Botanical Gardens Falls Artistic Version

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To explore what it would mean to live fully, sensually alive and passionately on purpose, I have to drop my preconceived ideas of who and what I am. – Dawna Markova

This quote of Dawna Markova reminds me that creativity requires giving up our usual and comfortable way of doing things. Erich Fromm similarly stated “Creativity requires the courage to let go of certainties.” Charles Dickens, in the same vein, said “The important thing is this: to be ready at any moment to sacrifice what you are for what you could become”.

I am a person who, after developing a certain level of competence or “success”, enjoys practicing continually, developing habits that allow me to become “lost” in the creative process. This does produce a gradual sophistication of my output. However I lose sight of the fact that quantum leaps in creativity, and the enjoyment thereof, are the product of learning and melding new capabilities. It is because the transition period often produces “unsuccessful” results that I naturally resist change. These quotes remind me of the shortsighted nature and long term constriction of this, more comfortable approach.

The remainder of this post refers to the photo at the top of this post. It is a highly processed image of a water fall in San Diego Botanical Gardens (previously Quail Botanical Gardens) located in Encinitas California about 15 miles north of the city of San Diego. I highly recommend it to anyone interested in nature or photography. It is roughly 50 feet (four stories) high. IMG-7272origi-Pub

This is the original, unprocessed image. Many people will like it better than my processed version. I respect that.

Processing:My intents were first to exaggerate detail and secondly to make the water more apparent by increasing its brightness.  First, minor processing was done in Adobe’s Camera Raw (added a little “clarity” and “vibrance”, reduced noise and slightly sharpened (pre-sharpening which is not destructive as is output sharpening). Then Nik Color Efex Pro 4 was used to considerably increase contrast and detail (“detail enhancer” filter). Photoshop Elements was then used to dodge (increase the brightness of) the water and burn (darken) some of the bright rocks and the sky in order to direct the eye more toward the water. Finally Nik Sharperner Pro 3 provided output sharpening for display (This is the destructive type of sharpening that should be done as the very past step of the processing).

Now, at the top of this post, it appears as I wish it would have looked to my eye at the time. I will  reprocess this image several more times in different ways/styles for comparison (and maybe be a little creativity).

I am available to assist photographers who are just beginning their experience with photo processing.

J. Michael Harroun©2013 NaturePhotoRehab.com

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Christmas Sunset Surprise

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Grace means more than gifts. In grace something is transcended, once and for all overcome. Grace happens in spite of something; it happens in spite of separateness and alienation. Grace means that life is once again united with life, self is reconciled with self. Grace means accepting the abandoned one. Grace transforms fate into a meaningful vocation. It transforms guilt to trust and courage. The word grace has something triumphant in it.  – Yrjo Kallinen

(This is my first post using my new writing style. I call it “grammar and punctuation don’t matter”. It is part of my plan to post more frequently by spending less time on each individual post. As I write this, it does not sound like a good idea to sacrifice quality for volume. However, not to be inconvenienced by logic, I am going to try it.)

On Christmas day, the sky was heavily overcast. There had been rain the night before.  I expected that there would be no visible sunset. However I also knew that some of the most spectacular sunsets occur as the sky is clearing after bad weather. An hour before sunset, the sky was clearing a little on the other side of the mountain range, about 10 miles away toward the west. Not expecting to find anything worth photographing, I went to a spot with a panoramic view of the sky and mountain range. The sun then set uneventfully (no color), hidden behind clouds.  However, five minutes after the actual setting of the sun, the overcast condition quickly broke up, and the sky became bright gold in front of me plus overhead, to the sides and behind me. Then the sky turned pink briefly and faded away. Wow! I could not capture the entire amount of sky involved. To include as much sky as possible, I took several series of images for panoramic composites.

My willingness to take the camera to what I expected to be a “no show” sunset, led to experiencing one of the top ten sunsets of my life. This caused me to think about other aspects of successful sunset photography.

  • Go often: The majority of sunsets will not be impressive.  However, if you are not there, you cannot get images of the great sunsets when they do occur. (I am still unable to predict whether a sunset will be exceptional).
  • Arrive early: Sun rays coming through clouds (traditionally called “God rays” by photographers) can be most prominent up to an hour before the sun actually sets. Plus, arriving early will allow you to scout out good locations and foreground subjects.
  • Stay late: The best color (pink and red) often occur 20 to 25 minutes after the sun sets.
  • Bring a tripod: Exposures of the last pink or red can be several seconds in duration.
  • The most dramatic sunsets occur when the weather is changing, particularly when bad weather is moving out.
  • Unless a sunset is spectacular, include a foreground object. The easiest way to do this is with the foreground object is as a silhouette. If a silhouette is not used, correct exposure for both this object and the sky simultaneously requires either a neutral density filter or bracketed exposures used for high dynamic range (HDR) processing. (HDR processing is the technique that I personally like. It is surprisingly easy. First bracket your exposure for 3 frames in increments of 1 to 2 stops. Then process them with software such as Photomatix from http://www.hdrsoft.com which offers a free trial of their software. This is a good starting point for shooting HDR, although this technique, to be mastered, is very complex.)

