Is this HDR?

[WhoDo]

I'd like to know what APers think of this image ... is it HDR? I'll post a BEFORE shot later and then tell you how it was achieved. The question remains, though, is it HDR? What exactly IS HDR anyway?

swansea_N6340.jpg

[xxdrakexx]

I'm going to say no it's not HDR lol

[ameerat42]

Waz.
No. (NIMO, anyway).
HDR - an image that illustrates (ie, shows detail across) a high dynamic range.

That's AFAIK.

This image shows a good tonal range, from the deep shadows (with no detail in them but that's not the point) to the light lattice.
Also, the colour seems to be preserved in all but the darkest tones.

(Mainly opinions, a few impressions, a bit of arm-waving, and Presto!)
Am.

[teylward]

As above. HDR ( High Dynamic Range) is usually achieved through merging multiple images of the exact same photo, but each with a different exposure level. To do this, it is best to use the AEB (Auto Exposure Bracketing) function on your camera. Then set exposure difference at +1/-1EV or what ever tickles your fancy.
I use Photomatix program on the computer for merging the images.

Good luck.

[ScottM]

I'd say that it's not. There are no areas close to being blown out, and almost no area close to fully underexposed (left side of the chair just loses a little). HDR - in snapping or PP rather than a technical definition - is usually when the range of light in the scene is greater than what the camera sensor can record.
Having said that, you might have done a little PP-ing on it judging by the colour, darkness, and sharpness of the grass

[WhoDo]

Ok, so the general consensus is "No", which begs the question "Why not"? Here is the original image for comparison, and a link to a blog post on the subject from Matt Kosklowski of Lightroom guru fame.

swansea_N6340-2.jpg

Let the "discussion" begin. Personally, I'd always believed that you couldn't capture a broad enough dynamic range in a single shot to produce what is termed High Dynamic Range images, BUT if you think about shooting in RAW, the full gamut is already there in your image data and your exposure settings are only as good as the sensor limits anyway. I mean, you aren't actually altering your sensor's capability when you choose a different exposure level for each shot, are you? You may be doing that by altering your ISO setting, but your Ev level? Or am I showing my ignorance of the technicalities here?

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HDR - in snapping or PP rather than a technical definition - is usually when the range of light in the scene is greater than what the camera sensor can record.

Ooh, don't know if I'd agree with that one, Scott. If the sensor can't record it then the settings you apply in terms of + or - Ev aren't going to help all that much, are they? I guess it comes down to just what the Ev shift changes in terms of the sensor's ability to record data in RAW format.

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HDR ( High Dynamic Range) is usually achieved through merging multiple images of the exact same photo, but each with a different exposure level

And yet we talk in terms of different sensors having a greater or lessor dynamic range than each other, don't we Travis? I'm sure I'd prefer the dynamic range of the sensor in the Nikon D800/E to that in the quite capable Nikon D70 of earlier days. What passed for HDR on the D70, and required a bracket of 3 shots to achieve, may well be possible in a single shot from the D800/E, mightn't it? Just thinking out loud is all, and trying to challenge you guys likewise.

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HDR - an image that illustrates (ie, shows detail across) a high dynamic range....[snip]...
(Mainly opinions, a few impressions, a bit of arm-waving, and Presto!)

Was there an abracadabra in there, too, am? I guess the question becomes what is normal range in order that we can contrast the "high" in High Dynamic Range. I agree that we are probably talking about the breadth of detail from near black (no detail data) to near white (detail data obscured or beyond human or camera perception). Who is to say that is only possible in multiple data captures? Are we not just exploring the limits of the sensor rather than increasing its capability each time we use an Ev adjustment?

[ricktas]

HDR, or high dynamic range is a technique to capture more detail than your sensor can in a single shot. Basically the dynamic range of your sensor is the largest possible signal a pixel site can capture (without being pure white) or the lowest possible signal a pixel site can capture (without being pure black) with a single shot. Thus the limiting factor is the dynamic range of your sensor, within a given single photo.

High dynamic range is the name given to processing technique that results on a dynamic range larger than that which your sensor can capture in a single shot. The basic premise is that you shoot under-exposed for one shot, good exposure for a second one, and over-exposed for a third, then you combine those to create a photo that includes the furthest points of dynamic range from all three original photos, such that the resultant photo has more dynamic range than your sensor is capable of capturing in a single photo.

