Edit: I was able to make the output look a little bit better (not perfect). For anyone finding this from web searches, here's what I did:
To remove the hairlines I used the X-4 PDF settings.
The opaque->transparent gradient was not saving properly. I realised that using a solid black->white gradient as a transparency mask achieved a very similar result. This looked much better when saved as a PDF.
I realise now that making vector PDFs is just as much about what objects comprise the graphic as what the final image looks like.
I have a vector graphic, produces in Adobe Illustrator CS6, which I am having some trouble saving. More specifically, there is a layer with a gradient that fades from a solid colour to transparent.
What settings should I be using to save this?
Ideally I would have it look roughly the same as I see it when editing. I understand that colour profiles will inevitably vary from machine-to-machine, but it would be nice to simultaneously have the proper gradient and no hairlines. If all else fails I will just rasterise the image, I'd rather not do this though.
NOTE: This graphic will be used in an academic paper, which will be uploaded to an online repository. Hence I cannot have separate print and web versions. Some readers will be viewing it digitally, whilst some will be printing it.