I have a very simple philosophy when it comes to printer driver software - put as little "strain" on it as possible. Therefore always print portrait at the driver, don't force it to do a 90 degree rotation of the image, let Photoshop or LR do the pixel processing. Similarly with color management, keep it turned off in the driver, do it upstream. Printer design engineers are less skilled at software, probably not as bad as it used to be but still IMO a good rule to go by.
Richard Southworth
A 90 degree rotation is simple math. No issues. If you always keep portrait in the driver, you add a lot of work in that you have to rotate the image in photoshop and save that file.
I’ve printed thousands of images from Lightroom and have virtually no issues which I see common place. Lightroom is doing the work, not the driver.
I have customers who purchase epson printers from me and come back with half prints, weird borders and other issues when printing from Lightroom.
A couple of minutes and they never come back with those problems. For the benefit of those reading this thread trying to find an answer to similar problems ...
First, understand when putting a paper size into the dialog box, the printer doesn’t care if your image is a portrait or a landscape oriented image. You are telling the printer what size of a piece of paper you are putting into the printer, or if a roll how wide the roll is and how long of a piece you want it to cut off, not how big this particular print is. So in the width box, you don’t put the width of your desired finished print. You put the width of the roll or the piece of paper into that box. Transposing those numbers can lead to all kinds of weird things, they seem to be hit and miss because if you put the wrong size in, but then put in another “wrong” setting they can balance themselves out.
At that point in Lightroom you can easily tell if you have the correct orientation set in the Page Setup dialog. Just look at the preview image. If the image is normal, the setting is right. If the image is sideways, it’s wrong and you need to change the orientation in Page Setup. First one below is right, will print fine. Second one ... all bets are off as to what you will get. might work, might be weird borders, might be ½ a print.