Histogram

Make "Check Your Histogram" Your New Year's Chant

© Rick Sammon. Purchase through my SmugMug site.
On my all my workshops, "Check Your Histogram" is the daily chant.

Your camera's histogram is your light meter. It will tell you if parts of your image will be overexposed and if the shadows will be blocked up.


The basic concept is to "move the histogram to the right." You do that by increasing the exposure until the "mountain range" (which shows the distribution of light levels) is mostly on the right - but without a spike on the very, very right. Most of your image data is on the right, which is why your want your histogram on the right.

Photographs © Rick Sammon
If you do get a spike, the brighter parts of the image will be overexposed, as illustrated by the picture on the right. The image on the left is properly exposed - you can see details in the white feathers.

Photograph © Rick Sammon
If you do get an overexposed area in an image, you can try to rescue it with the Shadow/Highlight control in Photoshop and Lightroom. But it's best to get the best in-camera exposure - by checking your histogram.

Explore the light,
Rick

Get it "Right" With Your Histogram



Here's a guest post by my friend, and DPE podcast co-host, Juan Pons

Good advice, Juan. Thank you for sharing. I just love your bison in the mist shot!
 
“Expose to the right” is an expression that you may have heard before, but my experience has been that most folks don’t understand what it means or how how to do it.

In simple terms what this means is that in order for you get the absolute best image quality your digital camera sensor can produce you should be slightly over-exposing your images. I know this does not sound like good advice, but bear with me for a minute, there is a very good technical reason for this.

The imaging sensor in your digital camera is composed of millions of little light sensors (as many as your camera has Mega pixels), and each of these sensors measures the intensity of the light that falls upon it, the camera then takes these millions of measuring points to create an image. However these sensors are not equally as good as measuring light at all levels, actually they are magnitudes more sensitive near the highlights than they are near the dark areas.
 ExposeToTheRight

What this means is that your camera can record much more detail in the brighter parts of your image than the darker parts. Therefore to get the best image quality from your camera you need to slightly over-expose your images or “shoot to the right” in order to fully take advantage of your sensors capabilities.

The tricky part here is not to over-expose too much so as to “blow out” your highlights, because if you go too far you will lose all the detail in those blown out areas. How do you know how much to over-expose? This is where your camera histogram comes in handy. Your cameras histogram simply displays to you how much information has been recorded at each light level, from dark (left) to light (right). A normally exposed image will have a histogram that shows most of the information bunched up in the middle.

Exposing to the right means just that, to expose your image such that the histogram shows the majority of the data bunched up on the right side of the histogram as opposed to right smack in the middle.

HOWEVER, you need to take care not to let that data “bump” up against the right edge, because that data will be lost; this is where those over exposed flashing alerts that are part of most cameras preview screens come in handy. Yes, sometimes you will want pure white, blown out areas in your image, and that is ok, just use your judgement here.


When you look at these RAW files (this will only work when shooting RAW ) in your favorite image processing software, the images will most likely appear a bit over exposed, but that is ok, as you can easily adjust the exposure to make the image look “right”.

Quick Digital Imaging Tip 14/101: Set Your Camera's LCD Monitor to Display the Image and the Historgram



This is #14 of 101 digital imaging tips I plan to post here over the next few months. Stay tuned.

Today's tip (from Laos): Set Your Camera's LCD Monitor to Display the Image and the Historgram.

The histogram is the best (only) way to check your exposure. If you are not checking your histogram, you are not checking to see if you have the best possible in-camera exposure.

The image on your display only gives you an approximate idea of the exposure. It's a JPEG of your RAW file.

Explore the light,
Rick

P.S. Bonus tip: Keep your radar on all the time. The opening picture for this post is one of my favorite images from today. I got the idea after seeing the scene in a remote village: a young woman hanging several weaving on a line. I noticed the opening in the weavings and thought that it made a perfect frame for the woman. I simply asked her to walk into position and took a few shots.

Actually, I asked my guide, Vong a thit, the best guide in Laos, to ask the woman to pose for the photograph. Vong's email address: vongla@yahoo.com.

Hey, I know the image below is just a snapshot. I just wanted to give you a behind-the-scenes look at the village.


I also shot the image vertically. It's usually a good idea shoot a scene both horizontally and vertically – because you may prefer one over the other at a later date. Which version do you prefer?


If you like digital imaging tips like this one, as well as general photography tips, check out my 24/7 Photo Buffet app.

SLR Snapshots to Great Shots Week: Last Day - Avoiding Flats


This week's blog was devoted to SLR tips - in honor of the Wiley DVD (available this fall) that I was shooting on the new Canon Rebel T1i . All the photos were taken with that camera. It's a also to celebrate my new SLR classes on Kelbytraining.com (available now).

Today is the last day of T1i posts... for a while, at least.

The title of today's post, Avoiding Flats, refers to avoiding flat pictures - in other words, pictures that don't show the full brightness range of a scene . . . pictures that lack contrast.

Pictured here is our entire DVD crew: David Leveen (creative director), Jen Maihack ("student") and yours truly. The top row of pictures was shot with the camera set to the Monochrome Picture Style. The pictures are okay - but they were taken in the shade and lack contrast, as indicated by the histogram (spaces at the left and right of the "mountain range").

By simply moving the shadow and highlight triangles inside the "mountain range," the contrast was improved. See the bottom row of pictures. Yes, it's a subtle change, but enough to make a difference - in my books anyway. Adjusting Curves (making an "S") can also improve a photo's "looks."

So when you do a get a flat photo, fix it in the digital darkroom.

And, please check your histogram on your camera's LCD monitor after you take a shot. It's the best way to determine a whether or not you have a good exposure.

Happy 4th,
Rick