Nowadays most pictures inside a PC come from somebody's digital camera.
But in cabinets and boxes you have old pictures saved on film and paper!
Here is some basic knowledge on photo handling in a PC and on scanning photos from paper and film and also some basic things about scanners and their resolution.
Do not forget to backup your pictures to a CD. Your hard disk may fail or its content may be destroyed by a virus program slipping into your PC.
But how many pictures can you actually store on a CD? A quite common resolution for a PC monitor screen is 1024 by 768 points. That will make 786.432 different points on the screen. A color picture requires three bytes (of eight bits each) for every point on the screen. If a photo covers the whole screen, you will ned 2.4 MB for that photo! Then there cannot be room for more than 270 photos on a 650 MB CD!? Eh?
How come? By saving your photos in a compressed format like .JPG, you can compress most pictures to the 10th or 20th part of their original size without seeing any difference compared to the original pictures. As a consequence you can store some 2000 or 6000 photos on a single CD! That means: On one single CD you can send ALL your holiday, Christmas and children photos you ever had to your mum or to your mother-in-law!
One of the most well known programs for photo editing is Adobe Photoshop. This is a very good program, but it is also very expensive. But there are several much less expensive alternatives, like Paint Shop Pro, Adobe Photoshop Elements and ThumbsPlus where you will find tools for picture editing and also tools for sorting and keeping order among your pictures.
A mnemonic rule: RGB versus CMY
Sometimes it can be very difficult to adjust the colors in a photo because
there are different type of faults in different parts of the photo.
But "practice makes perfect".
It is more fun to work with a large screen than with a small one.
Some years ago only very big and clumsy screens with cathode ray tubes (CRT) were used for PC:s.
Today the modern LCD screens are flat, slim and light and do not occupy much space on your desktop.
But an old CRT-screen is often better than a bad LCD-screen. This is because the
"viewing angle" is higher for the CRT-screen.
With an old LCD screen the picture looks nice only when you sit exactly in front of the screen.
If there are several people looking at the screen, then a CRT screen is usually superiour to an
old LCD screen.
The same photo may look quite different depending on how you have adjusted your screen. If you have copied a couple of photos to a CD and then look at them in the home of a friend, you may find that they all look too dark or too light on his PC monitor. To avoid such a surprise you should calibrate your screen in some way. There is a facility in Photoshop for calibrating your screen (Help/Color Management).
Photos and other pictures can be read with a device called a SCANNER which can be connected
to your PC.
Paper print photos are scanned into the PC from a so called flatbed scanner which is quite inexpensive. It costs from 100 US dollars and up.
Paper prints in color are usually of
a very low quality compared to what is hidden in your film negatives. Therefore it is always
better to scan from a negative or diapositive (i.e. film) than from paper.
Diapositives and negatives are named film contrary to paper. The most common type of film today is 35 mm wide and used for pictures with a size of 24*36 mm (1 by 1.5 inch). Old cameras were loaded with wider rolls than that. In earlier times they used photografic glass plates.
There are a lot of film formats larger than the 35 mm wide film. As an amateur I run accross them when taking care of old negatives like 60*60 mm, 60*90 mm, and 70*110 mm.
To scan such film you need a flatbed scanner like that used for paper prints, but the scanner should be equipped with a transparency adapter. A transparency adapter is a special lamp used to throw light through the film.
You can use a special 35 mm film scanner for scanning common 24*36 mm diapositives or negatives. Such a scanner costs from 500 US dollars. Though you may as well use a flatbed scanner with a transparency unit for scanning 35 mm film!
Some people say that a flatbed scanner makes inferior pictures compared to what you get from a "real" 35 mm scanner. But look at the test pictures below!
The original diapositive picture has the size 24*36 mm. It shows the "Schiffshebewerk Scharnebeck" 1978, a type of lock at the Elbeseitenkanal in the neighbourhood of Hamburg. Here ships are hoisted upwards or downwards in a huge bath tub.
The picture and details from it are shown in columns, each scanned with a different scanner.
