Talk:High-dynamic-range imaging

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Precision vs. Dynamic Range[edit]

The editing section confuses precision with dynamic range as if they were the same concept and is incorrect. One can have a high precision image (16 or 32 bit) shot from a low dynamic range camera. Also one can have an 8-bit high dynamic range image. The number of stops recorded in an image is separate from how precisely the brightness levels are represented. Precision and dynamic range are related in practice though, as is even stated elsewhere in the article, in that higher precision is more important in HDR images than SDR in that it allows sufficient gradations to be stored for each stop to avoid banding artifacts. — Preceding unsigned comment added by 69.65.51.73 (talk) 08:20, 27 February 2012 (UTC)

Digital only?[edit]

Under the header "Photography", the article reads "[..] images must necessarily be digitized for processing." But! this very article mentions an early creator of analogue HDR, and I am sure there are many more. I think this only contributes to the common misconception of high dynamic range photography being all about the over-saturated colors. Polymeris (talk)

And the awful over-saturated example photograph of the German river scene does nothing to dispel that perception. 83.104.249.240 (talk) 18:34, 11 October 2012 (UTC)
Yes, back in the day when photography required mastering recalcitrant materials and chemical processes, we would sometimes take multiple photos of the same scene and mask and combine them to synthesize an expanded dynamic range image. The idea of this now being blessed with it's own catchy acronym and pseudo-scientific sounding name is so post-modern, don't-cha think? — Preceding unsigned comment added by 131.215.115.31 (talk) 02:11, 7 November 2013 (UTC)

Added more example exposures[edit]

I've added some example exposures of the HDRI. I can't get the positioning looking nice though. If someone else wants to have a go then be my guest. —Preceding unsigned comment added by Deanpemberton (talkcontribs)

I think it wasn't you who added the picture at the beginning of the Article, but IMO, that should be removed. The colors are vomitive, and it isn't a representative example of what HDR is. While I don't like it very much either, the NY shot further down the page is much better in this regard. At the very least, I think, they should be swapped. ~ Polymeris (talk)

Scanning film[edit]

I tracked down where the unreferenced scanning film section was added: [1]. Ren Kusack made the addition. I left a request on his talk page for references. —Darxus (talk) 08:46, 2 January 2011 (UTC)

H-D-R imaging?[edit]

I cannot see why the article title was changed to hyphenate HDR, i.e. from “High dynamic range imaging” to “High-dynamic-range imaging”. This is not how HDR imaging is commonly written, see for example Reinhard et al.’s HDR book. Tony1 just said this was a “MoS requirement”, but I could not find anything about this in WP:TITLE. I would like to see the old (and correct) title restored. Any other opinions? — Richie 13:23, 19 February 2011 (UTC)

WP's Manual of Style has sections on the use of professional-standard typography, including hyphens and dashes. Obviously, an article title should not be different from the article text in this respect. Omitting hyphens might be the practice of some specialists (as in many scientific/technical fields), but here we write for a readership with a wide range of expertise—critically, for the general reader too. Without the hyphens, I myself was asking how to parse this four-word nominal group: is there such a thing as high imaging? Range imaging? In fact, it's imaging over a high dynamic range, yes? Please account for both the needs of non-experts and the directions of WP's MoS. Tony (talk) 14:09, 19 February 2011 (UTC)
Although the change was at first jarring to me, too, I think Tony's rationale is correct. In my experience it is common for engineers—and hence engineering publications—to ignore style conventions, especially when it comes to hyphenation of multi-word adjectives and capitalization. For example, engineers often presume anything that has been formed into an initialism should naturally be capitalized when the initialism is expanded, e.g., "High Dynamic Range" everywhere. To conclude, I think Tony's view is correct that "high dynamic range" should be unhyphenated when it serves as a noun and hyphenated when it serves as an adjective. Robert K S (talk) 15:11, 19 February 2011 (UTC)
Thanks for clarifying the rationale, and I do agree on typographic grounds. I was just concerned by the deviation from the way that practitioners use the term: without hyphens, or just as an initialism, as pointed out by Robert. — Richie 16:56, 4 March 2011 (UTC)
There's only one problem with this explanation: WP:HYPHEN doesn't require hyphenation, it permits it. This is sound; hyphenation (as MOS also says) is slowly falling out of use in such contexts, where genuine ambiguity does not exist. (Tony is, as I would expect, correct on what the syntactic grouping is; but it doesn't need hyphens to support it.) 05:28, 12 April 2011 (UTC) — Preceding unsigned comment added by Pmanderson (talkcontribs)

nearly useless[edit]

I turned to this article for information abut HDR techniques and algorithms. It has next to nothing on such things. I also feel some of the material is misleading or even incorrect. WilliamSommerwerck (talk) 18:26, 22 December 2011 (UTC)

