Hdr

[schwanz583]

I know this might sound dumb to some of you, but I am new to photography and don't know what HDR is.. The pic's I look at that say they are "HDR" look amazing. Just wondering if anyone could explain what it is so maybe I can figure out how to mess around with it in photoshop. Thanks guys

[dmcantrell]

HDR = high dynamic range. The digital camera can only capture a finite range of tones. Think about a landscape shot where the sky is properly exposed but the foreground is dark and vice versa.

You can take a set of images, bracketing the exposure and then use some software to "stack" the exposures together to make one image that has a much higher dynamic range.

[arich]

I really like this tutorial on it Bonus Tutorial: HDR | D-Town TV

[Colyn]

Originally Posted by dmcantrell

HDR = high dynamic range. The digital camera can only capture a finite range of tones. Think about a landscape shot where the sky is properly exposed but the foreground is dark and vice versa.

You can take a set of images, bracketing the exposure and then use some software to "stack" the exposures together to make one image that has a much higher dynamic range.

Film cameras are also restricted in their range.

HRD got its start in the early days of film and has been adapted for digital.

[dmcantrell]

Ah, good to know Colyn -- thanks for the clarification. I did not know that, but now that you mention it, it makes sense. Physics is physics.

[Colyn]

Originally Posted by dmcantrell

Ah, good to know Colyn -- thanks for the clarification. I did not know that, but now that you mention it, it makes sense. Physics is physics.

Back in the 70's when I was a Navy photographer we used it a few times to bring out more detail in recon photos but it's use goes back before the Civil war..

I've seen a few pre-WWII photos that looked like they were hdr..

[brad]

The human eye can distinguish 30 or more stops of contrast in a scene.

Film is can distinguish 10-15.

Digital is about 5 or 6.


HDR is about increasing the stops of contrast to be equal to or greater than what the human eye can detect.. When done right, it can reveal hidden beauty and treasures in an image. When done wrong, it looks horribly cartoonish, noisy, and distracting.

[venchka]

Done correctly, exposure blending (a.k.a. HDR) is invisible.

Folks who label photos HDR and make them look "amazing" are merely indulging in the Fad du Jour.

[Wil_Bloodworth]

Originally Posted by brad

The human eye can distinguish 30 or more stops of contrast in a scene.

That is not entirely accurate. The human eye can, at any given point in time, only detect approximately 13.3 stops (a contrast ratio of 10,000:1) of EV. However, the human eye can adjust to its surroundings and adapt. It can adjust to very bright scenes and to very dark scenes... but not at the same time. The total perceivable contrast ratio of the human eye through all possible scenes is approximately 10,000,000:1.

Formulas: 2^EV = the contrast ratio. Going the other way, EV range = (roughly) 3.32 * log_10(contrast ratio).

For example, as I said above, at any given moment in time, the human eye can detect a contrast ratio of 10,000:1. So, 3.32 * log_10(10,000) = 13.28 stops of light (i.e. EV) for ye good 'ole human eye. However, as said above, the human eye can adapt to a total of 23.24 stops... but again, not at one point in time... which is what we're all talking about when taking photographs.

Originally Posted by brad

Film is can distinguish 10-15.

Off by about two. All films can get to about 8 EVs. The best-of-the-best-of-the-best can get to almost 13. They pretty much start to taper off linearly from 8 EVs to around 9.25 and logarithmically after that.

Originally Posted by brad

Digital is about 5 or 6.

A long time ago perhaps. In or around 2007, the bottom end CCD/CMOS sensor could detect 8 EVs of contrast. The best, around 11 EVs. Today, it's slightly improved... through software trickery and better hardware in general.

Originally Posted by brad

HDR is about increasing the stops of contrast.... When done wrong, it looks horribly cartoonish, noisy, and distracting.

Originally Posted by venchka

Done correctly, exposure blending (a.k.a. HDR) is invisible.

Say it with me, "Photography is art". There is no right/correct or wrong/incorrect! Just because one does not like the art another person creates does not make it wrong/incorrect.

Originally Posted by venchka

Folks who label photos HDR and make them look "amazing" are merely indulging in the Fad du Jour.

Then again, it's possible they are just embracing a very old photographic technique and enjoying yet another awesome, and currently popular, aspect of photography!

I'm so tired of the whiny arguments about HDR. It's freakin' ART!

- Wil

[Tom]

Say it with me, "Photography is art". There is no right/correct or wrong/incorrect!

There sure is a wrong way. Look at some crappy HDR.

[arich]

Originally Posted by venchka

Done correctly, exposure blending (a.k.a. HDR) is invisible.

Folks who label photos HDR and make them look "amazing" are merely indulging in the Fad du Jour.

That's like saying that artists who paint in the cubist style are just copying picasso and trying to look cool.

[ext237]

Is it up to the photographer to define what should be considered junk photography -- or the patron?

There's a lot of well composed black an white prints sitting in forgotton boxes. And there's a lot of over-baked HDR hanging on walls and showing up in popular magazines.

I compare it to velvet Elvis. Some liked it, some didn't, but someone made a lot of money making that 'art' available to the market.

Sometimes when this arguement fires up, I like to ask th HDR haters how many photos they have sold that wasn't weddings or seniors. Most have never sold an art photo to the general public -- but insist they know art better than HDR photographers.

[jeffclow]

HDR - like photography - is such a subjective hobby. The purist often will "say" that hdr is not really photography. But then, is using a filter not really photography? Is making a flowing river look dreamy with a long exposure not really photography?

I'm with Wil on this one - photography is art and none of us can say what is correct, incorrect, right or wrong.

And - full disclosure - I've sold my hdr images as stock shots via Getty (and others) many, many times. In fact, my first newspaper cover shot and my first worldwide ad campaign shot were both hdr images. So, I'm probably biased.