How to use your camera's Spot Meter for excellent landscape images

This blog is primarily intended for DSLR or 'bridge camera' users. It will also help if you own an advanced 'point and shoot' digital camera which has a spot metering mode built into it.This will help you get the most out of a powerful metering mode available in your camera but very rarely used.

Spot Metering is available in all DSLRs, most of the so called 'super zoom' or 'bridge' cameras and many regular point and shoot cameras. To find out if your camera has a Spot Metering mode, refer to your camera's user manual While with your manual, you may also like to find out how to activate spot metering on your camera.

Unfortunately most users, including DSLR users are not aware of the correct technique or true potential of spot metering. If used incorrectly, the Spot Metering mode can produce disappointing results. Once you understand the correct usage, this mode can work wonders, particularly in high contrast lighting situations.The most commonly used metering mode, the Matrix mode (also known as Evaluative or Pattern mode on some camera brands), gives reasonably accurate exposure for  a scene with average contrast. However, it has serious limitations when dealing with a high contrast situation. Also, the exposure indicated by the Matrix Metering may vary depending on which part of the scene the camera is pointed at. While this metering relies on the built-in database in the camera, the exposures are often inaccurate and inconsistent in difficult lighting conditions.

Before embarking on a detailed discussion on Spot Metering techniques, it would be appropriate to have a basic understanding of exposure measurement. To put it in  oversimplified terms, the metering system perceives a subject to be of neutral grey reflectance value. Let us say this value is 18% grey.(for the sake of simplicity I am not entering into a discussion on why neutral grey is 18% and not 50% or whether digital camera meters are calibrated to 18% grey or 14%) The camera's exposure meter then evaluates the brightness of the subject and measures the degree of deviation from the 18% grey and gives a reading which will make the subject appear 18% grey. So if the subject is brighter than 18% grey, it will suggest (or automatically set) a lower exposure to render the subject 18% grey. Similarly if the subject is darker than 18% grey, the meter will indicate higher exposure. If the subject is actually of average grey reflectance, the metering system will work perfectly well. However, if the subject is brighter or lighter than mid grey, the meter may give a wrong reading. The exposure recommended by the meter may over expose a black suit to render it grey or underexpose snow to make it appear grey. The tonality  of the subject has an impact on the exposure metering. The Matrix or Evaluative metering system of a modern camera has built in algorithm to compensate for such anomalies and can be depended upon to give a reasonably good exposure in low contrast situations. Under high contrast lighting conditions one cannot rely on the matrix metering to give consistent exposure or to nail the exposure exactly as you visualize in your creative mind.

When to use Spot Metering;

Most photographers I know rarely change their metering mode from the default Matrix (Evaluative) mode. In modern cameras the Matrix mode has considerably evolved with algorithm fine-tuned to a wide variety of situations. An average photographer may rarely find it necessary to use any other mode. However, just like the Auto White Balance (AWB)  in most of the cameras, the evaluative metering is often unpredictable, inconsistent and often inaccurate. Just a slight shift of the camera angle, to include a bit more (or less) of the sky significantly impacts the exposure. This is more often the case in contrasty lighting or when the dynamic range of the camera is stretched to its limits. Very often one resorts to HDR (High Dynamic Range) to accommodate the dynamic range. Unfortunately the HDR images have a flat, grungy look, which may not be realistic. The point I am trying to make is that very often we resort to HDR even when it is not required. In this situation, if the exposure is properly evaluated taking into account the brightest highlights and the darkest shadows we may be able to capture the full tonal range that the camera is capable of. Modern DSLRs and even point and shoot cameras have a reasonably good dynamic range. Our aim should be to fully utilize the dynamic range of the camera. By advanced spot metering techniques we can squeeze in the maximum range the camera is capable of without resorting to HDR.  In very contrasty lighting, where we want details in the darkest shadows and the brightest highlights Spot Metering is the best mode.

Spot Metering Techniques
  
There is a bit of a learning curve involved in using the Spot Metering mode. I hope this blog helps you in getting started. While spot metering is often used in product and portrait photography to measure lighting ratios, I will be concentrating on using the spot metering mode for landscape photography as this will be of interest to many of my readers.

