Week 9

Focal Length

The focal length of a lens is the distance usually in mm from the lens to the ccd sensor when the lens is focused on an object at infinity. 

So what is the use of knowing this?  Well, If we can understand  focal length, it is one more tool to help us take better photographs.  Let’s start with what a standard lens is.  

Standard Lens

A standard lens gives a view similar to the human eye, about 53 degrees,  its focal length  is equal to the diagonal size of the sensor.  Unfortunately all cameras don’t have the same size sensor.  So there can be a lot to remember. 


For a 35mm   film   camera    the standard lens is 52mm   

For DSLRs owned by everyone in the class the  standard lens is 35mm  

For other  more expensive DSLRs the  standard lens is 50mm  


Bridges and some compacts   the  standard lens is 8mm or 9mm 

Wide Angle Lens

As we reduce the focal length below the standard size, we begin to see more of the scene, and objects appear further away.  This is similar to to what happens when we look in a wing mirror fitted to some cars,  we see more of the road to the rear and side, but we can be fooled into thinking a car approaching is further away.

There is an advantage to fitting more into the frame, for example it can be ideal for landscape shots and can give dramatic views of inside buildings,  but there is  the disadvantage that the lower we take the focal length, the more distortion will be  introduced.

Take care when using a wide angle setting and you’re up close to your subject, you can end up with some strange results.  Of course you can always use the distortion for effect. 



Photo by Brittney Bush

Photo by Childish Dave

Click here to see more examples of Wide-Angle Distortion

For DSLRs  Wide-angle range is 35mm -and below

Prime lens

You may see the term prime lens used,  this refers to a fixed focal length lens, that does not zoom.   They usually consist of  better quality elements that allow  wider apertures to be used.  We discussed the advantage of the prime lens that I have as an example.
It's a 35mm focal length, but allows 21/2  stops wider aperture than my 18-55 zoom lens.

In practical terms that allows me to use the camera indoors without a flash without worrying about camera shake.   It is the difference between being forced to use  a shutter speed of 1/20  and 1/120, bearing in mind that I've said all along that any shot below 1/50 can't be hand held.

Telephoto lens 

As we increase the  focal length, objects begin to appear closer, there is a lessening of the angle of view and a flattening effect takes place.

Zoom lenses gives the advantage of flexibility, but at the expense of quality and speed.

While looking for a shot to demonstrate the compression that takes place when using a telephoto lens I found this excellent example series.  And later even discovered an accompanying video.

For DSLR  Telephoto range is 35mm -and above

How the shots were done - youtube video

Exposure Compensation

 

I asked you to find the above symbol on a button your cameras.  If I'm not mistaken, all of the cameras owned by everyone in the group has such a button. 

Set you camera mode to anything except Auto or Manual (try Aperture or Portrait mode) Press the

 Exposure Compensation button and you should see a scale appear.  

use the Left / Right buttons or Dial  to adjust the pointer as far to the minus side as possible.

Now take a photo.  Adjust the scale again back to the centre and take another shot.

Take another photo of the same subject.  Again adjust the pointer to the highest setting and take another photo.  When you look back at the three shots you have just taken, you will see that the first is considerably darker than the last.  The last one will probably be far too bright, but I hope that this will be a valuable tool in adjusting the exposure of your camera in certain situations.

The example I would use is where Joyce complained that when she takes a photo of stained glass windows in a church, the colours look washed out. So by adjusting the exposure compensation down we can regain the saturation in the colours of the window.  Remember to turn the flash off in such a situation though.

We also touched again on the subject of portrait photography.

Although we have tried out some portrait photography in the other classrooms in previous weeks,  

I haven't really set it as a task for "homework"  So I suggested that you try some photographs of people. You don't necessarily have to know the people, in some respects it can be easier if you do not know your subjects that well, but do talk to the person your shooting, ask a few open questions that will give them a chance to tell you something about themselves. 

Props are good

If your subject is involved in an activity, holding something or wearing something unusual this can help to tell a story or create questions in the viewer's mind.  It's only limited by your imagination.

Focus

To refer back to something that we mentioned a few  weeks ago, what is your point of interest?  If your photo contains a face, it will be the eyes of the subject that the viewer will look at first.  Ensure it is the eyes that are in focus, not the tip of the nose.

It need not contain a face

It does not  necessarily need to contain the face of the person,  hands, feet and other parts can make interesting subjects. 

Watch the background

Apart from the really obvious things like lamposts growing out of your subjects head, at the background for things that distract from the subject.  One subtle example is when a horizontal line such as the horizon cuts through the head of the subject.

A recent example I came across was on this website of a prominent solicitor. 

http://www.marilynstowe.co.uk/about/

Is she wearing a backpack?

See you next week with your people photos.......

Week 8

We spent some time this week visiting other classes, so we did not really cover any new material.

I encourage the use of natural light whenever possible, but sometimes I know we will need to resort to the use of flash.  

Remember.  to avoid having to use flash, follow this procedure.

Aperture  -  Wide as possible (so the smallest number)

Shutter speed. - Low as you can manage without camera shake, this will be down to the individual, but anything less than 1/50 will be risky.

ISO  -  As high as you need to go once the other two are set.

I'm hoping that following our visits to other classes, we'll have some shots that we can use for advertising material next year.

Week 7

This week we looked at photographing people.  This is an area that I probably feel the least comfortable with, but there are times when we are at an event and we need to be able to step up to the mark and deliver a photograph that will commemorate the occasion.

 

If you're indoors I would discourage the use of “on-camera” flash whenever you can get away with it.  The problem with “on-camera” flash is that  the light is harsh, direct and always comes from the direction of the camera so you will not get any shadow  and you will most likely create red-eye.  It is also impossible to remain discreet when using a flash.

If you're indoors I would recommend disabling the flash, setting the aperture as wide as possible, the shutter speed as slow as possible and the ISO as high as necessary.  Don’t forget the white balance.

Portraits
You will need as much light as possible so get close to your light source.  A window during the day is a great light source, but preferably not in direct sunlight.  A reflector can be used to fill in the shadows if necessary.  You do not need to go out and buy a fancy reflector a piece of white card, paper  or cloth  will do the job.  One tip someone mentioned was to use a fold-up windscreen heat reflector.

We want people to relax when having their photograph taken, so we need to be relaxed and confident ourselves.  It will be difficult to relax if we are getting stressed about which setting the camera should be on , so take time to know your equipment.  Practice changing settings while you have time to yourself, but also practice taking photos of people  in everyday situations. When the time comes at that special occasion, you will know the settings to use for an outstanding photo.

It may sound clichéd, but talking to and interacting with your subject will help them relax, take some time to get to know the person.  This is a really important point when taking photos of children.  It doesn’t have to be a half hour in-depth discussion, just ask two or three questions in a relaxed manner that allows them to talk a little about themselves.

Context
One particular aspect of portrait work is to place your subject in a situation where they are doing something or obviously in a situation where they have been taking part in an activity.  To this end  we spent a little time visiting some of the other classes and managed to get some interesting shots of cake makers, guitarists, artists, ICTers and spanish learners.  


Here's a link to my efforts ....    http://flickr.com/gp/timbalimber/278LZF/

No Classes on June 7th due to school half-term holiday.