Now you can process one single capture into 3 exposures by using your PP software to under-expose and save, over-expose and save, and use those three photos to create an HDR, but often this is referred to as Psuedo-HDR.

some facts. The Nikon D800 has a dynamic range of 14.4 stops. Printed photos are about 6.5 stops and the human eye is somewhere between 20 and 25 stops.

By using three separate photos, you are using the entire available dynamic range of your sensor, to capture each photo.

Say your camera sensor has a dynamic range of 12 stops. But the scene you are taking a photo of has a dynamic range of 20 stops. You cannot capture all of that at once. So you capture 20-8 in your first, 16-4 in your second and 12 to 0 in your third, and using HDR processing create a photo that covers the whole twenty stop range. If you use one photo taken at say 16-4 and process that to create a psuedo-HDR, you are really only creating a photo with 12 stops, cause that is all you had to start with.

[mikew09]

No I looked at this image and then went straight to the reply so I did not have any read of what is already posted. I would say no to HDR due to the dark areas and lack of detail on the dark areas on the veranda. Now rightly or wrongly, for me HDR is about gathering detail across the full range of exposures. I would consider the shot hdr if the dark areas where lighter shadows and revealed some detail. It certainly has some feel of HDR but for me looks more like some work on colours tones, saturation etc.

I have an opinion on HDR, HDR is great to capture the dynamic range and reveal detail in dark areas that would not be normally exposed correctly. Example may be an old blacksmiths shop with lots of interest and a nice sunset behind with maybe a horse standing int the light. To make the shot what it is requires maybe 3 or more stops of exposure - hence the use of HDR, but I strongly believe the shot should also border on the a that point of natural.

Remove my waffle and my answer is NO - not hdr :-)

[WhoDo]

Say your camera sensor has a dynamic range of 12 stops. But the scene you are taking a photo of has a dynamic range of 20 stops. You cannot capture all of that at once. So you capture 20-8 in your first, 16-4 in your second and 12 to 0 in your third, and using HDR processing create a photo that covers the whole twenty stop range. If you use one photo taken at say 16-4 and process that to create a psuedo-HDR, you are really only creating a photo with 12 stops, cause that is all you had to start with.

Ah, now that explains what I was missing; Ev does change what the sensor is capable of registering in RAW data. So, strictly speaking, if I use that 12-stop range in my current camera to produce a full 12-stop image, would that be considered a HDR image when compared to one taken on a sensor that only had, say, an 8 or 10 stop dynamic range? In other words, has the point of HDR been superceded by modern high dynamic range sensors, or will the goal posts keep moving till we can no longer tell the difference with the human eye?

[welly]

Ok, so the general consensus is "No", which begs the question "Why not"? Here is the original image for comparison, and a link to a blog post on the subject from Matt Kosklowski of Lightroom guru fame.

swansea_N6340-2.jpg

Let the "discussion" begin. Personally, I'd always believed that you couldn't capture a broad enough dynamic range in a single shot to produce what is termed High Dynamic Range images, BUT if you think about shooting in RAW, the full gamut is already there in your image data and your exposure settings are only as good as the sensor limits anyway. I mean, you aren't actually altering your sensor's capability when you choose a different exposure level for each shot, are you? You may be doing that by altering your ISO setting, but your Ev level? Or am I showing my ignorance of the technicalities here?

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Ooh, don't know if I'd agree with that one, Scott. If the sensor can't record it then the settings you apply in terms of + or - Ev aren't going to help all that much, are they? I guess it comes down to just what the Ev shift changes in terms of the sensor's ability to record data in RAW format.

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And yet we talk in terms of different sensors having a greater or lessor dynamic range than each other, don't we Travis? I'm sure I'd prefer the dynamic range of the sensor in the Nikon D800/E to that in the quite capable Nikon D70 of earlier days. What passed for HDR on the D70, and required a bracket of 3 shots to achieve, may well be possible in a single shot from the D800/E, mightn't it? Just thinking out loud is all, and trying to challenge you guys likewise.

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Was there an abracadabra in there, too, am? I guess the question becomes what is normal range in order that we can contrast the "high" in High Dynamic Range. I agree that we are probably talking about the breadth of detail from near black (no detail data) to near white (detail data obscured or beyond human or camera perception). Who is to say that is only possible in multiple data captures? Are we not just exploring the limits of the sensor rather than increasing its capability each time we use an Ev adjustment?

A digital camera sensor has a dynamic range of about 11 stops. If you're shooting a scene which has a wider dynamic range than this, you simply can't capture it on your camera's sensor. I'm not really sure what your argument or point is? That we can call images that look to have a high dynamic range, even if they've not used the traditional HDR tools to process them, HDR images?

