Photography Discussion ⇒ HDR_ how many exposures do you need?

[pop511]

Posted an article about this subject some time ago, but I thought it fun to return.
Yes I know that depending on whom you listened to and your own style of working you will take as a minimum 3 to 5 shots at perhaps 1 or 2 stops latitude difference.
Or perhaps finding your black area and exposing for that and similar exposing for the white area.
I'm lazy and always exposed using three shots at 2 stops difference. Then one day, for fun, I Thought, what would it look like if I took the -2 and the +2 only and processed that in P/S in "automate merge to HDR pro"?
In short I am stunned, especially in the blacks. Rich and finely detailed. Better than combining three exposures.
But that's me and my camera.
So what about you? Anyone tried this?
Kind Regards;

[Charles Haacker]

I have done precious little HDR. I initially turned up my nose because since much HDR I saw was instantly recognizable as such; I considered it garish and unrealistic, but over time I realized that there was HDR ...and HDR, much more reasonable. The little HDR I have done has been 3-shot, 1-stop interval. It strikes me that there should really be no good reason that 2 shots 4 stops apart wouldn't work, although I'd have to play with it. One reason I don't is that I am of the mind that "modern" sensors (last 4 or so years) have more than enough dynamic range to cover, especially if one is shooting raw. I think HDR held more of an advantage once upon a time but is becoming (or has become) obsolete, unnecessary. I have taken one of the (usually) 3 exposures and worked it in Lightroom to try to get as close to the HDR version as possible. I have felt that I got so close as to not need to have bothered with the HDR merge. I have done it with a 1" sensor Sony RX-10 (released 2013). There was to my eye only the slightest difference, the HDR version just a little richer in overall detail, and I thought the difference negligible, which is one reason I don't bother.

[PietFrancke]

I am thinking that we have a couple of factors. First is the idea that capturing the maximum Raw detail available is important (for our sensors, getting the maximum dynamic range). But second, turning the information available into the best image possible. The second (I think) is more critical (though you can never replace that which was not captured).

Turning the raw information into the best image is a combination of knowing your tools and having the ability (the taste if you will) to recognize and then emphasize that which is good.

[Steven G Webb]

I know very little about HDR and have only practiced a handful of times. I think the exposure sequence -1 0 +1 is an overly simplified approach. How does one arrive at the exposure value of 0 anyway? Does the scene have elements that fall outside the dynamic range of the -1 and +1 for the particular sensor? Maybe spot metering for the deepest shadow with detail, then the brightest highlight with shadow would be a good approach. The midtones should surely fall in the acceptable range, if not then an exposure somewhere between the two extremes might be necessary. Two, three, five I don't think there is a number of exposures that is optimal, I do think the fewer exposures the better. If two will work, don't use three. Doing so seems to me only to add more processing and that has to be visible in the end results. For me it's been far easier to overcook an HDR than to produce a natural looking image.

[Duck]

Oh, oh, I think you opened up a big can of proverbial worms. This is a big topic with lots of 'schools' of thought.

In the beginning, long before purpose built HDR software, (or software at all) exposure blending was done in the darkroom by skilled technicians. But that's ancient history now.

Today's HDR programs have gotten better at tone mapping and the range of effects that can be pulled from these programs range from a natural looking image where shadows and highlights each have detail, to the more illustrative style or overprocessed, oversaturated look that has polarized people to the effect. Because of such wide application of the effect of tone mapping it has led to just as wide a range of capturing techniques.

Personally, I prefer the more natural look when it comes to landscapes and architecture and a more exaggerated look for some things like still life, some florals, animals and people (depending on final intent). For capture, though, I pay attention to the amount of light and the actual dynamic range available.

When it comes to capture, if I have the time I will place my exposure to capture the full range. When I'm running and gunning I'll split the difference. Sometimes one up, one down unless it's closer to high noon where I might push it to two up, two down. Nowadays, with the increased range of capture from modern sensors (raw capture) I find I can push the post processing enough to expand the dynamic range without tone mapping.

[Steven G Webb]

The Orton Effect.

[Duck]

The Orton Effect.

That's a totally different effect and process. How does that relate to HDR? I'm not following.

[pop511]

Interesting set of responses. I am yet to use my latest camera Canon 1dxMkii for hdr, but I know the old one Canon 1ds Mkii has an exposure range of 10 1/3 stops extrapolated. I know that if inside a building and bright sun through any window, I cannot get detail from outside with detail inside. I have to make a choice as to proper exposure for the scene I wish to cover, or do hdr. That being said I want to come back to my original argument.
Those of you on this forum that have used hdr, can you try my experiment. Merge all sequences by whatever method you use, then, merge your low and high exposures only.
I am curious as to what results you get and your reports.
Kind regards;

[Steven G Webb]

The Orton Effect.

That's a totally different effect and process. How does that relate to HDR? I'm not following.

Earlier there was mention that HDR in film required sandwiching negatives. Orton's effect was similar. Using one over exposed negative and one under exposed being part of the process. I threw it out there from nostalgia for film manipulation talk.

[St3v3M]

I've been curious too and am having fun listening in! S-