What are the choice criteria of your camera to shoot a virtual tour?
A big majority of photographers use their camera body and will buy a fisheye lens to make a virtual tour. But if you were to buy a specific body, what qualities should be taken into account? Pixels are not the only thing to consider...
The photo equipment to shoot a virtual tour is rather different from the equipment you'll use to shoot a simple panorama. It is especially true for lenses, as we saw in the previous page and for panoramic heads, spherical or exclusive only. This equipment can evolve depending on your needs, your restrictions and the money you want to invest in it as well as on your tastes, of course. Some want to make very polished virtual tour, possibly in high resolution, indoors or outdoors, while others will rather want to shoot them into the action, hence very quickly... I only note here that a major evolution of digital cameras often goes unnoticed and yet is very convenient when you shoot on 360°x180°: the dynamic of digital sensors. It already evolved considerably and often enables, in one shot only, to shoot an entire scene without having to double certain photos in order to increase this dynamic (HDR technique). Even if windows still need to be doubled, numerous "hotspots" now fit the sensor dynamic. Precious! Let's see all this in details now...
Key points if you're a beginner...
Here are the key points to remember about the choice of the camera to make a virtual tour. The rest of this page is aimed at those who want to learn more.
First important point: have fun, because you can make virtual tours with almost any camera with changeable lenses.
The ideal is to be able to mount a fisheye lens because the shooting of a complete sphere will be noticeably quicker.
Then, it's better to have 20 Megapixels because then, with eight photos only, you can realize a quality virtual tour in which you can start zooming in.
The more recent your sensor will be, the more dynamic it will have, meaning that it will be able to save details AT THE SAME TIME in very lit up parts and in very dark parts. In 2016, NIKON bodies are always really good and are noticeably better than Canon ones on this criteria.
Any camera can do the trick, even a smartphone, theoretically. Moreover, few photographers will buy specific equipment to make virtual tours. But really, shoot a complete sphere on 180° x 360 ° with a focal about 30 mm on a smartphone can alternatively be seen as a challenge, a miracle or a punishment! The focal isn't really adapted and the dynamic of the sensor clearly insufficient compared to recent bodies', so you really need to want to enter the world records book.
Fortunately, there are solutions much more adapted! Let's now see why it's important that your body have certain characteristics and let's start with the number of pixels...
The number of pixels
Why the number of pixels it has is it so important? In classic photo, the number of pixels determines the maximum size of print possible. In virtual tour, it determines the level of zoom-in.. Because we want to get a 360° x 180° photo on screens with better and better definitions and for the display to look good and detailed, it is highly recommendable that the photo, once stitched, be big enough.
What size then? Well if you take a FULL HD screen of today as a reference, you know it displays 1920 pixels in width. Let's admit that it represents a cube side of 90° (hence with an image that is very much zoomed out) as we saw in the previous page, then our image, on 360°, must be at least this size multiplied by 4 hence about 8000 pixels of width. But with this image size and on a standard screen of today, we won't be able to zoom in. For that, the image should be much wider.
Here are a few elements to help you choose:
With an 18 Mpx body, so only two photos taken with a fisheye circular lens, the stitched image will definitely be too small since only 6000 pixels wide.
With a 24 Mpx body and six photos to shoot 360°, the resulting image will be more than 15000 pixels wide and then enables to zoom nicely in the image. The immersion is then more guaranteed!
With this same body but two or three photos only, the image would just be barely sufficient.
With the new Nikon D810 and its 36 Mpx, the challenge could be taken up with three photos and if you take at least six photos, the zoom-in possibility will be very interesting.
1 - You want to shoot a life scene where you need to be very fast: better to lose a little bit of quality and shoot in three photos. Of course it will be impossible to zoom in, but the originality of the place will still give interest to this virtual tour. It is better then to have a sensor of at least 20 Mpx - (focal 4.5 mm in APS format and 8 mm in 24x36).
