Bracket and Blend

[curelightwounds]

I've noticed that a lot of people ask about what to do with blown out or whited out skies. This can be particularly troublesome when shooting indoors. Depress the exposure and you catch the sky but underexpose the interior. Increase the exposure and you catch the interior but blow out the sky. Try to get the middle ground and you do a poor job of both.

So what do you do? You're trapped with poor exposures on either end and just bad in the middle.

Back in the day when people bought rolls of cellulose and bottles of acids and bases to develop photographs there was a simple solution and that was a lot of dark room magic that I don't have the slightest clue how to do.

Fortunately computers have made that unnecessary.

To do this you need three main things:
1) a tripod
2) a camera that allows you to control the EV
3) a subject that can remain perfectly still

The first step is to bracket your photo.

The bracket:



In bracketing, take your first photo at the recommended exposure level. Then take two other shots at least one stop away from on both sides. E.g. EV: -2, 0, +2. Most SLRs should come with a bracketing function that will do this for you.

The reason for the tripod and still subject is to make sure that nothing moves. This avoids ghosting in the blending phase.

The next step is the blend. I use Photomatix, but I'm sure there are other processing programs that can do this.

In blending the highlights of your darkest exposure and the shadows of your highest exposure are added to your middle exposure. Then magic happens and you get the following.

The end result (other processing also done):

[kirbinster]

A tripod is no longer strickly necessary. Most of these programs have algorithems to find edges and mesh together pictures that don't perfectly match.

[curelightwounds]

Originally Posted by kirbinster

A tripod is no longer strickly necessary. Most of these programs have algorithems to find edges and mesh together pictures that don't perfectly match.

Which do you use? I haven't found one that can eliminate ghosting 100%. I've had a few that are pretty good, but none that I'm particularly thrilled with. If there's a good one that would save me trouble of explaining the tripod on the off chance I'm caught on an explore.

[kirbinster]

I have tried many of them, and you are correct in that they may not be 100% perfect but they are very good. Should you use a tripod - yes, is it absolutely critical - no for many shots.

[inkista]

Tripod usage mostly comes down to the shutter speeds you need for the brighter exposures for me, and how good you are at keeping the camera still in space while you take the member shots. I've trained myself to do spherical panos handheld, so I'm pretty good at it, but I still tend to carry a tripod with me a lot.

I use enfuse (via LR/Enfuse with LR3) for the fusing because I'm lazy and I don't like leaving Lightroom unless I have to, and I prefer the naturalistic look that's more of a default with enfuse. I believe LR/Enfuse uses align_image_stack for the aligning. It works pretty well for me.


Canon 50D. EF-S 18-55 f/3.5-5.6 II (non-IS kit lens). Three exposures, ±2EV. handheld.

Enfuse and align_image_stack are the same open source command line tools that Hugin uses. I know PTGui can use enfuse, but it may use its own alignment software, not sure. And I think qtpfsgui also uses align_image_stack.

The main mistake that people make with enfuse is assuming it works like HDR tonemapping; it doesn't. Enfuse isn't remapping colors--it's choosing individual pixel values from the member images. There's a Contrast/Exposure/Saturation setting window that is basically asking you to weight how a pixel is chosen for the first image: either by how high its contrast compared to the other images (i.e., focus stacking), how well-exposed it is, or how saturated it is. This is not (directly) about boosting exposure/contrast/saturation in the final image, and all three settings are relative to each other. So choosing 0,0,0 is the same as choosing 1,1,1. A lot of folks get this wrong when they play with it, slide the saturation all the way to 1.0, and then wonder why their image isn't super-saturated the way Photomatix makes it.

CS5 find edges just fine for me.

[Majik_Imaje]

Originally Posted by curelightwounds

Back in the day when people bought rolls of cellulose and bottles of acids and bases to develop photographs there was a simple solution and that was a lot of dark room magic that I don't have the slightest clue how to do.

Back in the day - In the darkroom.. .. burning & dodging were the two main skills that were used to create masterpieces.

There is one extremely famous photographer that pushed the envelope using these techniques. He is legendary for his images.

I used to be very frustrated with my work, back in the day. My images did not print with the same color saturation that I remembered seeing when I exposed the film.

Then; one day, while reading a photo book - I came across this sentence. The book went flying over my head as I was running out of the living room downstairs to the darkroom - to practice!

This was the sentence I had just read that forever changed the way I printed my photographs.

.. .." It would often take as many as 30 sheets of paper for Ansel Adams to produce one final print!! "

BURNING & DODGING !!

[curelightwounds]

Originally Posted by Majik_Imaje

.. .." It would often take as many as 30 sheets of paper for Ansel Adams to produce one final print!! "

BURNING & DODGING !!

QFT!

If I had to pay for every tweak I made on an image this hobby would have been oppressively expensive. Fortunately I don't and it's not.

I would never call what I do in post processing "engineering" a photo or "improving" a photo. Those words imply some kind of know-how and understanding of how it all fits together that I don't actually have.

I tinker. I beat the machine until something pretty comes out the other end. (Don't.) I imagine most amateurs do the same.

In the same way the printing press brought language to the people, digital cameras have done the same for photography. Just my 0.014 euros.