It is important to note that Spot Metering mode works differently in different cameras. In most of the Nikons the spot metering area is the focus point (the small rectangle in the view finder used as focusing point). In most Canons, Spot Metering area is only the central focus point. In Nikon, therefore, the Spot Metering point can be moved around in the view finder. For other cameras please refer to the instruction manual. Another important point to note is that unlike a dedicated hand held spot meter like the Sekonic L758 series, the spot metering area is not constant. It will depend on the lens being used. The Spot will be wider if a wide angle lens is being used and narrows down with a telephoto lens. So unlike the L758 with a 1 degree spot, you may expect a spot of 10-3 degrees depending on the lens. This information is very important if you want to take a reading from a very small area.

There are three different techniques for using the Spot Metering Mode to get excellent and consistent results. After taking a spot meter reading as described below, you need to lock that exposure using AE lock button or manually set the exposure, recompose and shoot. If you are not sure about the method of taking exposure reading, please refer to your camera's user manual.

1.) Metering off a known neutral grey area
2.) Metering off a grey card
3.) Using the zone system

1.) Metering off a known neutral reflectance area:
As  discussed earlier, an exposure meter measures the deviation from 18% grey and adjusts the exposure to give a neutral reflectance value. If, therefore, we take a reading from a known mid reflectance area of our scene, we will get a correct reading. By taking a reading from a known neutral area the exposure of all parts of the scene in the same lighting will automatically fall in place. If, for example, a bride in white dress and  groom in black suit are standing on a lawn, we will get correct exposure if we take the spot reading off the green grass as it known to be of around 18% reflectance. We can identify objects in a scene with reflectance value  of or around mid grey. Keep in mind these objects need not necessarily be grey in colour. They can be of any color as long as they reflect 18% light. I know you must now be wondering how can one identify an object with mid grey tone (18% grey). Relax. You need not really worry about the percentage of reflectance. For this method just meter off any object which is neither too dark nor too light. Some objects which can be used for spot metering are grass, leaves, stones and parts of clothing which are neither too bright nor too dark. You may find many objects in your natural surroundings which represent neutral grey. One important thing to keep in mind is that the object you are using for spot metering should be in the same lighting as your subject.

2.) Metering off a grey card:
This method is more accurate than the one discussed above. This method is essentially the same as the one above but here instead of selecting a natural object with neutral reflectance, we use a calibrated grey card. Grey cards are readily available and these give a more accurate reading. Just place a grey card in the same light as your subject and take the reading off it using the spot metering mode in your camera. It is a good practice to carry a grey card in your  camera bag.

3.) Using the Zone System:
This , by far,  is the most useful method for landscape photographers. The results from using this method is truly rewarding. I strongly recommend my readers to go through this section carefully as I have immensely benefited by this method.  The Zone System is a fairly complex subject and there are many books entirely devoted to this. A full discourse on zone system is beyond the scope of this blog. I will try to cover this in a nutshell. This may not be the exact replica of the Zone System as propagated by the master landscape  photographer Ansel Adams but I have tried to simplify as much as I can. So here goes. The entire tonal range of a scene is divided into 11 segments (0 to X). Zero represents the darkest area of a scene. This is an area so dark that it contains no details. On the opposite end we have Zone X. This is the brightest area of the scene. It is so bright that it is totally washed out and contains no details. The entire spectrum of luminance comes between these. Zone 1 is the darkest area with some discernable details. On the the other end we have Zone IX which represents the brightest part of the scene with some details.Each Zone represents one stop of exposure. As we move from Zone 0 to Zone X we are increasing the exposure by one Stop for each zone.For those who are familiar with histograms in their cameras Zone IX represents the right side of the histogram just before highlights are blown out. (The tonal range represented by Zones 0 to X are represented on a Histogram as 0 to 255) In the 11 segment Zone scale (Zone 0 to Zone X) zone V represents the mid point or 18% reflectance value. In the Histograms this is midpoint represented by 118 in the scale of 0-255. The range of tones a camera can accommodate without blowing off the highlights or clipping shadows is known as its Dynamic Range

