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Understanding HDR (High Dynamic Range)
2008-02-15 10:09:00 You may have notice I have been playing a lot with the HDRi (High Dynamic Range) technique later. I offer no excuse, I am playing, I just need to figure out how it works and how I might be able to use it. So here is my simple explanation of the general...
Understanding HDR (High Dynamic Range)
2008-02-15 10:09:00 You may have notice I have been playing a lot with the HDRi (High Dynamic Range) technique later. I offer no excuse, I am playing, I just need to figure out how it works and how I might be able to use it. So here is my simple explanation of the general process. Note I am using FDRTools in this example because it is easier to show what is going on (I already prefer dynamic photo, see my previous post why) Step 1, Take a set of bracketed photos, (three is a good number but you can take more) at different EV exposures. Step 2, Load those photos into software that can analyse the exposure range of each photo, it is normally necessary to align the individual photos, if you use a tripod this will not be necessary. I actually rested the camera on a wall to keep it steady so i have jumped over this step. Step 3 now create a virtual photo space with a wider range of exposure range, using a composite of all intensity recorded (ie the darks from the darkest photos, ton...
Enjoying the warmth of the sunset
2008-01-29 14:20:00 It is really clear to me that the HDRi techniques (performed here with Dynamic Photo) are ideal for taking "better" (in that they will look more closely like the lighting at the time) in low light, especially at sunrise and sunset, and the half light of artificially lights. In this example I took just three photos using the bracketing feature on my camera at 0.5 EV intervals (shown above). I also used tone adjustment (via Windows Live Photo Gallery) to "stretch" inner section of the exposure captured in the center image above(the no EV adjusted image) as a comparison. The image is still a striking sunset, but harsh, it has as very strong contrast and the colours slightly shifted, not as warm or natural.
Tone Mapping...
2007-10-11 00:42:00 Como já expliquei num post anterior, o HDR permite aumentar a gama dinâmica de uma foto combinando fotografias com diferentes exposições. Um vez obtida a imagem HDR pode ser usado o Tone Mapping para ajustarmos as cores, contraste, saturação e outros parametros da fotografia como quisermos e mais gostarmos. Como esta técnica nem sempre se adequa a uma foto ou nem sempre conseguimos obter exposições diferentes da mesma foto de forma adequada, podem também usar software para simular HDR com apenas uma foto obtendo mesmo assim bons resultados. O único senão é que se usarmos só uma foto, quase inevitavelmente o ruído na foto final ir ser maior do que na foto original... Em baixo mostro uma panorâmica á qual apliquei 2 "Tone Mapping" diferentes. A original é a foto do meio... Pôres do Sol @ Aveiro - 2007 : 5190x1470 pixels Panorâmica do pôr-do-sol com 2 "Tone Mapping" diferentes... Ver no Google Maps FOV: 130º 1/240sec at f/4,3 IS...
By: Vista Panoramica
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