THE HDR ADVANTAGE

I've been comparing more closely 4 different versions we now have. It is probably obvious I guess that I am unlikely to be persuaded that the HDR treatment here has not produced the best result - both technically and in terms of the look. Rob & Andrew provided expertly adjusted alternatives trying to eek out the most from a single exposure, and I tried also with this and produced a blended version with the separately adjusted sky. But I feel it was futile - I still believe that the high DR of the scene has only been able to be accurately reproduced with quality and detail by means of the HDR process using the full 5 bracketed images.

Andrew may fairly claim he was at a disadvantage, because he only had a web-site downloaded image to work with, whereas the others were initially produced from the RAW. But the jpg Andrew used was initially a 75% reduction from full-size , a 1.2mb file, so a good starting point and I did not notice any obvious quality loss on the website.

But here you can all check out more closely why I think this is the case, and you may agree ... or you may come to a completely different conclusion!

Here are the 4 alternatives on the table :


1) Nigels HDR






2) Nigels Blended (single file but with separately processed sky)





3) Robs Single File







4) Andrews Single File






I have downloaded all these from the website and used these downloaded files to ensure they are all the same size. I have cropped in on 3 different areas and resaved the crops for close comparison.


A) MID RANGE SECTION

A 1) Nigels HDR





A 2) Nigels Blended





A 3) Robs Single File





A 4) Andrews Single File





Here the HDR and Andrews seem the most similar, with higher contrast and detail than the others. The HDR has finer & sharper detail I think, and more colour and deeper black in the shadows. It also has a wider range of colours. Robs image is hazy and lacks depth, and has the least definition here, and my own blended image looks pixellated but over-sharp. The HDR wins here for me.


B) SKY DETAIL & FAR DISTANCE

B 1) Nigels HDR





B 2) Nigels Blended





B 3) Robs Single File





B 4) Andrews Single File





Here Andrews is the brightest, with the highest whitepoint and the least contrast within the sky area - the shadows are the most noisy. Robs is less bright, but the highight cloud areas are blown out with no detail - there is better distinction between the clouds. My own blended version looks jagged and over-defined. The HDR version IMO wins again here, with good cloud detail but still soft fluffy edges. There is better detail in the forest on the the horizon here also.



C) FOREGROUND DETAIL AND TREES


C 1) Nigels HDR





C 2) Nigels Blended





C 3) Robs Single File





C 4) Andrews Single File





Here the 2 closest in colour and detail terms would be the HDR & Andrews, both a bit richer in colour and with more discernable fine detail in the grass and pathway textures. The HDR wins out here also IMO with a wider range of tones in the tress and foliage
and better texture detailing. Robs has a smoother appearance with flatter deep shadows, but is the brighter with a high pitched pathway tone. The HDR presents the most even balance of brightness values throughout ths crop. My own blended version looks flat and has the same slightly jagged & oversharp appearance as it showed in the sky as well.

OK - thats how I'm seeing these comparable images. I can see no basis to any claim that a single shot can produce a better rendition of this complex scene that the original HDR choice I took. Overall I see the HDR beating the others on all fronts - tone, texture, colour. I'll be glad to hear any other ideas once you've taken a close look also.

It would be great to work together of course, I'm sure it would be enjoyable. But really is there any contradiction here? I don't deny that focussing on the artistic will ultimately lead to better results than less lower quality artistic results 'boosted' by processing - I don't believe that anymore than anyone else. Thats why I keep saying I'll go back in differing conditions and try more angles and experimenting with the actual shooting.

Just telling me to focus more on the artistic does not mean that the one shot on the table cannot have its potential boosted by the best type of processing available does it?

What has thread has become (don't you love the way it can morph from one thing into another) is an examination of how a single shot stands up to different processing approaches - thats fine, it is fascinating. In this context, we have one shot and differing opinions on how it needs to be processed. We can't change the shot artistically - just look at how the different processing techniques can bring out what qualities it has - or supress them.

Thanks Rob, thats a real contender! I take on board Andrew's point above about the difficulty of pixel-peeping on relatively small files, but I do think I can probably draw some conclusions on the main differences. I've got the images downloaded and will take some comparitive looks and report back.

If any of you can take a look at the new HDR version above and compare it to any of the single shots I'd love to hear your views.

I've now gone back to the original HDR image and carried out a few more adjustments, taking on board a few of the comments that have been made. I have boosted mid-tone contrast a touch, burnt in a few shadows and given it a boost of micro-contrast and detailing. I hope it will become the new contender for top spot!!


1) NEW HDR VERSION

We are limiting it to those aspects though - that's perfectly valid. Its only a discussion on the merits of some different treatments, and it stems from my own assertion that the DR of the scene demanded an HDR approach - I think that's still up for grabs. It depends on how you ultimately judge the result ... my own feeling at this stage is that the softer toned HDR makes the most of it artistically as well as technically. But its great to have other viewpoints as well.

