snubbr.com

HDR (High Dynamic Range) images: what's the point?
From what I can gather, the human ape an see a far greater range of colour and shades than any monitor..

Monitors often "see" more (or different) colours to that of an inkjet printer..

Inkjet printers do better in this regard than 4 colour litho printing..

So when we produce HDR images, what is the point? Is there any print process that can show an HDR image in all it's (wide dynamic range) glory?..

Comments (19)

I think you've misunderstood. The whole point of HDR images is to compress a very wide dynamic range into one that monitors and printers can reproduce, while maintaining local contrast so that the images don't look dull and unsatisfying..

Our eye/brain does a similar thing. The eye isn't inherently able to see a wide dynamic range, but the brain puts a collection of images together in a way that deceives us into thinking that we can see the sky and the ground (for example) at similar brightnesses. In fact, the eye darts between them, the pupil changing size as it does so. The brain remembers both and puts them together...

Comment #1

The point is not what the eye/brain can reproduce, nor what monitors can currently show. DR, HDR, whatever may be has nothing to do with your question at all. It's moreso what the media can reproduce/capture that matters. Good ol'e brain will assimilate anything that's put in front of it but has a prob between what it 'saw' to begin with and what we try to save as on our hard drive. Hence the $$$ we donate to software to reproduce this and the eternal struggle to 'make it all better'. Compensate for the techno shortcomings if you will.Cheers Suby..

Comment #2

Basically saying the same thing but in different words.Leonhttp://homepage.mac.com/leonwittwer/landscapes.htm..

Comment #3

To continue on what has been said-.

The human eye can see 20 or more stops; while the camera/monitor/printer can see/record/print about 6 stops..

When you take a a shot with a dslr and get home and put it on the monitor you say- it didn't look like that. that is because your eye can adjust to the wide range between the super bright and super dark but nothing else can..

The answer is hdr software and technique. what it does is take a scene with 11stops of light and compresses down so that it has the normal 6 the photo dvices can use. when you normally take a high DR pic to keep from blowing highlights the whole thing is darkened down. he result is that it doesn't look real..

Below are 2 shots. the first is the matrixmetered shot taken by a dslr. check the dark area under the trees on the left. also the sky color, wrong blue. there is no way the camera can record the right blue and get the rest right. the sky itself was blindingly bright..

The second pic is a hdr shot. the sky is now the right color while the dark area under the trees, which was really not visable in the regular shot is now showing detail..

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window..

Comment #4

To do hdr-.

If you put camera into full auto matrix metering, take first shot note fstop and shutter speed. put camera into full manual, see if camera still has the matrix fstop and shutter speed. if yes, then using shutter speed go up 2-4 shutter speeds 1 fstop worth of shutter speed at a time. the back to matrix shutter speed and go down same number of shutter speeds.this is on a tripod with cable release..

No, you should not use 1 raw shot and convert 1 stop up and down, because their is not enough dynamic range in the 1 raw shot. dynamic range is why we are doing this, hdr is trying to get all it can..

The group of shots can be raw or jpeg. if jpeg they can be used as is. if raw remember that you HAVE to batch process all 5-9 shots. this is because the pp has to be all the same on every pic. you cannot, for example make any attempt to get the shadow details of the group of raw pics, because that would require different amounts of pp, and you cannot do that with hdr. the pp for all shots has to be identical..

For me I just shoot them in jpeg and use them from the camera, that way they are all identical because the camera jpeg settings are the same for every shot. I also put my hand streched in front of the lens and take a check shot and when done take a ending shot with hand. this tells me where the hdr group is on my memory card when I transfer to the pc..

The only important item is to bracket using shutter speeds only. if fstops are used it changes dof between shots. and shoot enough shots, 5-9 is the optimum. the only other thought is to shoot a scene that deserves the the hdr technique, too many people are shooting hdr because it is new or different or whatever. many people are using hdr software on scenes that do not have enough dynamic range; they end up with images that have been enhanced by hdr software, they are not hdr images. the dynamic range was not in the scene to begin with.

