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08-26-2014, 04:47 PM   #16
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This whole thing is overly complex for someone starting out. This is my opinion based on nearly 60 years of photography.


Meters are designed to correctly expose the image. Images when meters were being introduced on manual cameras were usually of people, a face or someone on the beach. That meant skin tones were in the middle of the frame usually.


Meters were set to accurately measure the scene but were sometimes fooled by the sky, so spot meters were introduced in the middle of the frame to concentrate on the skin tones.


That was fine when it was manual everything, you set the meter by pointing the centre (spot area) at the most important bit, then recompose and the exposure stayed accurate.


Not so now with auto exposure, composing the image allows the spot meter to fall on the wrong bit, like a jacket, or a tie, or a swimming cosy, or whatever, and the meter readjusts. making the image too bright or too dark.


Spot metering I think you can see really needs full control of the camera to do it right, that usually means manual exposure like all those years ago, or some kind of exposure lock.


Now you know why spot metering has become an advanced technique, you also know how to use it.


I recommend not using it until your advanced enough to use exposure lock or manual control, and just use an averaging method, then adjust for brightness in post.

08-26-2014, 10:37 PM   #17
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Imageman/ all

I disagree wholeheartedly with your responses in general

Nothing has changed in 60 years of photography since meters were introduced into cameras, with respect to exposure, photo composition, and metering ideas. In fact the same issues have been around since the onset of photography.

There is nothing magic or extremely difficult about understanding the different metering modes of a camera, and irrespective of the mode, if you don't understand exactly what the camera is doing, you can make errors in exposure, the main differences between modes, is whether it is you, the photographer who is solely responsible (spot metering) or whether you had the help of some engineer due to the assumptions made during design on what is important in the scene with respect to the overall lighting.

Center weighted metering assumes the most important parts of the scene are centrally located, which is just as wrong, as a portrait usually has the body of the subject centrally located, and unless the subject is a naked Caucasian person, their clothing is usually either darker or lighter than their face, leading to getting their face, under or over exposed because the metering is fooled by the clothing. This is , as correctly pointed out, because metering is based upon Caucasian skin tones being neutral. Also many center weighted patterns are bottom center weighted to ignore the sky contribution in landscapes, meaning that when you go from landscape to portrait mode, the metering of the same scene changes. Don't believe me, take an older film camera, meter on a scene in landscape, and repeat the process with the camera upside down. Note the difference . So it is a real compromise regardless.

Matrix metering is like center weighted, and depending on how the engineer programmed each of the sensors in the matrix to react to bright and dark zones you are at risk of Getting it wrong also, but at least matrix metering was programmed in all cameras to some extent recognize things like point sources of light and very bright vs very dark, but the overall exposure is based upon somebody else's interpretation of what you are trying to do,

So regardless of mode, the missing bit of information the camera needs, is what you are trying to do. There is no MINDREAD.exe function in the camera

By saying go to auto everything as an approach for a beginner because it is too complicated, I think it is demeaning. Beginners are not idiots, they lack experience and training. One of the first things any beginner should learn is exposure. Nothing replaces a good understanding like experimenting with the metering and shooting different lighting situations. Spot metering and manual mode is the best way to do so. Photography is all about understanding and using the lighting available at the time. Auto everything is not the way to learn this. Once lighting is understood, you can then go to the automatic modes, and with the understanding of how they work, and how different situations can fool the metering, you can pick the mode appropriate to the situation.
08-27-2014, 10:06 AM   #18
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Lets not get into a fight Lowell, I think you misinterpret my comments.


I used to think as you do, that beginners can handle learning about all aspects of the camera and its usage including metering modes. I have many times however seen photographers refuse to learn about metering and refuse to have anything to do with manual control or even post processing.


I don't wish to dictate to anyone that they must learn to use spot metering, the fact is that spot metering can be tricky to use when your a beginner, its best to spend a while using an averaging method to get used to controlling the camera in other areas like aperture and shutter speed and their effects and then move on to use spot metering when you are ready. This is linked to the other point I made, that of the auto metering.


You say that nothing has changed in 60 years of photography, that not correct. what has changed is the introduction of auto exposure. Fully manual exposure was normal in the 1970s, spot metering was introduced into fully manual cameras and even then they were found to be tricky to get right in all scenes until you were more experienced.


Manual exposure meant you set exposure using whatever method - spot or average or centre weighted, that you wish or was fitted, then you are free to compose the image. With manual exposure control, using spot metering worked well because after setting the exposure when you recompose the exposure never changed. The result was a well composed image and a well exposed image.