1: Hewlett-Packard Scanjet IVc flatbed scanner from 1996
2: Hewlett-Packard HP7400C flatbed scanner from 2002,
3: Epson Perfection 2580 Photo from 2005
4: Epson Expression 1680 Pro from 2002
5: Nikon LS-2000 film scanner from 1999.
At the top you can see small versions of the scanned pictures. The colours differ slightly. The Epson 1680 scanner was color calibrated, so probably its scan has the correct colours.
The scan with the old 600 dpi scanner is shown to demonstrate the shift in technology over time. See also the picture at the end of this section!
The price for a good scanner has gone down drastically over the years. The Epson Perfection 2580 bought in 2005 cost only some 10% of the price of the other scanners bought in previous years.
Note: Some scanners have a mechanism for automatic removal of shadows coming from dust or from spots of dirt. (That dust removal mechanism does not work for black and white negatives and partly not for Kodachrome film.) This is a very labour-saving feature, though it gives you a slight reduction of the sharpness. When used with the Epson 2580 scanner I found it to remove too much of details for my taste.
Comparing resolution of two contemporary flatbed scanners from 2002
From the pictures above it is apparent that the Epson Expression 1680 Pro has a higher actual resolution than the HP7400C. The technical specifications for dots per inch tell another story... - our copy of the HP7400C does not have the specified resolution!
The marketplace is a djungle where many manufacturers outbid each other in specified but not always attained performances!
Various scanner features
New scanner models are entering the market all the time. Here are examples of some features to consider when you look at a new scanner. Probably you do not contemplate to buy one of the old scanners mentioned here, but consider the features and their limitations.
The transparency adapter
The HP 7400C transparency adapter can handle pictures no larger than 5 * 5 inches.
The Epson Perfection 2580 Photo can only handle 35 mm film. No old medium format negatives with this scanner!
The transparency adapter of the Epson Expression 1680 Pro covers the whole glass surface of the scanner. This is an advantage if you want to scan large overhead pictures or if you want to scan old glass plates. The enclosed SilverFast Ai5 program gives you a quick and reliable color calibration. The enclosed film holder holds the film a small distance above the scanner glass surface. This will keep Newton rings away from your scanned pictures without loosing sharpness. (A special mechanism is used to focus at a level above the scanner glass.) The mecanical construction seems to be more robust than for many other scanners.
Speed of scanning
When selecting a scanner: Do check the scanning speed in both low and high resolution mode. According to a test in the Swedish magazine "Mikrodatorn" (3/2002) the HP 7400C scanner mentioned above scans three times faster than the then comparable scanner Epson Perfection 2450 Photo when scanning 35 mm diapositive film.
There is a lot of other brand of scanners. As said above: The marketplace is a djungle where many manufacturers outbid each other in specified but not always attained performances.
When comparing pictures be aware of the effect from so called "unsharpening" tools used within scanners and within photo editors. These tools make a photo look much sharper than it looked when originally scanned. Though comparing a very sharpened photo from one scanner with a not so much sharpened photo from another scanner may lead you to false conclusions about the quality of the scanners.
So an advice today (:-)) would be: Before using a picture for a comparison between two scanners,
use your photo editor to make both scanned pictures look as sharp and nice as possible.
Because if one of the scanner manufacturers is using more sharpening inside his scanner than the other does,
then comparing the original scans would be unfair.
So better try to use as much sharpening as desirable before comparing. To avoid fooling yourself!
Noise: You should also look for noise in the picture. Noise manifests itself as areas which should be plain and uniform but which look grainy or streaky. It comes from the inability of the scanner to differentiate between slight differences in the picture. Typically it occurs in very black areas. Normally this does not matter much when you are scanning a positive. But with a negative, the very black areas will be converted to light areas when you make your positive. Look at this example from a photo taken against the sun, to see what I mean.
There are many more very expensive film scanners with higher resolution. There is also something awfully expensive named "drum scanners" which are used within the advertising industry. There, people often need very enlarged pictures and want to avoid having details looking blurred when you look at the blown up printed picture from a near by position.
A rule of thumb when scanning paper prints: Do not use a resolution higher than 300 dpi (dots per inch). Sometimes you may get a better result with a higher dpi number if you have a very high quality black and white photo, but this is an exception.
Good tips about scanning can be found at www.scantips.com
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