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11-13-2013, 11:49 AM   #31
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Everything I've found about active d-lighting indicates that it will adjust exposure by "up to 1 stop". This is not the same thing as preventing blowouts. It simply helps reduce blowouts. Its real intent is to compress the contrast of a scene so that more detail can be seen in both highlights and shadows. A lot of people like it and use it but they also complain that it increases noise in the shadow areas.

11-13-2013, 11:58 AM   #32
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QuoteOriginally posted by ChopperCharles Quote
I'm not talking about highlights being cut by finagling with ISO, I'm talking about the camera actively adjusting the exposure settings AT THE TIME OF CAPTURE such that the highlights are not blown in the first place
As was previously stated in this thread, there are only 3 aspects to exposure, ISO, Aperture and Shutter Speed. This ADL therefore adjusts 1, 2 or all 3 of these based on some algorithm that meters for the highest EV in the frame.

This would be no different than a human dialing down the EV comp by -1, -2 or even -3. The difference is the camera does it for you. Would this keep the rest of the bird from being a black blob? probably not? as norm mentioned.

It could be great to never overexpose a picture, but if it throws 70% of the image into underexposure land, you bring in noise and shadow detail loss and that doesn't necessarily make for a better image.

If you never want to blow out a highlight again, dial the EV down to -3, it'll give you the same result, but you'll get a whole lot of underexposed images and/or a whole lot of underexposed areas in your images. A camera can have all the bells in whistles in the world, and prevent all the highlight blowouts, but you ARE going to sacrifice the other end (shadows)

Until a camera has a liquid flux neutral density field that automatically adjusts to ONLY highlighted areas and leaves unimpeded light flow from normally exposed areas in the frame, cameras won't be able to handle this situation (example photo) ADL or no ADL.

If you want to continue taking high contrast harsh shadow highlight images, you need to learn how to properly meter them, shoot them and how to utilize HDR in PP.
11-13-2013, 12:18 PM - 1 Like   #33
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QuoteOriginally posted by ChopperCharles Quote
Can you please go back and read this thread a bit before making such a quick (and completely off-base) posting? I'm talking about ACTIVE Dynamic Lighting, and using the example as implemented on Nikon cameras.

On a Nikon camera, if you turn ADL on, the EXPOSURE WILL CHANGE. I'm not talking about highlights being cut by finagling with ISO, I'm talking about the camera actively adjusting the exposure settings AT THE TIME OF CAPTURE such that the highlights are not blown in the first place -- not "fixing" the blown highlights after the fact with digital processing. The Nikon system effectively dials in exposure compensation as you're shooting, in order to ensure that highlights are never blown. That's a COMPLETELY different solution. Instead of trying to fix blown highlights with digital manipulation, ADL simply adjusts exposure so that it doesn't blow the highlights in the first place.

On a Nikon, you can easily see this. Point the camera at a dark object so that it almost completely fills the frame, and have a bright object (like a lamp) in the corner of the frame. With ADL off, the camera will expose for the entire frame. The dark object will be exposed correctly and the light will be completely blown out.

But turn ADL on, and the aperture and shutter speed will change, and the EXPOSURE will be adjusted such that the light will not be blown out. The exact same framing will result in different shutter speed and/or aperture value when ADL is turned on. This will of course under-expose the dark object, but for the situations I need ADL for, this is not a problem.

Charles.
Charles, how is this fundamentally different than Pentax's implementation of Highlight Correction? Yes, Pentax cameras are changing the exposure at the time of capture when it's detected that it needs to do so (obviously only if you set HC to On). Accomplished by altering ISO.
11-13-2013, 10:45 PM   #34
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1) The ISO still shows exactly the same in the exif. (just noting this)
2) There's some ISO manipulation going on behind the scenes, but it's still only one stop. Highlights still blow.
3) I want a setting where the camera will expose for highlights.
4) While the photo I posted is easy to correct for, by dialing in exposure compensation (which I did in subsequent shots), when photographing moving subjects in constantly changing stage lighting, I don't have the luxury of chimping, and there is no histogram in an OVF.
5) I'm not a Nikon fanboy. I'm explaining that the technology I want is present in some form or another.
6) I was originally asking whether that same technology was available in any Pentax bodies. But everyone and their mother responded without bothering to read about what i was really after, or judge me, or tell me a different way of doing things, or imply that I have no idea what I'm doing, or even tell me I'm wrong for wanting what I want. But none answered the actual question.
7) After all this, my guess is that no, what I want doesn't exist, and Nikon cameras probably don't even do exactly what i want. They're likely not even close to aggressive enough.

