edge-on lines

I thought of that and tried zooming in and out. Nothing. If my camera is selected, I can see the edge-on line of the video background layer but it seems to be a function of the angle of view lines. The font layer is just invisible from the edges.
P

Jay! It's been a while! Thanks for responding. I know I can use perspective to get an angle on the layers and see them but, at least in the tutorial I'm doing, they show a bright, white line that indicates the position of the layers when you're in the top, bottom, left or right views. I don't have them. I looked them up in the Motion manual and they're called edge-on lines. The manual names them and says why they're there (to help one see the position of layers in views when the layers, being infinitesimally thin, would not be technically be visible) but it doesn't say anything about turning them on or off. So, my question to you, or to anyone is, do you see edge-on lines when you're looking at layers from top, bottom, left or right or do you have to use perspective to see your layers?

@Andy,
Thanks for responding! Like I said, I'm just beginning to learn Motion so, off hand, I couldn't answer whether I had any lights on. If I did it would have been by accident since I'm just at the point of applying the two layers - video and text - and then looking at them using the various camera angles. Just in case I'd messed something up and added lights I tried the OPT+L keys but nothing happened. I still don't have edge-on lines. Weird ... I guess.
Thanks again for responding.
Pete

I have two displays, one set at 2569 x 1440 and the other 1920 x 1200.
The tutorial is the "Creative Cow Master Series - Stephen Smith's Moving WIth Motion: A Professional's Guide." The tutorial is specifically for Motion 4. The tutorial is not controlling my computer in any way. It's just a DVD with teaching projects and examples.
In this specific instance the tutorial called for placing two elements on the screen; a piece of video and some text. The entire project is in 3D mode. The text is offset from the video by 150 in the Z-Axis. If I look at the two elements in the perspective view I can indeed see both the video at Zero on the Z-Axis and the text at 150 on the Z-Axis. When I move to the top, bottom, left or right views, those elements disappear. The Apple Motion Manual tells me that when I move to the top, bottom, left or right views that I will see what they call edge-on lines. The manual states that edge-on lines are added by Motion to indicate the positions of screen elements that, technically have no width and would therefore be invisible when viewed edge-on. My problem is, +I don't have edge-on lines+ and I don't understand why. My screen elements are indeed invisible in the top, bottom, left or right views.
Do you or +does anybody else get edge-on lines+ in similar circumstances? If you have a some video and some text and you move to the top, bottom, left or right views, do you see those elements or do they disappear in all but the perspective view?