photoshop change my resolution when exporting

[lizettek95]

Holla!

Since updating to the latest CC, Photoshop has been struggling both with the drag and drop and now exporting . Every time I am trying to export files both in jpeg and png format. I save it in 300dpi but when I open the file in ps again it has dropt down to 72dpi. Every single time with different files. 

I did not have this issue until the update. Anyone else having this problem?

[D Fosse · Accepted solution]

This is nothing new, you've just noticed it now.

Export (and Save For Web) strips resolution metadata altogether. An exported file doesn't have a ppi value at all, neither 72 nor 300. It is ppi-less because it's not needed for screen use, only for print.

The ppi number you see when you reopen the file is just whatever default value the opening application assigns. In some apps it's 72, in some 96.

[lizettek95]

So I just have to accept that I never again can print my work or am I just dumb now that don't understand this because as said I didn't experience this in the erlier version..

[rob day]

Also, if you are placing and printing from a pagelayout the effective output resolution is relative to the image’s scale. If you check the image’s dimensions in Image Size you‘ll see the resolution went from 300ppi to 72ppi, but the print output Width and Height dimensions also increased by 416% (the pixel dimensions are unchanged).

If you place the image on an InDesign page, and scale it down to the original dimensions (24%), its Effective output resolution will be scaled back to 300ppi.

But why save as JPEG? Why not save as PSDs?

[Chuck Uebele]

Use save as rather than export or save for web, if you want to print your images. Export and save for web, are just for web images.

[lizettek95]

That does not solve the problem i'm afraid

[D Fosse · Accepted solution]

If you intend to print, you use Save As (which BTW does retain the ppi value).

If the image is for screen/web/mobile, use Export.

[zeno jones]

Sir! thank you much. I looked online for hours about this and your simple solution was the answer. I've never known my entire photoshop life (like 10 years) that export and save as will give diffrent results. The image size went from 2.3MB in export ass (best settings) to 7.2MB in save as.

Thank you my postcard printing is at a new level now!

[D Fosse]

Let's just wrap this up while we're at it, because there's a basic misunderstanding here that is admittedly very easy to make:

In most other software, the normal method for producing a finished file is "export". That's what you look for when the work is done. Not so in Photoshop. Here you use "Save As" to produce a new, finished "master" file. Save As is what you normally do. By master file I mean a full, complete new file, one fit for storing/archive, further processing later, sending out to others - and printing.

In Photoshop, Export is a very specialized function for a specialized purpose - namely, to optimize a file for web and mobile devices. A big part of that is reducing file size in every possible way, including stripping out everything not strictly necessary. That's why the "pixels per inch" metadata are removed. It's not needed for the intended purpose, screen and web.

That was pretty clear back when Save For Web was the promoted tool for this. Now that's on the way out, they very unfortunately named its successor Export, which only leads to all kinds of confusion like here.

As for why ppi is irrelevant for web, it's because a screen already has a resolution: the screen pixel grid. On paper, there is no such grid, so one has to be invented, and that's the "pixels per inch" number. It defines the pixel density on paper, and thus how big the image will print. Size and ppi are inverse: as one goes up, the other goes down.

[staceymorris]

The problem is POD sites like Amazon, Red Bubble, etc, want 300 ppi and PNG files uploaded. They will not accept photoshop files. If we are designing for these sites we need to be able to save as a PNG. Not JPEG, or any of the other options you are giving us. I'm feeling very frustrated right now.

[D Fosse]

There is actually a Photoshop bug/problem here, but it's not the one you think. The bug is that if you Save As PNG, the color profile is stripped. That's a problem whether it's intended for screen or print. But with Save As, the ppi number is preserved.

