposure comp accordingly.

As to using lcd/histogram - I'm sure you're correct, and that is a better way of doing things. But when you're learning the ropes the lcd brightness is a good, quick way of getting a feel for which settings you should be using & when. I also find the histogram tends to be very spread out which doesn't really help much!

It's also rather incongruent because the lcd brightness/exposure comp change correctly in manual mode, so it's reasonable to expect them to change when in other modes too, even if you are 'off the scale'. It's just strange & unexpected behaviour. As long as I know it does it there are ways round it (i.e. get used to the histogram!).

 

[RichStant]

Err... you're judging exposure by how bright or dark the LCD is??????

Use the histogram! That's what it's for!

The trouble is, after just having a play, it turns out the histogram doesn't work in A & S modes either! In M mode the histogram moves accordingly, but in A & S modes if you take the shutter speed too high or low, the histogram just sits there in the middle. So there's no way to use the histogram in A/S modes to see how bright/dark your image is, if you're off the scale of where the camera can compensate your settings.

 

[DavidB]

If you're at the limits of the shutter or aperture values, of course the histogram isn't going to move: the exposure isn't changing. Maybe I'm not understanding your symptoms properly.

If you're previewing a "normal" scene in A mode where the shutter speed isn't too fast, does the histogram not move up/down as you change the exposure compensation?

 

[RichStant]

If you're at the limits of the shutter or aperture values, of course the histogram isn't going to move: the exposure isn't changing. Maybe I'm not understanding your symptoms properly.

If you're previewing a "normal" scene in A mode where the shutter speed isn't too fast, does the histogram not move up/down as you change the exposure compensation?

OK, I'm in 'S' mode. If I look at a dark scene, and start to reduce the exposure time, the aperture opens to compensate, and LCD brightness/exposure comp/histogram stay in the middle. As I carry on reducing the exposure, the aperture opens as wide as it can before I reach the fastest shutter speed. Therefore I can carry on reducing the exposure further, resulting in an image that is too dark. However neither the LCD, the histogram or the exposure comp show this - according to all 3 of those, my image brightness is correct (EV0), yet when I take the picture it is almost black.

 

[DavidB]

Agreed, in that circumstance I would expect that the histogram would shift to the left as you reduce the exposure.

Note that reducing the "exposure time" does not reduce the exposure (as the aperture opens to compensate). When you reduce the actual exposure (either with negative compensation or by hitting the limit of your aperture) I would expect the histogram to show it.

 

[RichStant]

If anyone's interested, I ended up sending an email to olympus - they said:

"I know what you mean but I can only confirm that this is how this camera model works."

A bit annoying, but at least I know I'm not using it incorrectly! Are other cameras the same, or is this a quirk of the olympus models?

 

[Streetshooter]

Hold on.....

Back a few post I explained but maybe not clearly enough.

The camera always defaults to CORRECT EXPOSURE in A or S mode. That's why you don't see anything change. Because the camera adjust to get correct exposure as you change any setting...it equals the exposure equation.....

In M mode...you are altering the exposure the way YOU want so you see the changes.....

 

[RichStant]

The camera always defaults to CORRECT EXPOSURE in A or S mode. That's why you don't see anything change. Because the camera adjust to get correct exposure as you change any setting...it equals the exposure equation.....

No - you are correct that the camera will attempt to compensate for (eg) decreased shutter time by opening the aperture, resulting in the exposure staying constant. However beyond a certain point the aperture will not open further, yet the shutter time can still be further reduced. This will result in a lower exposure, because the camera cannot adjust enough to compensate. However the LCD/histogram/EV do not alter to reflect this.

 

[Streetshooter]

Is this issue having an effect on your work?

 

[Preston]

On my EP-1 the behavior is also as described. In S or A mode the LCD shows no preview of exposure, but in M, and also in P mode, it does show it.

I find it very useful to use the LCD to check exposure because I often place light sources or backlighting in the frame that will necessarily be clipped, and at that point a histogram is useless. The LCD helps me to see where and how much is clipped as I adjust the compensation.

I cannot imagine that this is anything but a bug in the firmware. Or is there some other explanation why you can preview exposure in program mode but not in aperture priority mode?

 

[RichStant]

Is this issue having an effect on your work?

It's not the end of the world, although it would be useful if it worked as I expected (i.e. as it does in M & P modes). Maybe if more people emailed olympus about it, there's a chance of a fix.