If you want, I guess. I'm not sure what that achieves though. HDR in photography terms is just a post-processing method. Why not just call them photographs?

[WhoDo]

I'm not really sure what your argument or point is? That we can call images that look to have a high dynamic range, even if they've not used the traditional HDR tools to process them, HDR images?

If you want, I guess. I'm not sure what that achieves though. HDR in photography terms is just a post-processing method. Why not just call them photographs?

I was only wondering what HDR is in purely technical terms, Welly. Ricks answer about the ranges of sensors, eyes and printers was helpful to that end. HDR processing came about as a means to overcome the limitations of the sensor, so when and if sensors reach 20-25 stops of dynamic range then there will be no need for bracketed shots and HDR processing. The discussion that sparked this was the one referenced in the original post where I understand Matt Kosklowski is saying that HDR is already redundant as a tool because sensors are so good these days. The answer provided me in this thread is "not yet, they're not".

The "pseudo" HDR effect produced in the image above was made with one of Matt's Lightroom presets (Free if you are interested and follow the link above) but what it really does is give only the appearance of HDR within the given number of stops the sensor is capable of capturing in one image. I just wanted to get my head around all of that, and spark a tiny bit of thought on the subject, that's all.

[zollo]

no a 12 stop sensor is not creating a HDR compared to an 8 stop sensor. it is capturing a higher dynamic range of 12 stops of light from the scene, which is more than 8 stops of light.
basically, a HDR image is one where you are displaying a higher range of light than you can capture with the sensor you are using at the time - in a single shot - whether that is an 8 stop or 12 stop sensor
according to cambridge in colour website, a hdr image can contain more dynamic range than even the human eye can see - hence the unnatural look that hdr images which have been pushed too far exhibit

[ricktas]

Also worth noting. Most monitors cannot display a huge dynamic range (marked as luminance). But Dolby are about to release a 47 inch monitor later this year that has a luminance of 1:1,000,000 (about 20 stops), but sell the BMW to pay for it.

[Ezookiel]

.......so when and if sensors reach 20-25 stops of dynamic range then there will be no need for bracketed shots and HDR processing. ....

No, there will still be a need for HDR. Because when you as a human stand at a scene with bright areas and dark areas, such as a brightly lit cliff face with dark caverns and shadowed areas in it, as you look around the scene and you focus on the shady area, the eye pretty much dedicates it's entire 20-25 stops to JUST that dark area, it's how you can peer into the shadows and see what's there, but then as you look at the brightly lit area, the entire dynamic range of the eye is pretty much being used for the bright areas, so even with a camera that has 20-25 stops of dynamic range, you could still use all that range on the dark areas by over exposing, and all that range on the bright areas by underexposing, and all that range on the scene as a whole to expose it correctly, and then merge those in HDR and STILL have a photo that has a higher dynamic range than the camera alone is capable of, and so still technically an HDR photo.

[ameerat42]

The foregoing discourse contains insights that most of us can appreciate, and appeals to themes that we could generally concur with.
The underlying polemic can hopefully serve to hone the ideas central to the discussion - such as it is - but can inadvertently fog them when they are pursued with too much vigour.

So, there are a number of replies from APers on his first Q, and after several interim responses by WhoDo, are we any closer to an opinion from him? There is an interim second question - not "begged" by the way.

After a while, the responses could tend to answering just the rhetorical, "So what?" Are we talking about the same thing?

Prolonged discussion, without much further direction, could even render this to, "Sow wheat!"

...and then perhaps to a second agrarian revolution?

A(bracadabra and a rabbit from a hat)m.

[WhoDo]

So, there are a number of replies from APers on his first Q, and after several interim responses by WhoDo, are we any closer to an opinion from him?

So as not to beat around the proverbial bush in hopes of flushing some "game" APers, I'll say that the processing done on the single original image does NOT qualify as HDR because it does NOT exceed the 12-stop limitation of the sensor in the final image. To be true HDR the dynamic range of the produced image has to be exceed that capable of being produced from a single recording of the processor.

There is an interim second question - not "begged" by the way.

After a while, the responses could tend to answering just the rhetorical, "So what?" Are we talking about the same thing?

Prolonged discussion, without much further direction, could even render this to, "Sow wheat!"

...and then perhaps to a second agrarian revolution?

A(bracadabra and a rabbit from a hat)m.