Agree. The big picture / 30,000' view is that it exaggerates differences. That is totally missing from the article. North8000 (talk) 11:22, 24 May 2012 (UTC)
Actually, to refine my comment, the article actually accurately covers the imaging process itself. Such represents the capture and storage of more information than is available from "standard" methods. Where the article goes wrong is that it incorporates creation of printed images in a way that exaggerates such differences as being a part of the process. North8000 (talk) 00:21, 25 May 2012 (UTC)

Seeking consensus on the images used to illustrate the subject[edit]

The quantity of photos in this article is far too great. Photos are supposed to provide concise illustration of the subject, not every possible permutation. I am also concerned about the technical quality of many of the photos, many of which are very amateurish examples of HDR. Please forgive me if I offend the creators of any of these photos. I propose the following:

  • The nav box should be removed as it does not contain the subject article. This should not be controversial and is backed by policy, so I will make that edit.
  • Eliminate the next four photos HDR image + 3 source pictures (Cerro Tronador, Argentina).jpg BrnoSunsetHDRExampleByIgor.jpg Leuk01.jpg New York City at night HDR edit1.jpg in the right column, but consider the top-most photo montage as a candidate for the examples section. The second photo montage has a low gamma and poor contrast; the third and fourth photos have clipped highlights and shadows, and is over-saturated. There are not good examples of HDR imaging. We should find a good representative candidate photo for the article main photo (top right).
  • Completely eliminate the gallery per WP:NOTGALLERY.
  • Keep the Gustave Le Gray photo. Gustave Le Gray - Brig upon the Water - Google Art Project.jpg
  • Keep the first example set of photos and eliminate the rest.
  • The time lapse video may merit discussion as well.

I would like feedback on this proposal and, depending on that, we can either make the changes or move to a formal RfC. - MrX 14:05, 24 November 2013 (UTC)

Under the assumption of silent consensus, I have made some of the changes that I mentioned yesterday. I removed the gallery based on commonly accepted practices and since there is a link to a multitude of HDR images on Commons. I have also removed the second example and formatted the first. - MrX 14:16, 25 November 2013 (UTC)
Belatedly, I support your proposals. I'd probably go one step further and remove the photograph of Leukbach (3rd thumbnail) as, IMHO, it looks like one of those HDR-style images that are popular these days. People already confuse that sort of garish tonemapping (often of LDR scenes) for HDR. nagualdesign (talk) 15:24, 25 November 2013 (UTC)
Thank you for your support Nagualdesign. - MrX 16:23, 25 November 2013 (UTC)
  • I have removed the other two superfluous images. I am going to see if I can find a more representative image on Commons for the lede, but the current one, while not exceptional, is at least technically closer to a representative tone mapped image resulting from an HDR process. I think it would be ideal to find a more recognizable subject, without the heavy orange tonal artifacts, and with a broader range of colors in general. - MrX 21:41, 26 November 2013 (UTC)
Agree. Images are immensely important and useful tool here, but those were superfluous. North8000 (talk) 22:59, 26 November 2013 (UTC)
Thank you. I'm putting together a straw poll of possible lede images, in my sandbox, which I will post here when I'm done. Of course, everyone is free to nominate their own choices as well. - MrX 23:34, 26 November 2013 (UTC)


Lede image candidates - straw poll[edit]

Here are some possible candidate images for the lede, selected based on these criteria:

  • Represents the technique with a full tonal range from light to dark, without large areas of black or white clipping (loss of shadow detail; blown highlights)
  • Colors are not exaggerated, over-saturated or grossly unreal
  • Local contrast is not extreme, especially in skies resulting in a gritty gray look (some of the nominated images push the limit of this)
  • The image is largely free of halos
  • The subject is recognizable
  • Confirmed as having the source images available to prepare a collage as the current lead image has.

For those interested, please vote for the one that you think best represents HDR Tone Mapping, or nominate your own choice by adding it to the gallery. You can also add criteria to the above list if you think there is anything that I missed. - MrX 15:56, 3 December 2013 (UTC)

Votes only (chose one image; comments go in the next section)
  • No. 9 Alfie↑↓© 22:36, 3 December 2013 (UTC)
  • 9 - MrX 22:48, 3 December 2013 (UTC)
Comments

I would oppose any image that does not meet the "sources images confirmed as being available" criteria. North8000 (talk) 16:18, 3 December 2013 (UTC)

While I agree that may useful, I don't think all of the prior lede images had source exposure or were in a montage format. I'm not entirely opposed to it, I just don't think it's entirely necessary. Of course, you can nominate a montage if you like. - MrX 22:48, 3 December 2013 (UTC)
  • I'm voting for 9 as well. I was leaning in that direction, and Alfie's vote has tipped the scales for me. - MrX 22:48, 3 December 2013 (UTC)
Two problems with image 9: There doesn't seem to be any originals available (and I think a montage is the only way to truly show what HDRI is, otherwise you get misconceptions like the one below), and the image shows considerable distortion. That said, I do think that an interior shot with windows may be the way to go. A 'room with a view' is the quintessential application of HDRI. nagualdesign (talk) 04:44, 27 December 2013 (UTC)
Update

