Nick Carver Photography Blog

Photography Tips, Tutorials, & Videos


Common Misconceptions: High ISO Noise

The Misconception:

Digital noise caused by a high ISO setting will ruin the image.

Why This is Wrong:
Alright here’s the deal, high ISO noise is not nearly as big a problem as people make it out to be. True, higher ISO settings result in more digital noise. No doubt about that. But it is very unlikely to ruin your shots. The final presentation size must be taken in to account when determining whether or not digital noise is something to be worried about. Sure, the maximum ISO on your camera will exhibit quite a bit of noise when you look at the image magnified 100% on the computer. But that’s not an accurate representation of the image. How often do you print that big? And even if you do print that big, how often will you view that print from just inches away like you do on your computer?

It’s tempting to judge photos at full magnification on the computer, but resist the urge. Everything looks bad that big. Don’t believe me? Take a headshot of yourself then see how you like critiquing the image at that high of a magnification (look at those pores!).

This is why when I analyze film negatives on a light table, I don’t use a 10x magnification loupe even though they do exist. I use 4x for most viewing and an 8x only if I want to really critique a negative. If the loupe magnifies the image too much, the negatives just start to look soft and grainy. And it wouldn’t be a realistic critique of the image because it’s not like I’ll be blowing up the image to those magnifications, and even if I do, people won’t view it from inches away.

High ISO Noise

Below are 100% magnification crops from the original 12-megapixel image (above)
On the left is ISO 100 on my first-generation Canon EOS 5D,
on the right is ISO 3200 (the max ISO).

The noise is, of course, noticeable in these magnified views, but how big is the image
really going to be viewed? This noise won't be noticeable except for at very large
print sizes. Plus, newer cameras will have much better high ISO performance
than my out-dated 5D.

High ISO Noise

The Truth:
Unless you print really big, high ISO noise ain’t going to ruin your shot. And if you do print big, it still won’t be as big of an issue as you think. The bigger the print, the further away you view it from. And besides, most people’s pictures end up on Facebook barely bigger than a greeting card. Noise won’t show up on an image that small. You may see it because you know it's there when it's blown up, but others won’t see it.

Yes, you should use the lowest ISO you can in any given situation just so you don’t have needless image noise, but sometimes you need an ultra-high ISO to get the shot. If you do, don’t worry about the noise. Know that it’ll be there, but don’t let it prevent you from taking the shot. Like I tell my students, “better to have the image with some noise than no image at all.”

My Thoughts and Rants:
As far as I’m concerned, high ISO noise is basically a non-issue today. Every new generation of camera is getting better and better at reducing digital noise. Today’s cameras are so good at high ISOs that it’s practically not even worth talking about. Plus, no one prints anymore (which is a tragedy in its own right). It’s all Facebook, Flickr, email, slideshows, photo books, iPhones...all great ways to share photos, but they simply don’t show the images blown up very big. So why are we even talking about noise?

And remember that no one else will ever notice the digital noise in your images. Your family, friends, clients - they won’t see it. Other photographers will, but who wants to impress them anyway? Other photographers are un-impress-able.

There are a thousand things that will ruin your photos. Digital noise is number 999. Good technique, good light, good composition, good subjects...Focus on that.

What is ISO and What Does ISO Mean?

What is ISO and What Does ISO Mean?The Misconception:
What does "ISO" mean? Ask anyone seemingly "in-the-know" and they'll tell you "ISO" is an initialism for "International Standards Organization" and thus it is pronounced "eye-ess-oh." Sounds pretty convincing, but this is false.

Why This is Wrong:
There is no such thing as the "International Standards Organization." Go ahead, Google it. It doesn't exist. So then what does "ISO" stand for? Nothing. It's not an initialism or an acronym.

Allow me to explain...

Here's where the confusion comes from: although there isn't an "International Standards Organization," there is an "International Organization for Standardization." The International Organization for Standardization is a corporation based in Geneva, Switzerland that sets all sorts of international standards for manufacturing and engineering, one of which is film sensitivity in photography. Their whole deal is getting the world on the same page with standard regulations, measurements, and certifications.

Then what is "ISO?" It's this company's name, that's all. No different than "Pepsi" or "Honda." But "ISO" obviously is not an initialism or acronym because the correct acronym (in English anyway) would be IOS. So then what does ISO mean? Well, it's derived from the Greek root "isos," which means "equal" - like in "isotope" and "isosceles." And if you look at the website for the International Organization for Standardization, you'll find an explanation on why they chose this Greek root instead of an acronym to represent their company (source:

Because 'International Organization for Standardization' would have different acronyms in different languages (IOS in English, OIN in French for Organisation internationale de normalisation), our founders decided to give it the short form ISO. ISO is derived from the Greek isos, meaning equal. Whatever the country, whatever the language, the short form of our name is always ISO.

Couldn't have said it better myself.

The Truth:
So "ISO" is not an acronym. No doubt about that. It's just a company's logo written in all capital letters derived from the Greek root isos. And just like you wouldn't spell out "PEPSI" every time you ordered one, you shouldn't spell out "ISO" every time you talk about it. That's why "ISO" is correctly pronounced "EYE-so." No matter how many times you hear it pronounced "eye-ess-oh," and even though everybody and their mother says it "eye-ess-oh," it just simply isn't correct. Doesn't matter if a guy has been taking pictures for decades or working with ISO standards for 50 years, if he says it "eye-ess-oh," he's wrong.