The Zone Scale- Zone V represents 18% Grey

Our aim is to capture the maximum tonal range in our image with discernable details in the darkest shadows and brightest highlights and to optimally utilize the dynamic range of our camera. Basically we want to capture everything from Zone I to Zone IX (remember, zones 0 and X have no details). How do we do this? One way to achieve this is to meter off a neutral grey object. We can do this by any of the methods described above. However, we may not be having an accurate 18% grey card handy. Finding a mid grey object to meter from may be too subjective to be accurate. It is, much easier to identify the brightest area of our scene. As we have discussed earlier whatever we meter is exposed for 18% reflectance. In other words whatever we meter is placed in zone V. Now consider this. If you meter the brightest part of your image, say a white cloud or snow, the camera's exposure system is going to place that in Zone V which is a mid grey. Now we do not want our white cloud or snow to be mid grey. Moreover by placing the brightest part of the scene at Zone V everything which is darker gets pushed further to the left and the shadows may become devoid of details. This also means that we are not utilizing the full dynamic range our camera is capable of yielding. We want the cloud or snow to be white with details. In other words we want to place them in Zone IX or as close to it as possible.

Modern DSLRs have considerable dynamic range. For a mid range DSLR the range can be upto around 7 stops (4 stops below and 3 stops above the normal) The dynamic range of a high end DSLR may be as high as 10 stops (5 stops on either side of normal). Point and shoot cameras may have a dynamic range of upto 4 stops (2 on either side of normal)

Now coming back to our scene. When we are shooting our landscape lookout for the brightest highlight and the darkest shadow (you can do this only by spot metering) . If they are within the dynamic range of your camera go ahead and shoot. If your scene is beyond the dynamic range of the camera, try to protect the highlight from blowing out. This is how you do it in practice. Meter the brightest part of the image where you want some details. The reading will place this part in zone V which is mid grey. Now we want our snow or white cloud to be white, not grey. We want to push this as much to the right as possible. If you are using a mid range DSLR you have a dynamic range which can extend 3 stops above zone V. You can safely expose for Zone VIII. Let us take a practical example. Suppose you are capturing a landscape with hills, greenery and clouds.You want to capture as much detail as possible in the cloud without blowing out. Take a spot meter reading from the brightest part of the cloud. Say this reading is f/22 (for whatever shutter speed and ISO you are working with). Now f/22 will render the cloud as middle grey. Your mid range DSLR has a dynamic range upto 3 Stops above zone V. You can safely expose 3 stops more to reach zone VIII. Go ahead and open up 3 stops from F/22 so your correct exposure for this shot will be f/8.With this exposure your dynamic range will be optimally utilized. Let us take another example to make this concept clear. This time we will keep the aperture constant and change the exposure using shutter speed as this is the preferred method in landscape photography due to depth of field concerns. Suppose the metered exposure for the cloud is 1/1000 sec. This will place the sky in zone V. Our camera has a dynamic range of 3 stops above the normal. So, we can go upto zone 8 by decreasing the shutter speed by three stops. the correct exposure will be 1/125. This is also known as ETTR or exposing to the right. This will not blow out the highlights and protect details in them. The shadows will also be protected from clipping.

A good exposure makes optimal use of the dynamic range of the camera.   

The dynamic range varies from camera to camera. You may have to experiment with your camera to determine its range. As a general rule, upto two stops in either direction is safe with most modern cameras.
I hope you have learnt something new about spot metering. The best way to master this mode would be to set your camera in the spot metering mode and try out the three methods of spot metering. Keep notes on your exposure as you go along and critically evaluate your exposure. Fine tune your method based on your equipment and the desired results



  

Calibrate your monitor without any hardware

If you are serious about your photography, you must ensure that your monitor is properly calibrated. The importance of display calibration in digital photography can not be overemphasized. There is a lot of difference in the way our eyes perceive a subject and the the way your camera captures. Again there is a wide difference in what your camera captures and what your monitor displays or what your printer prints. One may go at lengths to get a customs white-balance in the camera using proprietary white balance tools like the Expodisc or the Colorchecker Passport but if the monitor is not properly calibrated all that effort goes waste. Each digital camera records colours differently and to make matters worse your monitor interprets colours differently. It is not just colour that is of importance. The brightness and contrast of the monitor also have an important bearing on the way our image appears on our monitors. If you find that your prints are consistently dark, it means that your monitor is too bright.  A red, pink or purple flower may appear different on your monitor from what you actually saw.

If you edit your images in Lightroom or Photoshop (or any image editing software for that matter), it is all the more important to calibrate your monitor. If your monitor is not properly calibrated you may end up adding more contrast to an already contrasty image because the contrast setting of your monitor was very low to start with. You may end up saturating colours that were already saturated or adjusting exposure on a perfectly exposed image.

