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72 PPI HELP?!

kitkatdubs

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I am running into an issue with PPI - I import my RAW files into PS and it says "300 PPI" at the bottom. I edit my photos and then export them and it still says "300 PPI". However, today I decided to fix something on a photo and so I pulled it back into photoshop, the jpeg file and I noticed that it says 72 PPI not 300. WHY is it getting changed? I am so confused?!?!?! HELP! I edited 3 sessions and am just noticing this now?!!!!!!
 
The property of image in your computer is a resolution (like 6000x4000 pixels).
The PPI (pixels per inch) is not relevant until you actually print the picture - it is the resolution divided by physical size of the picture. And it tells you the picture's puxel density.

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The property of image in your computer is a resolution (like 6000x4000 pixels).
The PPI (pixels per inch) is not relevant until you actually print the picture - it is the resolution divided by physical size of the picture. And it tells you the picture's puxel density.

Odesláno z mého UMI_MAX pomocí Tapatalk


Ok, so this obviously matters if my clients will be printing the photos. They need to be at 300PPI and no matter what I do, I can't export the photo at 300 PPI... its like PS is changing it!?
 
Do you use a Canon camera?

You can set the print resolution (PPI) in Photoshop:
Image > Image Size - before export.
However, you may want to note that a print lab will change the print resolution as needed according to the size print ordered, regardless what you have set the print resolution to.

Because as fundy pointed out, print size is a function of the image resolution ( xxx px by xxx px) and the print resolution (pixels per inch - ppi).
Also mote that the ppi (print resolution)is meaningless for electronic display, because the resolution (and aspect ratio) of electronic displays can easily be changed.

It's likely your clients are even less informed regarding the ins and outs of having prints made.
Which is why it gets scary when one thinks about clients making prints on their own, or having print made when it comes down to image resolution, print resolution, print and image aspect ratios, and color management.

By the way - 300 ppi is a rule of thumb- not an absolute.
At some point as print size increases the print resolution has to be reduced to make the print because there is insufficient image resolution to make the print at 300 ppi.

300 ppi works OK for smaller print sizes but note for large prints. Which is why the best print labs minimum print resolution requirement is as low as 100 ppi.
 
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I am running into an issue with PPI - I import my RAW files into PS and it says "300 PPI" at the bottom. I edit my photos and then export them and it still says "300 PPI". However, today I decided to fix something on a photo and so I pulled it back into photoshop, the jpeg file and I noticed that it says 72 PPI not 300. WHY is it getting changed? I am so confused?!?!?! HELP! I edited 3 sessions and am just noticing this now?!!!!!!

You'll be a much happier person if you just ignore PPI. It's a meaningless piece of metadata that doesn't change anything "real" about the image. It's just a tag. You may as well set the PPI to "airplane" and it would be every bit as meaningful as any numeric value you assign.

Your image has some REAL number of pixels in it. The "PPI" label in the non-visible part of the file (meta-data) is JUST a label. Some software which chooses to not ignore it (because you can totally ignore it) might use that value to say "Oh hey... this person wants the image to display on a monitor such that every 72 pixels in this file should be spread out nicely across each one inch of the display". This begs another question which is... does that software actually KNOW how many pixels reside within every inch of the display? Usually not. In order for the value to be meaningful, typically YOU have to know the geometry of the specific digital device that will be used for display and then YOU can set the value in the file so that you know how much of the display real estate will be occupied by the image.

Many years ago, the 72 PPI value was used because the dot-pitch common to so many monitors allowed about 72 pixels per inch of screen. But that's not really true anymore. I have a 27" 5k display... it has a PPI of 220. So if you were assume that 72dpi made up one inch on my display then I'd get an image about 1/3 as wide and high as what was intended.

Think of the PPI as a "request" that doesn't actually have to be honored. It has nothing to do with your image quality or your file. If you want to change the quality of the file then you'd bring the software into something like Photoshop and ask it to "resample" the file.
 
Can I go back and change the photos from 72 PPI to 300 PPI??
 
I am running into an issue with PPI - I import my RAW files into PS and it says "300 PPI" at the bottom. I edit my photos and then export them and it still says "300 PPI". However, today I decided to fix something on a photo and so I pulled it back into photoshop, the jpeg file and I noticed that it says 72 PPI not 300. WHY is it getting changed? I am so confused?!?!?! HELP! I edited 3 sessions and am just noticing this now?!!!!!!

You'll be a much happier person if you just ignore PPI. It's a meaningless piece of metadata that doesn't change anything "real" about the image. It's just a tag. You may as well set the PPI to "airplane" and it would be every bit as meaningful as any numeric value you assign.

Your image has some REAL number of pixels in it. The "PPI" label in the non-visible part of the file (meta-data) is JUST a label. Some software which chooses to not ignore it (because you can totally ignore it) might use that value to say "Oh hey... this person wants the image to display on a monitor such that every 72 pixels in this file should be spread out nicely across each one inch of the display". This begs another question which is... does that software actually KNOW how many pixels reside within every inch of the display? Usually not. In order for the value to be meaningful, typically YOU have to know the geometry of the specific digital device that will be used for display and then YOU can set the value in the file so that you know how much of the display real estate will be occupied by the image.

Many years ago, the 72 PPI value was used because the dot-pitch common to so many monitors allowed about 72 pixels per inch of screen. But that's not really true anymore. I have a 27" 5k display... it has a PPI of 220. So if you were assume that 72dpi made up one inch on my display then I'd get an image about 1/3 as wide and high as what was intended.