Image processing:

  • I processed the original RAW  format images in Photoshop Elements raw converter.
  • Brightness, vibrance and clarity were added.
  • Noise, both luminance and color, were reduced.
  • A tiny bit of sharpening was added.

Here is the result on a single frame.

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Although improved via raw converter processing, the images (like the single frame above), the color is a little dull and the lighting a little flat. Therefore, after generating a panorama using Photoshop Elements panorama tool, I used Nik ColorEfx Pro4 (once again, to the rescue). I used a little Pro Constrast and a little Color Range Contrast with good results.

Finally, I sharpened via Nik Sharpener Pro 3.0 (which I love). The final composite is the image at the top of this post. It is made from 7 images taken from side to side with the camera in a vertical orientation and a one third overlap between frames.

I welcome comments, criticism and suggestions for future blog topics.

 

I am available at my photo enhancement website (NaturePhotoRehab.com) to assist clients with transforming their common nature photos into uncommon works of art that they are proud to give as gifts or to hang on their own wall for inspiration.

J. Michael Harroun ©2013  NaturePhotoRehab.com

Digital Photography: the ISO setting

“The truth is that our finest moments are most likely to occur when we are feeling deeply uncomfortable, unhappy, or unfulfilled. For it is only in such moments, propelled by our discomfort, that we are likely to step out of our ruts and start searching for different ways or truer answers.”  -M. Scott Peck

 

The level of difficulty for this discussion of ISO settings: beginners

Understanding ISO is surprisingly easy.

  • Sensor sensitivity to light: ISO is a carryover from the days of film photography. It referred to the amount of sensitivity to light of a particular type of film. Similarly in digital photography, ISO indicates the degree of sensitivity to light of the camera’s light sensor. This sensitivity is adjustable. The higher the ISO, the more sensitive is the sensor to light. This greater sensitivity of the sensor allows the use of a faster the shutter speed and/or smaller aperture diameter than would be needed if the ISO (and sensitivity to light) were lower. A faster shutter speed is usually an advantage because it increases the probability that the image will be sharp.
  • Electronic noise: The disadvantage of high ISO however, is that more sensitive pixels are more likely to be activated by electron movement within the sensor itself, rather than by the light. This accidental firing of pixels produces red and green pixel-sized dots (color noise) and mottling in areas of uniform lighting such as blue sky (luminance noise). In addition to ISO, the amount of noise within an image depends upon the sensor type and quality.Color noise (also called chrominance noise and chromatic aberration) shows up most readily in the darker areas of your photo when viewed at a magnification of 150% or higher (200% makes this easier for me). Luminance noise (also called contrast noise) areas of uniform color and lighting, such as blue sky, when viewed at a magnification of 150% or higher (again, 200% is easiest for me).
  • Which ISO is best? To minimize the amount of electronic noise in your images, use the lowest ISO setting that allows you a shutter speed fast enough to achieve the effect that you want for that image. Usually, the preferable effect is sharpness. For instance, to “freeze” the motion of a person walking, a shutter speed of at least 1/125 sec is needed. To stop the motion of a person running, a minimum shutter speed of 1/250 sec is needed. In order to have sharp images of sporting activities often requires a shutter speed of at least 1/500 sec. If the light on the scene is low, shutter speeds this fast will not be possible with a low ISO setting, even when using a large diameter aperture.  When in this situation, increase the ISO only as much as is needed to achieve your desired shutter speed.   This increased noise level just needs to be tolerated or, better yet, removed with editing software. A high ISO is also necessary in very low light situations such as night photography, especially night sky photography of the stars.
  • When slow shutter speed is needed, a low ISO is helpful: Sometimes a blur is the photographer’s desired effect. The most common example is flowing water or waves that one wants to appear smooth or hazy. In this case a long shutter speed is needed, typically 2 to 15 seconds. Using the lowest ISO setting (and a small diameter aperture like f/16 or f/22) will help to get shutter speeds that last this long without overexposing your image. Another example of a specific need for a low ISO setting is when the desired effect is a blurring of a person walking or of moving automobiles, in order to convey the feeling of speed.
  • For those people who do not want to mess with ISO settings, use your camera’s program option for landscape, portrait, close up, action/sports and night photography. Your camera will then automatically provide you with the ISO setting which is usually the best.

Condensed version for those in a hurry:

  • The higher the ISO number, the more sensitive the camera’s sensor is to light.
  • The higher the sensor’s sensitivity to light, the more electronic “noise” the image contains.
  • To minimize the amount of noise, use the lowest ISO number that allows a fast enough shutter speed to achieve the effect that you want (usually sharpness).
  • Cameras with program options such as landscape, portrait, close up, action/sports and night photography, will automatically provide you with the ISO setting which is usually the best for that purpose.
  • Electronic noise can be removed with editing software. However bold noise removal creates loss of sharpness or decreased saturation of color.

