Question concerning saving-sizing images...

[Fred Ball]

After clicking (save picture as) and then importing into
Corel 12, how do you resize without losing clarity and so on.
Tried changing to bitmaps, black & white-line art, stucki, etc. but still image not clear enough to give a good image for lasering.
Can anyone help, please!!!

[Mark Dickens]

Fred,

The first thing you have to look at is the resolution of the image. If you are getting the images off of the web, they will be 72 DPI (dots per inch) and are not suitable for engraving. The minimum acceptable resolution (my opinion) is 200 DPI. Increasing resolution (while maintaining size) or size (while maintaining resolution) of any photo will cause pixelation (blurring). There are some packages out there that are better at scaling up than the standard bilinear transformation used by PhotoPaint, PhotoShop and others. One of these packages is Genuine Fractals and they have a demo copy you can download. Having said this, the fact remains that if you are scaling up or increasing resolution without commensurate downward adjustment of the other factor, you will get a blurry image. The best images for engraving are sharp, large and high resolution. The tools you mentioned are used for conversion to a binary bitmap. In some cases, you can use the unsharp mask tool to slightly oversharpen the image and then convert to black and white using one of the error diffusion tools, such as Stucki (my favorite).

I hope that some or all of this helped!

Mark

[Nick Adams]

There are a few problems when resizing most images.

The majority are when you resize images that start at to low of a resolution.

A tip I learned through a photoshop gurus is that if your file size remains the same ...no matter how large or small the photo gets... it will still have the same content. If however the file size changes and gets larger you have added in information (pixels) where there origianally weren't any. The same hold true for shrinking. If the file size gets smaller then some of the content, or pixels, were removed.

Now that I got that out of the way. A file from a 6.2MP camera is about 21 inches x something @ 72dpi. When you downsize this through the use of !!!RESAMPLE!!! You will naturally be increasing the resolution to compensate for the downsizing of the photo. In both Corel and Photoshop and I assume Jascs Paint Shop Pro, you would pick a desired dpi and scale the size of the photo to match the file size of the origianal.

Naturally there are times when this wont work. But very seldom when you cant scale an image to say 600 or 1200 dpi then crop the image to the size you need it to be. I personally find Adobes' Photoshop to be the best at this function. I believe the Adobe Elements version that you can nab for 100 or so will do the same function.

Other people on the forum will have different software packages that they use also, and may very well know some that do this easier that others.

Hope this helps!

Nick Adams
Central Indiana

[Aaron Koehl]

Remember, too, that Corel often aliases (read: blurs) images in its preview window, even when zoomed at "100%". This aliasing isn't carried over when sent over to the printer driver (unless you resize, but that's a different issue).

[Fred Ball]

Many thanks again for all the excellent info. I will try and see if I can get this to work out.