There doesn't seem to be clear consensus in this discussion, but what I glean from it is that the lede image should be a montage (or at least have available source images) and that an interior shot would be desirable. I will browse through Commons again to see if I can find any new candidates. Failing that, I may upload one or two of my own. I shot a Greek Orthodox church interior a few months ago and haven't yet post processed it, so that may work. I also have some interior shots of a Ritz Carlton with window views.- MrX 00:44, 2 May 2014 (UTC)

HDR image processed in single file[edit]

HDR image processed in single file by using Dynamic Photo HDR software

User:Alfie66, how could you see this image as bad example? You should discuss with me before you claim as "bad" and revert my edit. --Anton·٠•●♥Talk♥●•٠· 04:36, 25 December 2013 (UTC)

Without commenting on the quality of the image, it has no encyclopedic value beyond what is already included in the article. It also has clipped shadows and highlights, making it no different than a standard exposure image. Technically, it is not an HDR tone mapped image, it is simply a tone mapped image.- MrX 12:31, 25 December 2013 (UTC)
Did not you see other images, which are used in this article, has clipped shadows and highlights? The image is placed as a sample of single HDR processed image rather than different EV value images. Is there any standard for HDRI? --Anton·٠•●♥Talk♥●•٠· 13:02, 25 December 2013 (UTC)
AntanO, IMHO your argument is in direct conflict with the meaning of High-dynamic-range imaging. Starting with the word "imaging" (not merely image processing). North8000 (talk) 13:05, 25 December 2013 (UTC)
Anton, can you be specific about what other images you think are a problem, and why? The idea behind HDRI is to reproduce a broader reproduction of luminosity than afforded by the medium by combining images. The sample that you used seems to simply add some local contrast to emulate the effect. I don't see how that example advances the understanding of the subject.- MrX 14:18, 25 December 2013 (UTC)
Anton, a HDR image (not the tonemapped output) must, by definition, have High Dynamic Range. Which is to say, it must have a greater dynamic range than can ordinarily be captured with current technology. The resultant HDR image cannot even be viewed or printed using current technology (save, perhaps, for some OLED screens with ultra-high contrast ratios). For these reasons, HDR imaging is currently the process of taking several diffent exposures of the same scene, combining them with special software, then tonemapping them to produce a normal dynamic range image that retains detail in the highlights and shadows. Sometimes this produces halos and other artifacts, which have become synonymous with HDR. Processing a normal image to intentionally produce HDR-like artifacts, high saturation and/or high contrast is not the same thing at all. Although the crepuscular rays in this image are pretty, it doesn't belong in an HDR article. nagualdesign (talk) 22:36, 25 December 2013 (UTC)
Hi Anton, see WP:BRD. BTW, if you produced the image with Dynamic Photo HDR, why does its Exif state Adobe Photoshop CS3? Alfie↑↓© 01:16, 26 December 2013 (UTC)
I know what does HDR or HDRI mean? I do not have conflict knowledge of HDR. But, the theory/definition of HDR changes as per many theories. Therefore, I was intended add a picture for “single image processed HDR”, and I was planned to elaborate in the article by mentioning single image processed HDR could be done by special software like Dynamic Photo HDR and in-built features of photo editing software like Photoshop. If anyone feels it should not be here and irrelevant to “encyclopedia”, it’s up to you. I don’t want to insist or beg anyone. --Anton·٠•●♥Talk♥●•٠· 16:49, 26 December 2013 (UTC)
With all due respect, "single image processed HDR" is meaningless. Raw files certainly have a greater dynamic range than, say, jpegs, and processing a digital negative 2 or 3 times to produce different exposures before combining them with software (HDR or otherwise) can help to retain highlight and shadow details, but a raw file isn't classed as HDR by any standards. To put it another way, a 32-bit HDR image has more than 260,000 times the number of possible tonal values than a 14-bit RAW image per subpixel. nagualdesign (talk) 21:34, 26 December 2013 (UTC)
//"single image processed HDR" is meaningless.// If you like to continue your theory, I don't wanna argue further. --Anton·٠•●♥Talk♥●•٠· 03:17, 27 December 2013 (UTC)
I think the reality is that it is no one specific meaning, leaving it to use however anyone wants for whatever their purposes. North8000 (talk) 11:40, 27 December 2013 (UTC)

Better examples?[edit]

Could someone more experienced create better example images? The current examples don't seem to do HDR jsutice, even simple correction of the -2 stop image gives much better results than these two examples.--2A00:1028:83D4:436:CD3B:25AA:61D9:B047 (talk) 12:32, 3 September 2014 (UTC)

I have replaced the lead image per the above discussion. The examples are supposed to illustrate HDR, not necessarily be the most aesthetically pleasing. Perhaps someone will be able to find or produce better examples.- MrX 14:40, 4 September 2014 (UTC)