Frequently asked questions - General
Click one of the questions to check the details:
What does the term HDR photography mean? What are the benefits and uses of HDR photography?
HDR photography stands for High Dynamic Range (HDR) photography. HDR photography
is a photography technique that allows you to capture a wider range of light and
colors in a scene than what normal digital imaging techniques can achieve. This
is done by combining three or more photos of the same scene with different exposures
instead of just one photo. The advantage of HDR photos lies in obtaining a photo
that keeps details and reproduces vivid colors in both light and dark areas simultaneously.
What is HDR Photo Pro?
Everimaging's HDR Photo Pro is an all-in-one High Dynamic Range (HDR) photographic application designed to helping you rapidly and easily produce great photographic images.
What is HDR Darkroom?
HDR Darkroom is a revolutionary HDR software used to help you create gorgeous HDR
photos with minimal effort.
What is Tone Mapping?
Usually, the first step of HDR software is to merge photos with different exposures
into a 32-bit float pointing radiance map, which is also called a digital HDR negative.
Compared with a conventional 8-bit image format like JPEG, BMP, 32-bit float pointing
format has a much wider range to record any small or large values and thus can accurately
record the full dynamic range of the real world. However, 32-bit float pointing
value cannot be displayed or printed in current 8-bit monitors or printer. To users
they are just meaningless numerical numbers no matter how accurate they are. Tone
Mapping is the technology used to convert 32-bit float pointing format to 8-bit
images for display or print, which captures our visual experience in the process
of conversion. Since 32-bit float pointing radiance map is also called digital HDR
negative, Tone Mapping can be regarded as the corresponding development process
of the conventional photography workflow. Tone Mapping is the most important part
of the HDR software, therefore, in order to determine whether a HDR software is
good you must first look at the quality of the Tone Mapping.
What is Ghost Reduction?
Moving subjects are one of the biggest obstacles to create high-quality HDR photos, which may be capatured at different positions when shooting mutilple photos for the same scene. Thus, moving subjects will be shown on the final merged HDR photos as ghost-like effect. We developed “ghost-reduction” technique to intelligently reduce the ghost-like effect caused by moving subjects and ensure the amazing HDR photo capture.
What is Alignment?
It’s not esay to ensure camera is complete static when taking three or more photos simultaneously in seconds, due to some unstable factors like shooting environment and camera shake will naturally cause shooting subjects shift, rotation or deformation. Therefore, it is necessary to completely align every pixel coordiantes for the purpose of clearly defined HDR scene.
What is the difference between global tone mapping and local tone mapping?
Global tone mapping technologies refer to techniques that use a monotonic mapping
curve to independently transfer real-world lighting and color to your display. These
technologies are relatively simple and fast. However, these technologies cannot
give impressive results. In comparison, Local tone mapping technologies consider
pixel neighborhood information in the mapping processing for each individual pixel,
which simulates the adaptive and local property of human vision system. Thus, Local
tone mapping technologies can achieve much better results. However, this will take
longer for your computer to process. In HDR software, global tone mapping technologies
are usually used for fast preview of images, while local tone mapping technologies
are used to prepare the final results for display or printing.
How many photos are needed to make HDR photos?
In order to acquire high quality HDR photos, it is strongly recommended to have
at least three photos. In theory, the more photos you shoot and use, the better
quality of the HDR photos you can create. In practice, we have found that there
is no big difference if you use more than 5 photos with different exposures.
What is the ideal exposure spacing?
It depends on the scene. For many outdoor scenes, three exposures spaced one or
two EVs apart are usually sufficient. However, for an interior scene with an outside
view on a sunny day the dynamic range can be extremely high. As for exposure spacing
in this situation, an increment of 1 or 2 E.V. is generally recommended.
Will HDR Photo Pro or HDR Darkroom work on Windows Vista and Windows 7?
Yes. The current versions of HDR Photo Pro and HDR Darkroom have already exhibited strong performance
on both Windows Vista and Windows 7 for both 32-bit and 64-bit system.