2 - You have all the time you need and no material restriction, then shoot the 360° in six photos with 16 Mpx and more for a great quality (zoom-in included) - (focal: 10 mm fisheye in APS and 15 or 16 mm fisheye in 24x36).
3 - You want to be able to zoom even more in the image: change focal and increase the number of photos (for instance, about twenty with a 24 mm equivalent 24x36).
Last recommendation! to go fast (in two or three photos) it is better to have at least 20 Megapixels and if you want to make a nice virtual tour very quickly, the ideal compromise is still, according to me, 6+2 photos with a full format fisheye.
But what is sensor dynamic doing in this tutorial!? Well if you've read the part about classic panorama stitching, you know that it's possible to slightly vary the exposure between two photos in order to get more dynamic between a sunny part and another one in the shadows; and I'm not even talking about the difference between indoors and outdoors at the level of the windows. This variation can be of 1/3 diaph which can represent 2 full diaphs with six photos. But here, we have one or even two strong restrictions:
We're shooting the photo on 360° so the photo has to be closed. The first and the last photo must thus have a maximum exposure difference of 1/3 diaph.
And, especially if we want to make a complete virtual tour, the six photos shot with the camera vertical must be stitched with the zenith and nadir photos. Tolerance between two consecutive photos is then almost non-existent and in practice, it is better to choose the same exposure time for all the photos so that the sky or the ceiling can be perfectly stitched. If you have the hope to shoot a scene on 360° without over or underexposed parts, it is essential to have a digital body with an excellent dynamic. Fortunately, it increased a lot in the last five years.
Of course, if you only shoot a virtual tour every once in a while, you can use the HDR technique and stitch numerous photos together but if you want to work faster, it is very convenient to take only the exact number of photos to stitch. And I'm forced to note that the more the sensor dynamic increases, and the the more the number of cases when there's no need for HDR techniques increases as well. Here are a few illustrated examples:
On old generation camera bodies, yet already equipped with 12 Mpx sensors, the dynamic to make a photo indoors, with spotlights, is insufficient: to get beautiful shadows AND beautiful highlights, you absolutely need to take two photos and HDR or the image posterizes in highlights (grey transition); it is especially ungracious!
On more recent bodies, apart from the superior number of pixels, the real asset to make a virtual tour is according to me this increased dynamic ability enabling to shoot indoors with yet a good contrast in one shot... and withoutposterization!
I tried to sum this up in the recapitulative table below, mentioning, according to the tests I made in my office with the venerable Nikon D70 and its catastrophic dynamic, sensor dynamic.
Important remark! Even if the dynamic of Canon bodies has always been superior to Nikon bodies until recently - especially, until the very nice Nikon D7200 and the amazing D610/D810 which reverted the trend - the limit between the zone correctly exposed and the overexposed zone is always "neater" with Canon, meaning that the grey stripe visible below on the left (Nikon D200) doesn't tend to appear as often with Canon as with Nikon. There's an ON/OFF side with Nikon that is unpleasant. Exposure must be very accurate when you're working in over-exposure/underdevelopment in RAW.
Important update December 2012! It seems that this defect was reduced since version 7 of Camera Raw in Photoshop CS6 and next. Indeed, the development of RAW files from the D7200 is then incredibly neat and they don't have this grey posterization anymore - ONLY by changing my version of Camera Raw!!!!
My recommendation! So, since I love the 10.5 mm Nikkor fisheye because it stitches very easily, a D7200 mounted with this lens remains one of the best solutions currently! I love it.
This website is almost entirely free and yet almost free of ads. Why? Because they look so bad! It is lucrative though, and enables many websites to keep on living. So I asked myself: what can I do? To keep on developing this website, I'm going to need a regular income just like everyone else. How can I keep on giving access to free information like I've been doing since April 2002?
And I finally found the answer: affiliation. Every time you click on a link from this site to one of my partners' shops, they know you've been referred by me and give me a small percentage on your purchase, be it something I recommend on my website or anything else. Remember to use my links when you shop on these sites! It doesn't cost you anything and it's a win-win deal – for me, them, and you!