Home  Camera and Photography CheatSheets  Must Have Accessories  FAQ  About Us  Checkout 
Our Goal:
To help you take better pictures!!
Sign-up for our
Digital Photo
e-Tips by email
Sign up for e-Tips by email
Site Search:

PhotoBert CheatSheets
Simple tips to
help you take better pictures

Tips for Better Pictures

 

Today's e-tip:

Using
Program Shift/Flexible Program
on your DLSR


Your digital camera doesn't see the way you do. Understanding the differences in the way you and your camera sees is the start of taking great pictures.
Using Program Shift/Flexible Program on your DLSR
Your camera needs to allow just the right amount of light in to take a picture that isn’t too light or dark. This is called the "exposure". Given an amount of ambient light (e.g., sunlight, flash, light bulbs, etc.), there are 3 controls on your camera that affect the exposure:
  • Aperture;
  • Shutter speed; and
  • ISO Speed.
If you set your camera to any of the "automatic" modes ("Auto", "P", "A" (or "Av") or "S" (or "Tv"), your camera tries to set the aperture, shutter or both (depending on the mode) for you so the picture comes out properly exposed. It usually does a pretty good job of this. (For more info on these modes, see this eTip).
Exposure Triangle

The Exposure Triangle
 showing the 3 components of exposure.


What's wrong with AUTO mode?

If you shoot in "Auto" mode, you lose all control over your camera (except aiming it). Feel free to skip this next sentence if you get offended easily and are shooting in "Auto" mode:
     If you are shooting in "Auto" mode, you might as well be shooting with a $20 camera.


Shooting Mode Selector
Sample Shooting Mode Selector
"Program Mode" is better than "Auto"
If you shoot in "P" (Program mode), your camera will still decide most things, but this mode gives you more control than "Auto" mode. In "P" (Program) mode, you can use a feature called "Flexible Program" (Canon) or "Program Shift" (Nikon).

Flexible Program or Program Shift lets you change your aperture and shutter speed while the camera maintains the proper exposure. Most cameras work the same way – once in program mode, with the exposure system on (you generally just need to press the shutter button half-way to turn it on), you just turn a dial (usually the "main" dial, if your camera has more than one dial). As you turn the dial, you can view the changing aperture and shutter speed in the viewfinder, or LCD display. Turning the dial doesn’t change the exposure, it just selects one of multiple equivalent exposures. It does this by changing the aperture and shutter an equivalent amount.

Equivalent Exposures
For example, if your camera initially selects this exposure:
ApertureShutter
f81/200 second

Turning the dial one-click in one direction will select
ApertureShutter
f111/100 second

And turning it in the other direction will select:
ApertureShutter
f5.61/400 second

Exposure Equivalency Graph

Exposure Equivalencies

The aperture size is on the left; shutter speed below
(e.g., 15 = 1/15 second shutter speed).

Each of the round dots on the graph along a single diagonal line indicates an equivalent exposure.

For example, f16 at 1/8 sec. shutter speed is equal to:
f11 @ 1/15 sec
f8 at 1/30 sec
f5.6 at 1/60 sec
f4 @ 1/125 sec
f2.8 @ 1/250 sec
Each of these exposures is exactly the same – that is, each will let exactly the same amount of light to reach your camera’s sensor.

By going from f8 to f11, the aperture is allowing 1/2 of the light to reach the sensor, but by going from 1/200 second to 1/100 second, the shutter allows twice the light to reach the sensor – thus the same amount of light reaches the sensor.


Why do this?
The main reason for doing this, is you may want to use a wider lens aperture to provide a blurred background, or you may want to use a smaller aperture to provide a sharper background. Changing the aperture changes the depth of field, which allows you to determine how sharp you want a background to be.

Or, you may be shooting a soccer game, and you need a faster shutter speed to stop the action.
Shooting in "P" mode, allows you to decide, once the camera sets the exposure, what aperture or shutter speed you want to use. You may not always want to change it, but you can if you want to.

