There are 2 types of stereoscopic 3d views in SM3dLand.

[cyberninja45]

In the latest Iwata ask for SM3dLand on the 3ds, there seem to talk about the option to change the focus of the camera in the game. See bolded text

 

From Iwata asks:

"Hayashida: The Nintendo 3DS system's 3D is good at making it look as if there is a world deep beyond the screen, so that is what we made from the start. With images that have lots of depth, there's a big discrepancy between the images sent to the right and left eyes. With a big difference like that, if you don't play holding the system directly in front of you, there's a big possibility that the images will look distorted. With a normal game, that isn't a problem, but people move their bodies when they play action games.

Iwata: The distance Mario jumps won't change if you move the controller, but you do this (moving his body) anyway. It isn't a Super Mario game if it doesn't make you do that! (laughs)

Hayashida: That's right. A good action game makes you move your body. But it's a problem if that distorts the visuals. Then Miyamoto-san said that Mario Kart 7 doesn't get blurry. I took a look, and it really didn't. I wondered why and came to understand it was because the player's kart was placed in a location where there is no binocular parallax. While driving, the players are looking at their own kart, so it doesn't look blurry. So what will people be looking at in Super Mario 3D Land?

Iwata: Mario, of course.

Hayashida: Exactly. It's Mario. We call that place where there is no disparity between the left and right eyes the reference plane. We thought we would adjust the reference plane to Mario, so he would be less likely to blur. That gave birth to the Recommended View.

Iwata: That change came in when the game was nearly complete. I was surprised to hear that your team reworked the viewpoint this late in production.

Hayashida: We'd passed one month left at that point. (laughs) About 80 percent of people responded that the Normal View made it more comfortable. But about 10 or 20 percent said that it was better before. So we thought we would leave the previous view, and that became Deep View. You can change between the two views with the +Control Pad.

Iwata: How about you, Motokura-san?

Motokura: Design-wise, more data makes it easier to generate stereoscopy, but the eye may get tired easier. We cut down on this game's density and made easy-to-grasp graphics, so Normal View was welcome.

Hayashida: Actually, Motokura-san had suggested making Mario the reference plane toward the beginning of development, but when we did that, things popped out too much. So we gave up on it once.

Iwata: When Mario that is the reference is at the reference plane, anything in front of him would pop out, so without a significant amount of adjustment, your eyes would tend to get more tired.

Hayashida: That's right. But up till the very end, I kept hearing about how they had done it with Mario Kart 7. By weakening the strength of stereoscopy and changing the camera, things stopped leaping out too much."

 

http://iwataasks.nintendo.com/interviews/#/3ds/super-mario-3d-land/0/3  (Don't read the rest if you don't like spoilers)

So it looks like you have the option where the 3d looks really deep,( the type where the entire world, including Mario, looks like its deep inside the screen) and a Normal view where Mario position is on the same plane as the screen itself. I think. So in other words the normal view is the type where the 3d is more comfortable no matter where the slider is on the 3ds, but less impressive. And deep view looks more impressive( the type where it looks like a world is behind the screen), but needs to be more adjusted to your eyes. At least thats how I think it is. I wonder what type of view the ehop trailers are. I am guessing it was normal view.

To put it more simply:

Normal view: for 3d viewing noobs

Deep view: For 3d viewing veterans

 

Also for 3ds owners, I would like to asks what kind of 3d viewer are you. Were you the type where you could have saw the 3d right away at full blast with no problems, the type where it took awhile to get adjusted, the type that can only play just below full blast/ half way/ just above 2d? Or you just can't stand 3d at all.