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Old 03-30-2013, 10:43 AM   #812
oot & aboot
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Joined: Jun 2003
Location: 8000ft.
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Originally Posted by Dorzok View Post
question. if it's not cartoon-y how do you tell if it's HDR? seriously. and is there a differences between pics shot in HDR and pics that were post processed to look HDR?
One other "technical note" that might help:

EV stands of "exposure value". It is an interval of a camera's photographic exposure scale.

Outdoors with natural light - there is/are about 15 EVs visible.
The average point'n'shoot camera can only capture 5 or 6 EVs. (hence you get blown out skies when you shoot shadows or blacked shadows when you shoot skies)
An expensive DSLR type camera can capture perhaps 7-9 EVs. (hence why a good camera's photos look so much better than point'n'shoot!)

Say you had a really nice DSLR which could do 9 EVs.
By taking a photo at -2 EV, 0 EV and then +2 EV, you are now seeing 13 out of 15 visible EVs in natural light (you are adding 2 EVs below the normal photo and then adding 2EVs above the normal photo).
Pretty impressive and close to what you see when you are standing there - 13 versus 15.

This was the original intent of HDR. That said, it is difficult to pull exactly the data you want from each of the images (trying to get EV -1 and -2 and EV +10 and +11 exclusive data added into your EV 1-9 photo).
The HDR processing is supposed to allow you to pull the data from the 3 images and merge them. Because of the overlap in data that is visible in all 3 images, you often end up with "pop" because items in your image have 3 values that are all valid. How the end user chooses to merge (or process) this overlapping data is what determine's one's personal HDR style (the most famous perhaps of which was Ansel Adams way back when - and Trey Ratcliff in the internet age (and what most HDR images these days are styled after).

Ansel Adams was amazing in that he did HDR the "old fashioned way" with film!

Trey Ratcliff's style - made famous through his "Stuck in Customs" website

This is why when you look through this thread you can see many images that are very similar in style - they are using the same software/filters (i.e. algorithms) to merge the overlapping data.. and hence end up with something similar.

The same goes for tone-mapping (i.e. "coloring" a single image to give a similar style).

Clear as mud?

p.s. if you are interested in how Ansel Adams managed to do HDR pre-existence of computers.. you might enjoy this article:

Geek screwed with this post 03-30-2013 at 10:51 AM
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