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This page contains a selection of technical tips and advice, contributed or forwarded by individual members. They are presented here in good faith but are not necessarily endorsed by SeniorNet Eastern Bays Inc. All new material, corrections and refinements are very welcome.
For those of us who can remember their first transistor radio and remember looking inside at the printed circuit boards and transistors, the world has changed in a breathtaking way.
Computers are complex switching devices full of transistors, each one operating like the light switch on the wall, Off or On.
Whereas our early transistor radios used about six or eight transistors that were about the size of the rubber eraser on the end of a pencil and had three wires protruding from them, modern computers use a massive amount of transistors, about 9,437,184 in an LCD computer monitor screen, three transistors for each of the three colours in each pixel.
Some years ago I read that if we laid 1500 transistors side by side they would be the thickness of a human hair.
I couldn't really imagine that, let alone that by now the number would be several times larger.
So, how does a transistor work?
In the diagram below, the electrical current flows through the blue wire in the direction of the arrow.
The red control element controls the flow of the current.
When there is a voltage applied to the control element the current flows.
When there is no voltage applied to the control element, no current flows.
In this way the transistor switches On and Off as commanded.
How does it know when to switch On and Off? The software program tells it when.
The program consists of the digital commands as below.
The program starts at the first command and continues from left to right down through the program.
0010111100010011001110001010001100011010101000010100001000001101000011101101011001
… and so on, for an awful lot of commands.
Each 1 tells the computer to close that switch and each 0 tells it to open that switch.
Each digit is called a Bit of information and eight digits is called a Byte.
One thousand bytes equals a Kilobyte, a million bytes equals a Megabyte, one thousand million bytes equals a Gigabyte and a million, million bytes equals a Terabyte.
How does the computer turn the digital commands to the text and pictures that we see on the monitor?
Enter Mr Bill Gates who, in the early days of the desktop computer sold IBM the DOS operating system.
He didn't invent it but that early sale began his rise to fortune.
“Now,” as the Microsoft instructional videos say, “you know all about computers.”
Buy yourself one or more Dry-Bags, aka Dri-Paks, aka desiccant bags from any good photography supplier. Also buy a sealed plastic box, big enough for your camera and any other small accessories. Take your camera out of its case - make it as naked as possible - and place it, the accessories and the Dry-Bag(s) in the plastic box. Make sure of the seal. The desiccant will need to be recharged every week or so. You can do this by either placing it in the hot water cupboard overnight or in the warming drawer of the oven (read the instructions with the Dry Bags).
That advice could apply equally to any optical or electronic device that's small enough: humidity, mould and mildew are the biggest enemies of intricate and electronic devices. The worst thing you can do with any of them is put them damp into their cases and then into a cupboard where no dry air can circulate. Obviously, if you have good air conditioning, you could just leave the (naked) camera on an open shelf (but keep the lens cap on). Yes, I guess that makes it easy for burglars but, since you always take your camera with you in case of that shot-of-a-lifetime (don't you?), that shouldn't matter!
Q: Can any digital camera be used as a webcam or does one have to buy a dedicated webcam from someone such as Dick Smith?
A: Many digital cameras can double as video cameras, at least for short clips, but most cannot double as web cams. Web cams are getting cheaper. Off hand, I'm not sure what is the best buy at the moment but I see that one of Dick Smith's own brands has a built-in microphone as well for $37.87, which should be adequate for video phone, chat and similar. The more fancy ones can perhaps double as low-end video cameras especially if they are used with a notebook/laptop. Others still are tailored for video surveillance and usually come bundled with corresponding software.
No doubt you have now amassed a vast collection of digital photos. Many of the scenic ones may be too wide angle and not level with the horizon, so the simplest enhancement you can do is to use the Photoshop Cropping and Straightening tool. With an aggressive crop, you may end up with a photo which is half as wide and half as high. That means you would be down to one quarter the number of pixels - your typical 4 Megapixel image would become a 1 Megapixel one. That's good enough for small prints in an album but not quite good enough you want to make a large print.
That's why I have an 8 Megapixel camera myself. Don't forget that the now "old" 35mm film or transparency has an equivalent resolution of 12 Megapixels. The old medium format films (60mm) would have about 35 Megapixels which is why prints from them can be still blown right up to adorn galleries to this day.
If your photo comes directly from the Internet, it will probably arrive with a built-in resolution of 72 pixels per inch. That's the standard for web pages and Explorer and Outlook Express will use this unless otherwise advised.
But, if the photo was taken by a digital camera with, say, a 300 pixels per inch setting, a simple program like Outlook Express will blow the image up by a factor of four (300/72) in both height and width.
Most programs actually designed to display images conveniently for you (such as Picassa) will automatically fit them neatly to your screen size (unless otherwise instructed). Likewise, most programs that print photos for you will give you the option of scaling them up or down to fit the paper you place in the printer (but you must make sure to "tell" the printer that actual paper size). The printer can typically show you a preview so you can check the effects of taking that and other options before the final printing.