Think of the PPI as a "request" that doesn't actually have to be honored. It has nothing to do with your image quality or your file. If you want to change the quality of the file then you'd bring the software into something like Photoshop and ask it to "resample" the file.


Very interesting Tim! SO my export settings say that the screen resolution is 72, but print is 300. Does that mean it will be 300 PPI then? I'm so confused b/c when I pull the photo back into photoshop after exporting, it says 72. But does that mean really is 300 for print? Check out my screen shot? So should I be "Saving As" instead so it doesn't change the PPI?
 

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The property of image in your computer is a resolution (like 6000x4000 pixels).
The PPI (pixels per inch) is not relevant until you actually print the picture - it is the resolution divided by physical size of the picture. And it tells you the picture's puxel density.

Odesláno z mého UMI_MAX pomocí Tapatalk


Ok, so this obviously matters if my clients will be printing the photos.

No in fact it doesn't matter.

ppi.webp


That's the same image at two different PPI values. The PPI value has no effect on the actual image pixel dimensions. It is simply recalculated when you change the print size.

They need to be at 300PPI and no matter what I do, I can't export the photo at 300 PPI... its like PS is changing it!?

The PPI will change at time of printing when the print size is specified. PPI is pixels per inch. Change the number of inches in the print and the number of pixels per inch has to change if you have a fixed number of pixels.

Joe
 
The property of image in your computer is a resolution (like 6000x4000 pixels).
The PPI (pixels per inch) is not relevant until you actually print the picture - it is the resolution divided by physical size of the picture. And it tells you the picture's puxel density.

Odesláno z mého UMI_MAX pomocí Tapatalk


Ok, so this obviously matters if my clients will be printing the photos.

No in fact it doesn't matter.

View attachment 130261

That's the same image at two different PPI values. The PPI value has no effect on the actual image pixel dimensions. It is simply recalculated when you change the print size.

They need to be at 300PPI and no matter what I do, I can't export the photo at 300 PPI... its like PS is changing it!?

The PPI will change at time of printing when the print size is specified. PPI is pixels per inch. Change the number of inches in the print and the number of pixels per inch has to change if you have a fixed number of pixels.

Joe

Ok got it! Thank you- what I am now trying to understand is it says when i export it screen is 72 PPI, however print size is 300 PPI ... does that mean its still 300 PPI? Even though when I pull it back into photoshop its 72 PPI. HAHAH AHHHHH Can someone call me on the phone and talk to me about this, seriously! I need some help!
 

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  • Screen Shot 2016-11-13 at 8.45.34 AM.webp
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Most of my customers are printing thru tiny prints or shutterfly for holiday cards and their PPI recommendation is 300, which I haven't given them b/c I just realized now it says 72 or is it really 300 PPI b/c it says print resolution is 300PPI for my screen, right? Am I reading that right?
 
Ok got it! Thank you- what I am now trying to understand is it says when i export it screen is 72 PPI, however print size is 300 PPI ... does that mean its still 300 PPI?

It was never 300 PPI to begin with. It is no PPI until it is coming out of the printer. If there is no physical printer in front of you and that printer isn't spraying ink on paper that is moving through the printer then there is NO PPI.

PPI becomes real when print size is specified and not until then.

Joe

Even though when I pull it back into photoshop its 72 PPI. HAHAH AHHHHH Can someone call me on the phone and talk to me about this, seriously! I need some help!

You're worrying about something that isn't real.

PPI doesn't change anything it tells you something.
 
Most of my customers are printing thru tiny prints or shutterfly for holiday cards and their PPI recommendation is 300, which I haven't given them b/c I just realized now it says 72 or is it really 300 PPI b/c it says print resolution is 300PPI for my screen, right? Am I reading that right?

When your customer picks a print size in the software at their computer the PPI will change right then and there. If you set it to 10,000 PPI it wouldn't matter one iota. As soon as they select a print size the PPI will change.

The print company will decide to leave it alone or modify it and they'll not tell you.

Joe
 
Ok got it! Thank you- what I am now trying to understand is it says when i export it screen is 72 PPI, however print size is 300 PPI ... does that mean its still 300 PPI?

It was never 300 PPI to begin with. It is no PPI until it is coming out of the printer. If there is no physical printer in front of you and that printer isn't spraying ink on paper that is moving through the printer then there is NO PPI.

PPI becomes real when print size is specified and not until then.

Joe

Even though when I pull it back into photoshop its 72 PPI. HAHAH AHHHHH Can someone call me on the phone and talk to me about this, seriously! I need some help!

You're worrying about something that isn't real.


But it matters to the clients b/c they will be printing these...
 
So last year, I had a client print thru Tiny Prints and they came back to me saying the photo was very blurry. Tiny Prints called me and explained that it was at 72 PPI and needed me to change it to 300 PPI. I do not want that to happen again this year..
 
So last year, I had a client print thru Tiny Prints and they came back to me saying the photo was very blurry. Tiny Prints called me and explained that it was at 72 PPI and needed me to change it to 300 PPI. I do not want that to happen again this year..

Look at my first post and the graphic. I circled in red a box titled resample -- that's Photoshop (CS6). That could be the issue. That should be checked off by default. When that is checked off changing PPI is meaningless. But it is possible to have an accident and check that on and not realize it. Then you could make a change that would lower the resolution of the original photo.

Joe
 

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