Luminous Landscape Forum

Raw & Post Processing, Printing => Digital Image Processing => Topic started by: mbalensiefer on May 19, 2010, 12:38:52 am

Title: DPI in PS
Post by: mbalensiefer on May 19, 2010, 12:38:52 am

Hello.

 Is there an easy way to adjust the PPI of a digital image to a more Web-based 72 than the default settings I find in most of my .jpgs?

 If I resize a 300-PPI image to 72 (so that, for example, my imprinted fonts will show up easily without my having to grab the resize handle), then I lose the height/width resolution of the image.
 I would like to keep the height/width number of my pixels, while simply reducing the print PPI setting. Is this possible?

Thank you!

Title: DPI in PS
Post by: Slobodan Blagojevic on May 19, 2010, 01:46:15 am

You might want to check this thread (http://luminous-landscape.com/forum/index.php?showtopic=40946&st=0&p=341808&#entry341808) first.

Title: DPI in PS
Post by: mbalensiefer on May 19, 2010, 02:09:46 am

Hi Thank you, Slobodan, for your input.

 Still, I would like to keep the height/width number of my pixels, while reducing the print PPI setting. How this most easily done?

Thanks!!

Title: DPI in PS
Post by: Farmer on May 19, 2010, 06:46:53 am

You can't reduce the DPI and keep the same number of pixels in the width and height.  DPI is a function of pixels and how many of them are placed in a certain physical space.

Title: DPI in PS
Post by: mbalensiefer on May 19, 2010, 07:57:11 am

PPI. not DPI > Sorry.

Title: DPI in PS
Post by: AFairley on May 19, 2010, 11:46:01 am

In the image size dialog, uncheck "resample image" you can then enter any resolution value you want without changing the pixel dimensions of the image.

Title: DPI in PS
Post by: mbalensiefer on May 19, 2010, 12:06:24 pm

Thanks!
 Silly question:
 If I batch all my images to mark as 72 PPI, is this a destructive procedure (or does it just alter metadata)?

Title: DPI in PS
Post by: BobFisher on May 19, 2010, 01:22:08 pm

It's non-destructive from the standpoint that you've not changed any pixel information in the image itself.  

If you do it with TIFFs it's completely non-destructive.  

If you do it with JPEGs then keep in mind that any time you resave a JPEG you lose quality on recompression.  How much will depend on how much compression and how many times the image has been resaved previously.

Title: DPI in PS
Post by: Slobodan Blagojevic on May 19, 2010, 01:57:02 pm

Quote from: mbalensiefer

...  Still, I would like to keep the height/width number of my pixels, while reducing the print PPI setting...

Just out of curiosity, why exactly do you need to go through the extra step of doing it, given that PPI value is rather irrelevant for most practical purposes?

Title: DPI in PS
Post by: fdisilvestro on May 19, 2010, 02:59:06 pm

Importing images in some programs like Macromedia Flash 8 use image size (instead of pixels) and assume 72 dpi. That is the only case where I found it to be an issue. Maybe there was a setting somewhere in the software to solve this, but I could not find it.

Title: DPI in PS
Post by: mbalensiefer on May 19, 2010, 09:40:56 pm

Quote from: Slobodan Blagojevic

Just out of curiosity, why exactly do you need to go through the extra step of doing it, given that PPI value is rather irrelevant for most practical purposes?

 To standardize my text size, since PPI settings frequently mess up my work with text layers. )
Plus, I'd like my images to be similar across the board.