This can be checked with a spotmeter on different areas. NOTE: use of auto bracketing on a camera may not work unless you know the bracketing is using the shutter speeds to bracket. in any event, you really need 5-9 shots for hdr; this is more than the auto bracket fcn on almost all cameras. and the bracketing has to be both sides of the middle shot. make you use enough brackets to cover the previously checked dynamic range.

And the scene should have no movement, if so the item will blur in the hdr image..

Do not adjust the focus. set the focus on infinity or use a hyperfocalsetup for focus..

Do not adjust the white balance for individual shots. go with awb or 1 setting and do not change it..

Remember, hdr was created and meant for scene that have a dynamic range that exceeds the dynamic range of the camera sensor, about 5-6stops. hdr with the required software allows the user to capture a scene that has very high dynamic range...

Comment #5

The second shot is not an HDR image of the first. You've blown sky, cloud, and water detail. If it was HDR, it was a poorly implemented HDR scheme. The second image looks more like you simply increased the exposure by about 1-1.5EV and did nothing to maintain the sky. The first image is also underexposed throughout by about 0.5 stops. Perhaps you only used a -0.5EV and +1.5EV image and blended rather than HDR?.

Please correct me if I'm wrong..

Tim'Be the change you wish to see in the world.' -Mahatma Gandhihttp://www.flickr.com/photos/timskis6/..

Comment #6

Timskis6 wrote:.

The second shot is not an HDR image of the first. You've blown sky,cloud, and water detail. If it was HDR, it was a poorly implementedHDR scheme. The second image looks more like you simply increasedthe exposure by about 1-1.5EV and did nothing to maintain the sky.The first image is also underexposed throughout by about 0.5 stops.Perhaps you only used a -0.5EV and +1.5EV image and blended ratherthan HDR?.

Please correct me if I'm wrong..

Agree, bad example. I like to play with HDR and it's a DIFFICULT thing to do. Ok, it's easy to do technically, but it's much harder to make it aestethically pleasing and meaningfull..

Here, three examples of mine, one good, one bad, one in the middle..

The good one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

The not so good one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

The bad one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

As you can see, it's totally easy to overdo it..

/d/n..

Comment #7

GaryDeM wrote:.

To continue on what has been said-the human eye can see 20 or more stops;.

Yes - but *not* all at the same time. To see the brightest highlights our pupils contract, just like the diaphragm of a camera lens. To see into deep shadows the pupils dilate to let in as much light as possible, and in darkness we stare at things to pick up more visual information - somewhat like a 'long exposure'. But the eye can't do both these things *at the same time*, and that is the key point..

The camera can also see 20 stops, but it can't see them all at the same time. HDR is a way of combining shots taken in different parts of that 20-stop range to produce one image..

Another point that ought to be mentioned is that many of the "HDR" images people post here have the HDR effect greatly exaggerated for artistic effect. Sometimes it looks great, sometimes not..

It's interesting to compare HDR images with classical landscape paintings. I don't think artists consciously set out to "compress the dynamic range while maintaining local contrast" but that is what they often do...

Comment #8

It all depends on what you like. to me, NONE of the three are any good. why? because real world colors do not look like that. it is that simple..

Many people are using hdr software to emphasize color in some way in their hdr photos but the the real scenes are really never like that. they are pastels not bright sharp colors...

Comment #9

Timskis6 wrote:.

The second shot is not an HDR image of the first. You've blown sky,cloud, and water detail. If it was HDR, it was a poorly implementedHDR scheme. The second image looks more like you simply increasedthe exposure by about 1-1.5EV and did nothing to maintain the sky.The first image is also underexposed throughout by about 0.5 stops.Perhaps you only used a -0.5EV and +1.5EV image and blended ratherthan HDR?.

Please correct me if I'm wrong..

Tim'Be the change you wish to see in the world.' -Mahatma Gandhihttp://www.flickr.com/photos/timskis6/.

The first shot is the middle one of the 9 shot hdr group. it was done using matrix metering. it represents THE REASON that people do hdr. the first shot is not underexposed; if the exposure was any higher the sky would blow on highlights. just checked the image in pe6's histogram, the highlights are not blow at all neither is anything else. what is obvious is the group on the left side of the histogram where the area under the trees on the left side are buried in shadow.

To keep the highlight unblown the shadows are are going to be dark..

