Using a scanner, a digital camera and Photoshop
Spring 2005
Induction and introduction
Show the class this page and give a
brief overview of the course.
Discuss and negotiate any changes that members might appreciate.
Why bother doing this course?
Graphics are becoming easier to distribute and print, with the accessibility
of cameras and scanners there has never been a better time to utilise
images within our own daily lives. You may want to make a notice, enhance
a document for the Internet, a presentation or for printing, or just to
clean up or manipulate photographs, the list is probably endless (even
if I can't think of any other examples right now). Being able to manipulate
graphical images is the key to turning humdrum attempts at being creative
in to unique works of art.
While scanning images is thought of as a simple task the benefits of
looking deeper into this process will result in high quality and appropriate
raw materials for the task in hand.
A digital camera is also used to create an image however the process
is far more complicated than scanning and is generally avoided because
it seems such an art in itself. Often people hope to utilise software
packages to make up for bad photography. In this course we shall be introduced
to the basic principles of photography, right from what to look for when
getting a digital camera to how to take pictures and then what to do with
them, including enhancement and presentation.
Throughout the course we shall be using a piece of software to manipulate
images, this application is called "Photoshop". Photoshop is
the industry standard program for graphical manipulation and it's also
one of the the most expensive. However it is possible to buy cheaper versions,
such as "photoshop elements", "photoshop lite" and
"trial" versions can be obtained for free from the adobe
web site.
In lesson 1 we shall be looking at what to consider when buying
a digital camera. We'll also take a brief look at photoshop, how to load
it, its main components, making a new file, saving it, basic drawing,
and changing colours. But first it's worth getting your head around image
files.
Digital image files
What is a digital image?
Further reading http://www.photocollege.co.uk/scentre/bb/bb1.html
What types of images exist (animations, photos, diagrams, logos and many
others)?
Further reading http://www.lib.uconn.edu/~habbey/images/formats.htm
Why are there different file types?
Further reading http://www.webcom.com/help/webcommerce/images.shtml
What are the main file types and what are the advantages of them?
Further reading http://netghost.narod.ru/gff/graphics/book/ch01_04.htm
or http://mrs.umn.edu/~pam/IT/compression.html
Talk about compression
Further reading http://www.shortcourses.com/how/files/files.htm
This is a must!!
Discuss final output and its effect on resolution size and file type.
What to consider when buying a digital camera
First of all don't bother asking a sales assistant about buying a camera,
it's like asking a waiter what dish tastes best, they'll probably tell
you one of two things, either what they like or what they want to sell
you. So who can you listen to, the answer is your self, however that's
only when you know what to consider. In this section I'll try to cover
what aspects of a camera are important and why.
There is no perfect camera, there will always be an element of compromise,
so just like a marriage finding a balance between comfort and what fulfils
one's requirements is what one will most likely decide on. Therefore the
first question to ask is what are your requirements?
1 Do you want to use your camera just for snaps, and have very little
regard for controlling how your photos look?
If the answer to this is yes then you probably wouldn't be doing this
course, no matter how apathetic a person is when it comes to how their
photos look it's still annoying to have pictures that are blurry, so going
for the lowest common denominator when it comes to cameras rarely pays
off. At the moment many mobile phones take pictures, however the quality
of images they capture is generally low. Even when they of reasonable
quality the lack of flash and a zoom can be frustrating, but for convenience
and fun these "cameras" seem to have found a niche, even if
generally speaking the images they create are unusable for anything other
than a momento of a moment.
2 Is image quality essential, and if so will your images be printed
or appear on a screen?
Most people say that image quality is important but the pay of for image
quality tends to be greater cost so this need for quality tends to be
undermined by our budgets. There is another way to look at this though
and this is that image quality is actually measured in more ways than,
excuse the pun, meets the eye. Most people understand image quality to
be mainly related to resolution, but this isn't always true. Depending
on one's needs resolution normally comes second to image sharpness and
image sharpness is mainly effected by lens quality. If you speak to a
sales person they will throw the words "mega pixels" at you
and very rarely touch on lens quality, but the pictures below demonstrate
this point. The top shot has a bit more clarity t it and the camera has
allowed the photographer to decide on that gets focused on, (choosing
the depth of field), whereas the other photograph has a slightly fuzzy
feeling about it and allowed the photographer very little control.


Although lens quality is of paramount importance, being
able to control how light comes in to a camera is almost just as important.
By controlling how long the amount of time light is allowed to come through
a lens, (shutter speed), and how big the hole that light comes through,
(the aperture size) pictures can appear very differently.
By simply making the aperture smaller the contrast is increased,
as is the "depth of field" - the depth of area that's in focus.
The pictures below shows one picture taken using an automatic setting
and the next one shows the effect of decreasing the size of the aperture.

This picture seems quite bland compared to the one below

This picture has an almost classic painting effect merely by limiting
the amount of light by making the aperture smaller.
Another important aspect of picture quality is how close
to the original colours the output colours are.
It is also worth considering if you're going to be printing
large version of your pictures whether the outer edges of your photos
seem blurred or distorted, low quality lenses often have this effect.
It's generally worth paying attention to how a lens looks as it'll probably
be a good indication of it's quality. A small lens is morel likely to
be of a lower quality than a large one, but not always so.

