Resizing

fredjclaus · October 15, 2009

This really isn't a "techie" question but I'm lost. I have just started using PhotoShop CS3, and I need help resizing. A company wants me to submit samples of my photographs in 72 ppi size images. How do I do that in PS?

jfriend · October 15, 2009

In order to resize an image you need to know either:

How many pixels you want in the final image (height and width). For example, they could ask for an image that was at least 5000 pixels on the long side. Or, they could ask for an 18 megapixel image.

or
Both the dpi and the size of the image (height and width in inches or centimeters). For example, they could ask for 72 dpi at 20" x 30" which would be 72x20 = 1440 pixels on the short side and 72 x 30 = 2160 pixels on the long side.

You cannot resize an image knowing only the dpi.

It is also possible that they don't have a clue what they are asking for and all they really want is for you to set the metadata on the image to be 72dpi without any resampling (doesn't change the actual pixels at all). That is generally a dumb thing to ask for (since it doesn't change the pixels at all), but if that's what they insist on, the metadata can be changed in Photoshop to say that. It must be done the right way in order to not throw most of your pixels away.

Art Scott · October 15, 2009

jfriend wrote:

In order to resize an image you need to know either:
How many pixels you want in the final image (height and width). For example, they could ask for an image that was at least 5000 pixels on the long side. Or, they could ask for an 18 megapixel image.

or

Both the dpi and the size of the image (height and width in inches or centimeters). For example, they could ask for 72 dpi at 20" x 30" which would be 72x20 = 1440 pixels on the short side and 72 x 30 = 2160 pixels on the long side.

You cannot resize an image knowing only the dpi.

It is also possible that they don't have a clue what they are asking for and all they really want is for you to set the metadata on the image to be 72dpi with any resampling (doesn't change the actual pixels at all). That is generally a dumb thing to ask for (since it doesn't change the pixels at all), but if that's what they insist on, the metadata can be changed in Photoshop to say that. It must be done the right way in order to not throw most of your pixels away.

images sooc are normally at 72 dpi.....now if you are sending images that have been resized at some point go back into PS go to Images > IMage size> pop up box will give the dimension in pixels or inches and dpi.....change the dpi to 72 all other numbers will change accordingly....make sure that the resample box IS NOT ticked......make sure the CONSTRAIN PROPORTIONS box is ticked.......clik ok and eureka you now have a resized image but none of the pixels have been lost and none have been interpolated to cause nasty jaggies (noisy pixels)..........your image is still the same pixel size.....pixels x pixels .... only the inches x inches will have changed .......

AND if actual up or down rezing is needed to satisfy their needs then go to OnONE software and download a trial copy of GENUINE FRACTALS and in one step do the rezing with out loss of resolution......you get approx 20 file rezes that can be saved on the trial version.....always preview the work before saving......as long as you do not save it does not lower your count....play with it a bit before you save your work so you can see what it does.......and as far as I can tell GF does not strip meta data like "saving for the web" in PS does......I have never down rezed but have uprezed a few hundred files........

Good Luck................

Sam · October 16, 2009

Number one.......................dpi has no meaning when referring to a digital image. :bash

Second the request for samples at 72 ppi tells me they only want small file sizes to view on a computer. If I had any questions I wouldn't hesitate to contact them.

You might ask if 800 pixels on the long side will be sufficient. The answer will give you the information you need.

One tip: When down sizing add some sharpening to the image, and convert to sRGB color space.

Sam

wayne861 · October 16, 2009

Art Scott wrote:

images sooc are normally at 72 dpi.....now if you are sending images that have been resized at some point go back into PS go to Images > IMage size> pop up box will give the dimension in pixels or inches and dpi.....change the dpi to 72 all other numbers will change accordingly....make sure that the resample box IS NOT ticked......make sure the CONSTRAIN PROPORTIONS box is ticked.......clik ok and eureka you now have a resized image but none of the pixels have been lost and none have been interpolated to cause nasty jaggies (noisy pixels)..........your image is still the same pixel size.....pixels x pixels .... only the inches x inches will have changed .......

AND if actual up or down rezing is needed to satisfy their needs then go to OnONE software and download a trial copy of GENUINE FRACTALS and in one step do the rezing with out loss of resolution......you get approx 20 file rezes that can be saved on the trial version.....always preview the work before saving......as long as you do not save it does not lower your count....play with it a bit before you save your work so you can see what it does.......and as far as I can tell GF does not strip meta data like "saving for the web" in PS does......I have never down rezed but have uprezed a few hundred files........

Good Luck................

The trial version of Genuine Fractals won't help - it splashes a watermark all over the image.

Wayne

fredjclaus · October 18, 2009

Thanks for the help everyone. I did downsize the images to about 1000 on the longest side. The gentleman that I spoke with doesn't know why the just told me dpi, but he gave me the correct information.

Thanks again for the assistance.

Resizing

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