The second shot is a hdr image. it was made up of 9 shots then turned into a 32bit image. in converting to 16bit I did not use tonemapping; for the reson that I do not like it. tonemapping emphasizes color it gives a warped image of the scene and real world. the real scenes simply do not look like tone mapping with jazzed up colors. I have found that if I use highlight compression in cs2 to convert to 16bit tiff the colors are not emphasized and generally look weird to me.



Try this article of m reichman on hdr. note the paste muted real appearing color in the intial shot at the top of article. when he made it the colors are not emphasized and super strong.http://www.luminous-landscape.com/tutorials/hdr.shtml.

With all the people doing it usually in phtotmatrix the hdr images are coming out looking like cartoons with the strong jazzed up colors. to fully understand what I am saying consider this: I do not think that those images are in any wrong or bad but they do not represent accurately the real scene they came from. if people likethem, fine. but I do not they are not real looking; and real looking images are what I trying to acheive. my hdr shot looks very close to the way I saw it that day taking the pics, and in doing so I am satisfied. if it does not have enough super colors for you, then we are talking about photographic likes and dislikes, which an entirely different thing...

Comment #10

GaryDeM wrote:.

It all depends on what you like..

Indeed..

To me, NONE of the three are anygood..

I like the first quite a lot..

Why? because real world colors do not look like that. it isthat simple..

I didn't say it was documentary photography..

Many people are using hdr software to emphasize color in some way intheir hdr photos but the the real scenes are really never like that..

Hmmm... So, you mean there is a way to perfectly reproduce a scene as it was? Let's agree to disagree - at least until they come up with holographic cinematography with taste, feel and smell as well. And even then we'll probably argue on Sony vs Nikon reproduction of wild mint flavour .

Is Velvia accurate? Is Ilford FP4 truer than TriX?.

HDR is just another tool which can be used right or wrong (and I am very often guitly of doing it wrong!!!), as all the others. Might be a pretty good choice if you want some drama in your image..

They are pastels not bright sharp colors..

If it's fog, yes. In good light, you get all the bright sharp, contrasty colors you want..

And, to poke you a little, I don't remember seeing green clouds very often, as well. .

/d/n..

Comment #11

Devnull wrote:.

GaryDeM wrote:.

It all depends on what you like..

Indeed..

To me, NONE of the three are anygood..

I like the first quite a lot..

Why? because real world colors do not look like that. it isthat simple..

I didn't say it was documentary photography..

Many people are using hdr software to emphasize color in some way intheir hdr photos but the the real scenes are really never like that..

Hmmm... So, you mean there is a way to perfectly reproduce a scene asit was? Let's agree to disagree - at least until they come up withholographic cinematography with taste, feel and smell as well. Andeven then we'll probably argue on Sony vs Nikon reproduction of wildmint flavour .

Is Velvia accurate? Is Ilford FP4 truer than TriX?.

HDR is just another tool which can be used right or wrong (and I amvery often guitly of doing it wrong!!!), as all the others. Might bea pretty good choice if you want some drama in your image..

They are pastels not bright sharp colors..

If it's fog, yes. In good light, you get all the bright sharp,contrasty colors you want..

And, to poke you a little, I don't remember seeing green clouds veryoften, as well. .

/d/n.

I didnot say it was documentary photography. I DID. I want my pics to look as close to the real scene as possible. and that means emphsized colors are a nono..

Real scenes are pastels. walk out your door where even in bright sunlight is there a color with the intensity of the photomatrix colors in hdr? there are not any..

You can poke ll you want. just looked at my 2 shot in the above reply. clouds are while or a shade thereof the sky is blue in either shot on my clibrated monitor.what green are you talking about?..

Comment #12

I didnot say it was documentary photography. I DID. I want my picsto look as close to the real scene as possible. and that meansemphsized colors are a nono..

To each his own. Pure curiosity, do you use polarization filters?.

Real scenes are pastels. walk out your door where even in brightsunlight is there a color with the intensity of the photomatrixcolors in hdr? there are not any..

Disagree. First, good light is not bright sunlight. Early morning and late evening yield the lateral light which emphasises both colors and shadows. And if you take the time to look at the nature, you'll see brilliant and strong colors, from the green of the foliage to the colors on bugs and snakes..

