When I apply a transparency to a raster image (ie. an airphoto) and export my layout in ArcGIS Pro to PDF, strange lines appear in the image (almost like the software is tiling it). If I remove the transparency, then the export is fine. I have tried adjusting the DPI during the export and printing directly to PDF, with no luck.
Has anyone else had this issue... and if so is there a fix? I am using ArcGIS Pro 2.0.1.
Thanks for the follow-up. In this particular case, graphic designers later place the map into larger kiosk layouts. They asked me to keep things vector as much as possible. Also, all of the colors in the map accord to the CMYK color scheme that they developed. If I export to PNG or JPEG, I can't set the destination colorspace to CMYK . The colors in the exported image are way off.
We'll just keep using ArcMap until this gets resolved, hopefully soon. I enjoy using Pro much more than ArcMap, especially since ArcMap doesn't use any type of anti-aliasing and I have to export to a PDF to see my layout it in a crisper view.
Here's an FAQ I just wrote up for this issue:
WHY DO I NOT SEE THIS ARTIFACT IN ARCMAP?
ArcMap does not exhibit this behavior is because the output pipeline in ArcMap DOES NOT support alpha transparency. All the layers below a partially transparent layer are already flattened and composited together into a single layer called "Image" in the PDF - so you lose the layers.
WHY DOES PRO EXPORT HAVE THIS PROBLEM?
Pro exports can natively support transparency in any layer, and because of this they run afoul of this display artifact in PDF reader when a raster layer is output that contains transparency in multiple tiles.
I ONLY HAVE ONE RASTER LAYER IN MY MAP, WHY DO I SEE THIS PROBLEM?
Keep in mind that some layers "become" raster layers when some symbology is applied (an example would be the heatmap renderer for points) even if they're not raster layers in your ArcGIS Pro map. Even a single raster layer can become multiple _tiles_ of raster layer (placed like mosaic tiles together to form the larger image). We output raster layers in multiple tiles so that we can export higher resolutions without consuming inordinate amounts of resources.
WHY DOES OUTPUT AS IMAGE CAUSE THE GRIDLINES TO DISAPPEAR?
- Exporting using "Output As Image" gets around this because it performs flattening of the transparency BEFORE we write it to the PDF (very similar to what ArcMap output did).
ARE YOU SURE THIS IS AN ISSUE IN THE DISPLAYING APPLICATION, NOT SOME PROBLEM WITH THE PDF?
- the gridlines remain the same width regardless of zoom level.
- you can print this from Acrobat and it looks fine (no gridlines).
- You can also use "Optimize PDF" and choose the flatten option (which removes transparency) and no gridlines.
- The gridlines are ONLY visible in the viewing application, and they appear to be an artifact of the way that transparency is applied to adjacent tiles in the viewing application.
- We can inspect the coordinates of each of the tiles internal to the PDF written and they are NOT overlapping.
WHAT ACTIONS ARE BEING TAKEN TO TRY TO INVESTIGATE OR MITIGATE THIS ISSUE?
After a long period of investigation, we contacted Adobe support about this some time ago. In that contact, Adobe employee Dov Isaacs had acknowledged that it the PDF is written to spec, and therefore should display without these artifacts. It is currently an open bug in the Adobe Acrobat queue.
WHAT IS THE STATUS OF THE BUG IN ADOBE'S QUEUE?
We now are waiting on some analysis or guidance from them.
We have also recently reached out through multiple channels to try and get some response on this issue, but so far have not heard any updates.
Jeremy, thanks for your explanation on this. Just one point on the above. You say that "you can print this from Acrobat and it looks fine (no gridlines).", however, this is not what we are experiencing. When we print this...the gridlines are present on the print. We don't use Adobe Acrobat as a busines, we are using Bluebeam Revu.
Thank you Jeremy for your efforts on this bug! I agree with A Zendel that exporting to an image is not a work-around since the fonts will be 'rasterized'. We will continue to use ArcMap until this is resolved for exports which include a transparency until this is resolved . Thank you again and your team for keeping us informed of your status with Adobe.
Until this is resolved properly I've found the following working around useful:
It seems like the issue is with tiling out the basemap for export when a transparency layer is set? I don't understand why ESRI doesn't just give us the option to not tile out the basemap on export until they can resolve their issue with Adobe.
Was able to figure workaround:
1) place targeted raster/basemap in a new group by right clicking layer, and reset transparency to 0% in appearance group.
2) click on new group in ToC
3) set group transparency to wanted percentage in appearance group