What I want is a setting in the camera that will expose for highlights, and thus never blow them. This obviously wouldn't work in all situations, but it will work in several of the shooting situations I encounter. But since it doesn't exist, there's not really a point to continuing this thread.

Charles.

11-14-2013, 06:13 AM   #35
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QuoteOriginally posted by ChopperCharles Quote
1) The ISO still shows exactly the same in the exif. (just noting this)
2) There's some ISO manipulation going on behind the scenes, but it's still only one stop. Highlights still blow.
3) I want a setting where the camera will expose for highlights.
4) While the photo I posted is easy to correct for, by dialing in exposure compensation (which I did in subsequent shots), when photographing moving subjects in constantly changing stage lighting, I don't have the luxury of chimping, and there is no histogram in an OVF.
5) I'm not a Nikon fanboy. I'm explaining that the technology I want is present in some form or another.
6) I was originally asking whether that same technology was available in any Pentax bodies. But everyone and their mother responded without bothering to read about what i was really after, or judge me, or tell me a different way of doing things, or imply that I have no idea what I'm doing, or even tell me I'm wrong for wanting what I want. But none answered the actual question.
7) After all this, my guess is that no, what I want doesn't exist, and Nikon cameras probably don't even do exactly what i want. They're likely not even close to aggressive enough.

What I want is a setting in the camera that will expose for highlights, and thus never blow them. This obviously wouldn't work in all situations, but it will work in several of the shooting situations I encounter. But since it doesn't exist, there's not really a point to continuing this thread.

Charles.
You seem to be asking for a feature that doesn't exist on any camera ever sold by any manufacturer, including Nikon. Maybe that's why no one has answered your question to complete satisfaction. I do agree with you on your last point about continuing this thread.
11-14-2013, 07:48 AM   #36
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Set your Pentax to EV -2, or if you're shooting into the sun, or EV -3. The reason no one has a feature guaranteed to not blow any highlights, is it would ruin a lot more images than it saves. Those are the settings that will do what you want. Your camera will still compensate for changing light conditions and constantly underexpose everything. It's really sad, but exposing for highlights by definition, under exposes everything else. WIth a K-5 you should be able to pull up some detail out of the shadows.

If you look at a lot of theatre photography, that's the way they are expose, often with a lot of darkness behind the actor in the spotlight. I expect, the metering system in the K-3 would also be a lot more accurate than the k-30 just because of the additional (and smaller) metering points. SOme combination of spot metering and -1 or -2 EV might also work if you keep your subject centred.

What you are really asking for is some kind of HDR function that will give you a normal exposure in the mid tones, an under-exposed highlights , and boosted shadows from one exposure. I think, technically it could be done…but to date, it hasn't as far as I know. A K-30 should be awesome for that because of the ability to recover shadow detail, a K-x , not so much. But if you look at the guys who have posted images from bars etc, you are going to get those wonky colours from the stage lighting.Especially in recovered shadow detail. Some things just can't be helped.

It's impossible to discuss what Nikon does, because you don't actually know what it does. And neither do any of us. But it is possible that they have produced a camera that is really good at handling theatre lighting. The would be the kind of niche product that you buy the camera to do the job if that's what is important to you.

Just like if you want to rake the leaves in your garden you buy a leaf rake. You can use garden rake, and you might wonder while using your garden rake, "why doesn't someone make a rake that can be both a garden rake and a leaf rake?" That in no way will help you get your leaves rakes, nor will complaining about it on the internet.

OK, I've had my say, (a couple of times), I'm out of here.
11-14-2013, 01:23 PM   #37
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It seems clear that there is no blowout proof auto exposure out there. Given that, you might try manual mode.

A lot of people get the idea that because the light changes then they have to change the exposure but this is not necessarily true. (Similarly, they use auto white balance to compensate for indoor lights, etc. But you don't have to do this either.)

By setting your camera to daylight white balance and fixing the exposure manually, you will get WYSIWYG images, which is what you really want, right?

So for a stage play, you can be pretty sure that the lighting is controlled by the lighting director to be acceptable to all those dark adapted eyes in the audience. So there won't be massive amounts of variation. The main white spotlight will probably be a good baseline for the rest of the lighting.

