Light, Lines & Color

H is for Histogram

The word histogram strikes fear in the hearts of many a photographer - beginner and seasoned alike. It's that graph that you can see on the LCD screen on the back of your camera that looks painfully like those you saw in the statistics class that you nearly failed. I'm here to dispel the paralysis you feel just thinking about it. The histogram is your friend.

Let me over simplify an explanation so that you can begin to use it as the tool it really is. Here are 10 things to help you understand and use a histogram.

1. A histogram is a graph that shows the tones within a photograph, with dark/black being on the left and bright/white being on the right.
2. The height of any point on the graph indicates the amount of pixels at any particular level of darkness or brightness.
3. Just like in football "clipping" is bad, in this case clipped pixels.
4. When a histogram shows pixels climbing either end of the graph, they are clipped which means:
   • details in those tones are lost,
   • the appearance of the image will most likely be degraded, and
   • the photograph is incorrectly exposed
5. "Expose to the right." There is more data in bright pixels than dark ones, so a graph favoring the righthand side is a good thing.
6. Clipping or blowing out highlights (brights) is a sin in digital photography, so expose an image to the right but NOT the far right. 
7. If there's a line climbing the right hand side of the graph looking like it's heading for the stars, the highlights are blown - the data is gone. What can a photographer do?
8. Adjust the exposure in camera. Reduce the brightness in an image by stopping down - move the Exposure Compensation (+/-) in the negative direction until clipping is no longer a major issue. As you move the EV, the histogram will move left.
9. Avoid clipped shadows as well. There is less data in "dark" pixels; if you expose to the right you'll avoid ugly noise in the shadows.
10. Histograms can be really handy when you're shooting in bright light and can't see the image in the LCD screen; it enables you to reach every photographer's goal - a well exposed photograph in-camera.

 

 

G is for Gear

I cannot tell you how many articles I have read on the subject of gear - many advocating the importance of gear (usually sponsored by someone who can benefit from taking that position) and many saying that gear isn't important that it's the photographer's use of the gear he/she has. I happen to fall in to the latter camp. Beautiful, even award-winning, images can be made with low-end DSLRs, point-and-shoots, and even handheld devices like iPads and iPhones. In my opinion, what needs to come first before expensive equipment and gear, is a good working-knowledge of the gear you do have and an understanding of light, lines and color, and how to capture them.

Taken January 2013 with Nikon D60 200mm
Shutter Priority 1/2000 second at f/6.3 on ISO 400

Three and a half years ago I was "downsized" from my job at a Wall Street bank, and thus began my journey deep into photography. My husband joined the digital revolution in the late 1990s and I succumbed in 2008 with the purchase of my first digital single lens reflex camera (DSLR). It was a Nikon D60 kit that included a wide angle (18-55mm) and a telephoto (55-200mm) lens and cost me around $630 which I thought was a fortune at the time. 

Taken December 2010 with Nikon D60 55mm
Aperture Priority 1/8 second at f/7.1 on ISO 400 with tripod 

In the four plus years since that purchase, I have taken an average of 8,000 pictures every year. I have read and re-read the camera's manual returning whenever I wanted to refine an image - learning more and more about the features that could help me achieve the results I wanted.

Taken September 2008 with Nikon D60 55mm
Aperture Priority 1/60 second at f/5.6 on ISO 200  

At first I used mostly automatic settings like Landscape, Sports and Close-up, then I graduated to semi-automatic settings like A (Aperture) and S (Shutter Speed), and last year I began shooting in Manual Mode. Originally I shot on default settings like automatic white balance and matrix metering whereas today I will make choices about these things. I never looked at the images I made in the LCD screen let alone at the histogram, both of which I do regularly these days. If this all sounds very daunting - it isn't. I learned all of this on the "amateur" gear I had, simply by shooting nearly every day and learning what I needed when I needed it. It was "on-the-job-training" - the kind that stays with you. 

F is for F Stop

I remember when I didn't know the difference between an F stop and a bus stop, and I was sure I was never going to "get it". Then one day I no longer thought about learning it, I simply knew it. I promise this can and will happen to you too.

In the first few weeks of this year, we've touched upon Aperture in nearly every post. It's one of the basic trio of tools (a.k.a. the triumvirate) used to create an image and it happens to be measured in these funny things called f-stops. Now I could try to explain exactly what an "f-stop" is but trust me after reading and re-reading technical explanations - I would fail. If you have a penchant for the technical by all means google f-stop and you'll find lots of definitions, all of which go over my head. I mention this because this means, you can use Aperture and its f-stops without knowing exactly what they are. Just recall from our A-post - A is for Aperture:

Aperture is measured in something called f-stops:

• a small f-stop number means a large opening,
• a large f-stop number means a small opening, and 
• changing from one f-stop to the next will either halve or double the amount of light entering the camera.

Schematic borrowed from Wikipedia

Also recall that a high f number like f/22 will give you greater depth of field than a small f number like f/5.6, i.e.more of the f/22 image will appear in focus than in the f/5.6 image. See:

Nikon D90: 1/60 second at f/22

 

Nikon D90: 1/125 second at f/5.6

Got it? Once you do you'll be well on your way to making the photographs you imagine in your mind's eye. 

E is for Exposure

Exposure - Photography is all about exposure to light and our tools to create an exposure that matches the image in our mind's eye are the triumvirate: Aperture, Shutter Speed and ISO. Let me focus first on Aperture and Shutter Speed.

I never shoot in the fully automatic setting available on my Nikon D90, rather I select Aperture or Shutter Speed depending on what I'm shooting. If I'm shooting a landscape or something static I will select aperture and then begin the thought process of how I want the image to look. If the background is messy I might want a shallow depth of field to throw the mess into a colorful blur so I'd select a low f stop number, or I may want as much of the image in focus as possible as it may all contribute to the story in the image so to maximize the depth of field I'd select a high f stop number.

Let me give a simple example of an image that is the same exposure but with differing results. For ease of demonstration, all of theses photos were taken on Aperture Priority with an ISO of 200. The only setting I changed was the Aperture; the camera adjusted the shutter speed accordingly to achieve a good exposure. Can you see the difference in the depth of field?

1/30 second at f/22 
Notice the blur of the moving palm fronds but the detail in the background. You can see the ocean especially in comparison to the last image below.

1/60 second at f/16

1/125 second at f/11

1/250 second at f/8.0

1/500 second at f/5.6
Notice the soft background resulting from the shallow depth of field created by the large aperture. You can hardly see the ocean.

"The same exposure can be achieved with different combinations of aperture and shutter speed. Fast shutter speeds and larger apertures freeze moving objects and soften background details [like the last image above], while slow shutter speeds and small apertures blur moving objects and bring out background details [like the first image above]." This is directly from my camera's manual and I can honestly say I "get it". Do you?