But, if you specifically want to resize a given photograph to a definite number of inches/cm/mm of height and width, open it in Photoshop and then click on Image->Image Size ... the Image Size box will open. Now this is where you need to be careful. First, uncheck the "Resample Image" option (if it was ticked) but make sure the "Constrain Proportions" option IS checked/ticked. Now, in either the height or the width boxes (but not both), enter the height or width to which you want to resize your image. You may want to change the units on the drop-down menu to inches, cm or mm at the same time.
Note that, when you change the width, the height and the resolution automatically change in proportion. So if your picture was 12 inches wide by 8 inches high with a 150 pixels/inch resolution and you change the width to 6 inches, the height would automatically change to 4 inches and the resolution would automatically change to 300 pixels/inch. Both before and after, your image will have the SAME number of pixels. If those measurements are exactly what you want you can click OK at this point.
What if the resolution is not enough? Well, in principle, you can re-check the Resample Image box, enter the desired resolution and then click OK, BUT - beware that re sampling the image (especially upwards) is a calculation only - its the software's best guess at what the missing pixels should be. You may be better off accepting a lower resolution rather than risk having odd artifacts appearing in your picture. Although 300 pixels/inch is said to be the ideal resolution for high quality printing a (full sized) photo, 200 is adequate and 150 is still
Q: I am having problems with Adobe Photoshop. Every time I try to enlarge a picture in My Pictures it grabs it. How can I stop everything defaulting to Photoshop?
A: Find a typical picture (probably a JPEG). Right click it , choose "Open With" ... then select "Choose Program" (at the bottom). Then click the program other than Photoshop (e.g. Windows Picture and Fax viewer) you want to use. Before you click OK, tick the box which says "Always use the selected program to open this kind of file".
Any file type can be associated with a particular program using this method
Included in XP, Movie Maker is supposed to be in the Accessories Folder, i.e.:
"Click Start, point to All Programs, point to Accessories, and then click Windows Movie Maker"
Well, it wasn't there in my setup! I found it in the C:Program Files/Movie Maker folder. Its "moviemk.exe" to be exact and you may need to use the Start->Search facility to find it on your own setup. Having found it, you might then want to right click on it, take the "Create Shortcut" option and then click and drag that shortcut onto your desktop.
Adobe's Portable Document Format is explained in detail in this article from the Wikipedia. Because PDF files don't encode information specific to the software, hardware, or operating system used to create or view them, PDF is an ideal universal format. It is used to convert documents from Word, Excel, Publisher, Photoshop, PowerPoint, Illustrator and many similar packages
Many free programs can read and display PDF documents, but the one most of us probably have is Adobe Reader.
You probably have at least an early version of it, which came bundled with either your new computer or as part of a software package you later bought.
Recent versions of Adobe Reader have amazing extra features, including the ability to display 3D representations.
See their FAQ.
You can download the latest version by first clicking here (and the link also offers two other (free) Adobe products you can also optionally download while you are about it).
Adobe, however, do not give away the software which can create PDF documents.
They do offer a range of products whose feature lists increase with price.
The most modest of these (Acrobat 7.0 Elements) is still about $100, depending on the way you might buy it.
However, there are several free PDF creation tools available from third parties, which offer enough features to satisfy most of us home users.
The one I've just test driven is PrimoPDF.
If you visit this page, you can read about it and then click on the download button.
As always, read the manual (which is, of course, in PDF format!).
Let's say you create or update a Word document. As usual, save the master copy in Word (.doc) format and print it (still as a Word document) on your standard printer. Now start to "print" it again, by going to File->Print. The print box will appear, as before. Now pause: In the first window will be the name of the printer you just used. But click on the little, upside-down, solid triangle on the right side of this window and you'll see a list of all other print-like devices you could use. One might well be your fax, but the one you want is the "printer" named "PrimoPDF". Select that and click on "OK". Up will pop the PrimoPDF window. On "PDF settings", select the Print option, then go to the "Save As" window, click on the three little dots on the right and browse your way to the folder you want your new PDF file to be written to (the default folder for PDF's probably won't be the same one as your current Word document folder but next time it should "remember" and save you the journey). After you press OK, your Adobe Reader will proudly display your new PDF document. You can now send it (by email enclosure) to anyone, anywhere to be printed or displayed on whatever printer or screen they may have. All they need to have is their own copy of Adobe Reader.
PrimoPDF has many more options and features than the above might indicate so, again, re-visit their site and re-read your manual
For those of you with the CS or CS2 version of Photoshop and who have an image with shadows that are too dark and/or highlights that are too bright, check out the Shadow Highlight option:
Go to the Image Menu->Adjustment->Shadow Highlight
Play with all the knobs for a few minutes and then read the help file(!)
If the program or package came with its own de-installation program on the original CD you should insert that CD and follow the instructions.
Otherwise, you should try the standard method for de-installing any program:
Close all programs.
Click Start - Control Panel - Add or Remove Programs.
Wait for the list of installed programs to populate and then scroll down and select the program.
Click on the Remove option.
Restart the computer
Verify that it has, in fact, gone, including any shortcuts.
Some de-installations still leave directories behind them - check that they do not contain important data and then remove them too.