You can poke ll you want. just looked at my 2 shot in the abovereply. clouds are while or a shade thereof the sky is blue in eithershot on my clibrated monitor.what green are you talking about?.

You have lowered the contrast too much; the highlights in the top clouds are not natural. I would guess that in the left the blue channel is burned, therefore the strange hue, while in the right some red popped out of the blue (pardon the pun). The perceptual effect is green in the left and mangenta in the right, due to the surrounding blue...

Comment #13

GaryDeM wrote:.

To continue on what has been said-the human eye can see 20 or more stops; while thecamera/monitor/printer can see/record/print about 6 stops.when you take a a shot with a dslr and get home and put it on themonitor you say- it didn't look like that. that is because your eyecan adjust to the wide range between the super bright and super darkbut nothing else can..

The answer is hdr software and technique. what it does is take ascene with 11stops of light and compresses down so that it has thenormal 6 the photo dvices can use. when you normally take a high DRpic to keep from blowing highlights the whole thing is darkened down.he result is that it doesn't look real..

Below are 2 shots. the first is the matrixmetered shot taken by adslr. check the dark area under the trees on the left. also the skycolor, wrong blue. there is no way the camera can record the rightblue and get the rest right. the sky itself was blindingly bright.the second pic is a hdr shot.



[ pics snipped ].

Thanks for that informative example and explanation...

Comment #14

GaryDeM wrote:.

To do hdr-if you put camera into full auto matrix metering, take first shotnote fstop and shutter speed. put camera into full manual, see ifcamera still has the matrix fstop and shutter speed. if yes, thenusing shutter speed go up 2-4 shutter speeds 1 fstop worth of shutterspeed at a time. the back to matrix shutter speed and go down samenumber of shutter speeds.this is on a tripod with cable release.no, you should not use 1 raw shot and convert 1 stop up and down,because their is not enough dynamic range in the 1 raw shot. dynamicrange is why we are doing this, hdr is trying to get all it can.the group of shots can be raw or jpeg. if jpeg they can be used asis.

Youcannot, for example make any attempt to get the shadow details of thegroup of raw pics, because that would require different amounts ofpp, and you cannot do that with hdr. the pp for all shots has to beidentical.for me I just shoot them in jpeg and use them from the camera, thatway they are all identical because the camera jpeg settings are thesame for every shot. I also put my hand streched in front of the lensand take a check shot and when done take a ending shot with hand.this tells me where the hdr group is on my memory card when itransfer to the pc.the only important item is to bracket using shutter speeds only. iffstops are used it changes dof between shots. and shoot enough shots,5-9 is the optimum.

Many people are using hdrsoftware on scenes that do not have enough dynamic range; they end upwith images that have been enhanced by hdr software, they are not hdrimages. the dynamic range was not in the scene to begin with. thescene for hdr should have a very wide dynamic range. this can bechecked with a spotmeter on different areas. NOTE: use of autobracketing on a camera may not work unless you know the bracketing isusing the shutter speeds to bracket.

And the bracketing has to be both sides of the middleshot. make you use enough brackets to cover the previously checkeddynamic range. it does little good to bracket for a 10stop dynamicrange when the scene has 14stops.and the scene should have no movement, if so the item will blur inthe hdr image.do not adjust the focus. set the focus on infinity or use ahyperfocalsetup for focus.do not adjust the white balance for individual shots. go with awb or1 setting and do not change it.remember, hdr was created and meant for scene that have a dynamicrange that exceeds the dynamic range of the camera sensor, about5-6stops.

Wow!.

Thanks for that brilliant reply..

That was a very helpful lesson in HDR (I have been on a website of an HDR software publisher and there was tons of words and I was still lost; yet you have made me understand in a few short parargraphs)..

Thanks...

Comment #15

Devnull wrote:.

Timskis6 wrote:.

The second shot is not an HDR image of the first. You've blown sky,cloud, and water detail. If it was HDR, it was a poorly implementedHDR scheme. The second image looks more like you simply increasedthe exposure by about 1-1.5EV and did nothing to maintain the sky.The first image is also underexposed throughout by about 0.5 stops.Perhaps you only used a -0.5EV and +1.5EV image and blended ratherthan HDR?.

