S45: 4 meg pixels good enough for commerical printing

[ultra7]

HI,

If I use my S45 to take pictures at 4 meg pixels, fine setting JPEG format, will it be good enough to use for commercial printing(brochures)?

For commerical printing they usually need the pics to be in 300DPI. when I check the pictures I take in photoshop, it shows the 4 meg pixels files have a resolution of 180DPI.

There is no way the S45 cna save in TIFF format, and apparently the RAW format(is this TIFF) cant be open in Windows XP.

Anyone can advice.

[JamesG]

The resolution depends on the size you want to print at. With a print 6 inches wide the resolution at 4megapixel becomes 378dpi or so.

When using RAW mode, you need to open the files in the canon FileViewerUtility that came with your camera. This program can then turn the RAW file into a TIFF.

Another alternative is BreezeBrowser.

hope that helps,
James

[UK_Terry]

Shoot in RAW then use BreezeBrowser to Convert to TIFF

http://www.breezesys.com/

Irfanview will allow you to view RAW files as well

Http://www.irfanview.com

[Traste]

DPI and PPI are relative numbers and really do not apply as long as the image is inside the computer, they are just a factor when calculating the resolution in relation to a size of the picture on a physical media such as a print out (or indeed the screen)

[klee]

Traste, based on what you said then, what is the number of DPI or PPI that we should aim for in each respective print sizes category (6x4, 7x5 etc) especially when when I try to crop 3.2 or 4 Mp jpgs? The aim being to produce a cropped jpg file that has enough pixels to satisfy ensure a satisfactory print on film paper. I distinctly remember this ability to crop and still make excellent resolutioned prints to film paper was one of the prime benefits of 3.2 and 4 Mp cameras.

Or does it all not matter? and I'm talking bollocks :)

[Traste]

The point is.... a point is a point is a point. And as long as its inside the computer, a pixel is a pixel is a pixel.
The pixel have no size, you can't measure it in inches (ok we can theoretically measure the length of the sectors on the heard disk that pixel would take but I wont go there).
What DPI / PPI you should aim for depends on the equipment you intend to print it on.

If you have the resolution of an image and a DPI on a printer, you can in a sense calculate the size of the printed image.
But ... in the computer there are no inches...

[CyberDyneSystems]

Ultra7,

Yes 4 Megapixels is enough for commercial printing. The size of the printout obviously is a consideration,.. but in recent years 4 megapixels was the best anyone had to work with. Hundreds of thousands of commercial jobs have gone to print with 4 megapixels or less. It is plenty.

Keep in mind some of the best DSLRs are about 4 megapixles or less. D30,. 1D! not to mention D1H etc.

To get the best results from those 4 megapixels,. read the instructions about raw format posted above by UK_Terry etc.

But Jpeg will suffice for many applications.

[Jamie]

Ultra7,

I work in print/design. I'll just add my two cents.

DPI

On the matter of dpi. Photographs don't have a dpi when you take them, because dpi only relates to phisical size (ie number of dots per inch). It's only when you print photos out that they have a dpi, because they then have a physical size. But their dpi depends on how big you printed them.

For example, if you take a photo on your S45 and print it out so big that it fills a wall, and each pixel is one inch big, then the image is 1dpi. However, if you printed the image really small so that the whole image was only 1 inch wide, then the image would be 2272dpi. Because all 2272 pixels of the image would be crammed into that one inch.

File format

First of all, don't worry about saving in jpeg format. Just use the highest setting and it will be fine. As long as it's a high res photo (and it will be) then it doesn't matter at all that it's a jpeg. However if you wanted to use lossless images like TIFFS then take the photos as the "RAW" format. You can then convert them to any other file type on any computer whatsoever.

Resolution

If someone gives me a 4 megapixel photo to work with I'm delighted! It's pretty rare you get anything to work with that's higher resolution than that.

4 megapixels is fine for almost all kinds of commercial printing.

If it's printed full page A4 (magazine), it will still be 206 dpi. Which is more than enough. Anything over 150 is fine.

While many printers insist on all images being 300dpi, that's really just a guideline. (And it gets them out of trouble if your prints look crap due to low resolution.)

The only situations where you may need more than 4 megapixels is for large displays such as large wall panels, fridges etc. - in which case it would be ideal to have a higher resolution.

However, you usually find that the larger the object, the lower the dpi the printers use for the actual print. Plus people must always stand farther away in order to view it.

In other words you don't have to worry about dpi unless it's a very, very important large display that people are likely to go right up to and look at small areas of the photo in detail. This rarely happens.

The only example I can think of where high resolution would be important is say if you wanted a huge ariel photo of your city printed across a wall, so that people could go up to it and look at all the little houses. But other than that sort of thing, don't worry. People expect huge photos to look a little blurry/pixellated when they walk up to them.

Most large commercial photo displays aren't that high dpi. Even for the huge corporations.

The sad reality is that although everyone would like photos to be 300 dpi at all times, designers often take photos and scale them, which reduces their quality a lot. Then printers lie about the dpi of their prints. And on top of it all, the combined dpi of the image and ruling of the print make the actual effective dpi way lower than it should be.

So don't worry about it too much.

Hope this helps.