A naïve observational viewpoint doesn't automatically try to correct for signal delays. In other words, the time co-ordinate is retarded.
In popular expositions of relativity you'll find things like "moving observers see each other's clocks as running slow". If you're lucky it's made clear that "see" is not the everyday, well-understood meaning, but is technical jargon that involves correcting for signal delays. Often this point will be buried, sometimes it is not mentioned at all, and sometimes expositors just get confused on this point. (Even competent ones!)
Anyway, even if it makes it clear that this isn't what you actually see, it won't tell you what you do actually see. This is unfortunate because it doesn't seem like a very esoteric fact to me that oncoming clocks run fast. Is there a good low-level exposition that covers this, and other basic phenomena of special relativity, as they naïvely appear?