Please correct me if I'm wrong..

Agree, bad example. I like to play with HDR and it's a DIFFICULTthing to do. Ok, it's easy to do technically, but it's much harder tomake it aestethically pleasing and meaningfull..

Here, three examples of mine, one good, one bad, one in the middle..

The good one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

The not so good one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

The bad one:.

Image control:Zoom outZoom 100%Zoom inExpand AllOpen in new window.

As you can see, it's totally easy to overdo it..

/d/n.

I know I am being a bit dim here (being an HDR newbie) but can you please explain why/how those three pics represent The Good, The Not So Good, and The Bad respectively..

Thanks in advance...

Comment #16

Plevyadophy wrote:.

I know I am being a bit dim here (being an HDR newbie) but can youplease explain why/how those three pics represent The Good, The NotSo Good, and The Bad respectively..

Aesthetics .

Thanks in advance...

Comment #17

Devnull wrote:.

Plevyadophy wrote:.

I know I am being a bit dim here (being an HDR newbie) but can youplease explain why/how those three pics represent The Good, The NotSo Good, and The Bad respectively..

Aesthetics .

Thanks in advance..

Well, in that case, I agree with you. I just thought that maybe there was some more technical reason..

Thanks for your contribution to this thread, I have learnt a lot...

Comment #18

Devnull wrote:.

You can poke ll you want. just looked at my 2 shot in the abovereply. clouds are while or a shade thereof the sky is blue in eithershot on my clibrated monitor.what green are you talking about?.

You have lowered the contrast too much; the highlights in the topclouds are not natural. I would guess that in the left the bluechannel is burned, therefore the strange hue, while in the right somered popped out of the blue (pardon the pun). The perceptual effect isgreen in the left and mangenta in the right, due to the surroundingblue..

You're both wrong, you know. Gary, please take another look, there is colour in those clouds; Devnull the reason is not what you say. The clouds have moved in between shots, and the HDR software isn't clever enough to sort that out. It tries to account for the changes from blue to to white and from white to blue as changes due to the exposure variation (with areas that the bright cloud moves *into* as the exposure *reduces* being especially hard for the software to understand), and consequently it creates those odd colour artefacts..

I honestly don't think this was a very good subject for the HDR treatment. The first shot is pretty good, maybe very slightly underexposed but easily recoverable, especially from RAW. The deep shadows under the trees simply look natural, but if you absolutely must recover detail in those areas (but ask yourself why?) then it should have been done locally without changing the whole image...

Comment #19

Click Here to View All...

Sponsored Amazon Deals:

1. Get big savings on Amazon warehouse deals.
2. Save up to 70% on Amazon Products.


This question was taken from a support group/message board and re-posted here so others can learn from it.

 

Categories: Home | Diet & Weight Management | Vitamins & Supplements | Herbs & Cleansing |

Sexual Health | Medifast Support | Nutrisystem Support | Medifast Questions |

Web Hosting | Web Hosts | Website Hosting | Hosting |

Web Hosting | GoDaddy | Digital Cameras | Best WebHosts |

Web Hosting FAQ | Web Hosts FAQ | Hosting FAQ | Hosting Group |

Hosting Questions | Camera Tips | Best Cameras To Buy | Best Cameras This Year |

Camera Q-A | Digital Cameras Q-A | Camera Forum | Nov 2010 - Cameras |

Oct 2010 - Cameras | Oct 2010 - DSLRs | Oct 2010 - Camera Tips | Sep 2010 - Cameras |

Sep 2010 - DSLRS | Sep 2010 - Camera Tips | Aug 2010 - Cameras | Aug 2010 - DSLR Tips |

Aug 2010 - Camera Tips | July 2010 - Cameras | July 2010 - Nikon Cameras | July 2010 - Canon Cameras |

July 2010 - Pentax Cameras | Medifast Recipes | Medifast Recipes Tips | Medifast Recipes Strategies |

Medifast Recipes Experiences | Medifast Recipes Group | Medifast Recipes Forum | Medifast Support Strategies |

Medifast Support Experiences |

 

(C) Copyright 2010 All rights reserved.