problem with exporting png file as 300 dpi in illustrator

[amitbana]

hello there

I am trying to export artboard as png file with a 300 dpi resolution.

I did this a Thousand times in the past, but now it's not working and illustrator exports the file in a 72 dpi resolution.

I tried again and again but illustrator continue to export in 72 dpi when I tell him to eport in 300 dpi.

what's wrong and how can I fix this problem?

thanx

[Monika Gause]

Please refer to this:

Re: PNG Problems: Illustrator 2018

[Srishti Bali]

Hi amitbana,

Please follow the steps mentioned in the below-mentioned link.

Error exporting as PNG

Hope this helps!

Regards

Srishti

[AshutoshChaturvedi · Accepted solution]

Please update to version 22.0.1 to get the fix for this issue.

Thank You.

Warm Regards,

Ashutosh Chaturvedi  | Sr. Quality Engineering Manager – Illustrator

[divafern]

@AshutoshChaturvedi I'm having this issue with Illustrator exporting 72dpi regardless of my settings, but my Adobe CC says my Illustrator is up to date. I'm currently have Illustrator 22.0.0 but I can't find 22.0.1 anywhere. I'm on a MacOs Sierra version: 10.12.6

[Cooper_John_R]

I am having this same problem using the activeDocument.exportFile() function in Adobe ExtendScript for Illustrator CS6. This is maddening because I need to automate the exporting of hundreds of .PNG files at 300dpi. Is there any solution for me other than upgrading to CC?

[Stephen_A_Marsh]

The issue is user expectation based, not with the PNG file format – which officially only supports pixels per metre.

11811 pixels per metre = 300 ppi (rounded from 299.9994 ppi).

I would suggest that you use ExifTool to batch embed the correct metadata to the output files as a second step/pass if it is missing.

You may be able to embed certain metadata via scripting, however that is beyond my current skill level.

_____________

Re: How to publish a png to 300 dpi in Photoshop

Photoshop Export/Quick Export strips the resolution metadata, as does Export/Save for Web (Legacy). Photoshop Save As will retain resolution metadata.

The official PNG specification for the PNG resolution unit is in metres (not inches). So a 300 ppi save as PNG from Photoshop would embed a value of 11811 ppm (pixels per metre). When Photoshop opens a PNG with this resolution metadata, it performs a “translation” from pixels per metre to PPI:

118.11 x 2.54 = 299.9994 ppi, rounded up to 300 ppi.

If there is no resolution metadata embedded in the file, then Photoshop defaults to 72 ppi.

Adobe Bridge does not perform the same translation, so there is a discrepancy where Bridge indicates the resolution as 72 ppi when Photoshop indicates 300 ppi. Later versions of Bridge simply show an arbitrary value of 72 ppi if there is no resolution metadata in the file. Earlier versions of Bridge, such as CS6 showed no resolution information at all for PNG files, whether they had resolution metadata or not.

Re: How to export layer files as PNG'S AT 300 DPI from photoshop?

in Photoshop CS6 when using “save as” to PNG, the resolution metadata info is written to the PNG file as per the PNG standard definition. This info may display as 72 ppi in some programs (which is a historical value now used arbitrarily as an “accepted default value”, just as 300 ppi could be considered the same):

[PNG-pHYs] PixelsPerUnitX : 2835

[PNG-pHYs] PixelsPerUnitY : 2835

[PNG-pHYs] PixelUnits : meters

(28.35 cm x 2.54 cm = 72.009 inches, rounded down to 72)

However with Photoshop CC15, using a save as results in new XMP-tiff tags being added to the PNG file, which now show up as a resolution in Adobe Bridge (even in CS6). So for a file that was 473 ppi:

[PNG-pHYs] PixelsPerUnitX : 18622

[PNG-pHYs] PixelsPerUnitY : 18622

[PNG-pHYs] PixelUnits : meters

[XMP-tiff] XResolution : 473

[XMP-tiff] YResolution : 473

[XMP-tiff] ResolutionUnit : inches

(186.22cm x 2.54cm = 472.9988 inches, rounded up to 473)

It appears that in CC2018, Photoshop is now only using the correct PNG specification tags when using the “save as” command, as it did back in CS6!

