Hey Jon,
A label or decal is a standard to do in production. To find something, please place the term “Label” in the search field (Cineversity). :o)
Perhaps more luck in the Help Content of R15 will be given with the term “decal” instead of label.
There are two ways to add a label to a bottle, directly or on a specific cylindrical object. The label directly on the bottle will show very flat, like printed on the glass—if not handled with bump or displacement.
The Cylinder around the bottle in the label area might speed up the work and helps even in some cases, if the bottle had no proper UV set up so far. The Cylinder is ver tight around the bottle, but not as close to intersect, and has typically the same resolution (mesh)—to have no intersections.
A decal/label is typically delivered with a new material, and the texture tag is set to front and “Tiling” is disabled. For a bottle cylindrical projection is certainly a good start. The Offset and Length values will help, as does the Texture Axis tool. (If the Cylinder object is used, this can be rotated or moved, which many people prefer. (The cylinder object needs to be (1. material) invisible/transparent, no spec or other channels on, then (2 Material contain the label, with no tile etc)
The top layer of such an texture sandwich is always the most right sided one. There is more in the Help Content about this.
Sometimes an “Alpha” channel needs to be fed, to get the label nicely projected. Print version (pdf again!) have often more print area than needed, to follow the needs of the print office. Nothing that your client likes to see. I will leave my “two cents” about PDFs later, but the alpha channel handling will perhaps already change your mind.
Many labels have not a perfect connection to the bottle, these little imperfections needs to be addressed. With the cylindrical object via Magnet on the mesh directly, or via bump/displacement.
A word to PDF: yes it is possible, but I do not advice that, except you know what the pdf contains. Nearly twenty years ago when Adobe got the idea to use the postscript format that was send to laser printers as the world unique language, and re-translated it to virtual prints (PDF): a world standard was born. More than often PDFs contain informations that will not help your work, perhaps it works even against you. Since ten+ years PDF can contain even multi media and 3D data. Nothing that makes your workflow more safe. Again, if you know it is just a wrapper for an image, you might have no trouble. I do not use PDF at any time in production. I trust on standard graphic formats. Tiff is certainly the most stable format I’m aware off. It is large, so I tent to use Open EXR. Photoshop if layers are needed. Other people love other formats, which is a longer story and should fit to everyones workflow of course.
The handling of color profiles in an 3rd party PDF is not simple. Etc.etc. Just my two cents.
Good luck
Sassi