Auto exposure was meant to make things simpler, you don't have to set exposure, the camera does it for you. The trouble is as I said in my post, when you couple auto exposure to spot metering, suddenly as you compose freely, the metering changes wildly and is out of the photographers control, varying from over to underexposure.


If you are lucky spot metering and auto exposure will correctly expose, but as reported in an earlier post, the use of spot metering with auto exposure while shooting a wedding resulted in bad and wrong exposure. Its a gotcha that can strike and ruin the shot if your not experienced and not expecting it. This is too much to ask of a raw beginner who cant handle the camera competently yet.


The only way to correctly expose using spot metering is, as I stated in my post, to use either exposure lock, or manual exposure. These are not the province of a raw beginner so its best to avoid the need for them until more experienced.


If the OP is happy about his abilities to go fully manual then theres no issue. Let him go fully manual. You seem to think that every beginner can move immediately into fully manual. Well I can tell you that very few can and some never want to.


I was teaching a raw beginner in the mid 1970s with a k1000 and let me tell you he had great difficulty coping with a fully manual camera, issues of simply understanding how the controls work and getting decently exposed photographs stumped him for a while. Its hard being a beginner don't assume they can handle everything at once.


Given that you are experienced I would have thought you would recognise that a raw beginner cannot handle fully manual out of the box, they need a little practice to get used to it. Once theyr used to operating fully manual then choosing the metering mode is the next step.


Theres an expression learn to walk before you learn to run. Ive taught people many things, and I can tell you they learn progressively. Spot metering, manual control and exposure lock, are not things you would force a raw beginner to use when you give them a camera for the first time. You let them use the auto modes like aperture priority or shutter priority or even program mode, coupled with averaging metering mode.


Let them produce well exposed images getting used to the effects of choosing the aperture themselves, and then seeing the effects of varying the shutter speed, and then as their confidence grows, introduce them to using fully manual. Once theyr happily using manual exposure, spot metering will be a walk in the park for them.


Im sure the OP will have no difficulty using spot metering if he chooses to, the question is does he want to and does he feel up to it.
08-27-2014, 11:03 AM   #19
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I use spot metering when I see the sky is terrifically white and bright and I know that my subject will be dead center in my frame. Let it overexpose the sky - my subject will be exposed just right, or near enough.

Other than that, I use the default.

I did spot metering this weekend - I was at our local fair and my daughter was on rides, which meant shooting up into the sky. It was a cloud-filled day but bright sunshine behind, so it means overexposing the images were a real possibility. My strategy was to spot meter, and overexpose (with the +- button) slightly. The shots turned out great, with no need for Lightroom to intervene on exposure.

08-27-2014, 02:10 PM   #20
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Rachel, I'm one who thinks videos are a great learning tool. This video should give you hopefully a little more insight. I do suggest you subscribe to this gentleman's You Tube and Go through his free playlists for additional information on things photographically you want to get a better understanding of especially the exposure and lens series. I find he puts things in an easily understandable way. So I hope these help you.

Last edited by Oldbayrunner; 08-27-2014 at 03:03 PM.
08-27-2014, 02:17 PM   #21
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Imageman

No fight intended. I guess the issue for me in a lot of the responses not just yours, is here we have someone in the OP who wants to learn and explore. For me, great. Explain what spot metering is, what it does, the pros and cons, all of which i can agree with in the context of how different people may approach a camara, and then you can recommend that after understanding how it works, and what it does and how to use it, they can make a decision by them selves, or you can suggest they may wish to consider when to start using it or experimenting

I guess what gets me is the posts where people start by saying , it is "for advanced shooters", "too complicated for beginners", "overly complicated for somebody starting out", etc.....

This is even after people are discussing how to meter for silhouettes. They are asking for help and advise on how to use a specific tool useful for what they are doing and we, as a community respond essentially by saying you are doing something beyond your capability.

No fight intended and no more comments about this because it is not the thread topic. Pros and cons of spot metering should be the topic
08-27-2014, 03:02 PM   #22
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QuoteOriginally posted by Just1MoreDave Quote
It [spot metering] is telling you what settings you need to expose that one spot as a middle tone.
I think Dave's answer most directly and simply answers Rachel's question.

She just wanted to know what spot metering is not a tutorial on how to apply it which is another question altogether.
If so then she was not well served by my answer which was too specific, narrow and application specific for what she really wanted to know.
My apologies to her.

