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How to get photographs to us
First, if you are sending us photographs for display on our Secondhand page, the ideal is listed below. If you can do any of the things on the list it will save us a job and a little time. The steps below will not only ensure that you are emailing the smallest possible file to us, but the more 'right' your picture is, the quicker we can get it on the web!
- 'Crop' the picture to remove unnecessary information from around the item you are selling
- Reduce the picture to 500 pixels wide (x whatever tall. Don't squash or stretch the picture though!)
- If necessary, reduce the picture resolution to 72 dots per inch (dpi)
- Save in JPG/JPEG format at 50% compression factor
- Avoid sending pictures embedded in Word or other documents*
- From the end of June 2005, we can only accept one picture per advert.
* Embedding pictures in Word documents adds complication and makes your attachment much larger than it need be. Simply attach the picture that you would have embedded instead.
General
We can make use of electronic picture files (from a digital camera, scanner or computer), or as ordinary prints/slides/negatives.
Electronic
We can read most computer graphic formats (JPG, GIF, PNG, TIF, etc), but if you are emailing files to us, be aware that it could take a long time if you send large photographs. If you have access to graphics software, do the following to reduce file sizes:
- Cut or 'crop' any uninteresting parts from edges of the picture
- Reduce the 'resolution' of the picture to 72 dots per inch (dpi)
- Make sure the picture is in 24 bit 'RGB' format
- Save the picture in 'JPEG' format at 50% compression factor, or in 'compressed TIF' format
- Reduce the size of the picture to around 600 x 400 pixels
If you do all of the above, you should end up with a file size of around 50-100 KB.
Prints, slides, negatives
We can scan photographic prints up to A4 and 35 mm slides or negatives, and we will return your pictures. If you are with McGahan Lees, you can probably pass them to us via somebody in class -- ask a 'Friends' committee member. You can also send them by post providing you package them well, and include a protective stamped-addressed envelope for postal returns. Send them to:
The Webmaster
360 Ongar Road
Brentwood, Essex
CM15 9JH, England
Don't forget to put a note of who you are in with any pictures you send to us!
More on pictures
If computer graphics are a bit of a mystery, you might like to learn a bit more about them. The stuff below won't get you into the business, but it may answer one or two of those niggling questions.
First, all of what you see on your computer screen is made up of tiny dots called 'pixels' (picture elements). If you counted the dots in a square inch of your screen, you would see there are 72 rows of 72 dots, so each square inch of your computer screen is made up of 5184 individual coloured dots.
Some screens look sharper than others, but that's because the edges of the pixels are closer together -- there are still only 72 dots per inch (usually abbreviated to dpi). A larger screen will make what you see clearer, but you will never get anything like 'photographic quality' on a computer -- by way of a contrast, magazine pictures are typically printed at 2400 dpi or greater.
The 'sharpness' of a picture -- whether on a computer screen or in a magazine -- is called the resolution. The higher the resolution (ie, the greater the number of dots per inch), the sharper the picture will be.
Computer pictures are stored in 'files' on computer disks, and they take up lots of space. There are lots of different 'formats'. Those commonly used on the Web are GIF (Graphics Image Format), JPEG (Joint Photographic Experts Group) and PNG (Portable Network Graphic). For magazine work you might use TIFF (Tag Image Format File), EPS (Encapsulated Postscript), or dozens of others.
The GIF format is suitable for small images with sharply defined areas such as buttons with text, logos, etc., JPEG is useful for larger pictures, and particularly photographs. This is because the picture file is electronically scrunched down in size so that it can be transferred more quickly from the Internet to your web browser. The PNG format is newer, and not all browsers can handle it as yet.
Small is beautiful
In general, larger pictures take up more space on your hard disk. If you had a 1" square picture to store, you would need to store (72 x 72 = 5184) dots at screen resolution, (600 x 600 = 360,000) dots at typical laser printer resolution, and (2400 x 2400 = 5,760,000) dots at magazine resolution. Make that last one a 6" x 4" picture and you need room to store 138,240,000 dots. That's a heck of a lot of dots!
There are two reasons to keep your graphics files as small as you can. Not only do you have to find room for them on your hard disk, you may also need to move them around from time to time (try emailing the last example above with an ordinary modem and it'll take you a month of Sundays!) And if you are designing a web page, you need to keep your graphics as small as possible. Every picture on your website has to be transferred over the telephone line to your visitor's browser -- they'll get fed up and go elsewhere if your pages are too slow to load.
The ultimate aim is to have as sharp a picture as possible stored in the smallest file size. This is called a 'trade-off'. The question you need to ask is "Where will this picture be seen/displayed/printed?"
If your picture is going to be printed in magazine, you have no choice but to scan/process/store it at something like 2400-3600 dpi. However, if it's only going to be seen on somebody's computer screen, there is no point at storing it at anything more than 72 dpi, which will make your file size MUCH smaller.
Compressing images
When the Internet first started, there was suddenly a need to transfer pictures around using slow computers, so a group of people tried to come up with a way to make picture files smaller. What they came up with 'compresses' pictures. It uses mathematics to crunch the picture down when it is stored, and reverses the process to bring them back to full size when they are needed. This is what the JPEG format, amongst others, does.
The only problem is that each time a JPEG picture is saved to disk, it loses some of its detail. (This is only when it is worked on -- it doesn't do this when you just look at it). If you get to the stage where you're working on your own pictures with graphics software, keep your original images at high resolution in something like TIFF format, and only convert them to low resolution JPEGs when you need to.
Working with your pictures
You can't alter the size or shape of a conventional picture without a pair of scissors, and altering the colours takes specialist techniques.
Computer pictures, on the other hand, are fairly easy to mess around with. All you need is some graphics software (often included free on home PCs, or found on magazine cover disks). However, before you start fiddling with those digital pictures, you need to work out what you want to achieve.
Here are some basic rules to follow.
Rule 1 (and the one you never break) -- keep your original images stored safely away and copy them to work on. If you mess up the copy you simply go back to the original. Mess up your original and there may be no way to go back to how it was.
Rule 2 -- keep the resolution as low as you can get away with. If your picture will only be viewed on a computer screen, there is no point in it being higher than 72 dpi resolution.
Rule 3: decide which bits of the picture are useful, and crop (get rid of) the rest. If you have two people in the middle of a huge green field, you can probably cut some of the background. You can often choose whether to make your picture smaller or enlarge the people a bit!
Rule 4: Reduce the size of your picture if possible. A typical home computer screen is still only 800 pixels wide by 600 high, so there is no point in having a 1200 pixel wide picture -- it just means your visitors have to scroll around it. A decent sized web image should be 590 pixels wide, max -- and that's on the large size.
(By the way, if you are writing your own web pages, don't be fooled by your ability to say how big the picture should appear to be. If the picture stored on your disk is 1600 x 1000 pixels, that's what gets transferred over the Internet, no matter how small you tell the browser to display it!)
Rule 5: If your pictures are going to be printed at the other end, find out what 'resolution' the printer will be. Inkjet printers mostly do from 100-250 dpi. Laser printers are mostly 300-1600 dpi. Again, there's no point in sending higher resolution pictures than are needed.
Scanning
If you have a scanner, you can usually control most of the things we've already talked about, including the resolution, size, saving as JPEG format, etc. If you can, set your scanner options to: 72 dpi resolution; size only as large as you need, but no bigger than 400-600 pixels; 24 bit RGB colour (for JPEG photographs) or 256 paletted colour for GIF images; output format JPG.
