Digital Photos and Photo Enlargement - How To Get The Best
Results
As I travel around the Web reading various information on the
correct methods for enlarging digital photos, I am amazed at the
variety of advise that is out there. Although the best methods
for digital photo enlargement can greatly depend on the types of
software used in processing the original photo and the printer,
and printer software, there are a few basics that should be
followed no matter what system is used.
The main issue with maintaining original image quality when
enlarging digital photos is to resample or interpolate the
original image only when absolutely necessary. I know that
common knowledge says that you need an input file resolution of
300dpi for quality prints, but this is just not necessarily so.
When you resample a digital photo to artificially boost file
resolution, the image pixels are rebuilt, averaging the image
data between pixels to produce the new image file. The resulting
image file is degraded in the process. The greater the
parameters of the resampling, the greater the degrading of the
image.
If you are using an image editor program like Photoshop to size
your digital photo, first resize the photo to the target print
size with the "resample" box unchecked. Using the original image
resolution from the camera, this may or may not drop the image
dpi below what you may consider sufficient for a good quality
print. Depending on your print setup and system, I would try an
input ppi of as small as 100. Print one and see what you think.
The printer will reprocess the file to the resolution of the
printer in most cases.
The second basic for quality digital photo enlargements is do
not sharpen the image file until after the file has been
enlarged to the target print size. Sharpening the file has the
same effect on the pixels as resampling, and will cause the
image to get an "edgy" or very slightly pixelated look if done
before the photo is at the target size. Always use the "unsharp
mask" method of sharpening and experiment a bit with settings
while watching the actual effect on the photo elements.
Oversharpening will also create an "edgy" image.
Photo enlargement of digital photos can be a somewhat
complicated thing if you are using very advanced softwares and
image processing programs. Of couse utilizing these programs
will yield results that are unmatched by the average digital
imager. You can get very good digital photo enlargements using
your image editing software and desktop or medium format
printer. Just be careful not to "overproduce" the input file.
For complete detailed information on photo enlargement:
Photo
Enlargement
Digital Photo
Enlargement
If you have any questions concerning this article, please feel
free to respond to: PhotoArt Imaging