Photo enlargement for printing

[prh]

I would like to have some larger digital photos (eg 24"x18") printed at a lab where they require the images to be maximum quality jpegs scaled at 300ppi. The native resolution of my images is 10.1mpixel so I will need to upsize the images.

I plan to do raw conversion to tiff and convert to jpeg only at the last stage. I'm using Linux.

So, some questions (a site search didn't really reveal what I want):

How can I use ImageMagick to: take a 8 or 16 bit tiff, upsize it to required size, sharpen it, convert to jpeg. Batch processing would be nice.

Also, images need to be colour managed. I can handle that with raw conversion, and can embed printer profile. Will the icc be transferred during conversion?

Finally, can I expect reasonable results from the conversion? My camera is a dslr with good glass.

Any assistance will be appreciated.

Paul H

[Bonzo]

I would guess you want something like this:

Code: Select all

mogrify -profile filename -resize 7200x5400 -density 300 -sharpen -format jpg *.tif

This will resize all tif images in the folder changing the dpi and sharpening them saving as a jpg. I would recomend trying this on some copy images first as it should save to jpg but if you get it wrong mogrify will overwrite the originals. You may need to play with the code to get exactly what you want; I have never used the profile option.

Have a look at the information here http://www.imagemagick.org/script/comma ... hp#profile

[prh]

I think I get the idea, and I will probably use "convert" in order to preserve my base images.

Does ImageMagick process options in the order specified in the command line?

Thanks for your assistance, Bonzo.

Paul H

[Bonzo]

I beleve IM processes most commands in order and I read some where its better to use sharpen before resize.

I would just try some variations of the code and see what works best for you.

You may also want to change the filter used with your resize.

[prh]

Thanks. Time to experiment!

Paul H