Placement of your monitor, quality of ambient light and the glare on your monitor screen also play an important role on the accuracy of your display. Ideally the monitor should be placed in a room where the quality of ambient light does not change much. The monitor should not face a window or a direct source of light as this could result in lower contrast. The area surrounding the monitor should neither be too bright nor too dark.

Calibrating a monitor is actually a very complex procedure and involves the use of dedicated hardware and software. These calibration devices, unfortunately, do not come cheap. They cost upward of  US $100. Not every photographer would like to spend that kind of money on display calibrators. Even if you seek professional help to get your monitor calibrated, it does not work out cheap as you have to recalibrate most of the monitors at least once a month.

Is there a simple and cheap way to calibrate your monitor? Well, there is! Buried deep inside your Windows or Mac menus there is a rather crude means of calibrating your monitor. Crude, because it depends on your eyes and can be tricky. Nevertheless, it is better to use this method rather than not calibrating your monitor at all. This may not be as accurate as the hardware based solutions but will be adequate for most amateurs.

I will try to explain this procedure in detail for Windows based PC using screen shots. The procedure for Apple Mac is similar and I have touched upon it at the end.

Calibrating display on a Windows based PC:

These screen shots are based on a Windows 8.1 System but the procedure is basically the same for all versions of Windows.

1. First you need to access the display settings. You can reach there by going to the the Control Panel/Hardware and Sound.

Fig 1

 2. Next, select 'Display'

Fig 2

 3. Select 'Adjust resolution' from the left panel.

Fig 3

4. Select 'Advanced Settings'

Fig 4

5. Select 'Color Management'

Fig 5

6. Again click 'Color Management'

Fig 6

7. In the next window, select the 'Advanced' tab

Fig 7

   8. Select 'Calibrate Display'

Fig 8

9. Next few screens (figures 9-21) are self explanatory. Just follow the instructions on the screen and move on to the next screen (by clicking on the 'Next ' button on the bottom right). Before you begin you should know where the brightness and contrast settings of your monitor are located. These are usually soft-touch buttons on the bottom  or on the right side of the monitor.

Fig 9

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Fig 21

The steps represented by Figures 11-20 are crucial to the accuracy of this process and should be carried out with care. The sliders in steps represented by Figures 13 and 20 should be used very carefully. Normally, only very small amounts of correction are required. If overdone the Gama and Color Balance of the monitor can get skewed. If you are using a very old monitor which has no brightness or contrast control, you can skip this calibration in the step represented by figure 14, above. In the last step (Fig. 21) you can see the before and after results by clicking the Previous and Current calibration buttons. If you are not happy with the new results you may click Cancel to go back to the original settings.

Calibrating display on a Mac

The procedure for calibrating a Mac display is by and large the same. To get to the calibration menu follow this route on a Mac: System Preferences/ Display/Color/ Calibrate. Follow the on-screen instructions.
Conclusion:
Usually, after completing the calibration process the screen will look slightly warmer. It may take some time to get used to it but believe me, colors , contrast, brightness and Gama values will be more accurate than before. You will find noticeable difference in skin tones, textures and sky colour.

I will be covering hardware based monitor calibration in a subsequent blog. For now enjoy your calibrated display!
Please do send your feedback and comments. I value them.   

Think before you click!

I would like to apologize to my readers for the delay in  publishing this blog. The delay was partly due to setting up, calibrating and trying out my new Sekonic  L758 lightmeter. I will cover the advantages of using a light meter like this in a future blog.

In the good old days of film photography, one was more careful about good composition and exposure, primarily because of the cost of film and processing. Depending on the occasion, one would buy films in the minimum possible quantities. May be a roll or two for a long vacation, or a birthday party. It was not uncommon to have a roll with pictures of both, the New Year and Christmas of the same year. Cameras were rarely taken out from the cupboards. While taking pictures care was taken to ensure that the precious film was not wasted. Special care was taken to ensure proper composition and exposure. Those with simple cameras without auto exposure or metering, would carefully read the instruction sheets which came with the film rolls to determine the correct exposure or follow the 'sunny 16' rule. All this was important because, unlike the present,  there was a long delay before one could see the results and the cost involved.