Small lens (Yuk Yuk)

Big lens (Mmmmmmmmm lovely!!!)
So to recap picture quality is effected by lens quality
(sharpness, speed, and lack of distortion), colour accuracy, and manual
override functions, and finally mega-pixels. Mega pixels is a term that's
currently used to denote how many dots are used to make up a picture.
The more dots in theory the better quality the image but as we have said
other factors need to be considered. Who cares how many pixels you have
if the image is blurred, distorted, and the colours look wrong. The main
point of having lots of mega pixels is that if the rest of the formulae
is good enough the effect will be felt mostly when it comes to printing.
A good 5 mega pixel camera will produce a sharp image even when printed
at A3, whereas a 2 mega pixel print will start to look "grainy"
at anything larger than A5.
So are you bothered about picture quality now you have a
better understanding of what it means? The answer probably should be "Yes
but only to a point", exactly where this point lies will be to do
with your own individual needs.
3 Will your camera need to be used covertly or do you need to look like
a professional?
While it's funny to think like this I meant that question to have several
meanings, the first is sometimes it's important to be unobtrusive, not
just in terms of getting candid shots, but also attracting the attention
of thieves lets say when traveling may be a kin to wearing expensive jewellery
in an inappropriate place.
The opposite may also be true, turning up to do someone's wedding photos
with a disposable camera may not create the right impression.
However the photographer who took photos at the Michael Douglas and Catherine
Zeta Jones wedding for the unsolicited magazine probably made the right
decision not to take a large format camera.
4 If you need to control how your camera takes pictures then what camera
feels comfortable and easy to manipulate?
Attention to ergonomics doesn't always mean a camera will work for you.
It's important to be able to adjust settings, see through the viewfinder
easily, adjust the focus of the viewfinder if you have long or short eyesight.
The camera should feel comfortable to hold, well balanced, and all the
controls should be intuitively placed and easily reached. There's no point
having a camera that feels wrong because you will continually miss "picture
opportunities". Many cameras say they offer over ride features however
in order to get to them the user has to scroll through many menus to get
to the controls. The answer is to get a camera that has well placed buttons
to the main functions, such as flash, aperture, shutter speed, macro,
manual focus, "lock down", white balance, easy review functions.
5 Video functions
Many digital still cameras have the ability to record video and sound.
If you'd like this facility check to see if the camera you're looking
at not only is able to record video but can it record sound too, also
how long can you video for and if so at what resolution and frame rate.
Having the ability to record video can be useful for capturing special
moments without having to cart around a video camcorder, admittedly the
quality won't be comparable but for most people it's good enough as memory
jolter.
6 Storage and data transfer
How many pictures can a camera store, what storage medium does it use,
and how fast can pictures be copied from the camera to a computer?
The question of how many pictures can be stored is answered by understanding
two variables: Picture file type / size and memory the capacity of the
storage medium inside the camera. Pictures can be taken using different
resolutions and then saved using different file types. A high quality
TIFF version of a picture may be 10 Mb in size whereas the same resolution
picture saved as a jpg may only be 1 Mb. If your storage medium has a
limit of 128 MB then you'll be able to store 12 TIFF files or 128 Jpg.
Why choose TIFF then, well the answer's quality, a TIFF image may be slightly
better quality than a JPG and if you're doing a professional shoot then
you may be required to take the best quality pictures you can. In terms
of what this means as to what type of storage medium should you aim to
go for, then for most people it doesn't matter, but if you are likely
to need to be able to take many pictures without copying to a computer
in between shots then you need either a very large capacity memory card
such as a 2Gb Memory stick Pro, or lots of cheaper cards that can be replaced
when one gets full up. Whatever camera you go for you're not likely to
find it comes with an adequate memory card, and most people tend to end
up purchasing at least a 64 MB card and preferably a 128 Mb one so they
can take around 80 high quality Jpg images in one go before having to
transfer the images to a computer. Most new cameras transfer images to
a computer either by using a USB or Firewire connection, for most people
this method is fast enough, however if you're considering buying an older
camera that uses a serial connection then be warned you may have to wait
up to an hour for pictures to be transferred that would take a couple
of minutes on a new camera. One way around this problem is to buy a memory
card reader that attaches to the computer. You take the memory card out
of the camera and stick it in the card reader. You then copy or move the
images to your computers hard disk. This is the way I work, my computer
has a card reader built into it so rather than plug my camera in to my
computer I just take the memory card out of the camera and pop it in to
a slot on the front of my PC.
Confused?
If this hasn't confused you enough or not made you feel utterly sick
about the purchase you just made you may find the following web sites
of interest.
To check prices try www.kelkoo.co.uk
I strongly recommend www.steves-digicams.com
however it's worth getting further opinions from the following:
http://www.dpreview.com/
http://www.imaging-resource.com/
http://www.photo.net/
http://www.betterphoto.com/home.asp
http://www.digitalcamera-hq.com/
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