Archive for the ‘camera’ category

Tips for New Photographers

September 28th, 2009

Came across this article from a Twitter feed. Thought it was pretty interesting so I wanted to share it with my readers as well.

11 Tips for Beginner Photographers

I really like the suggestion to keep a journal of things you want to come back and shoot. I always see things that I’d like to take a picture of, but never remember to come back. I’m going to start taking pictures on my iPhone, which is always with me, and then page through them as a reminder to come back with my dSLR. Anyone else find anything useful?

The Basics – Aperture

September 14th, 2009

Aperture is one of those photography terms that intimated me at first. It sounds quite technical, and even the units, F-Numbers, don’t make a lot of sense. Changing your aperture is a very powerful tool to a photographer, and there are many reasons why you’d chose a certain value, however, it again all comes down to light. In combination with shutter speed, aperture controls the amount of light hitting your image sensor. The more light, the brighter your image, the less light, the darker your image.

Technically, aperture refers to the size of the opening in the lens. Take a look at the example below. The top image is a wide or large aperture (lots of light), while the bottom image is a smaller aperture (just a small amount of light).

The other hard to grasp part of aperture is the numbering system. Aperture uses F-numbers or F-stops. It seems counter intuitive to me, however, the smaller the number, the larger the opening. So in the pictures above, the top lens might have an aperture of f/2 while the lower image has f/16. A trick I use to help me remember how F-numbers work was given to me by my photography professor… “think about inflating a cartoon bike tire. If you inflate it with a lot of pressure, the hole in the middle will get smaller” More pressure = tighter aperture = higher F-Number. Not sure if that helps you, but it works for me.

These images are all shot keeping the shutter speed constant and just adjusting aperture (which will cause them to be under/over exposed).

Overexposed with wide aperture: 1/10 sec, f/5.6

Over exp Wide Ap

Proper Exposure with medium aperture: 1/10 sec, f/11

Expose Med Ap

Underexposed with small aperture (big f-number): 1/10 sec, f/22

Under expose small Ap

Aperture also has another effect on your images beyond how bright or dark your image is. After all, why would you need 2 ways to control this, shutter speed and aperture. What aperture does is also change the amount of your image that is in focus. This is referred to as the depth of field. I’ll cover depth of field in a later post, however, to illustrate the effects, take a look at the three images I’ve shot below.

Exposed properly, but with different aperture/shutter speed combinations, so you can see the depth of field effects.

½ sec, f /22 (all 3 quarters are in focus) – Slow shutter speed because aperture is small. This lets in enough light.

Big DOF

1/10 sec, f/11 (Center quarter is in focus, but back is out of focus, and most of front is out of focus) – Faster shutter speed because less light is needed when aperture is larger.

Med DOF

1/40 sec. f/5.6 (center quarter is the only one that is in focus) – Even faster shutter speed because aperture is all the way open.

Small DOF

This was another resource that I found helpful if you want to learn more:

http://www.photoaficionado.com/situationroom/aperture.html

Shutter Speed

August 29th, 2009

Shutter speed refers to the amount of time that your image sensor is exposed to light. Refer back to my earlier post on the anatomy of a DSLR, and you’ll see that the shutter is in front of the image sensor. So, the “faster” your shutter speed, the less time light (which is the image) is hitting the image. “Slower” shutter speeds, means that the image sensor is exposed for a longer period of time.

Shutters are normally very fast… fractions of a second. That’s all the light you need to make a photo. Shutter speeds range from about 1/6000th of a second to about 8 seconds. The light you have available to take a picture, determines how you set your shutter speed. 8 seconds, (denoted 8” on the back of the camera) would be used for incredibly low light (ie, Taking pictures of the stars). 1/6000th of a second (denoted 6000 on the back of the camera) would be used for taking pictures when there is a lot of light available (ie, middle of the day, pointed at the sun).

Under normal, daytime conditions, I shoot in the range of 1/60th to 1/3200th of a second. I generally try to use the fastest speed that the light will allow. The faster the shutter, the less chance I will cause the image to be blurry by shaking the camera. This type of blur is called “motion blur”, and causes everything in your pictures to appear out of focus. If I’m going to hand-hold my camera (not use a tripod), I won’t set it below 1/60th of a second. It is next to impossible to hold still enough at this speed.

Take a look at the three photos below to see the effects of shutter speed. I’ve kept all the variables the same (Subject, time of day, aperture, white balance, iso camera location) except shutter speed.

This image has the “fastest” shutter speed. 1/2500th of a second.

Sunglasses 1/2500 sec f/5.3

This image is a little slower. 1/2500th of a second.

Sunglasses 1/1250 sec f/5.3

This is the slowest image 1/800th of a second.

Sunglasses 1/800 sec f/5.3

Notice that the photos get darker the faster the shutter speed is. This is because less light is hitting the sensor. 1/2500th of a second’s worth of light vs. 1/800th of a second.

So, when shooting in the manual mode, I set the aperture, and then adjust the shutter speed until the image is exposed properly. The camera will also do this automatically for you if you shoot in Aperture Priority Mode.

