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HDR is normally described as a post processing technique.

I usually can't find time to do post-processing - thus I have turned out to favor SOOC-pictures ;-)

My question is: Is it possible to create HDR-photos by multiple-exposure?

Update:

I'm not asking for a built-in post-processing tool in the camera.

I want to know if multiple-exposure can be used as a capture-technique when the scene has a large difference in exposure. I.e. both overexposed and underexposed parts. (Eg. in a landscape where the sky is very bright and the ground is very dark).

Using "HDR" as a term is probably not correct. The issue I'm trying to solve is simply to fetch the details from all parts of the scene. I was wondering if this could be done by multi exposure... (After som thinking, I guess not...)

As far as I can tell - a GND filter is the only way to go. I.e. to reduce the bright parts of the picture more than the dark parts...

enter image description here
Picture from the article "GND Filters vs. Exposure Blending"

Jørn E. Angeltveit
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    possible duplicate of Which cameras have built-in HDR? – mattdm Jun 09 '13 at 19:10
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    Ah. Thanks. Perhaps this one too: http://photo.stackexchange.com/questions/38689/how-did-film-photographers-deal-with-issues-around-dynamic-range :-/ ? – Jørn E. Angeltveit Jun 09 '13 at 19:12
  • @mattdm, Hm. The other question doesn't really answer my question (I have a D90, btw, and not on the list). As far as I can tell, the other question is about having a built-in HDR post-processing tool. And the answers recommencement taking BKT-exposures and then use an external post-prosessing-software... *I would like to get a similar effect during the actual exposure.* – Jørn E. Angeltveit Jun 09 '13 at 19:19
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    Well, Nikon's active d-lighting is probably the closest you can get. But, basically, if your camera doesn't have the in-camera processing to do a certain thing... it doesn't have the in-camera ability to do that thing. – mattdm Jun 09 '13 at 19:24
  • Perhaps that's my question. "Is HDR only a "processing"-thing, or could the same effect/problem be solved trough the actual exposing (aka film/dias capturing technique)". – Jørn E. Angeltveit Jun 09 '13 at 19:29
  • I think this answer to another question should help with that. It comes down to what exactly you mean by HDR (and that answer explains it well). – mattdm Jun 09 '13 at 19:32
  • Perhaps I should rephrase my question (or ask a new one). I'm just wondering if it is possible to combine 3 "shots" into a single picture by multiple-exposure - and get an overall "perfect" exposure by combining over- and under-exposed shots. ... ... After giving it a second thought, I think I understand that that's not possible. The overexposed shots would "burn out" the "perfect" areas of the previously taken underexposed shot... Right? – Jørn E. Angeltveit Jun 09 '13 at 19:48
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    Unless the camera has a feature to map the different exposures properly — that's what the in-camera HDR feature in the other cameras is. – mattdm Jun 09 '13 at 19:54
  • You would definitely have to be on a very sturdy tripod because there is no auto-align in Multiple Exposure mode. – Itai Jun 09 '13 at 23:04
  • Read your camera's manual... – Mike Jun 12 '13 at 16:07
  • @Mike. This wasn't a question about camera features. I was wondering if I could bring forth the "details" of the underexposed and overexposed parts of a scene with multi-exposure. What would you do with dias film? I still haven't got any answer to that question (and it's definitely not described in my cameras manual). After some thinking, I now believe it's impossible to solve that by multi-exposure. I've learned that GND might be used to "even out" the exposure-range. I probably made a big mistake by bringing in the "HDR" term... – Jørn E. Angeltveit Jun 12 '13 at 21:59
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    @JørnE.Angeltveit No, you can't. The second exposure adds more light on top of the first exposure, so if either of the exposures blow out the highlights, the multiexposure will be even more blown out since it gets the light from the other exposure on top. A graduated ND is not a general replacement, but it works if your picture has one bright and one dark part and a more-or-less straight line separating them. Or you could use gelatin/plastic ND filters and cut them to the shape you need. IMO multiple shots and post processing is easier. – j-g-faustus Jun 12 '13 at 23:09
  • I think what you are describing - "bring forth the "details" of the underexposed and overexposed parts of a scene" - is exactly what HDR does. You don't need to tone map it to make a crazy over saturated cartoony photo, but you would need to combine the multiple exposures. Either your camera can do natural looking HDR's (ref your manual), or you do it later in post. – Mike Jun 13 '13 at 13:10

2 Answers2

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The short answer is: you can, if your camera has a feature to support it (see Which cameras have built-in HDR?) but really can't if it doesn't.

"HDR", which stands for High Dynamic Range, is a little bit of a misnomer, because the end result is a photo with regular dynamic range displayable on a typical monitor or print, but which shows detail from across a wider range from dark to light than a straightforward mapping to that media normally would. Michael Nielsen's answer to another question on HDR covers this nicely.

The important part is that in order to produce this mapped image, the processing software (either in-camera or out) needs to know what to do. Cameras with a built-in feature to do HDR have that knowledge; that's exactly what the feature is. * Other cameras just don't. (But, the software to do it after the fact is easy, inexpensive or free, and gives you a lot more control.)

(Plus, usually also some sort of rudimentary auto-alignment to compensate for slight shifts. This will be much better on a computer.)

Community
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mattdm
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With the D90 you can use the multiple exposure feature, on a tripod, bracket the exposures, with Auto Gain turned on. As you say in your comment, if one exposure is great for the brighter part of your image, the next one will probably blow it out. You'll end up with an average exposure.

If you don't like post-processing, there are quick ways to do a blend of two images in post without HDR software and spending a lot of time. For one, you can stack two images in layers and use the layer "blend-if" sliders to let certain tones in one layer blend in on top of the other layer, rather than using masks or HDR processing. There's a lot more processing power and memory on a computer than on your D90 to do this, so you're bound to get better results than in-camera.

MikeW
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