PPI and resizing for printing Christmas gifts help, please

[Robin with the crazy GSD]

I am a beginner at Photoshop and I have read the article on adjusting resolution of images, but I definitely need some help. I hired an small company to create 4 digitals of portrait artwork at 300 PPI to print at 16" x 20" for Christmas gifts. I've only received 3 of the 4 portraits so far (after a month and a tons of emails).

The image size dialog boxes say:

portrait #1: 62.5" x 50"  with 96 PPI

portrait #2: 27.778" x 22.222" with 72 PPI

portrait #3: 66.667" x 83.333" with 72 PPI

~Portraits #1 and #3 came up automatically to 300 PPI when I adjusted the image size to 16" x 20" with resampling unchecked. So I guess those are okay?

~Portrait #2 only came up to 100 PPI with that same method. So I guess I need to check the Resampling box. And then what? Since it's a portrait, would I choose Bicubic Smoother or Preserve Details? Or should I revert to the original size of 27.778" x 22.222" and THEN check the Resampling box and proceed? Can someone please help me, step-by-step to get this portrait to 300PPI and 16"x20"?

Thanks in advance! Hopefully, Portrait #4 (if it's ever completed) will work with one method or the other...

[D Fosse]

First of all, you must understand what pixels per inch, ppi, means. It's a lot simpler than people think: it means exactly what it says, no more, no less. Pixels-per-inch. Read that absolutely literally, word for word, those three words. How many pixels per inch of paper.

An image doesn't "have" a ppi number. The image is just pixels. The ppi number is assigned later, defining the pixel density on paper and thereby the print size.

You can use the ppi number as a guide to resampling. Then it's just simple math. Upsampling 100 ppi to 300 ppi means 3x the linear dimensions - or 9x the area; 9x as many pixels. Where do these pixels come from? That's right, nowhere. They have to be invented out of thin air.

You cannot just upsample a pixel image to 9x the area and expect it to look good. It will look awful. You need to get a better image!

Also see the last post in this thread from today (just so I don't have to type it again):

https://community.adobe.com/t5/photoshop-ecosystem-discussions/best-way-to-enlarge-the-image-without... 

[Robin with the crazy GSD]

First of all, thank you for finally helping the light come on for me regarding PPI! And I did take your advice and tell them to start over with what something that is the quality they agreed to in the first place. (Fingers crossed. There is a huge language barrier, so communication has been rough. Wish I had realized that before I ordered. It has been a nightmare.) It finally clicked about the PPI and I was able to answer the question I was going to ask you...how will I be able to tell if they actually start over and redo the art or if they just resample it? I realized that I could right-click the artwork they send and check the pixel details under properties.  Thank you so much for taking the time to help me. And fingers crossed, for real. These are for my grandkids and only 2 of the 4 are getting a gift as it stands now. UGH)

[Robin with the crazy GSD]

Uh...the light was not really on, apparently. Because if they Resample it, it will show the correct # of pixels anyway (pulled out of the ether by the software). So is there a way to tell if it's been redone, other than it should look better on my laptop screen? I'm afraid it's going to be too small to be able to tell that it looks bad...my head hurts.

[Robin with the crazy GSD]

I just posted this question and for some reason, someone or some filter decided it was spam and deleted it. I am afraid to link my original post, in case that's what caused it to be deleted.

How can I tell if an image has been upsampled? I paid for 300 PPI when printed 16"x20" and received 100 PPI at that scale. I don't trust the company I bought it from. I think that instead of starting over from scratch, they might just upsample the 100 PPI image they sent. That's not the quality I paid for. I am also afraid that I won't be able to tell it's been upsampled just by looking at it on my laptop or comparing to the 100 PPI one they sent.

Can anyone tell me if there is an objective way to determine if the new image is really "new"?

Thanks in advance. Glad to have found this community of experts willing to share their knowledge. I hope this does not get taken down again...

[Kevin Stohlmeyer]

Hi @Robin with the crazy GSD I'll merge this with your original post since this is directly related to that conversation.

As for upsampling - there is no systematic way to confirm an upsample in PS, but you should be able to tell when you zoom in at 100%  the quality would be less if improperly upsampled.

