The difference is even more obvious when we use an example that has an even brighter light source, like the sun:
The HDRI, however, makes nice sharp shadows and plenty of juicy contrast as we expect from those bright fluorescent light bulbs. JPG vs HDRI used to light a scene (JPG was brightened to make the comparison more even)Īs you can see, the JPG produces flat and unrealistic lighting. Here’s a simple scene lit using the JPG and the HDRI: This means that when you use the image to light a 3D scene, the light bulb will emit more light. It knows that the light bulb is much brighter than the rectangular area around it, which in the JPG version is just one solid colour. This is a neat trick, but what’s important to realize is that the HDR file stores the brightness of the light bulb correctly. In an HDRI however, the maximum brightness is practically infinite, which allows the actual fluorescent light bulbs to become visible when you darken the image.
This is because the maximum brightness of any pixel in a JPG image is 255. To illustrate the difference between a JPG and an HDR file, all we need to do is play with the brightness:Īs you can see, the JPG on the left has absolutely no detail in the brighter parts, the entire rectangle is a single solid colour. Luckily, there are several formats that can do this, the most common of which has the extension “.hdr”. If you want to light a 3D scene using an image, what you really need is a format that can store more than just 8 bits of data per channel so that you can have a much larger range of brightness. The problem with LDR images is that they are limited to a relatively small range of brightness, from 0 to 255, which is not actually all that much. An example of an LDR image is a JPG file. They store 8 bits of data for each of the red, green and blue channels for every pixel. Most photos and images in general are what I call “LDR” images, or Low Dynamic Range images.
“Dynamic range” is the measurement of how much brightness information is contained in an image, so a “high dynamic range” image is an image that has a very large range of brightness, more than you can see on your screen in one go actually. “HDRI” stands for High Dynamic Range Image. *An HDRI is a panoramic photograph that covers the entire field of vision and contains a large amount of data (typically 32 bits per pixel per channel) which can be used to emit light into a CG scene.* If you’re already confident that you know what an HDRI actually is, scroll down to the “Creating an HDRI” section. This is by no means the only way to make an HDRI, but it is a good introduction to the process.īy the end of this tutorial, you’ll have made your very own 360º HDR environment map that can be used to light a 3D scene.īuckle your seat belts boys and girls, because this is gonna be a long one!īefore we actually get into making anything, it’s important to thoroughly understand what it is that we’re doing, and demystify some of the confusion around the subject. I’ve been making HDRIs for a couple of years now, so I hope I can save you some time and experimentation. One mistake like using the wrong focal length or choosing a slow shutter speed can mean all your time has been wasted and you’ll have to start all over again. Not only do they provide accurate lighting, but they can be seen in the background and in reflections, which makes them all the more immersive.Ĭreating a high quality HDRI from scratch is quite a complicated task that requires very specific equipment and a meticulous workflow. They are essentially snapshots of the real world that contain exquisitely detailed lighting information, which can transport your bland CG objects into realistic virtual environments. There is no easier or quicker way to light a CG scene than to use an HDRI. You can find the original on his personal website, Adaptive Samples.Ī simple 3D scene that was lit using only the HDRI above (no additional lamps). The tutorial has been republished with Greg’s permission. He then covers all the steps required to process them.
FIXING SEAMS IN PTGUI PRO SOFTWARE
In this tutorial, Greg explains the theory behind HDR Environment maps and the equipment and software necessary to capture them.
FIXING SEAMS IN PTGUI PRO CODE
If you need a beautiful map, have a look! Sketchfab members get a 25% discount by using offer code “sketchfab”. Greg Zaal has been in the business of creating and selling such maps for several years on HDRI Haven. But what exactly is a HDR environment map? And how can you create your own?
FIXING SEAMS IN PTGUI PRO PRO
PRO and Business members can upload their own maps too. You can use HDR environment maps to light your scene - we provide a long list of environments for free.
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