Wildman
08-28-2014, 02:46 AM   #23
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QuoteOriginally posted by wildman Quote
For me spot metering is an advanced technique primarily for those that shot in RAW and want to expose for highlights and then later bring up the shadows in PP.

Essentially it's a way of getting the optimum DR out of a sensor without having to resort to exposure bracketing.

For you, no doubt, it sounds complicated but it's not;

First (original) frame straight out of the camera - spot metered on the brightest spot in the frame in this case the light coming through the window and let the shadows fall where they may. This ensures that the highlights are not burned out.

Second frame - same file as above but after PP to normalize the shadows so they appear as they would to the naked eye not the way the camera metered it.

Right now it's probably nothing you want to deal with but later on it's a technique that's well worth mastering given the limitations of camera sensors.
Thank you for the tips! I tried your suggestions today, and they worked.

Original. EV+2.7
EPC-1027

Adjusted
EPC-1028

Pushed to the limit to show how much dark details are stored in the raw image
EPC-1028-2

Again, thanks for the tip!

08-28-2014, 05:12 PM   #24
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QuoteOriginally posted by whk1992 Quote
Thank you for the tips!
You're welcome - good work.
08-28-2014, 07:23 PM   #25
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QuoteOriginally posted by whk1992 Quote
Thank you for the tips! I tried your suggestions today, and they worked.
Note that the success of this technique may vary with the camera you use and the ISO you shoot with.

With my K-x, K-5 and K-3 (and other recent Pentaxes), lifting the shadows up in a big way, particularly from low-ISO's, can often work really, really well. [Thank you Sony sensor!]) But it is not something I would do often with my old K200D, because the image deteriorates quite a lot doing so. It's doable, but you can't push as hard. Other cameras (eg some older Canon's) also start to have problems like really visible banding appearing in the image once the shadows are pushed.

And even with a K-5, if you try and push the shadows hard when working on an image shot at a high ISO (eg ISO 3200 or above), image quality degrades a lot.
08-29-2014, 12:24 AM   #26
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QuoteOriginally posted by rawr Quote
And even with a K-5, if you try and push the shadows hard when working on an image shot at a high ISO (eg ISO 3200 or above), image quality degrades a lot.
In theory yes in practice not so much.

Remember you are metering only on the brightest area of of the frame.
For instance in my example it was a quick hand held shot in the early morning light and the over-all luminosity was low but spot metering on the brightest area of the frame only required an ISO of 200 at f/8@160 sec in TAv mode.
I don't think I have ever had a situation where the proper exposure of highlights, only, required an ISO of much over 400. Possible but in my experience unlikely.
It's hard to imagine a real world situation where the highlights would require an ISO of 3200 for proper exposure.

But your right - a technique best used with a K5 or later sensor.

Here's a quick and dirty example taken just now under a 7 watt florescent night light. View the EXIF for info.
Note: The Ev was 0. Sometimes under these very low light situations you lose more with the added noise by pushing the Hgram to the right than you gain in shadow detail - it's a judgement call by the photographer and depends on the specific situation. After a while you just get a feel for it.

Last edited by wildman; 09-07-2014 at 12:09 AM.
08-29-2014, 05:56 AM   #27
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I ill now throw the cat amongst the pidgeons.


I cannot accept that spot metering in the digital age is contributing much to a well exposed digital image - if you expose correctly using sound digital principles the exposure method becomes irrelevant.


It only is of benefit if you abandon sound and correct principles. Let me explain.


At first there was no metering, then along came Adams and his zone system. Because film had no histogram you had to assess exposure as best you could, and the zone system in effect spread the light and shade across the response curve of the recording medium, effectively achieving a good histogram spread before histograms were even conceived.


Spot metering when it was introduced allowed for the first time precise measurements of all light and shade areas, to fill the response curve and give a better exposure than averaging could.


These techniques were necessary because histograms didn't exist, and you had to get exposure right first time because you didn't know if the exposure was right until after development. If in the digital age the photographer exposed an image and trusted to luck and judgement and never checked the histogram, a spot meter would be important to correctly determine exposure. Because it allows a better judgement of exposure based on elements in the scene, as shown in earlier posts.


But we have the histogram, and correct technique is to expose the histogram to the right, and this does not need a meter once the initial image is captured.


Its worth saying again, expose the histogram to the right.


What this means is, regardless of whether you are using averaging, or centre weighted, or spot metering, you must check the histogram after exposure and make a second exposure having adjusted the histogram for optimum exposure, No other method is correct.


