You may have noticed on many virtual tours the floor is not quite complete. The floor is ‘stamped’ usually by the logo of the company creating the virtual tour or the company’s logo for whom the virtual tour was made for. This is because to put in the floor (and make your panorama really 360 x 180) is quite a difficult task and can extend the post processing time quite considerably.
A lot of companies would argue that the floor isn’t worth the post processing time but we think in many cases the floor is just as important as the rest of the virtual tour itself. If you are somewhat like us and would prefer to make your virtual tours really 360 x 180 then it is vital that the floor is included in each panorama. Through the rest of this article I will explain how to include the entire floor using a tripod and a pano head (although neither of these is completely necessary).
Take all of your photographs around the 360 degrees, then move the camera pointing vertically up to take the sky shot. Then move the camera pointing vertically down and take the shot facing the tripod, remembering not to focus on the tripod itself but the ground surrounding it. With something in your pocket such as a coin or another small object mark the ground underneath the non parallax point or as close to it as possible. Pick up both the camera and the tripod and move around (yourself included) 180 degrees, then take one step backwards with the camera and tripod in hand. On the side of the pano head you will notice you can move the camera between 0 and 90 degrees each way. Move the camera to 30 degrees facing down and then extend the back leg of the tripod so the camera is now pointing at your mark on the ground. Keep your foot on the back leg of the tripod otherwise the camera with topple over. Move your mark and take the photo.
I will run through the post processing using PTGui in mind. Other programmes such as Pano2VR have similar methods. Load up all your photographs, not including the last shot you took of the floor and stitch them together as normal. Remember to mask out the tripod in every shot, including the photo pointing vertically down. Then load up the photo of the floor. Link the images as normal if you are using HDR photography. Then go to mask. Mask absolutely everything in the image except the floor. Then go to the advanced options and go to ‘Optimizer’ and click on the advanced options. You will see a small chart with the image names running down the left hand side. You will notice ‘viewpoint’ is not checked for any of the photos. Check ‘viewpoint’ for your floor shot only. This is to tell the PTGui that your floor image is not at the non-parrallax point.
Next click on ‘Control Points’ in the advanced options at the top of the screen. Here you will be able to stitch in your floor shot. On the left hand side have the shot of the floor you took with the camera pointing vertically down. On the right hand side have the shot of the floor taken with the mark and start stitching them together using control points. To get you started you can try clicking ‘Control Points’ at the very top of the screen and scrolling down to ‘Generate control points for image X and Y’. A lot of the time PTGui with not recognise any control points but do not worry if it does not.
Once PTGui has recognised the pictures (PTGui with start placing the second control point for you), click on ‘Optimizer’ on the menu above and at the bottom click ‘Run Optimizer’. Hopefully it should come up with a message saying ‘Good’ or ‘Very Good’ if it says anything else go back and put in some more control points for each of your floor shots. You can check where you might need more control points using the ‘Preview’. You also might need to add some ‘Vertical control points’ as sometimes the floor shot can bend the panorama. Then export panorama as usual and you will then have complete 360 x 180 virtual tours.
Jasper Tupman is creative director for Virtual Tours at www.liontreevirtualtours.com. Hes specialises in creating custom 360 virtual tours.