You could always shoot in "A" (or "Av") mode (aperture priority) to give you more control over your aperture. This is what I almost always shoot in, but, shooting in "P" mode can give you the similar control and can be a first step to leaving "Auto" mode. The main difference is in "A" mode, you only need to set your aperture once – in "P" mode, each time you take a picture, you’ll need to adjust your camera’s dial in order to change the aperture or shutter.

The image below shows the difference the aperture can make in how the background looks. These images were taken with a 70mm focal length (full-frame). I focussed on the wooden-parrot and you can see how changing the aperture had a profound effect on how sharp the backtround is, but little to no effect on the subject.

Depth of Field (DOF) example
Sample Shooting Mode Selector

Having control over the aperture provides a huge amount of creativity control - it's one of the most important aspects of taking good images.


Limits
There are limits to how far you can adjust the aperture. Your lens aperture has a "maximum" aperture – usually f2.8, f4.0 or f5.6. So, you can’t go beyond that. Some lenses have a variable aperture. When zoomed to wide-angle, they have one maximum f-stop; when zoomed to telephoto, they have a different maximum f-stop (always smaller).

The other limit is that you could select a small lens opening (e.g., f16) which would cause your shutter speed to be so slow, that you wouldn’t be able to hand-hold your camera without blurring the picture. So, you need to watch the shutter speed to make sure it’s not too slow. You can usually view the shutter speed in the viewfinder and/or LCD display (if your camera has one).

Raising the ISO speed can help avoid a shutter speed that's too slow.

Viewing the shutter speed in the LCD
Sample of viewing the shutter speed in an LCD


ISO Speed

The ISO speed on every digital camera determines how sensitive to light the camera’s sensor is. The higher the ISO speed, the more sensitive the sensor is, thus, less light is needed for a good exposure.

If you are shooting in low-light conditions, you’ll want a higher ISO speed; on a sunny day, you’ll want a lower ISO speed. Lower ISO speeds yield better quality images, but sometimes you need to increase the ISO speed to get a good exposure. Digital cameras have a feature called "Auto ISO" – this feature will increase the ISO speed as the camera thinks is necessary for you to get a good exposure. If you don’t want to have to fuss with the ISO speed, "Auto ISO" is a good option for you.

For more information on ISO speeds, see these eTips: ISO Speed - When to Change it.

 


Summary
Understanding the components of exposure (aperture size, shutter speed and ISO speed) is critical to getting great images. You can't learn everything in one day - it takes time and a bit of effort on your part. Learning a little at a time is the best way to do this.

If you are an "Auto" shooter, start by migrating to "P" (Program) mode and start using the Program Shift/Flexible Program feature of your camera. It's a great start to leaning how to be creative with your camera.

For more info on shooting modes, see this eTip: Shooting Modes Explained - Unraveling the PSAM (PTvAvM) Maze



Related products to help you take better pictures:

Sirui T-1004X Traveler Tripod
This tripod is ideal for all cameras and it's the perfect tripod for travel. It's sturdy, but light and small. It easily packs...

Sirui K-10x Ball Head
Fantastic quality combined with a great price makes this your best choice in an industry-standard ball head.

Sirui EP-204S Monopod
This is the "Swiss Army Knife" of Monopods! This isn't a tripod - and it isn't a monopod. It's actually a hybrid....

Gray Card (8in x 10in)
A gray card allows you to get the perfect exposure & white balance. It's the perfect low-tech solution to...

Smartphone Bluetooth Remote Shutter Release
Bluetooth Remote Shutter Release for Smartphones is the ultimate selfie-tool. This tiny device fits easily on a key chain, so you can always..

Smartphone/Camera Tripod
This tripod is a portable, lightweight and great for holding your smartphone (with tripod holder) or small digital camera. It collapses to...

Camsafe V18 anti-theft Camera Shoulder Bag
This PacSafe camera bag is the best bag I've ever owned! If you're like me, you've gone thru a lot of camera bags...


  © Copyright 2001-2018, Bert Sirkin
Contact Us Email Us  
NEWPROD