What this means is if your averaging metering reading dictates 1/50th at f8 and your spot meter reading dictates 1/100 at f8, using either of these is almost certainly incorrect but is perfectly adequate for the first exposure, and then examining the histogram reveals that the histogram has not been exposed to the right. So you adjust the exposure accordingly based on the histogram appearance and accumulated knowledge so that it is pushed to the right.


The moment you adjust the exposure to push the histogram to the right you abandon spot metering, or centre weighted metering or averaging metering as a means of determining correct exposure.


The metering mode then, has in the digital age become far less important and is a means now of simply determining the initial test exposure before pushing the histogram to the right as correct technique dictates. In the right hands spot metering can push the histogram closer to optimum than averaging, but relying on spot metering alone breaks the digital rules.


If a digital camera existed with no metering fitted whatsoever, but it had a manual mode and a histogram, any competent photographer must be able using correct digital technique of "expose to the right", to deliver more accurately exposed images than a spot metering system could deliver on its own.


Remember the optimum exposure in a digital camera is not the optimum exposure of film, the two are quite different. Film requires the shades to be spread evenly about the centre of the response curve for the medium. Digital sensors however require the shades to be distributed as close to the maximum as possible, without any clipping. Only viewing the histogram will allow optimum exposure to be achieved, spot metering cannot do it, because spot metering is unrelated to the dynamic range of the sensor due to limitations in its use and variations in brightness in each image.


By all means use spot metering if conditions dictate or you cant retake the shot with optimum settings, but correct method forces us to abandon it for production of the final image.


I believe this is on topic, because the OP asked about spot metering in an attempt to discover the best way of determining correct exposure, and this method is in fact the best, in my opinion.
08-29-2014, 10:31 AM   #28
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QuoteOriginally posted by Imageman Quote
I ill now throw the cat amongst the pidgeons.


I cannot accept that spot metering in the digital age is contributing much to a well exposed digital image - if you expose correctly using sound digital principles the exposure method becomes irrelevant.


It only is of benefit if you abandon sound and correct principles. Let me explain.


At first there was no metering, then along came Adams and his zone system. Because film had no histogram you had to assess exposure as best you could, and the zone system in effect spread the light and shade across the response curve of the recording medium, effectively achieving a good histogram spread before histograms were even conceived.


Spot metering when it was introduced allowed for the first time precise measurements of all light and shade areas, to fill the response curve and give a better exposure than averaging could.


These techniques were necessary because histograms didn't exist, and you had to get exposure right first time because you didn't know if the exposure was right until after development. If in the digital age the photographer exposed an image and trusted to luck and judgement and never checked the histogram, a spot meter would be important to correctly determine exposure. Because it allows a better judgement of exposure based on elements in the scene, as shown in earlier posts.


But we have the histogram, and correct technique is to expose the histogram to the right, and this does not need a meter once the initial image is captured.


Its worth saying again, expose the histogram to the right.


What this means is, regardless of whether you are using averaging, or centre weighted, or spot metering, you must check the histogram after exposure and make a second exposure having adjusted the histogram for optimum exposure, No other method is correct.


What this means is if your averaging metering reading dictates 1/50th at f8 and your spot meter reading dictates 1/100 at f8, using either of these is almost certainly incorrect but is perfectly adequate for the first exposure, and then examining the histogram reveals that the histogram has not been exposed to the right. So you adjust the exposure accordingly based on the histogram appearance and accumulated knowledge so that it is pushed to the right.


The moment you adjust the exposure to push the histogram to the right you abandon spot metering, or centre weighted metering or averaging metering as a means of determining correct exposure.


The metering mode then, has in the digital age become far less important and is a means now of simply determining the initial test exposure before pushing the histogram to the right as correct technique dictates. In the right hands spot metering can push the histogram closer to optimum than averaging, but relying on spot metering alone breaks the digital rules.


If a digital camera existed with no metering fitted whatsoever, but it had a manual mode and a histogram, any competent photographer must be able using correct digital technique of "expose to the right", to deliver more accurately exposed images than a spot metering system could deliver on its own.


Remember the optimum exposure in a digital camera is not the optimum exposure of film, the two are quite different. Film requires the shades to be spread evenly about the centre of the response curve for the medium. Digital sensors however require the shades to be distributed as close to the maximum as possible, without any clipping. Only viewing the histogram will allow optimum exposure to be achieved, spot metering cannot do it, because spot metering is unrelated to the dynamic range of the sensor due to limitations in its use and variations in brightness in each image.