When noise in an image usually does not matter: When your photo is going to be displayed on the web or you will make prints no larger than 4 inches by 6 inches, noise will usually not be apparent unless the noise level is very high. (But you never know when you will shoot a remarkable image that you wish to enlarge and print. A high noise level will require special processing for removal).

Noise removal

  • Every digital image contains noise regardless of the ISO or quality of the camera.
  • Noise removal is the first step of image processing by professionals.
  • High ISO creates much more noise than usual, making its reduction even more important. Noise removal is accomplished with editing software (luminance noise reduction and color noise reduction) such as the software that came with your camera, Photoshop, Photoshop Elements, Lightroom and many other editing programs. (The best, and easiest to use noise reduction software that I know of is Nik software’s Dfine program). However large amounts of noise reduction produce slightly blurred images from luminance noise reduction and/or unsaturated (faded) color from color noise reduction. A slightly blurry image can sometimes be saved by applying extra sharpening with your editing software. Desaturated color can be easily fixed by adding a little saturation with editing software.

I welcome comments, criticisms and questions about specific photography issues that you may be experiencing.

I am available at NaturePhotoRehab.com where I help people have their images transformed into impressive works of art that they are proud to either hang on their own wall or give as a gift.

J. Michael Harroun©2012 NaturePhotoRehab.com

Digital Photography: Processing Is Not Cheating

“The important thing is this: to be ready at any moment to sacrifice what you are for what you could become.”   – Charles Dickens

Level of difficulty: beginners

Is image processing cheating? No.

  • Digital images are the result of processing the data generated from millions of red, blue and green pixels in the light sensor. Processing is actually a necessity in order for a digital photo to look realistic. Of course, processing can also be use to create an emotional response in the viewer such as ephemeral, moody, dramatic or old fashioned.
  • Over-processing produces a garish and unnatural appearance causing the viewer to ask “Is that what it really looked like?
  • Correct processing causes the viewer to say “Wow”.
  • Over 99% of all professional’s digital images are processed.

What is image processing?

  • the adjustment/manipulation of the data generated by the digital sensor when it is exposed to light. Some frequently adjusted properites of an image are contrast, color hue, saturation, brightness of highlights, darkness of shadows, white balance, sharpness, etc).
  • Processing is done in-camera immediately after the photo is taken to create jpg images.
  • If you do not direct the adjustments, you will have to accept a lot of guess work by your camera and its image editing software.

There are three main categories of image processing: in camera, raw converter and “post processing”. I will primarily address in-camera and raw converter processing today. Post-processing with full editing software, such as Photoshop will be covered in a future post.

In camera processing:  Within all digital cameras, there is a tiny computer processor. Unless a camera is set to record a “camera raw” file format, this processor modifies/adjusts the data generated by the digital sensor immediately after a photo is taken. If you are recording images in the jpg file format (image file name ends in .jpg), then you are using processed images. Your images are being processed within your camera. This processing is required to create a jpg file format image. If you do not adjust the camera’s default settings for creating a jpg image, then your camera has to make a lot of guesses about the lighting conditions present and about how you want your image to look. If you like the appearance of all your jpg photos already, then there is no reason to make any change. However, if some of your images look dull, flat or washed-out, then you will benefit from learning how to control at least some of your camera’s processing. It’s not as difficult as it sounds.  In fact the first stage is very easy.

How do I begin processing without being overwhelmed? Do just a little at a time. If possible, take at least 20 minutes every day or two to learn something new about the editing programs that you have (an editing program comes with every digital camera). Then take at least 10 minutes to experiment with one of your images with the information that you learned.

How to begin controlling the in-camera processing?

1) For in-camera processing of jpg images, begin using you camera’s program modes for landscape, portrait, night scenes, etc (Different manufacturers give these different names, but common names are picture styles or creative program modes). They are usually accessed either via a button on the back of the camera or with a wheel that has tiny pictures on it). These will allow you to use presets that your camera came with, so that you do not need to make all the changes by yourself initially.

  • “Standard” (auto) programs are for general use. They usually increase contrast mildly and color vividness (saturation) and sharpness moderately.
  • The landscape setting (usually with a picture of a mountain) will make blues (sky) and greens (grass and tree leaves) more vivid (more saturated), strongly increase sharpness for greater detail and use a small aperture width for maximal depth of focus.
  • Portrait mode will adjust color for better skin tones, add  little or no sharpness (for smooth skin) and use a medium width aperture so that the background is blurred (helping to keep one’s attention on the person).
  • Close up mode (usually with a picture of a flower) increases color saturation, increases sharpness and uses a wide aperture for fast shutter speed and blurring of foreground and background.
  • Other specific program modes or picture styles, such as night scenes or action/sports, make their own distinctive adjustments. Letting your camera know what type of picture you are taking, will help it to produce a more pleasing image.