So if one wishes to add this “non standard” metadata back in so that say Adobe Bridge can show a PPI value, the following ExifTool command could be used for a 300 ppi value:

exiftool -XMP-tiff:XResolution=300 -XMP-tiff:YResolution=300 -XMP-tiff:ResolutionUnit=inches -ext .png -r 'path to file or top level folder'

It appears that Photoshop automatically translates the 11811 pixels per metre value to 300 ppi when opening a PNG file that contains the PNG-pHYs metadata into Photoshop (as a standard PNG file does not contain PPI based metadata).

Therefore there are two options if using ExifTool to change the metadata value of a file that has been exported and lacks this info:

1) Change the standard PNG-pHYs to a value that equates to 300 ppi when opened in Photoshop:

exiftool -PNG-pHYs:PixelsPerUnitX=11811 -PNG-pHYs:PixelsPerUnitX=11811 -PNG-pHYs:PixelUnits=meters -ext .png -r 'path to file or top level folder'

2) Add the non-standard TIFF resolution info, in addition to the matching PNG standard value (which may not be a great idea, Adobe have now stopped doing this, perhaps the PNG files were creating problems for other software).

Re: How do you embed resolution/scale in a png?

Using export/save for web strips some or all metadata (even if S4W is set to retain metadata)…

In CC2018 – Save As PNG results in the following key metadata values being set, which are not included in the other various export options (my original was 288ppi):

[PNG-pHYs]      PixelsPerUnitX     :    11339

[PNG-pHYs]      PixelsPerUnitY     :    11339

[PNG-pHYs]      PixelUnits         :    meters

(Reported via ExifTool)

PNG PhysicalPixel Tags

11.8. Physical Pixel Dimensions (pHYs)

4.2.4.2. pHYs Physical pixel dimensions

So a value of 113.39 (CM) x 2.54 (Metric Inch Conversion) = 288 ppi

The PNG specification works in a unit value of metres. Photoshop apparently translates the embedded PNG-pHYs data into PPI when opening the file (even if rulers are set to say CM).

There appears to be some rounding up, for 288 ppi in CM = 113.386 or 113.39

The ExifTool command to change from say 288 ppi (11339) to 144 ppi (5670) =

exiftool -PixelsPerUnitX=5670 -PixelsPerUnitY=5670 -PixelUnits=meters 'path to file here'

So the above command could be used to re-embed the required metadata into PNG files exported from Photoshop, without needing to re-open and re-save the PNG files.

Note: There were non-standard metadata writing changes in CC2015 which have been removed in CC2018:

Photoshop CS6 vs CC2015 PNG Resolution & Unit

Photoshop CS6 vs CC2015 PNG Resolution & Unit

I have searched the site and come across some past discussion, however it appears that with Photoshop CC15 or later there have been some changes (hacks?)…

First in Photoshop CS6 or earlier, when using “save as” to a standard PNG info is written to the PNG file. However, this info is not visible in Adobe Bridge as a resolution:

[PNG-pHYs] PixelsPerUnitX : 18622
[PNG-pHYs] PixelsPerUnitY : 18622
[PNG-pHYs] PixelUnits : meters

However with Photoshop CC15 or later, using a save as results in these new XMP-tiff tags being added, which now show up as a resolution in Adobe Bridge (even in CS6):

[PNG-pHYs] PixelsPerUnitX : 18622
[PNG-pHYs] PixelsPerUnitY : 18622
[PNG-pHYs] PixelUnits : meters

[XMP-tiff] XResolution : 473
[XMP-tiff] YResolution : 473
[XMP-tiff] ResolutionUnit : inches

(186.22cm x 2.54cm = 472.9988 inches)

My guess is that Adobe have “extended” (hacked?) the writing of PNG files to support these “printcentric” metadata values, they are of course not written when using save for web or quick export options. For CS6, Photoshop reports the resolution as 473ppi, even though the metadata is written as 18622ppm – so I can only presume that Photoshop has always converted and rounded up the PNG-pHYs values anyway, where as Bridge did not and now bridge references the XMP-tiff values.

So this is just a “heads up” post.

[samp42855810]

I am already using version 22..0.1

[Ton Frederiks]

Try 22.1