Lines appearing in PNG after export from Indesign

[multitalented_hearted16B8]

Hi there,

we have an issue with the PNG export of InDesign.

There are horizontal lines appearing in a drop-shadow after the export.

We placed a native PSD image containing multiple layers and transparency.

When we export the InDesign page(s) into a PNG we got random lines in the drop-shadow.

The lines are randomly, there are no further objects which could cause this lines.

The layouts contains guidelines but the are set to not printable. And the lines have a different position.

The lines change position if we use different resolutions for the PNG export.

Here is an example how it looks like after an InDesign-PNG export: "png-export-screenshot"

If we use a different exports e.g. *.jpg or *.pdf we don´t get those lines.

Even if we export a *.pdf which is further transformed to a *.tif via Photoshop with a transparent background we don´t have this lines in the shadow.

We tested this issue with:

InDesign CC2022 v.17.4.2.77

InDesign CC2023 v.18.4.0.56

Did anyone had a similar issue?

Or any idea what we could try, else?

Best reagrds

Chris

[Willi Adelberger]

You will get a better quality if you export the INDD into PDF/X-4, open that in Photoshop and make the PNG from there. 

[multitalented_hearted16B8]

Well, I forgot to add an important information.

We tested this with Adobe InDesign Desktop applications but we have this issue with our InDesign Server.

The exports are triggered by using java-script to export PNG or PDF.

A workaround with Photoshop is not an option for us, because we are in a systemenvironment (censhare).

The effect with the lines comes only with the PNG export, no matter if InDesign-Server or InDesign-Desktop.

[rob day]

There are know quality problems when a page that includes placed images or bitmap effects are exported to the JPEG or PNG image formats. In those cases an export to PDF then to Photoshop results in the highest quality image.

A workaround with Photoshop is not an option for us... The exports are triggered by using java-script to export PNG or PDF.

When you say you export via a script does that mean Photoshop is not available on the system and can’t be activated? I use a pair of Javascripts to export JPEG and PNG via PDF to Photoshop using a Bridgetalk object, which you are welcome to try. They can be downloaded here:

https://shared-assets.adobe.com/link/f0f122b9-4d2d-4dc9-76a7-2cca55143c35

The PNG dialog:

The exported PNG:

[multitalented_hearted16B8]

Hi Rob,

thanks for your answer.

I´ll try to answer your question pretty quick.

The whole process will be triggered by an asset-event, all the rest will happen automatically.

Asset reaches a state and triggers an Adobe InDesign-Server to use a js-script to export PNGs and also PDFs will be exported.

Adobe Photoshop can be used in censhare by users (installed locally) but not in automated processes (serverside). In this case we could use an ImageMagicks, which we already do to create *.tiffs from the exported PDFs.

But we really would like to use InDesigns PNG-export to generate the PNGs instead of unsing the PDF-workaround.

The idea of Bridgetalk sounds nice, but unfortunately we do not use a CreativeCloud environtment here. It´s only the InDesign- and the Image-Magicks-server in a censhare-system environment.