2)  The reason to take greater control over the in-camera processing is to decrease the amount of guess work that your camera has to do about the style, composition and lighting of the image that you took. Also your camera will not have to guess about your personal preferences for your images (For instance, I like more contrast, saturation and sharpness than average). The goal is to create more realistic or evocative images, although it will allow you to have unusual or weird effects if you choose. Generally we want images that appear realistic to the viewer.

  • White balance: First, I recommend that you learn to set the white balance. I covered this in detail in my last post entitled “Photography: White Balance Essentials”. If you are not familiar with white balance, please check it out.
  • Contrast, saturation and sharpness: Find your camera’s settings for these image characteristics.  Usually they will be in the recording menu or the menu for “functions” or custom picture styles. (Often there is a button on the back of the camera that gets you quickly to these settings.  (Check your camera’s instruction manual).There, you can individually adjust contrast, color saturation, sharpness, color tone and perhaps some additional properties (depending upon your particular camera).  Begin by adjusting just one of these characteristics at a time. (The changes that you will make now will not affect your camera’s settings for the preset picture styles and creative program modes (landscape, portrait, close up, etc that I mentioned with in-camera processing-part 1, above).
  • Setting contrast: Low contrast gives a smooth, delicate, dreamy or flat appearance. High contrast increases depth of field, detail and texture. It also can give a more dramatic appearance to images. Take pictures of the same thing with different settings for contrast. Start with the lowest amount of contrast offered and work up to the maximal setting. Compare the images to see which you like best.  Make a note of it. (The very highest and lowest settings are likely to make it look weird, but sometimes you may want to make your images weird). You probably will like a different amount of contrast for landscapes than for portraits, than for night scenes, etc. You can add that information later. It’s a very good idea to keep a record or journal of the settings that you like. (In the past, whenever I have not written it down immediately, I have forgotten the result and have to do it all again.)
  • Saturation (vividness of colors):  Low saturation tends to give calm, delicate of dreamy feel to the images. Moderate saturation gives vivid colors and a dramatic feeling. High saturation tends to look garish and definitely unnatural. Take a photo of something at each of the settings offered by your camera from the lowest to highest option. Again compare the pictures to see which settings you like best for this particular type of photo and write it down. You can do this with other types of photos later to see whether you like different t settings for them.
  • Sharpening: Generally, low sharpening gives a smooth look to skin in portraits, less apparent texture and depth of field and helps with a calm or delicate feel. High amounts of sharpening bring out texture and depth of field. It is often used for landscapes or images with lots of detail (like leaves of a tree). But high levels of sharpening will ruin most images, so be judicious. High levels of sharpening create lots of artifacts (tiny circles called halos at the edges of things). Halo artifacts give a very unnatural appearance and cannot be removed once a jpg image is recorded. A very common error is to apply too much sharpening.

Images recorded in a jpg file format loose data each time they are opened. However images with a tiff file format are stable and do not loose information. It’s best to convert your jpg images to tiff images as soon as they are into your computer. (If you click on the “File” menu  and click “Save as”, you can change the file format to end with the letters .tiff. )

Raw converter processing is primarily for images recorded with a “camera raw” file format (CR2 for Canon, NEF for Nikon and other manufacturers have their own initials for this type of file). “Raw files” contain only the unprocessed data collected from the sensor when it was exposed to light (It is no more complicated than that). The advantage of using raw files are that they are durable. They do not loose information with repeated opening. Any editing changes applied to a raw file can be erased or replaced at any time. The adjustments do not alter the original image file. In this way, raw files are analogous to negatives in the film days of old.

  • All cameras that offer the option of a raw file format come with the software to edit those images (technically called a raw converter). Other programs, such as Photoshop and Photoshop Elements also contain raw converters.
  • Keeping with my recommendation that processing be learned a little at a time, start with adjusting two image characteristics: white balance and sharpness.
  • White balance: Even if you set the white balance prior to taking your photo, the color may not look just right to you when it is opened in the raw converter software. (It’s easiest to fix color if something in your photo is , or at least is supposed to be,  pure white. Find the drop down menu for white balance (usually toward the top of the screen or toolbar) and click on each option successively (sunny, shade, cloudy, etc) to see which gives the correct color. If none of these options gives a good resut, look for the eyedropper (white balance) tool and click on something that is supposed to be white. You may need to click on a couple of different places on the white object to get the best result. If nothing in your image is white, most programs allow you to click on something that is supposed to be neutral gray to determine white balance (It does not have to actually be neutral gray, just something that is supoosed to look newtral gray.
  • Sharpening: All raw images, require some sharpening to look good. This type of sharpening is safe for your image. For good results, try just a small amount of sharpening. If your program offers you a sharpening scale from neg 4 to +4, try +1 or +2. Check your image on the screen at 100% magnification to see if you like the result. If using Photoshop Elements raw converter, get to sharpening by clicking on the little tab with the triangle on it (just above white balance adjustmejnt). Then try amount 25 to 40, radius 1 and detail 25 (for images with lots of detail, like landscapes, movethe  detail slider up to 50). You do not need to do all the sharpening now. More sharpening is usually added later, after further  editing with a full feature program such as Photoshop, Photoshop Elements or Lightroom.  That type of sharpening is destructive and needs to be done as the very last step of processing.
  • Gradually add additional settings after becoming comfortable with these two settings. Adding a little at a time, but frequently is the a great way to learn processing.