With the proliferation of digital photography all that has changed. The quest for perfection has got diluted somewhere down the line. As results can be seen instantaneously and cost of memory storage is low, the emphasis on proper composition and exposure seem to have taken the back seat. Taking multiple exposures of the same scene seems to be the order rather than exception. Even though the technology provides   excellent tools for exposure control and composition, not many use them. Many still think that by buying costly equipment, their images will automatically turn out  better. I have seen many who have advanced bridge cameras or even DSLR s but do not know anything about exposure compensation, shutter priority or aperture priority. Many are not even familiar with the working of the auto focus systems in their cameras.  All that they care to know is to press the shutter and expect the camera to do all the heavy weightlifting for them. Infact one gentleman asked me if the Tv mode on his Canon Powershot SX50HS bridge camera was intended for capturing images off the TV screen! Unfortunately very few bother to read the user manual. While my future blogs will surely cover the technicalities of exposure I would request the readers to try out the following over the next few days:

1. Read the instruction manual of your camera. If you have lost the camera manual, you can easily download the same from the website of your camera manufacturers' website. In particular read about the different exposure modes available on your camera and how to set up your camera for the exposure mode you want.

2. Consider each exposure as precious (as in the film days!). Think carefully before pressing the shutter release button.

3. Switch your camera to Aperture Priority mode (A or Av mode) or Shutter Priority mode (S or Tv). In other words move away from the P or any fully automatic mode. Learn more about depth of field. Try out shooting with different aperture, starting with the widest your camera provides. Do not get confused with the numbers, small numbers indicates large apertures and vice versa . f/3.5 is a larger aperture than, say,  f/8. Take pictures of a flower or plant at different apertures and see what happens to the background. See how you can freeze a moving object by using a fast shutter speed of deliberately blur it by using a slow shutter speed. If you have a camera (or a cell phone) which has no means to control aperture or shutter speed, do not worry, move on to the next step. I will cover depth of field in a future blog.

A proper exposure is essential to bring out details in the shadows and highlights.In this picture even a slight overexposure would have resulted in washed out sky.

4. Before pressing the shutter button think about the final image. Will the image convey to its viewer what you intend it to convey? Is the lighting right? Is the composition balanced? Is the background distracting? Is there any unintended object in the frame? (This could very well be your camera bag or a lens cap!) Is the horizon straight and appropriately placed for the image? How is the sky? An overcast grey sky devoid of any detail can adversely impact an otherwise perfect image. You will be surprised that by moving a few steps forward or backward or bending a little can make a lot of difference to the image.

It is essential to ensure proper exposure for the sky. At the same time the details on the statue are clearly visible

5.) After you get back to your computer, evaluate your image critically. Your camera's LCD screen is too small for a proper evaluation. See if the exposure is correct. Has the image been composed well? Are there any distracting elements in the image? Is the horizon straight? Does your portrait suffer from red eye? Is the image free from any colour cast? Is the focus tack sharp? Is there an unintended motion blur? Any evidence of camera shake? I will surely cover many of the issues in my blogs but you can surely evaluate your pictures and plan for better images in future.

Colors, and rows of boat visually lead your eyes to the church in the background. In landscape photography it is essential to have interesting foreground

6.) While you should try to get your image right while shooting, do not shy away from post processing. All images coming out from a digital camera can greatly benefit from post processing in an image editor. This is true for images from a cell phone camera or even the most advanced DSLR. You do not require an advanced image editor like, Photoshop, Lightroom or Aperture to edit your images. Simple image editors like Picasa are sufficient for basic image editing. You may also try out the image editing software that might have come with your camera. While in the image editor, you may adjust the exposure, brightness and contrast. Remove R'ed Eye', straighten your horizon and crop your image for  better composition.

7) Store your images meticulously. You should be able to retrieve any image without difficulty. Storage devices are becoming cheaper. Do consider investing in a high capacity external hard drive exclusively for your images. You may like to classify and name your folders appropriately for quick retrieval. You may also like to have a folder exclusively for your best images. This will serve as a great learning tool to enhance your skills.

8) Consider printing some of your images. There are many online print retailers. Nothing like having your own prints framed and decorating your wall.

9) You can easily show your images to your friends on any modern TVs. For most LCD/LED TVs an imaged cropped to an aspect ratio of 16:9 will appear as full screen without any black crop band above and below your image. You will find 16:9 crop as one of the crop preset in any image editing software including Picasa.

Contrasting colours and a the dirt track visually lead you into the frame

10) Share your images with your friends and relatives through on line albums like Picasa and Flicker or through social networking sites like Facebook.