The way I would handle this is to set daylight white balance and then manual exposure based on that white spotlight and keep that exposure throughout. (I'll bet this spotlight intensity is quite standard and unchanging too, so a setting could be used from one show to another, at least for starters.) When the scene changes to different colour lights or dimmer lights and different locations, then that is what the director had intended and if you keep your exposure fixed, you will get what the director intended. So your images will be WYSIWYG.

Also, you can easily change your manual setting with just a click of a wheel if need be on the fly.
11-14-2013, 01:42 PM   #38
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QuoteOriginally posted by gbeaton Quote
It seems clear that there is no blowout proof auto exposure out there. Given that, you might try manual mode.

A lot of people get the idea that because the light changes then they have to change the exposure but this is not necessarily true. (Similarly, they use auto white balance to compensate for indoor lights, etc. But you don't have to do this either.)

By setting your camera to daylight white balance and fixing the exposure manually, you will get WYSIWYG images, which is what you really want, right?

So for a stage play, you can be pretty sure that the lighting is controlled by the lighting director to be acceptable to all those dark adapted eyes in the audience. So there won't be massive amounts of variation. The main white spotlight will probably be a good baseline for the rest of the lighting.

The way I would handle this is to set daylight white balance and then manual exposure based on that white spotlight and keep that exposure throughout. (I'll bet this spotlight intensity is quite standard and unchanging too, so a setting could be used from one show to another, at least for starters.) When the scene changes to different colour lights or dimmer lights and different locations, then that is what the director had intended and if you keep your exposure fixed, you will get what the director intended. So your images will be WYSIWYG.

Also, you can easily change your manual setting with just a click of a wheel if need be on the fly.
A very practical approach you outlined. Additionally, the theater may be able to provide Charles with a white balance temperature that he can set on the camera ahead of time.

11-19-2013, 01:11 AM   #39
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For burnt out highlights why not use 3 or 5 shot burst mode with +/-1 EV setting, I often do this. Then you can manipulate the best image in LR, and you can even muck around with HDR.
11-19-2013, 10:28 AM   #40
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QuoteOriginally posted by ChopperCharles Quote
Can you please go back and read this thread a bit before making such a quick (and completely off-base) posting? I'm talking about ACTIVE Dynamic Lighting, and using the example as implemented on Nikon cameras.

On a Nikon camera, if you turn ADL on, the EXPOSURE WILL CHANGE. I'm not talking about highlights being cut by finagling with ISO, I'm talking about the camera actively adjusting the exposure settings AT THE TIME OF CAPTURE such that the highlights are not blown in the first place -- not "fixing" the blown highlights after the fact with digital processing. The Nikon system effectively dials in exposure compensation as you're shooting, in order to ensure that highlights are never blown. That's a COMPLETELY different solution. Instead of trying to fix blown highlights with digital manipulation, ADL simply adjusts exposure so that it doesn't blow the highlights in the first place.

On a Nikon, you can easily see this. Point the camera at a dark object so that it almost completely fills the frame, and have a bright object (like a lamp) in the corner of the frame. With ADL off, the camera will expose for the entire frame. The dark object will be exposed correctly and the light will be completely blown out.

But turn ADL on, and the aperture and shutter speed will change, and the EXPOSURE will be adjusted such that the light will not be blown out. The exact same framing will result in different shutter speed and/or aperture value when ADL is turned on. This will of course under-expose the dark object, but for the situations I need ADL for, this is not a problem.

Charles.
You might want to look further into the issue, as some of your assumptions are not on the mark. In fact, the Nikon and Pentax highlight preservation systems are almost identical. The Pentax highlight correction system absolutely does apply to the RAW and any processed image (assuming that you use a full-featured RAW converter that reads the direction). As so many on these forums have repeated an untruth, I decided to test it out shooting RAW on the three bodies I have that offer it. The camera underexposes, and then applies a (very good) roll-off curve at the high end where detail would have been lost. My preference for use on the K30 and K-01 is to leave the compensation in "Auto" although this can become an issue in high contrast situations where light is low - forcing higher ISO settings (I shoot a lot of TAV). In those situations, I sometimes would prefer to turn off HC and live with some blow out rather than lose a stop. The shadow compensation function, indeed, is a "digital" fix after the exposure - and would only alter the JPEG output. I don't see a real need for it unless someone really doesn't want to do any post-processing.