Post-processing with full edit software will be covered in a future post.

Comments, suggestions (and criticisms) are welcome.

I am available at NaturePhotoRehab.com where I help people transform their nature images into impressive works of art that they are proud to give as a gift or to hang on their own wall for inspiration. I offer photo retouching, complex processing and enhancements, enlargements, prints (up to 12in x 18in) and framing.

2012©J. Michael Harroun  NaturePhotoRehab.com

 

Digital Photography: Optimum Exposure

“I’ve missed more than 9,000 shots in my career. I’ve lost almost 300 games. 26 times I’ve been trusted to take the game winning shot and missed. I’ve failed over and over and over again in my life and that is why I succeed.”  – Michael Jordan

For many years, Michael Jordan was, by far, the world’s best basketball player. He was capable of phenomenal physical maneuvers and accuracy previously thought to be impossible. That is why I find this quote so impressive, both for its humility and for its wisdom.

My last post was about thoughts and feelings. This post focuses on technique. Specifically, it explains how to get the best detail in the low light and shadow areas, and another adjustment for maximizing color detail in the highlights of your photos.

Digital sensor limitation: In a digital camera, the actual picture is taken by a sensor which is made of millions of pixels. It is these pixels that actually “see” the light. When bright light is falling on a pixel, much more information about the light is recorded than when it is being exposed to low light. As a result, hundreds of times more gradations of light are recorded from the bright areas of a digital photo than from the low light areas. As a result, shadows show relatively little detail.

Correcting for limited detail in darker areas:  There are two stages to the correction. First, slightly overexpose your initial image. Second, use your editing software to decrease the exposure an equal amount (if it appears too bright). You end up with an image correctly exposed, but with more detail in the low light areas and shadows.

A drawback to this overexposure technique is that gradations of color will be lost in the highlights, resulting in a blotchy appearance of very bright areas of color. If your primary interest is fine detail in color, please skip down to “Optimum exposure for color”.

Correction Stage 1: Controlled overexposure is the key. But how much overexposure is appropriate? (If there is too much overexposure, detail in the highlights will be lost or “blown out”). The precise amount of overexposure is determined by using the histogram (The dreaded histogram… but wait, don’t go. This is not terribly difficult).

A histogram is simply a graphic representation of the light that the sensor is “seeing”.  The histogram looks like a mountain range. The right side of the mountain range represents the brightest areas of your photo. The higher the peaks, the greater the number of pixels sensing bright light. (“The right is the bright”). Conversely, the left side represents the dark areas and shadows in the photo. The higher the peaks on this left side, the greater the numbers of pixels exposed to low light. (Since this histogram is representing light intensity, it is called a luminance histogram.)

How to display the histogram: All DSLR’s (of which I am aware) provide a histogram. Many, but not all, other types of digital cameras offer this feature (Check your camera’s operation’s manual). Most cameras display the histogram only in the playback mode. To have the histogram display, first go to the playback menu. Find histogram. Set it to on (If you have a choice between luminance and color histogram, choose luminance).  Now, playback any image so that it shows on the screen. If the histogram does not show on your screen, use the display options button (located on the camera back, usually near the screen and labeled “disp”) to cycle through the display options until the histogram shows . (If you have an option for a histogram display in your pre-shot viewfinder or “live view” screen, it can usually be turned on in the recording menu. You can make your adjustments directly without using the playback mode).

Determining correct overexposure: (For most lighting conditions, exposure compensaton is going to be +1/3 to +2/3 stops). We will be moving the mountain peaks of your histogram toward the right, approaching the far right end of the baseline, without going so far that any of them abruptly disappear.

  • Turn on automatic playback so that your image shows on the screen immediately after your shot is taken.
  • With exposure compensation set to zero, take a photo in your usual manner.
  • In playback mode, check the histogram for your image.
  • If the peaks on the right end of your histogram do not extend almost completely to the far right side of the baseline, then set exposure compensation up by +1/3 to +1/2 stop.
  • Repeat the same shot. Again check the histogram.
  • The peaks will extend somewhat more to the right (If they extend almost to the far right end of the baseline, then you are done with this stage). If there is still a lot of black space between your peaks and the far right baseline, set exposure compensation up another +1/3 to +1/2 stop.
  • Repeat the shot and check histogram again.  (Probably you are done now, but repeat if needed).
  • For most lighting conditions, in my experience, an exposure compensation adjustment of +2/3 stop is correct.
  • Here are two tips for remembering  this technique.  First, “The bright is on the right”. Second, “Moving (the histogram) to the right” is abbreviated Mttr, pronounced “Meter” as in light meter)
  • The above technique gives you correct exposure for that specific subject and lighting condition. Whenever lighting conditions change, check your histogram and, again, adjust exposure compensation with this technique.
  • A word of warning: Do not set it and forget it. Re-evaluate exposure for every new lighting condition.

