I haven't seen it so can't comment on it but the photo does look like real red, something I have not seen before other than as a stripe.

Here is a link that might be useful: Rebecca

I have Rebecca, new to me this spring. I had two blooms on it so far. I would not call the color a true red. Its more like a magenta red. On the link that buyorsell posted, the pics with the more purple hue is pretty accurate. However, it could be that as the plant matures, the blooms end up more scarlet, I don't know.

That second photo down looks tomato red to me on my monitor. I doubt it is accurate.

I saw a Rebecca in bloom at Joy Creek Nurseries this July, and there it was (to me) a very true red, as in fire engine red -- really strikingly different from the color of any other clematis I've seen so far. No purple tinge at all in the one I saw.

Well, I won't be driving out there to see it. Give me really bad customer service once and I'll go back but twice means they can kiss my .........

Saw one today at a different garden center. It was a lot redder than Niobe or any other "red" that I've ever seen but it wasn't tomato red like the picture on the big tag hanging on the stake. It was in a shaded sales area so I don't know if it would be redder in full sun or not. There were about a dozen of them but only one open flower.