Photography: It’s all about Light

August 21st, 2009

When thinking about photography, it all really comes down to light. That’s what goes onto the cameras sensor, and that is what makes an image. Exposing the perfect picture comes down to your ability to control the light that comes into the camera. There are three settings on your camera that really control the light coming in.

  1. 1. Aperture: The size of the “hole” light comes through to your sensor
  2. 2. Shutter Speed: The amount of time light is being captured by the sensor
  3. 3. ISO: The sensitivity of your sensor.

I’ll cover each of these in separate blog posts. But being able to control these three settings are what will enable you to capture that perfect shot. These all three come together to become the “exposure” of the picture. You’ve probably heard the term “overexposed” or “underexposed” before. By changing aperture, shutter speed, and ISO, you can control the amount of light in the picture and get the perfect exposure.

Below are three examples of exposure:

Underexposure

Underexposed

Overexposure

Overexposed
Correct Exposure
Exposed

Using Autofocus

August 19th, 2009

The ability for a camera to automatically focus is awesome. The fact that your camera can look at an object, determine if it is sharp enough, and change the focus blows me away every time. When I first got my DSLR cameras, one thing I’ve noticed is that it was unpredictable on what it would focus on. I’d look through the viewfinder, and want to focus on the person in my shot, and it would focus on some leaf in the foreground. Or it would focus on the closest person instead of the person in the middle. Turns out, my Nikon has some settings for the focus mode that I didn’t know about. The factory had it set to focus on the closest object, regardless of where it was. This wasn’t working for me, because I didn’t always want the closest object in focus.

What I’ve done to simplify my life and make my autofocus only focus on what is in the direct center of my viewfinder. Looking through my Nikon, (D40) I have an indicator that looks like:

These boxes are the focus area indicators. I’ve changed the settings in the back menu (check your manual to see what menu), so that only the center square is put in focus.

I know what you are saying, “what if I don’t want the center to be in focus, what if I want something on the right or left to be in focus. I that case you put the item you want to focus on in the center brackets, press the shutter button half way down and then re-compose you image. This blog talks about some of the other features of autofocusing that I won’t rewrite here: http://www.kenrockwell.com/nikon/d80/af-settings.htm

I also noticed that sometimes the camera wouldn’t focus, it just kept searching, and never finds a focus distance. The autofocus in your camera uses lines of contrast to focus. So you need to look at the edge of an object to get the camera to focus. It you are trying to focus on something all the same color, the camera won’t know how to make it sharp

Becoming Master of Your Domain: Camera Modes

April 9th, 2009

One of the first things that new camera owners start to play with on their DSLR is the little Mode Dial on the top of the camera:

Nikon

inhandNikon

Canon
inhandCanon

Everyone is always tempted to just put it on Auto, and leave it, but here’s what these different Mode Dial symbols mean (I’m going to focus on Nikon and Canon):

Nikon Canon
P P Program Mode: this is almost automatic, but allows you to change a couple settings like ISO and white balance. It is a way to override some of the decisions your camera’s auto sensor is making.

S Tv Shutter Priority: You chose the shutter speed, and the camera selects an appropriate aperture value. This is a semi-auto mode, but it is great for getting a specific effect.

For example, it you want to get a crystal clear picture of a track runner, you need a fast shutter speed to stop the runner. Otherwise you will get a blur. In this mode, you set the shutter speed fast, and the camera picks the appropriate aperture to get enough light.

A Av Aperture Priority: You chose the aperture value, and the camera selects an appropriate shutter speed. This is a semi-auto mode, but it is great for getting a specific effect.

For example, it you want to take a “selective focus” picture of a flower (flower in focus, background out of focus) you need a wide aperture (low f-number). This will put the flower in crisp focus, and have the background all out of focus. The camera then compensates with the correct shutter speed to let the right amount of light in.

M M Manual: Allows everything to be set by the user. I shoot most of the time in this mode.

Auto Green Box (Auto) Auto: “photography for dummies”. This setting uses the camera’s image sensor to decide all settings. It usually gets close, but I’ve found that I can usually do a better job controlling brightness, white balance, and shooting style using the Auto Mode

Icon Icon Scene Select: the second half of the camera mode dial has little pictures on it that are meant to specify a shooting scenario. They basically change some of the pre-set features for each scene type. I find them useless.

Anatomy of a DSLR

April 6th, 2009

Now that you have your DSLR, lets look at the pieces that make it work. Below is a very crude diagram of a DSLR. I’ve called out each of the major components:

DSLR Diagram

1. Lens Hood: this is used to flag light from the lens. I’ll cover what flagging means later, but we want to block extra light coming in from the sun or lamps from hitting our lens, and only have the light from the subject enter the lens.

2. UV filter: this is a little filter that covers the front of your lens. These are about $20 and protect you lens from scratches (it’s much cheaper to replace the UV filter than the whole lens).

3. Focus ring: enables you to manually focus the lens. When you are in auto-focus mode, you won’t need to use this at all. Depending on you lens/camera, it can also be located at #5.