Correction Stage 2: This is done with your editing software. Any editing program will work for this. It does not need to be elaborate (The program that came with your camera will work fine). Open the image that you just overexposed (If you like the way it looks, you can skip this stage).  If you image appears too bright, slide the exposure slider to the left to decrease exposure by the same amount that you increased it when taking your photo. (While you have your editing program open, you may wish to adjust white balance, contrast or any other parameter that improves the appearance your image)

Results: Now you have an image with correct exposure, but with more detail in the darker areas and shadows than it would have had.

Optimum exposure for color: A drawback of the above (luminance) overexposure technique is that fine gradations of color will be lost in the highlights, resulting in a blotchy appearance of the color in these areas.  For best detail in color highlights, an image usually needs to be underexposed a small amount. To determine the appropriate amount underexposure, use the color histogram, not the luminance histogram.  (If your camera does not offer a color histogram, I recommend “guesstimating” with exposure compensation of -1/3 in subdued lighting and of -2/3 in brightly lit conditions). Color histogram display during playback is usually set in the same way that the luminance histogram was set above (Set it in the playback menu and also with the display options button on the back of the camera).

  • Take a shot with exposure compensation zero. Check the color histogram.
  • Probably at least one color will extend all the way to the far right end of the baseline and abruptly cut off (No black area between the tips or all the colors and the far right baseline).  If that is what you see, decrease exposure compensation by 1/3 to 1/2 stop. (If the color channels approach, but do not abruptly disappear off the far right side of the baseline, then your exposure (for color) is correct already.
  • Repeat your same shot and again check the histogram.
  • If any color channel still abruptly cuts off at the far right, decease exposure compensation another 1/3 to 1/2 stop.
  • Probably you have good results by now, but repeat this procedure once more if needed.
  • Generally the correct amount of underexposure will be -1/2 to -2/3 stop.
  • Your color highlights will now be the best that your camera can offer.
  • However, whenever lighting conditions change, re-evaluate the histogram and adjust exposure compensation if needed.
  • A word of warning: Do not set it and forget it. Re-evaluate exposure for every new lighting condition.

I welcome comments, corrections and suggestions for future blog topics.

I am available at NaturePhotoRehab.com to assist clients with transforming their images into impressive works of art that they will be proud to either hang on their own wall or to give as a gift.

J. Michael Harroun(c)2012  NaturePhotoRehab.com

Expanded depth of focus: Trouble Shooting

sml purp pr c grn (c)“Let the beauty we love become the good we do.”  -Rumi

This is the second in a series of blogs about the photographic technique called expanded depth of focus. For this, multiple digital photos are  taken of the same subject, all identical expect for the area of sharp focus. Then, by computer processing,all the different areas of crisp focus are combined into a single image which is entirely in focus. This allows images to appear more life-like. It is one of the marvals of digital photography that cannot be duplicated with film images.

If you are unfamiliar with this photographic technique, but somewhat interested, please check out my blog post from July 16, which is an introduction to the topic. If you are knowledgeable about this topic, but have no interest in trouble shooting yet, please go to my next post entitled “Philosophy”.

Now I will address the individual who has tried this photographic technique  unsuccessfully. I am referring to those who are saying, “I did everything right, so what went wrong?”  

Being aware: Fully 95% of my unusable series are due to an error of mine that I did not recognize at the time. I overlooked a problem that, if recognized, could have been corrected at the time it occurred. I know this, because as I get more experience and become more aware, I get a much greater percentage of excellent results.

I will be assuming that you used the proper equipment and technique as briefly noted in my post of July 19 (Table of Contents). Some, not all, of my assumptions are that you:

  • used a camera with enough megapixels and file size and file format to give sharp focus for the amount of enlargement required for your computer screen and your planned print size.
  • utilized a lossless file format. Raw images are best.
  • used a focusing rail
  • used mirror lock-up mode for DSLR’s
  • used a shutter release cord or remote control if mirror lock-up is needed
  • used small enough increments between focal planes that the areas of sharp focus overlap. This is critically important, because areas of focus must overlap. Thus the increment of advancement of the focusing rail between frames would be, at most, 1/3 of the lens’s depth for that distance from the subject. Specificly, if a  macro lens is 10 inches from the subject, the depth of sharp focus may be only 3 millimeters (about 1/8 inch) deep. Therefore the increment of advancement of the focusing rail will need to be no greater than 1 millimeter (1/24 inch). However when 3 feet from the subject, this same lens may exhibit a depth of field of 48 mm (2 inches). In this case the correct increment would be, at most, 16mm (0.7 in). To determine your lens’s characterist, take an image of a ruler end on. Take images at the lens’s closest focal distance, then double the distance and double it again. The measurements do not need to be precise. On your computer, evaluate how many sixteenths of an inch are in crisp focus. one third of that distance is the largerst increment between frames that will give good results.
  • been meticulous to avoid any movement of the subject by air movement or change in the shape of the flower due to heat change.
  • used editing software that allowed you to compare and confirm focus and location precisely among frames
  • used sophisticated software for generating your composite
  • were knowledgeable and adept in the use of your software

  Trouble shooting is an expansive topic. Here I will cover only some of the more sneaky problems.