[KER77]

D Fosse, this is incorrect. The current Photoshop has a problem updating the metadata with the correct PPI (Metadata reads DPI). I just reduced a 300 PPI TIFF down to 144 PPI and performed a Save as PNG and, when you review this file's metadata, it still reads 300 PPI for XResolution and YResolution fields. However, if you place the newly created 144 PPI file into Illustrator and Export as PNG, you actually get a 144 PPI image with correctly stated metadata. Adobe needs to get their crap together when it comes to consistency between their apps (the list is long) Also, because of increasing resolution of displays beyond 72 PPI, PPI IS RELEVANT for the web. I generate 2X images all the time so they look good on both retina and non-retina displays (laptops, phones, & tablets). Incidentally, the color profile is not stripped when you use Save As PNG in Photoshop. My downresed TIFF maintained its Adobe RGB (1998) the enire time.

[D Fosse]

Anything other than sRGB can be embedded in a PNG. But not sRGB. That's the bug. In a PNG, the profile you usually need is of course sRGB.

All web browsers, photo viewers etc, automatically scale up images 2x when they detect a retina/4K screen. This is the current industry standard for all consumer-oriented applications. This confuses a lot of people who can't understand why Photoshop does not do this, but still displays accurately.

Unless the website is coded especially for 2x images. Then you upload two versions of every image, and the browser loads the appropriate version depending on what screen it detects.

So no, ppi still doesn't apply on the web. Screen size will always be determined by the screen pixel density. And Export/Save For Web still strip the resolution metadata altogether. A file out of Export does not have a ppi at all. Not 72, not 144, not 300, not anything. It's just pixels.

If you see a ppi number, it's because the application opening the file assigns a default value. Photshop, for instance, will assign 72. Most Microsoft apps will assign 96.

[KER77]

Having been in this industry from the beginning when resolution was always referred to as DPI or PPI, I had to update my understanding regarding screen image resolution (recently—since my post above). My past erroneous understandng in which screen image resolution was the same as pixel density has been corrected. Today, I now know screen image resolution means total number of pixels (i.e. the number of hortizonal pixels multiplied by the number of vertical pixels).That's it, plain and simple and pixel density means nothing on screen. I guess I was thinking of higher screen resolutions devices like Retina displays, phones and tablets as digital printers. However, because of background pixel scaling technology such as Apple's points measurement system and Android's device-independent pixels (DP) measurement system, pixels remain the same size no matter the device. Here's an online article that really helped me see the light of day on this issue: https://blog.fluidui.com/designing-for-mobile-101-pixels-points-and-resolutions/ And, this screen alone did it for me:

So, this is my long answer to say I agree with you regarding screen image resolution and why it's important to provide images for websites and HTML-based e-mails at twice the resolution (i.e. twice the pixel dimensions) so they look good on most higher resolution displays.

Regarding the stripping out of metadata, while pixel density is irrelevant metadata for on-screen use, it would be very helpful if PhotoShop would not strip out pixel dimension metadata for exported PNGs. I use an alternative Finder called Path Finder and it enables me to quickly view file metadata without having to open the file in Photoshop (kind of like QuickLook for metadata)—very helpful.

[jeremierousseau]

Allow me to up this message. 
I have encounter the exact same problem. I like to work with artboard to have the whole set of variants of my document, and the only solution I have is export... so for me it a real issue and must be considere as a bug. I hope it will be corrected soon.

[Test Screen Name]

It's not a bug because it's working as designed. Export is made to save for web. Only. Web graphics don't need a resolution (ppi). Never. So, it's all good. So far as Adobe are concerned anyway.

[jeremierousseau]

ok then how it's possible to export for print ? I know web didn't need ppi, so why changing this parameter who only concern print ? 

[D Fosse]

The normal output method in Photoshop is Save As, or Save a Copy.

File formats that don't support all current properties of the file (typically jpeg, png) are under Save a Copy. This keeps the original file open so you can save it separately without losing data.

[Test Screen Name]

You use "Save As". This has been said many times in replies. Except that Adobe have changed it for us. If Save As does not show PNG, you now have to use "Save A Copy". I don't say this is a good change.

[jeremierousseau]

it didn't work with artboard