Bottom line, my testing indicates that 95% of blowout is corrected by using the highlight correction function. In normal daylight conditions, I strongly prefer its use shooting RAW to resorting to any other type of manipulation, such as dialing in underexposure (which affects the entire exposure range and requires more PP work). The correction instructions are read properly in LR and Capture One. Possibly some of the lower quality converters do not read it.
11-19-2013, 02:34 PM   #41
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QuoteOriginally posted by ScooterMaxi Jim Quote
You might want to look further into the issue, as some of your assumptions are not on the mark. In fact, the Nikon and Pentax highlight preservation systems are almost identical. The Pentax highlight correction system absolutely does apply to the RAW and any processed image (assuming that you use a full-featured RAW converter that reads the direction). As so many on these forums have repeated an untruth, I decided to test it out shooting RAW on the three bodies I have that offer it. The camera underexposes, and then applies a (very good) roll-off curve at the high end where detail would have been lost. My preference for use on the K30 and K-01 is to leave the compensation in "Auto" although this can become an issue in high contrast situations where light is low - forcing higher ISO settings (I shoot a lot of TAV). In those situations, I sometimes would prefer to turn off HC and live with some blow out rather than lose a stop. The shadow compensation function, indeed, is a "digital" fix after the exposure - and would only alter the JPEG output. I don't see a real need for it unless someone really doesn't want to do any post-processing.

Bottom line, my testing indicates that 95% of blowout is corrected by using the highlight correction function. In normal daylight conditions, I strongly prefer its use shooting RAW to resorting to any other type of manipulation, such as dialing in underexposure (which affects the entire exposure range and requires more PP work). The correction instructions are read properly in LR and Capture One. Possibly some of the lower quality converters do not read it.
As for theater lighting, this is very challenging. If you can get some cooperation by metering directly off a face or light clothing in the spotlight before the shoot, that should help determine how much exposure you can allow in without blowout. If not, bring a longer lens that allows you to fill a spotlighted area that you want on the high end of the scale to obtain a good initial meter reading. Shoot manually based on the spotlighted/frame filled highlight reading.
11-19-2013, 03:50 PM   #42
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Or ask DimC how he does it.

http://www.flickr.com/photos/dimc-photos/10949863183/

Scroll down to the bottom of this page.
11-19-2013, 04:20 PM   #43
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QuoteOriginally posted by ScooterMaxi Jim Quote
You might want to look further into the issue, as some of your assumptions are not on the mark. In fact, the Nikon and Pentax highlight preservation systems are almost identical. .
"ADL moves your zero meter reading in all but the Low setting. Each progressively more aggressive setting moves it until it is ultimately changed by a full stop on extra high. Thom Hogan puts the exact numbers in his D90 manual, I think they are probably in the D7000 manual as well.

If you want this feature but want the true meter reading keep it on Low."

Reference with test images (including shutter speed, aperture, iso readings): Does Active D lighting change the exposure? - Photo.net Nikon Forum

Pentax highlight correction does not change the meter's zero reading, so they're not the same.

Charles.
11-19-2013, 05:09 PM   #44
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My understanding is that this feature simply means the camera shoots at one stop lower ISO than is displayed then it boosts the shadows to produce the JPEG. Typically the manufacturer "lies" in the JPEG and claims it shot at the camera displayed ISO, in fact the ISO used was lower.

This is the same effect as shooting -1 EV and boosting in PP except you can at least shoot in RAW this way and produce a better final result.

There’s no magic here.
11-19-2013, 05:19 PM   #45
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QuoteOriginally posted by ChopperCharles Quote
"ADL moves your zero meter reading in all but the Low setting. Each progressively more aggressive setting moves it until it is ultimately changed by a full stop on extra high. Thom Hogan puts the exact numbers in his D90 manual, I think they are probably in the D7000 manual as well.

If you want this feature but want the true meter reading keep it on Low."

Reference with test images (including shutter speed, aperture, iso readings): Does Active D lighting change the exposure? - Photo.net Nikon Forum

Pentax highlight correction does not change the meter's zero reading, so they're not the same.

Charles.
They are similar, whether or not what they do can be seen by the user. Nikon has a bit more implementation latitude. Why not do a test? Why not read an expert review, such as this one where it is explained?


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