4. Zoom: changes the zoom of the lens, brings objects closer or further away.

5. Focus ring: see #3

6. Prism: A mirror to reflect what is being seen by your lens up to you eye.

7. Diopter: a slider next to the viewfinder that allows you to adjust the focus. This is used for people who need corrective vision. (most people just leave it alone and look through the lens with their glasses)

8. Viewfinder: Look through the viewfinder to see what you have in frame.

9. Shutter: The shutter is what allows the light to hit your image sensor for a set length of time.

10. Image Sensor: the film of the digital camera. This captures the light, and converts it to the digital image.

11. LCD: The screen on the back of your camera that allows you to modify the camera settings and review your images after you captured them.

12. Mirror: is in the down position to allow the image to be reflected up to the viewfinder. When you press the shutter button to take a picture the mirror flips up and lets the light through the shutter onto the image sensor.

13. Aperture/F-Stops/Diaphragm: Aperture, is measured in f-stops. This is the hole in the lens that allows the light to pass through. It is made up of blades that form the diaphragm. The larger the f-number, the smaller the hole in the diaphragm is. I will cover how this works in detail later.

14. Lens elements: allows the lens to focus and gather the light onto a point source (in this case, the image sensor)

15. Objective Lens: This is the front lens.

Buying Guide – Pro level D-SLR’s

April 1st, 2009

If you have a few thousand dollars to spend, and really want to look like you know what you are doing, I’d recommend you look into a pro level DSLR. To be totally honest, I don’t have the cash for these, so I’m probably not the best person to offer advice. What I can say are a few of the benefits:
• Higher Mexapixel – More sensors in the camera means higher resolution images
• Better in low light – These cameras look better at higher ISO’s
• Better Kit lenses – they pack these into the costs
• More buttons, and dials – the camera body is bigger so they fit in things like LCD displays, separate aperture and shutter speed controls, white balance buttons, etc.
• Video – some of the newer models (Canon 5D – Mark II and Nikon D90) are offering video capabilities.

Along with the higher price tag, these cameras are bigger and weigh more, so be prepared to carry a heavier load.

I’d strongly advise against spending this much money for your first camera. Personally, I got the cheapest camera I could to learn with. My plan is to continue using it till I’ve out grown its capabilities, then upgrade to something a little snazzier!!! But that’s just me.

Consumer Level D-SLR Cameras

March 23rd, 2009

So, the first question is: What is a D-SLR?
Answer: It stands for Digital Single Lens Reflex. In plain English, it is a digital camera, where you look through the lens that you actually take the picture through. (most point and shoot cameras have a separate view finder) You look down though a mirror that points out the lens. When you press the button (shutter) to take a picture, the mirror lifts up and exposes the image sensor (film) and that captures the image. Here’s a great diagram of how a D-SLR works from “how stuff works” (just replace the film with digital image sensor):

D-SLR cameras are great for photographers who consider taking pictures an art and think of it more as a hobby. These cameras allow for tons of control in how light is captured by your camera or how to compose your picture. You can also change lenses so you can take pictures in unusual situations, like super close up (macro) or things very far away (zoom). They also make it very easy to change the aperture, shutter speed, and white balance.

Consumer level D-SLR have a couple limitations compared to their pro model counterparts. First, they usually have only one dial on the camera body to change both aperture and shutter speed. This is a bit of an inconvenience, but still better than going into menus to change, like in the consumer level cameras. Also, they only have one display to show what your camera settings are (battery life, images left, aperture, shutter speed, iso, etc). This screen also shows the preview of your image, so it is has to alternate between different views when you want to change settings.

The consumer level D-SLR’s are a great entry point for someone who wants to learn more about photography, but doesn’t want to plunk down several thousand dollars to get started. I bought a Nikon D40 for around $600:

D-SLR cameras come in two parts, the body and the lens. You can buy these items separately, however, they also sell them as ‘kits’, which is a body and lens combo. You can also find them with multiple lenses, an included memory card, extra battery, etc. The one I got came with 2 Nikon lenses; an 18-55mm and a 55-200mm. This allows me to have a bit more zoom when I swap lenses. Neither of these are “high quality” lenses, but they do the trick for just learning.

This is the kit that I bought off Amazon.

Another good set of cameras to look at is the Canon Rebel. I don’t know much about the Canon lineup, but I’ve heard good things.

Consumer Model Cameras with Advanced Settings

March 19th, 2009

These cameras are generally larger and more expensive than the point and shoot cameras. The reason to use the advanced cameras over a point and shoot is they allow the photographer to change some key settings:
• Aperture
• Shutter Speed
• White balance

As you become more advanced with your photography, you will begin to use these settings to get the desired effects from lighting, focus, and color. The Consumer Models let you change these settings (although they are buried in the menus of the camera). A great example is the Canon PowerShot A720IS (http://www.dpreview.com/reviews/canona720is/). It allows the user to shoot in Manual mode (set both aperture and shutter speed) to have more control over the images.

The difference between these cameras and their D-SLR counterparts are interchangeable lenses, and on-camera controls for adjusting aperture and shutter speed. If you are shooting a lot of pictures in changing light conditions, it is pretty annoying to have to keep navigating through menus to update these settings.

All in all, these are great for cost conscious photographers who want to learn photography, but don’t want to invest in an expensive D-SLR.