Monday, September 24, 2018

The focal length you choose will affect the outcome of the image.

Photograph of a beautiful Catholic Church at different distances and focal lengths.

One of the things which I frequently encourage people to do is to take a picture, then change something and take the same picture again.  Examine the two images and determine in what ways they are similar, but more importantly, different.  Then try to understand the reason why they are different, and you will have learned something.

You can do this with anything in photography really; ISO, exposure, white balance, shutter speed and aperture settings, and so on.  In the shots above, I changes my position relative to the subject (the church) and focal length I used to capture the image.

The left image used a 31 mm focal length on an APS-C sensor camera so it had a relative focal length of about 46 mm - in other words it looked "normal" (as it appears to your eye).  The right image used a 16 mm focal length, which has a relative focal length of 24 mm.  This is a wide angle setting, and it alters perspective.  You will notice that the entrance way appears much larger in the second shot and the spire seems much higher in the first.  This has to do with perspective; the way that different focal lengths alter the image, rendering near and distant features differently.

Creston granary - with and without power lines

Creston granary - with and without power lines

What has changed in the above pictures?  They are the same image, only the one on the right has had all of the power lines removed.  I did this in Photoshop, and it took a modest amount of time but nothing that was unreasonable.  The sky was relatively easy to fix as it was just a matter of replacing the cable with the same colour that was present immediately above or below it.  What really took time was the granary itself as the boards had to be lined up and the fading matched to the local areas I was cloning.

The original image was 12x18 inches at 300 dpi, so the detail was incredible.  I used photoshop CS6 to do the job, but any of the Elements programs or the newer CC series would have done the same thing.  I prefer to use the clone tool instead of the heal tool because I find it does a better job, especially when it comes to precision.  Once you figure out the idiosyncrasies of the tool options, the process becomes straight forward.

I photographed this during our summer holiday this year.  Creston was quite beautiful and I especially enjoyed the bird sanctuary.  The blog I posted earlier about my book was written partly there, and the picture of the kingbirds was taken at the preserve.

Using fill flash

Umbrella man - with and without fill flash

If you look at the two pictures above, you may initially think they are exactly the same.  Yet, upon closer inspection, differences begin to emerge.  Differences in shadow, colour, white balance, and details are clearly visible.  So, why the difference?

One of the best tools you can have in your photographic arsenal is a good flash.  The image on the left (before) did not use a flash, the one on the right did.  There was certainly enough light present to take the photo without the use of a tripod, extreme ISO values, or flash, so why was one used?  The answer is in the details.

Fill flash is defined as the use of a flash to fill in shadowed areas, usually on the subject, which otherwise would appear dark and lack significant detail.  The shadows exist because light cannot adequately get to those parts of the image.  Flash then fills those shadows, providing enough light to ensure that image detail and colour all are expressed.

When do you use fill flash?  The need arises when your subject is underlit because of background lighting (backlit situations) or if light is being blocked from part of the subject.  In this case the sun is coming from behind the subject (notice direction of shadow) and the umbrella is also blocking any ambient light that otherwise might be available.  Flash provides that extra light.

Notice as well how the colour is different - look at the colour of the brick work and the wall in behind the statue.  The camera's white balance has been altered and the second image is far better than the first.

There are a lot of little tips and tricks to using fill flash; you can do it with the flash built into a camera but are typically severely limited by distance.  Generally though, it is a simple matter of turning your flash on even though there is enough light to take a photo without it.

Here is an idea - which is the main reason why I do these blogs - take two photos, one without flash and one with.  You will see that it is a simple matter of just popping it up.  An external flash unit will do a better job, but you may be able to see the difference with a built in one.  Push play and have a look; zoom in - did it make a difference.  Sometimes it will, other times not so much.  But the more you do it, the more you will see what works and what doesn't, and your photographs will improve in the process.