The tendrils of thought that meander through your visible cogitations, Am, are truly a marvel to behold. I think I disagree with Ezookiel's postulation on the posited second question as to whether HDR processing will become redundant when sensors reach the range of the human eye viz. 20-25 stops of light. I think it will. After all, what's the point of capturing more than you can effectively discern, much less display or print? For all I know there may be 1000 stops of light data available in the full visible and invisible spectrum, but if I can't see it anyway then, as you pointed out, so what? At that time I think I'd prefer to sow wheat!

[ScottM]

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Ooh, don't know if I'd agree with that one, Scott. If the sensor can't record it then the settings you apply in terms of + or - Ev aren't going to help all that much, are they? I guess it comes down to just what the Ev shift changes in terms of the sensor's ability to record data in RAW format.

And that's exactly my point: + or - Ev won't help if the range is already greater than what the sensor can record. +/- won't 'scale' what the sensor sees, they only shift your exposure towards the upper or lower (in effect).

So we have multiple definitions of HDR now (as expected):

• HDR processing
• a scene with a high dynamic range (as our eyes 'see', and also as we 'interpret')
• recording of a scene via the sensor with a DR greater than what it can record

I don't think we'll get an answer for 'what is normal range', although Rick raises good points about the D800 DR, printed photos, monitors, and the human eye.

Build it and they will come! Even with camera sensors having improved DR some will always want to push the boundaries and get a greater range. HDR processing might change: for processing (such as with layers) some photographers will probably still work on multiple versions of a shot, maybe that have used different exposures, maybe not. Having a higher DR in the raw file gives more options SOOC.

Since all sensors record differently, what's HDR to one person, might not be to another. And similar from one camera to another.

Good discussion

[Steve Axford]

There is obviously a little confusion about HDR. It is not a "look" of a photo even though many assume it to be. As has been said it is just the use of multiple images to merge more than 8 bits of data into an 8 bit image. Of course, most images do this by way of the gamma correction, but HDR carries it a little further by combining multiple images (of different exposures) into a single 24 bit image with no gamma correction. Many people take HDR to mean "no gamnma correction", but this isn't true. You can easily take a normal image and remove the gamma correction and it will look like a photo direct from an HDR program, but it isn't HDR. Well produced HDR often looks exactly like a normal photo, so I guess many people would say it isn't HDR, but it is.

A slight addition to what Rick said. The human brain can see 20 or more bits (stops) of brightness information, but this is only done by scanning and the use of short term memory. The eye can only detect a range of 3 to 4 stops between pixels (a indivisible group of rods or cones), but we have a very clever brain that pieces things together over time and creates a frame about 15 times per second (the rate varies from the centre to the edge of frame). You could say it was HDR because it is the merging of many images to produce a single visual field - which, incidentally, is adjusted by our brain for time and motion, so it's just an approximation of what is there. What is really there is far too much for any brain to process in real time, so we just focus on what has proved useful for us over evolution. This is why camouflage works so well for many animals in nature - they take advantage of the short cuts most animal's vision takes.
Back to photography. Our Brain sees an image which includes a gamma correction, so when we see an HDR image without one, it looks wrong. That's because it is wrong, but some people have taken to them and see those images as being artistic. Personally, I don't agree, but each to their own. Anyway, that sort of HDR is just an effect, like any photoshop filter, but it's not what HDR means.

[swifty]

I've always thought of HDR as a processing technique only (not a 'look' as Steve has said), used to overcome the shortcomings of sensors by combining more than 1 bracketed exposure of the same (or very similar) scene to extend the recorded DR.
Other techniques to allow the capture of more DR than capable by the sensor (whatever that sensor might be) eg. Use of GND filters I would not consider HDR, but just another technique at extending DR capture.
So for a given scene where eg. a D70 may require HDR techniques but a D800 may not, it doesn't make the single D800 shot a HDR image because it's still a single image.
It is true that sensor improvements have lessen the need for HDR techniques but there will always be practical limits to what a single shot can achieve.
Even if a given sensor can record a certain amount of DR in one shot, the noise floor may render the darkest few stops of the image inferior to a HDR image where the darkest portion of the same image has been given a greater amount of exposure to light. Ie. there's greater SNR in the HDR blend compared to the single shot by virtue of greater exposure to light in the HDR bracketed separate exposures to capture the different EV range. Of course this may not matter much depending on the scene and whether there's much detail worth displaying in the shadows.
But greater DR from a single exposure will always be an advantage due to the limitations of obtaining close to identical scenes from 2 separate exposures because of camera/scene motion. And a higher DR sensor can still be used with HDR processing, perhaps with less bracketed exposures than otherwise required from a lower DR sensor.