Portal/Chamber 15: Difference between revisions

In the first room, there isn't much you can do except to portal yourself forward (instead of walking) and executing promptly and perfectly.  Get the orange portal on the high extended panel as soon as possible.  Don't worry about exactly where you're standing, put the blue portal under your feet immediately.  As soon as you pop out of the orange portal, move the blue portal to where you're going to land.  Don't try to get the blue portal in the right place so that you can pass through it twice without moving it; most people will find it easier and quicker to move the portal in mid-fling.

The second room can be frustrating.  Use a portal on the wall and one under your feet (in the first room) to get as far into the room as possible with the minimum of walking.  Immediately place the portals to send the pellet into the room with the receiver.  Stand close to the emancipation grid, but be careful not to touch it.  Watch the pellet go into the first portal and as soon as it does move through the grid.  Place the portals first over the red glow and then on the back wall.  There are two ways to make sure that the pellet hits the receiver.  Either make sure that the portal from which the pellet emerges is exactly over the middle of the opening to the next room (or at some other well-known position) and get the portal on the back wall to match this position.  Or, look up so that you can see the pellet passing over your head, judge where on the back wall it will hit and place the portal there.  This is all a lot to do in the short time it takes the first pellet to complete its journey.  If you miss, you have to wait for the first pellet to dissipate and the second to be launched.  Argh!  When the pellet reaches the receiver and the platform begins to lower you should already be back out in the main room and clear of the emancipation grid.  As soon as you can shoot a portal through the gap above the platform, do so.  Put the other portal in the wall nearby and go through without waiting to ride the platform.

Again, portal yourself forward into the third room instead of walking.  Portal yourself up into the side room, near the opening.  Keep track of your orientation as you do this because you need to quickly turn and shoot a portal through the opening back into the main room to land on the high extended panel.  Now you have to walk to the small pit, place the other portal at the bottom, fall in, move the portal as you fall and double-fling over the barrier.  Practice until you can get this right just about every time.  Having got past the first barrier, ''do not'' play the pellet game; this and riding the moving platforms takes too long.  Instead, use [[Portal/Tips and advanced techniques#Peek-a-portal|peek-a-portal]] to get through the corridor without starting the platform.  Put the blue portal to the left of the opening to the corridor and the first orange portal on the wall at the end of the first section of the corridor as far to the left and as high as possible.  Putting it to the left gives you the maximum distance to the next position of the portal which gives you more time to pull back after shooting.  Turn to the left and move sideways into the blue portal just until you see the glow of the edge change from blue to orange.  This means that you are standing in the orange portal and looking down the second section of the corridor.  Shoot the second orange portal at the wall at the far end (towards the right is better for the reason just explained) and ''immediately'' strafe left, through the existing orange portal before it closes, so that you are back in the third room.  This all needs to be repeated to pass through the third section of the corridor.  This time, turn to your right and slide left-ward through the blue portal until the glow changes to orange.  Fire your third orange portal at the floor of the fourth room and, again, ''immediately'' strafe, this time to the right, to return to the third room before the orange portal lands and closes the one you were standing in.  Now simply go completely through the blue portal and pop out of the orange one in the fourth room.  Where you put the portal in the fourth room turns out to be important.  If you get it in the wrong place, you pop out in the path of the energy pellet.  You also need to reorient yourself quickly to execute the final fling to the exit promptly (see below).  So, experiment a bit and find out what works best for you.

In the fourth room, none of the equipment is necessary; you can just fling up onto the exit platform.  Place the blue portal anywhere on the ceiling in a clear area (clear of the pellet and any obstruction underneath it on the floor).  Place the orange portal sideways right next to the grating under the platform by the exit area and fall through, looking straight down.  As you fall, move the blue portal to the floor.  As you fly up again through the orange portal, strafe and turn to land on the platform and walk out.