Thursday, November 3, 2016

Let's talk aperture.

      Aperture is a hole within a lens controlled by a diaphragm to allow variable amounts of light through. There is a diaphragm inside the lens that controls the size of the aperture. It is easiest to think of our eyes. Your pupils dilate in low light and close when exposed to more light. The changing size of the pupils is similar to what you are doing when you change your aperture.
   
      Aperture is controllable on most cameras, but is limited by the lens. If you have a camera with interchangeable lenses you will see a marking on the lens like f/1.2 or f/3.5-6.3. This is called f-stop and it is used to refer to the size of the aperture. On a prime lens it will have a single number which indicates the largest setting that the aperture can have. On most zoom lenses you will see two numbers indicating the widest aperture at the least zoom and the widest aperture at the most zoom. This is because on less expensive lenses when you zoom in it automatically forces the diaphragm to close to a degree.

      As you probably already guessed the wider that diaphragm the more light will get to the sensor resulting in a brighter exposure. This is why cameras with a wide aperture are called fast lenses. They allow more light to enter the camera letting your shoot with a faster shutter speed. The wider the diaphragm the smaller your f-stop number.

      Think of it like your curtains. If you close your curtains on a sunny day and only let a sliver of light through it is the same as closing the diaphragm of your lens. If you open your curtains all the way you can see that much more light enters the room. If your curtains are wide open it is the same as a wide open diaphragm which would be the smaller number when setting your f-stop. My 50mm lens has an f-stop of 1.2 which is the widest setting for the diaphragm on my lens, but I can close the diaphragm to an f-stop of 22 Almost all lenses with a variable aperture will close down to an f-stop of at least f/16 so the widest aperture setting is the only number necessary to be listed for the lens. The closer that number is to 0 the more potential the lens has for shooting in darker environments: and a second very important feature of a wide aperture....BOKEH

      Bokeh is the asthetic quality of the blur produced by a fast lens; that is a lens with a very wide aperture. You see, the wider you set your aperture the smaller your depth of field. For example, if you were to take three traffic cones and set them at 2', 4' and 6' from the camera a wide depth of field would allow you to take a picture with all three cones in focus. This would be achieved by setting a smaller aperture: probably an f-stop of f/8 or more. If you shot it at f/3 and focused on the center cone then both the closer cone and the farthest cone would be blurred out of focus. A very fast lens like a 50mm f/1.2 can narrow that depth of field so much that if you focused on a persons eye the pupil could be in focus but the eyelashes could be slightly blurred.

      Here is an example of a photo shot with a wide aperture. You can see that the main subject is in focus, but the foreground and background of the picture are blurred out. (if I still had my original
image I could tell you exactly what my aperture was set at)


     Here is an example of a picture taken with a much smaller aperture: probably closer to f/16 and everything in the picture is in focus.  On a side note, we are so spoiled in the United States; this lady digging through the trash is smiling.

Monday, October 31, 2016

Understanding Shutter Speed

 
 Who wants to take better pictures?  Skip to the * if you want fewer details.

     There is way more to taking great (or even good) pictures than just owning a nice camera.  As great as cameras are these days they still can't make the decisions we can to get the images you want.

     Here are some pictures that automatic settings could never have come close to capturing.


     There are all kinds of things that go in to making a great picture.  A lot of people are only aware of exposure.  They place the subject in the center of the picture and snap the shot.  If it isn't too dark or too light they are satisfied.  There are ways to show emotion, personality, movement and to evoke feelings that you can't do with just a proper exposure alone.

     Here are some pictures I feel show emotion that required proper lighting technique, composition and camera settings.



     Great pictures are made of interesting/beautiful subject matter, proper lighting for what you wish to convey, a composition that draws the eyes around the picture and more.


     Let's start with an easy one: something we all have some knowledge of already.  Shutter Speed.

