Gavin Crawford wrote:
In article <4485F791.9000609@xxxxxxxx>, Clive Bonsall <C.Bonsall@xxxxxxxx> wrote:
Thanks for this. Undoubtedly, I am using bigger images than I need to. But I'm unsure about the optimum mode/dpi setting to use, so advice
would be appreciated.
For non-colour stuff, I tend to scan everything at 8bpp grayscale and the highest resolution (dpi) that my computer can manage, because I can always reduce the images to 1bpp and/or lower resolutions, as/when required.
The JOB is this ... a book DTP'd using OPW, which will contain lots of line drawings and B&W photos.
First, I think it's important to distinguish between the two different types of images you will be using in your book.
Lets start with the easy ones - B+W photos. These are in fact grey-scale images and you will want these at 8bpp to give you the range of grey tones you'd expect in a photo.
What can often cause confusion is that one person may refer to black and white while describing a grey scale image (such as a photo), while somebody else will take it to mean a 1bpp image. A 1bpp image is referred to as 'line art' and is ONLY black and white with no other tonal (grey) levels. If there are other grey values in the image then it cannot be called line art, even if the picture is drawn as lines.
It will be sent to a commercial printer either as camera-ready copy or as a series of PDF files. For the line drawings what would be the optimum resolution -- e.g. is there anything to be gained by having the images at 1200dpi or even 2400dpi, or will 600dpi suffice?
There are some general guidelines that many people work to when producing artwork/origination for printed mater. In reality there are many factors that come into play when deciding on image resolutions, such as printing method (litho, screen, digital press, di press etc)...
[snip]
I'm just trying to think if I've covered everything. Probably not, so if you are not sure just ask. Having spent over 20 years in the prepress/print industry I find it difficult to sum up that experience into a few paragraphs when someone asks me 'how do you want it?'.