 Tripod

  • Tripod feet can settle into soft ground or leaves, changing the camera position.
  • If tripod was bumped, it may not have returned exactly to its original position.
  • If all of the tripod leg locks/collars was not fully tightened. A leg can shorten, changing the camera position.
  • If the tripod legs were not splayed all the way to their stop, they can spread causing a change in camera position. This is most often a problem when shooting from a low enough angle that the legs needed to be spread wider than usual.If your camera position is low enough to the ground, the center post can touch the ground, allowing the tripod to  rock.

 Camera

If the camera is not fully tightened to the focusing rail, it can slightly twist/torque. This is most likely when shooting in a vertical orientation. That happened to me this morning. I noticed & corrected before any harm had occurred.

Tripod head and focusing rail.

Similarly, if either of these is not firmly secured, they can twist/torque, shifting the position of the camera

Aperture

If the aperture was more than 1 stop away from f/8, the sharpness will be less than the camera /lens is capable of producing. For most lenses, f/8 usually provides the best combination of sharpness & depth of focus. I know that landscape depth of field is considered best at f/16 or a smaller diameter. This does not apply here. I will go into detail about this in 2-3 more blogs from now entitled “Aperture”.

Exposure problems

1) Viewfinder of a DSLR camera, if not covered/capped, will let in light that changes the exposure. This is particularly a problem when direct sunlight falls on the viewfinder.

2) Focusing rail, if not locked with fine/precise lock at each incremental focal distance will change subject location too much. Additionally, if focusing rail was not firmly tightened onto the tripod head, it can twist causing movement of the subject

3)Soft, unsharp images

  • File size too small. In the shooting menu, set file size to the biggest numbers that is offered.
  • Too little data or date loss. This is a problem with jpg images. Shooting in RAW format is recommended for many reasons.
  • Stray light: There may have been bright light impinging upon the lens at a sharp angle.  A lens hood prevents most of this. Check with the company that made your lens for the specific one to use. Some cannot be used for macro work because they cast a shadow upon your subject. A polarizing filter is highly recommended when shooting outdoors and when shooting shiny, wet or alive objects indoors. Besides enhancing colors and decreasing reflections, it usually blocks stray light and can take the place of a lens hood. However, I shoot outdoors with reflectors producing very bright light impinging upon the surface of the polarizing filter from multiple directions. For these conditions, I think that a lens hood and a polarizing filter give the best results. Besides enhancing colors and decreasing reflections, it often can take the place of a lens hood. However, I shoot outdoors with reflectors producing  bright light coming from many directions. I find that a lens hood and a polarizing filter seem to give the best results.

 Lens

  •  Lens distortion is particularly a problem when your subject enlarged or “bloomed” out near the edge of the frame.  That presents bizarre data from this area to your stacking software. However, the central portion of the frames will probably give good results. Some editing software can remove lens distortion. I have experience only with Canon’s Digital Photo Professional software. It will remove the distortion of some Canon lenses, but it’s time consuming and this does not guarantee that it will give good stacking results.
  • Focusing ring/collar was touched when reaching for the camera or focusing rail. This can happen even when there’s no noticeable movement of the focusing collar. I have to be careful about this because I steady the camera with my left hand while changing the position of the focusing rail with my right hand.

Subject moved

  • Change of support structure: If a flower is getting even the slightest support from one of its petals or leaves (or a petal, leaf or stem of an adjacent flower) any subtle change of its shape can allow a shift in your subject’s position.  This is more likely if there is an intermittent breeze or if I potted plant has recently been moved.
  • Similarly, if a petal, leaf or stem of your subject flower is in contact with petal, leaf or stem of an adjacent flower, then any movement from a breeze can move your subject flower. If there are lots of leaves touching, movement of any portion of the plant can move your subject. To prevent this, wait until there is no movement of any part of the entire plant before shooting. The more complex the interactions among the plant parts and the stronger the wind, the more likely it is that your subject will not return fully to its original position. Although this is true, I shoot outdoors all the time and find this problem to be rare unless the intermittent wind is quite strong.
  • Flowers frequently change shape during a shoot if they were freshly cut or if they were recently moved from shade to direct sun or vice versa. I find this less of a problem if a cut flower has only the bottom ½ inch of the stem in the water.

Because there are so many possible problems, I recommend shooting two series of everything when beginning to get experience with this technique. Start the set up for the second series of images from the very beginning, just as though it was the first series.