     Maybe we should start with what a shutter is.  There are actually many types of shutters.  Most, if not all, camera phones use an electrical shutter. This is just a signal that turns the camera sensor on to simulate the shutter being open and off to simulate the shutter being closed.   DSLR's use a physical shutter.  A mechanical shutter is actually a curtain (or can be a leaf shutter) which opens, allowing light in for the set amount of time and closes again when the proper amount of light has been exposed to the sensor.  

     Shutter speed is the amount of time you set for the shutter to be open allowing light in to the sensor.  If you close your eyes and then hold them open long enough to wave your hand in front of your face before closing them again your mind processes that motion, but if you had to condense all of that information into a single still image it would be a blur of your hand moving across the image.  Now, if you were able to open and close your eyes fast enough you would get an image of your hand completely still in front of your face.  

   *  So, the slower your shutter speed the more motion will show up in your picture.  The faster your shutter speed, the more motion you can eliminate from your picture.  As a rule of thumb to keep motion blur out of your image (with a standard focal length lens), keep your shutter speed at 1/160 of a second or faster for a portrait.  The shutter speed can be slower than that if you are using a tripod.  I usually am wary of shooting under 1/250 with a 50mm lens without a tripod.  Keep in mind though that  the more zoom you have, the more camera shake shows up in your picture. This will require a faster shutter speed.

     The other effect of shutter speed is how much light the sensor absorbs.  The faster the shutter speed the less the sensor is exposed to light.  That means a darker image.  If you have a slow shutter speed the sensor will have more time to absorb the light and give you a brighter image.

     I used a 30 second shutter speed in this pictures of the stars while I was in Peru.  However, I had not accounted for the spinning of the earth and when I zoomed in on the picture at home I noticed the stars all had a slight motion blur from left to right.

     For me, I want to eliminate motion blur in most of my photos.  So the faster my subject, the faster I need my shutter speed.  If I am shooting running kids. I may increase the shutter speed to 1/800 of a second.  Actually, as long as there is plenty of light, it can't hurt (as long as you don't want motion blur) to increase your shutter speed as much as you want.  I have shot at 1/8000 of a second before on bright sunny days with a wide aperture. <we will get to aperture in a future post>

Here is an image that required a slower shutter speed for the look I wanted.  I wanted to show that the train was moving in this photo so I had to choose an appropriately slow shutter speed.   I shot this in 2009 and it is still one of my favorites.

This is another one of my favorites where I wanted the opposite effect.  You know from the content that the motion is there, so I wanted to stop the motion of both the dancer and the water droplets.  (Thank you Taylor for asking for this shot- it was a fun challenge)  A lot of proper flashwork and camera settings were required to get this shot- along with an exceptional dancer!

In summrary: Fast shutter speed = less light  and less motion
                       Slow shutter speed= more light and more motion.

     Most cameras have a Shutter Priority feature that allows you to adjust the shutter speed while the camera adjusts the rest of the settings for proper exposure.  On Canon cameras it is probably labeled Tv.  This is a good way to get used to adjusting your shutter speed and understanding how it affects your pictures.

     Comment below if you enjoyed this entry.

     Also, I am an ambassador for Plexus.  If you aren't familiar with Plexus  and their health/weight loss supplements I can add you to my group on Facebook or you can watch a couple of my videos here: https://www.youtube.com/channel/UCzftvHrnVFJYeXJwE6NGKvw .  If you are intersted in ordering anything you can go to http://shopmyplexus.com/healthyjoe
     

     

Sunday, October 16, 2016

Healthy Joe introduction

Hello,

I am Joe and I am starting this blog to write about health, Plexus, photography and anything else that I may feel like writing about.

I am an average but healthy Joe and enjoy weight lifting and any action sport.  I am also a successful photographer with a studio in downtown Omaha Nebraska.  I have also started making YouTube videos with the username Healthy Joe.

If you would like to friend me on Facebook my name is Joe Chad.

If you have suggestions on what I should write about leave me a comment!

If you would like to buy some Plexus my page is http://shopmyplexus.com/healthyjoe