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02-16-2012, 08:05 AM   #16
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I'm not sure if you've ever heard of the following book, but its well worth its price, and explains this and many other phenomenon. Understanding Exposure by Bryan Peterson is easy reading, and full of great pictures and exposure info.

02-16-2012, 08:56 AM - 1 Like   #17
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QuoteOriginally posted by Philoslothical Quote
What lens was that taken with? The aperture used isn't in the EXIF, so I'm assuming it's a M series or earlier. Are you sure the lens is functioning properly for stop down metering? You should be shooting in M mode and using the green button to meter when using manual lenses. Av (which this was shot in) is frequently off by a stop or two with manual lenses, so underexposed shots like this aren't a surprise.
What he said. Use M mode with the green button. Av mode with a M42 lens on your camera may result in 2-2.5 stops underexposure at apertures wider than about f/4. M mode on the K-r (K-7 and K-5 too) has provides a special "non-A contact" meter algorithm for when these lenses are detected that is not available in Av mode.


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02-16-2012, 09:02 AM   #18
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QuoteOriginally posted by reivax Quote
Not sure why the EXIF data didn't upload, but this one was taken with my DA 55-300. This is one of the worst cases. This was actually taken at about 6 pm in the summer, but it doesn't start to get dark in the summers until about 8 pm. Shot F-11, 1/500 ISO 400.
This photo is properly exposed, at least from the meter's point of view. If you want to retain shadow detail at the risk of the highlights blocking, you must apply some exposure compensation. It also helps to shoot RAW and adjust the curves in PP using a tool such as Lightroom. There is generally quite a bit more data in the capture than what can be supported by your monitor or printer.

As for the EXIF...there is EXIF data with the photo. There is just not very much. The program that generated the file (gd-jpeg?) stripped the rest out.


Steve
02-16-2012, 09:13 AM   #19
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QuoteOriginally posted by mattt Quote
I'm not sure if you've ever heard of the following book, but its well worth its price, and explains this and many other phenomenon. Understanding Exposure by Bryan Peterson is easy reading, and full of great pictures and exposure info.
Excellent recommendation. Once you have an understanding of what the meter "sees" and how the sensor/film reacts to light, exposure is less of a mystery.


Steve

(...There is also Ansel Adams, "The Negative" should you be interested in a more involved discussion.)

02-16-2012, 05:43 PM   #20
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QuoteOriginally posted by stevebrot Quote
What he said. Use M mode with the green button. Av mode with a M42 lens on your camera may result in 2-2.5 stops underexposure at apertures wider than about f/4. M mode on the K-r (K-7 and K-5 too) has provides a special "non-A contact" meter algorithm for when these lenses are detected that is not available in Av mode.
Steve
This is very helpful info, Steve! I was just starting to get used to correcting the exposure (by 2/3 to 1 IL) when shooting with M lenses and using the AV button. I'll re-assign "Green Button Function" to the Green button!
02-16-2012, 07:46 PM   #21
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QuoteOriginally posted by mattt Quote
I wouldn't call it inconsistancy - its performing as expected - exposing for a value of 18% is what it is designed to do. Notice the bottom left side of these screen captures.... the Histogram tells the story here. Camera is performing admirably.

I hope you dont mind, but it is the most direct way to explain what is going on and confirm that the camera is working correctly.
I don't mind at all. I still have a tough time understanding histograms. I've had understanding exposure recommended so many times to me and I don't know why I keep putting off buying it. I think I'm going to have to bite the bullet and buy it.

Thanks. I really appreciate the attention to detail.
02-16-2012, 07:59 PM   #22
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Re Histograms.... think of the left side as all your dark colours and shadows, and the right side as your whites and lights. If you get great big peaks piled up at either end, your clipping... meaning the sensor is not able to record the data beyond the low limit, or high limit, so the info is lost. you want to have "tails" at the edges, and more data in the middle. You can also turn on the clipping alarm feature in the display... dark shows blinking yellow, light shows blinking red.

If you want to get an idea of how to pick middle grey's out of your scene to meter from, look at this...



if you have no grey, use EV compensation to over expose bright scenes (snow, sand etc), or under expose dark scenes (Black Cats, or horses etc, this shot recently taken at dusk looked quite washed out when PP'd to be "properly" exposed)




Post is your friend... it really makes things pop. A simple curve adjustment, and de-noise is the difference between above, and below

Last edited by mattt; 01-07-2016 at 05:34 PM.
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