Here is an image at 100% 100 ppi:

Here is the same image at 100% upsampled to 300 ppi:

Heres the image not upsampled at 300 ppi (purchased a larger version)

Note the quality in the details and color it's fairly obvious when upsampled.

[Robin with the crazy GSD]

Hi and thank you! That looks pretty unmistakeable. And thanks for merging.

[Robin with the crazy GSD]

Thanks so much to all who helped me with this issue. To my surprise, the company actually came through with a beautiful, redone artwork. I was able to check details, as you showed me, and it's truly a new artwork and NOT the unacceptable one upsampled! Just thought I'd let you know how grateful I am for all the assistance!

[Conrad_C]

~Portraits #1 and #3 came up automatically to 300 PPI when I adjusted the image size to 16" x 20" with resampling unchecked. So I guess those are okay?

By @Robin with the crazy GSD

Yes, that was the right way to do that. They already had the correct number of pixels, they just needed to be distributed across the correct number of inches, and when that was done, it worked out to 300 ppi.

~Portrait #2 only came up to 100 PPI with that same method. So I guess I need to check the Resampling box. And then what?

By @Robin with the crazy GSD

I tried it out and I would recommend this:

1. With Resample off, set it to 16 x 20 inches, which like you said will change Resolution to 100 ppi.

2. Enable Resample.

3. Change Resolution to 300 ppi, and that’s it. Because you don’t want to change the 16 x 20 inches dimensions.

The real solution, of course, is to have the company go back and provide you with a file that really is 16 x 20 inches at 300 ppi without resampling. Because the problem with resampling up from 100 ppi to 300 ppi is that the software is “making up” details to reach 300% enlargement, and that won’t look quite as good as if the original had 300 ppi of real details.

Now, the reason for the odd sizes is probably the way they saved the files. That’s because the way a printed size and resolution is preserved is if the file preserves the PPI metadata. The problem is, some save/export commands in Photoshop include the PPI metadata, and some leave it out to reduce the file size. You may have to tell them this part…to preserve PPI metadata, choose File > Save a Copy, and then choose the format (PSD, TIFF, JPEG…).

If instead they use a command on the File > Export submenu, such as Export As or Save for Web (Legacy), those commands do not preserve ppi metadata and so when opened in another application, the image will probably come up showing some kind of default ppi value like 96 or 72, which screws up the assumed print dimensions. This is probably what you are seeing. So if they are doing the work in Photoshop and they swear that Image Size looks right on their side, encourage them to use File > Save a Copy to preserve the ppi metadata.

[Robin with the crazy GSD]

Wow, I had no idea using Export As was the reason things I've created have come up as weird sizes! Thanks for that. And thanks also so much for working those Resampling steps out for me. I hope I don't have to use that, because I took both your and D Fosse's advice and told them to start over on that artwork. We'll see how that goes. As I mentioned in the reply to D Fosse, there is a huge language barrier. Wish I had known that before I ordered. And also as I mentioned in that reply, fingers crossed. These are gifts for grandkids and only 2 of the 4 have a gift right now...

[Robin with the crazy GSD]

Hi, everyone. I posted here yesterday (the link to my original post is below) and have since taken the advice of the two people who replied - I contacted the company I'd ordered artwork from and asked them to redo it from scratch. I'd paid for 300 PPI when printed at 16"x20". The artwork they sent me is only 100 PPI when printed 16"x20". Now I don't trust them to really start from scratch. I'm afraid they're going to upsample it and that is not the quality I paid for. I'm also afraid I won't be able to tell just by looking at the new image that it's just been upsampled. So my question: Is there a objective way to tell if a new image they send has actually been redone from scratch at 300PPI (at 16"x20") or whether they are trying to pass off the original upsampled to 300 PPI? I do have that original image to compare the new one to. If there's a problem, I hope to have something less subjective to tell them other than "The new one looks bad."

Thanks in advance. Very happy to have found this community of experts willing to share their knowledge.

 https://community.adobe.com/t5/photoshop-ecosystem-discussions/ppi-and-resizing-for-printing-christm...