I hope this has been useful information for someone. You are welcome to ask me about particular issues that you would like help with.

If anyone would like assistance with processing of their photos, please check out my web site at NaturePhotoRehab.com

Expanded depth of focus photography: “Table of Contents”

Lg purp pr shp (c)“Great things are done by a series of small things brought together.”   Vincent van Gogh

This is my second blog post regarding the expanded depth of field/focus photographic technique. If you are unfamiliar with this technique, please check out my post from July 16, 2012 entitled Expanded depth of field / focus stacking: Introduction. This current installment is an brief overview of the subject, essentially providing a “Table of Contents” for the remainder of this series.

Experience is the best teacher.  Don’t expect to achieve your signature magazine cover shot on the first day. (Although it could happen)

Attitude: If I’m irritable or angry, I usually made mistakes that worsen my mood. Some days it’s better to just do the laundry.

Mountain climber’s state of mind:  I try to maintain an attitude that I call the mountain climber’s state of mind. A mountain or rock climber might make one or two thousand decisions regarding placement of the hands and feet and shifts of weight during a climb. It takes only one mistake out of the thousands to produce a slip, a slide or even a fall that can ruin that entire climbing experience. Similarly, it takes only one mistake out of hundreds of decisions to render a set of images unusable for a successful composite.  Remembering the mountain climber causes me to work very deliberately, move a little slower than usual and maintain awareness of the moment. This produces far fewer mistakes and many more inspiring results than I used to get. Luckily, however, few people have sustained serious injury as a result of a mistake while shooting images for expanded depth of field processing.

Being thorough: The goal is not to create some tack sharp images. The goal is to get at least one entire, coordinated series of tack sharp images with minimal change of position on the sensor. If a few are blurry and unusable, it could render the whole set useless. By remaining aware, mistakes or even possible mistakes can be recognized when they occur. Then the potentially bad image can be deleted and re-shot.

1. Equipment:

  • Camera with manual focus and manual exposure. If your camera has a movable mirror, it’s essential that you have & use the mirror lock-up option. Apart from these details, your camera does not need to be particularly sophisticated.
  • Sturdy tripod with feet on a solid surface
  • Focusing rail: This is essential for close up & macro.
  • Cable shutter release (or remote): This is essential
  • Loupe for screen is useful for outdoor work, but not essential. Hoodman brand has a good one, but expensive.
  • Cover/cap for viewfinder unless your viewfinder is actually a tiny video display.
  • Battery(s) fully charged
  • Memory card(s) with plenty of capacity for data

2. Frame your subject in the viewfinder or screen knowing that it will become larger on your sensor at the deeper focal planes than at the initial, close focal planes. This is called “blooming”.

3. Initial focus is crucial. I use a card held immediately in front of the closest point of focus. I use auto focus limited to only the center focusing point and immediately switch the lens back to manual focus. My eyes are not good enough to achieve good focus directly through the viewfinder or on the screen, even when the camera presents a magnified image. For this technique to succeed, your camera/lens combination must be exact and precise consistently. However, people with eyes better than mine can get good results obtaining initial focus entirely via manual focus.

4. Exposure: use manual exposure. Use the aperture that gives the best combination of sharp and depth of field, f/8 for most lenses.

5. Check viewfinder or screen again for subject placement & focus

6. Begin shooting, but remain alert. Whenever I get into a mechanical mode of thinking ( move the rail & shoot ,then move the rail & shoot, then move the rail & shoot), I usually miss something important and end up with a useless batch of images

7. Move focusing rail in equal and very small increments if you want detail in things as small as spines, hairs or pollen. It’s necessary for the areas in focus to overlap between images to get good results. The depth of focus of any one frame depends on your specific lens and its distance from the subject. However it’s not unusual to have just a couple of millimeters, perhaps 1/16 of an inch in crisp focus in any one frame. I usually use increments of 1-4 mm (1/32 – 1/8 inch). The closer the subject is to your lens, the smaller the increment needs to be. Begin at closest point of your subject and move the focal plane gradually toward the deepest part of it. Another advantage is that the smaller increments of change of focal plane between images, the better the chance that you can have a couple of flawed images that you can throw out and still have a successful composite in the end.

8. Lock the focusing rail at each new location to prevent rail sag during extension.

9. Processing

  • Edit
  • RAW processing
  • Converting to tiff
  • Software: I love Helicon Focus 5.2. Its available at HeliconSoft.com. However I understand there are other good programs available. 
  • Review, retouch

10. ENJOY. You’ve accomplished something that was impossible up until about 10 years ago.

I hope that this will be a help to someone. I welcome comments and criticism.

Through my website at NaturePhotoRehab.com I assist people to transform their photos into impressive works of art that they are proud to give as gifts or to hamg them on their own wall. I provide photo retouching, complex processing and enhancements, prints, enlargements and framing.

©J. Michael Harroun 2012