By all means use spot metering if conditions dictate or you cant retake the shot with optimum settings, but correct method forces us to abandon it for production of the final image.


I believe this is on topic, because the OP asked about spot metering in an attempt to discover the best way of determining correct exposure, and this method is in fact the best, in my opinion.
You forgot about the hawks waiting above for the cat.

Exposure to the right means you push the whites almost to the point of loss of detail. Ok, maybe if that's what you want, but, while this can work if you and the subject are stationary, and in agree you can play all you want with the histogram, that method generally DOES not work if you only have one shot at things. Many times in wildlife shooting for example, you don't have a second shot. So let's limit this to stationary things.

Next, consider you are travelling. Add 2 kids and a wife, they won't wait for you to stop and screw around with the histogram. They will get board quickly with dad's hobby .

Now add overcast days, flat lighting situations, exposing to the tight will result in gross overexposure of the entire subject.

Then add the high key, and low key shooters, sunset shooters, and all others that simply want thigs differently, they all need to know exactly where all parts of the scene need to be.


So by exposing to the right, what you really end up with is always having out shoot raw, and screw around with each shot and exposure in some form of post processor.

The point is, you need to understand properly exposure, and understand how to evaluate a scene, decide what's important, and expose that part properly. Simply exposing everything to the right is not the way to go. It is an over simplified generalization.

But if you are happy ok, but it am not sure that is for everyone.
08-29-2014, 11:31 AM   #29
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Hi Lowell,


I have no issue in general with what you say, My remarks are all about what the accepted method is for high quality digital photography, and in many cases time as you say, just isn't there to exploit this method. It is however the recommended method, not by me but the industry and has been quoted many times in this forum.


I did say "By all means use spot metering if conditions dictate or you cant retake the shot with optimum settings", I believe that covers your examples where conditions don't allow the expose to the right method to be used.


I do have a slight issue where you say "Exposure to the right means you push the whites almost to the point of loss of detail. Ok, maybe if that's what you want". That suggests you get an inferior result by doing this, that's not correct at all, the fact is the brightest areas are pushed almost to loss of detail, but that's fine. They are pushed, but not lost, all detail is preserved because its not pushed to loss of detail, So all detail is still present. Where is the issue.


The reason for pushing in this way is that all digital sensors are noisy in shadow areas leading to loss of detail but they render faithfully all details with very low noise at all higher brightness levels all the way up until they clip. So for the best rendering you need to push as much of the image that you can up into these brighter areas where the sensor works best.


This method works with the sensor to render the smoothest shadows with maximum detail while preserving all the image that can be preserved from the deepest shadows to the brightest highlights. This is the reason why this has been the recommended way of working for nearly 20 years, its the best way.


I believe that where we can we should make all efforts to capture the best image possible, only taking shortcuts leading to poorer quality images where we have to. Don't get me wrong spot metering leads to good quality images, but expose to the right leads to as good or better.


I agree with you though, often theres no time for this, and grabshots have to be taken. But even here I don't use spot metering, Your cases that argue for spot metering include grabshots and fast moving subjects, the last time I used spot metering, (3 weeks ago ive been using spot metering for over 40 years) it took time to go through the process. I had the time to spend on it because the subject was stationary.


On the other hand I was taking images at a sport event recently, I didn't have the time to use spot metering, and I didn't have the time to expose to the right either. I had to grab shots as they appeared. Spot metering would have led to many poorly exposed shots.


And what metering mode worked best, and gave me all the shots well exposed reliably and as fast as I could work? averaging metering did, coupled with shutter priority auto mode. That's how you should work with fast action and grabshots, all auto and averaging metering. That's why I originally recommended the OP use auto modes and averaging metering. It works. And I also recommended he use spot metering when hes able to exploit it.


I recently grabbed a contrail shot, the image was strong graphically, and from observing to exposing I had less than 8 seconds to get the camera out switch it on, manually focus. Compose and shoot time for actual composing and shooting, around one and a half seconds. I didn't choose spot metering. It had to be auto all the way.


Bracketing doesn't work either for fast action, I took a series of images in a 100 yard dash, it was over in a few seconds, bracketing and spot metering would have resulted in hardly anything useable. Instead I got loads of good shots. Often its about working fast and being productive.


But all the images I exposed were not the highest quality due to these compromises. So lets not talk about compromises that force us to take poor images, lets talk about taking the very best images, where we have the time to spend on getting it right.
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