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Understanding the f-Stop, Shutter Speed and ISO

One of the problems I see the most when people ask, “why isn’t my photograph looking the way I want it to look after I take the picture?” is that they let the camera do all the setting for them. What they don’t understand is that the camera can’t handle the extreme lighting conditions like our eyes do.

The secret of successful photography is when you play with the f-stop, shutter speed and ISO, but you must understand the basics before you can really push these three main components. These three components determine your exposure. I’ll be talking about exposure in more detail later, but I want you to really understand what the f-stop, shutter speed and ISO will do for you macro photographers.

Yes this is for the beginner photographer, but I always say you never know when you may learn something new if you already know the f-stop, shutter speed and ISO, so keep reading…

I’ve combined all of the elements in one blog post so you can grab this information while you’re photographing.  This way you have everything in one shot while you photograph, no pun intended…hahaha I couldn’t help myself! So let’s get started…

Most important for Macro Photographers is the f-stop.

When we get up close we lose what’s in focus. Your f-stop number will determine what’s in focus so you really must master the f-stop which is the number you’re using to open and close the aperture.

The aperture is like the irises in your eyes. Just remember that the higher the number the more in focus your shot will be, but know that f-22 lets less light into your camera and in turn you’ll need a longer shutter speed to let the light into your camera. For example, say I’m photographing a beautiful flower outside and I want to use f-22 with my natural light conditions. I’ll need to have my settings at f-22 – shutter speed 1/125 sec – iso 100 BUT if I change my f-stop number to a 2.8 that means I opened my aperture larger so it will let more light into the camera and to get the same good exposure I’ll  have to set my shutter speed to  1/4000 (really fast open and close of shutter)  ISO 100 or the picture will be blown out (white).

The f2.8 – 1/4000 – ISO 100 will be less in focus than the f-22 – 1/125 – ISO 100 but they WILL both have the same exposure (not too dark and not too light in the picture) depending on your conditions.   If you’re outside look for a shady place to photograph. NO harsh light or shadows for now.


Shutter Speed

The next most important tool to get that shot you want is to learn the shutter speed. This is how fast the shutter opens to let light into the camera.

You set the f-stop (the number of the opening of the aperture)  look into your camera and look at your meter. Move your shutter speed number up or down until you have it in the middle of your meter.

I talk to you in more detail in my video on what the shutter will do for those close up shots you’re working on.  But know that if you want a bug say flying to the flower you’ll need a faster shutter speed to capture the be and if your shutter is slow you’ll need a tripod or bump up the ISO.


The ISO is the next part of taking your picture to make a good exposure.  Start on a low number like 100.  If you don’t have enough light coming into the camera with the f-stop and shutter speed you want it’s now time to push up the ISO.

Google your camera to get an idea of how much you can push up your camera’s ISO.  Here is a great site to plug in your Camera:  If you go too high you’ll get grainy and ugly shots so you need to pay attention on how much you can push your ISO.

Definition: 0:43
Looking at the camera 1:05
The 3rd element to Exposure 2:17
Macro with a Tripod – slow shutter: 3:33
Photographing bugs or subjects needing a faster speed: 4:48
Overview and my question 6:22


I realize that this can be a challenge to understand each of these settings on your camera but you REALLY will understand what you can do while you’re photographing if you get these 3 tools down.  Work on manual mode and play with the f-stop – shutter speed and ISO.  Once you get the basics down then you’ll push them to create your own stories with your images.  Trust me! It’s hard I know!  But if you really want to push your creative spin in your work this is where you start.  This is, “The Secret of Successful Photography.”

Of course, if you have any questions please ask below in the comment section and if you feel this was informative and helpful please share with your friends.

What’s your thought process as you photograph? Have you ever thought about the f-stop, shutter speed or ISO?

Cheers to the f-stop, shutter speed and ISO! Knowing its secrets will make your work successful because YOU will make your work…the camera won’t.

Janice Sullivan

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