And just for good measure, here's a video summarizing it all:

My Thoughts and Rants:
Alright, I'll be honest. For awhile I was guilty of thinking ISO stood for International Standards Organization and for years I pronounced it "eye-ess-oh." That was based partly on misinformation from an online resource (What?! You mean Yahoo Answers isn't always correct?) and mostly from my own assumptions. After all, it made perfect sense. But that's what happens when I assume. I make an ass out of u and me.

So I can't really fault people for saying it "eye-ess-oh." It's in all capital letters so it certainly looks like an acronym. And the majority of shooters say it that way even though it's incorrect. But hey, just goes to show you how quickly false information can become "fact."

My only rant on this is that a couple years back I saw on Yahoo Answers that someone posted a question asking what is ISO and what does ISO stand for. Some know-nothing do-gooder happily answered with "It stands for 'International Standards Organization.'" Seeing this error, I politely corrected the answer with the information I stated in this blog post. All was finally right in the world. But sure enough, a few days later I get a notification that someone has "improved" my answer. I go to check it out and some idiot changed it back to the wrong answer! 

Don't get your information from some dumb yahoo on Yahoo Answers. And don't let anyone try to correct you into saying it the wrong way. It's "EYE-so."

Everyone say it with me now: EYE-so!


The excellent video and audio production was done by my brother Blake Carver. Check him out at

Common Misconceptions: Reading the Histogram

The Misconception:
The histogram for a correctly exposed image should not be touching the edges of the graph and should be more towards the center.

Why This is Wrong:
A histogram is simply a graphic representation of the range of tones in an image. By looking at each individual pixel, analyzing its brightness, then placing that pixel on a graph in the corresponding spot for its brightness, a histogram develops peaks and valleys that indicate when you have a large amount of a given tonality (the peaks) and a small amount of a given tonality (the valleys). Dark tones are always on the left side of the graph, light tones on the right.

For instance, this histogram indicates that the image it represents has a large amount of dark tones in the photo:

How to Read a Histogram

Here's the photo it represents:

Laguna Beach, CA

So when someone says "the histogram shouldn't be too close to the edges - you want it towards the center of the graph," they're basically saying "your image should have minimal highlights and minimal darks - the image should be largely middle-toned."

I doubt I need to point out why that logic is absurd.

Of course we want highlights and darks in our images! Sometimes we want a lot of darks or a lot of highlights! That's called contrast and it's a good thing. Without darks and lights in the image, we'd have no texture, no shadow, no light.

Most of my favorite images are very dark and would have a histogram heaviest on the left. Here's just a few:

How to Read a Histogram

How to Read a Histogram


How to Read a Histogram


Many great photos have bright, blown-out areas in the photo, which sways the histogram to the right. Like these:

How to Read a Histogram


How to Read a Histogram


So the only time you should have the histogram away from the edges and more towards the center is when you want the image to be largely middle-toned.

The Truth:
When reading a histogram, there are no hard, fast rules to follow when analyzing it. You have to look at the image it corresponds to and analyze whether or not the histogram makes sense for what you want to the image to look like. When you want the image to be dark and moody, the histogram should be towards the left. When you want that bright, airy feel, it should be heavy on the right.

If you want to create a silhouette, your histogram better damn well be smashed up along the left edge of the graph. When you have pixels butted up against the left side, that means you have complete blacks in the image. Since silhouettes should be completely black, the histogram should be touching the left side.

How to Read a Histogram


When you want bright, blown out backgrounds, the histogram should be touching the right side of the graph.

How to Read a Histogram


So look to see if the histogram makes sense, not whether it's touching the edges or not.

My Thoughts and Rants:
Listen, folks, if you want to speed up your progress and learning in photography, don't look for good information in forums, Flickr comments, beginner's blogs, camera clubs, and that friend of yours who "knows a lot about photography". I know it sounds like a good idea to immerse yourself completely in photography through clubs, websites, forums, etc. but you'll be much better off if you stay away from them. These sources spread far more incorrect information than correct information. I'm not exaggerating either. I literally think that a solid 60%-80% of the free information you get from these resources is incorrect.

And I'm speaking from experience. I have students of all types, and some of the toughest ones to teach are those who have done the most "independent study" by browsing online forums and who have the most confidence in those sources. There is just so much wrong information to clean up and they are often utterly convinced of their knowledge (because it did come from user "CanonLuvr50" at after all).

Now I'm not talking about books and articles from reputable sources. Independent study from the likes of Ansel Adams, John Shaw, Jim Zuckerman, and Ken Rockwell - by all means, please read on. These guys know their stuff. They have a track record. They aren't beginners.

But everyone has an equal voice on the internet now. There's no entrance exam before posting advice to a forum. This histogram business is just one tiny example of what happens when people with too little knowledge have too much of a voice. So before you listen to another photographer for advice, technique, or information, analyze their work and their philosophy. If you like their work and their approach to taking pictures, listen up. If you don't like their work or the philosophy behind their techniques, move along (and this includes me). If you've never even seen their work, then it's elementary.

Immerse yourself in what those you look up to have to say. For me, it was Galen Rowell, John Shaw, and Ansel Adams. And immerse yourself in your own photography - take tons of pictures! You'll learn more from your idols and your own mistakes than from any forum user.