Here is Michael Sullivans website that I've been yapping about scanning.
he gives some great info and tips
Also I just got my scanner and photoshop, I've been asked to scan some slides for use on a web site. So I thought sure I'll just scan these babies in and reduce the dpi to 72 under image size and send them. But when I change the dpi the image also gets soooo small. Too small if fact, I really was surprized this changed the size as well I thought it would just effect the resolution. Or am I completely mixed up??? Gosh I hope this doesn't make me sound ......Dumb
The image seen on screen gets smaller perhaps because you are still seeing it at the same *percentage* size. Of course an image with 72 pixels per inch is "smaller" than one with 300. Hit command+ to make the screen image larger, or command 0 (zero) (Photoshop 4 only)to fill the available space on your monitor. When the image is at 100% you see every pixel. You can reduce the Image size independently of the resolution, or vice versa depending on which options you check in the "Image size" dialogue box.
Does that help? I would recommend scanning at a high resolution then reducing the res in Photoshop (as you are doing) rather than scanning at 72ppi.
As for a scanner, we purchased a UMAX Astra 610 six months ago. This scanner is available for Macs and PCs, for less than $100, and it is equivalent in quality to scanners that cost $1500 about five years ago!
There's a place in Boulder that scans flat surfaces up to 36 x 48". It's called Photocraft, (303)442-6410. 3550 Arapahoe, Boulder, CO.
It is normal working procedure to work from anywhere between 125% to 200% larger. Keep two things in mind. If you intend your work to be directly scanned, the most common size of the cylinder is 20 by 24 inches, so you need to work under that. The other thing to consider is your client. Some clients have standards to work with. For instance, I understand that some greeting card companies ask for work at 200%. Ask your AD.
Jessica, if your work is going to be commercially printed, the industry standard has always been to use a scan resolution that is approximately double the line-screen of the printing (which has to do with the number of dots-per-inch in the printed halftones). While there may be a wide variation among commercial printers, you're usually safe scanning at 300 ppi (pixels per inch). Most printers use a line-screen of 150-175 dpi.
If you scan in artwork, then yes, it becomes "pixelated." However, sooner or later, pretty much all artwork gets scanned in for printing these days. The trick is to scan at high enough resolution that the pixels don't become objectionable. For color or halftone work this is typically about 300ppi (pixels per inch). For pure linework (eg, pen and ink drawings, etc.), it can be much higher ... like around 2400ppi.
It's really pretty easy. Just give yourself plenty of overlap. Once you have your pieces scanned, open one (for example, the upper left piece) in Photoshop. Enlarge your canvas size to accomodate the entire finished image, with your current piece in the upper left.
Once that's done, bring in the second piece on a new layer. I usually make this layer somewhat transparent temporarily until I get the image positioned where I want it.
Since scanners seldom scan exactly the same from edge to edge, you may have a little distortion on the edges of your scans. This is why I recommended the overlap. It might be helpful to place a guideline at the point where the splice looks the most accurate, then erase the overlap to (or almost to) the guideline.
Repeat with the remaining pieces.
Once you've finished lining them up, make all the layers opaque and check all the seams. If they line up to your satisfaction, flatten the layers and save your new image.
Date: Tue, 16 Feb 1999 16:29:56 +0000
From: Heidi Schmidt
Subject: Re: illustration: Mad client
I'm new to this group so I thought I would introduce myself by helping you with your question. I am an illustrator as well as a print designer. It sounds like you used your scanner software to save your images. This is not always a reliable way to save images. The best way to clean and check resolution is to take the images into Photoshop after you have scanned them. Check to see if your scanner software has a Photoshop plugin. If it does then your scanner software will open in Photoshop. If you don't have Photoshop you can download it for a free trial on the Adobe website. If the images looked funky after your client printed them at Kinkos then they (Kinkos) probably opened them in Photoshop to check the resolution. Here's some stuff I have learned:
Scan line art at 600dpi, just to be safe
Check dpi after saving from the scan program
If the image is color for print make sure it is saved in CMYK not RGB
300dpi for color images printing at 150 line screen
Never increase an image size more than 130% unless you have scanned at a resolution higher than 300dpi
Save line art as bitmapped tiffs
Jpegs are good eps is better
This is probably more info than you need. If you are still confused get the latest Photoshop WOW book from Peachpit Press. Even if you don't have Photoshop it will help you understand how to scan stuff for print. Just be thankful that it didn't go to print, although Modern Postcard would have caught it before printing. I would offer to knock off some money from the clients bill and consider it a learning experience.
p.s - Check out my site to see my illustration!
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