Don't worry, you'd have to work rather hard to offend me, rest assurred - more likely just encourage me further Look, truth is yes, personally I am pleased with this series of photos - for me they are a quality record of what I was trying photographically that morning, and the processing has brought out what qualities are there well. But at the same time I am not unrealistic ... I'm not planning on putting any of them in for 'Landscape Photographer of the Year' - the location is limited, but I will enjoy going back in different lighting and making some new artistic choices.



I think we just need to check closely the quality at the extremes, such as the cloud highlights and deep shadows. The clouds are going to be key to it I think, as really this scene does not demand perfect discernible details in the deep shadows ... a bit of pitch black here & there is OK I think, and probably will help add some overall depth to it.

I cannot conclude anything of the sort so far ... I know by instinct I prefer my own HDR as viewed in total - I have a 'layperson' here who didn't know anything of the origins of the images or which was 'mine' and there was no hesitation at all in picking out the HDR as the one, so I don't think this is a foregone conclusion.

And we haven't even really looked in any detail at the actual quality of the detail and textures at both extremes - I'm going to check this soon, but initially it seems to me that the HDR has a softer appearance, more 'fluffy', ifs that's a valid quality

I'm going to go back to the HDR TIFF and try and bosst mid range contrast and carry out some more refined and targeted work - lets see if that may change things ... art not algorithms.

This raises some interesting questions, and I'm grateful to you all for the help and additional input here. I'll try and clarify as much as I can:

The 'IMAGE A' jpg that Andrew has used was produced from the DNG I provided to Rob, the one named 'Nigels Riddlesdown Darker' (ie the less exposed of the two). I created IMAGE A in PDCU and PS from this DNG by simply opening the file and saving it with no adjustments ... first a 16bit TIFF from PDCU, then the TIFF into PS and saved as a 'web-sized' jpg, again with no adjustments. I can confirm that this file displayed a significant clipped histogram both in PDCU and PS.

Now, this is where it gets more complex - I have just taken this DNG and opened it is PS (CS2), (a more similar process to Andrew's), and the ACR defaults upon opening have reduced the histogram end points and pulled the DR down - this has happened as a result of ACR default settings (the auto exposure / auto contrast boxes were ticked). So ACR has carried out auto processing before I even started. Unticking these auto boxes has restored the previous histogram shape I had seen in PDCU -ie with significant clipping at both ends. Newer versions of ACR may have similar or slightly different default operations.

This may be the reason that Andrew has interpreted the file as not clipped? The real question though is what effect on quality does any processing have when the shadows are brought up and the highlights reduced, and which processes are preferable, which may depend on our own personal artistic priorities.

I've downloaded Andrews edited jpg and I see the histogram is exactly balanced with the black & white points just touching the ends, consistent with precise levels corrections. I've done the same with Robs 2nd jpg there, and I see that it has a more compressed DR, with the end points at about 24 / 224.

Finally my own HDR image (taken from the final jpg for best comparison) has a wide range, a high sloping bell shape with the back point extending slightly upwards and the whitepoint touching the end. So a slight clipping remains, but it has the wider DR overall.

So that leaves the question of preference and the 'look'. David Storm has already made his choice - is that to be the popular view?

Rob that certainly is some closer competition ... The nd grad was not an option due to the specific lens, but clearly if it was an option then it would resolve the sky problems. I'm not so convinced about the ground texture and visible dr. Thanks again for the extra work there.

Andrew, thanks also for your attempt there to answer the question. I'm not sure its as clear cut as you imply? But maybe we are selling the K7 short? That exposure must be , what, 2.5 stops below a centred meter? I'll reserve any proper pixel keeping though till tomorrow if I may, due to only having a smartphone available tonight. Thanks again for getting involved.

now I never thought I might provoke that .. So I've been told so far to buy a K5 & a set of Hitechs - this is proving to be an expensive shot! But at least we agree that such a scene is beyond the DR of a sensor such as that in the K7 - I believe many would not.

gwing wrote ... 'Well I think my K30 give me 1.5 stops extra DR compared to the K7 which is going to be really valuable. Whether that would actually be enough to bring all the highlights back into range or not isn't provable'.

So not really provable about a K5 either then?

davidstorm wrote.. 'I do prefer single processed shots, but that's just a personal opinion, there's nothing wrong with your HDR shot'

Well here's a chance for us to compare ... we have gwings there already up above.


Here's my new takes on it - first there's the two mid range brackets unadjusted for reference - that's what you get from a single shot out the camera. Then optimized processing for both through ACR & PS, (these represent the best I could achieve with a single exposure), and finally a blended version of the best single shot plus that shots sky processed again independently :


IMAGE A) Mid Range (Darker) bracket - PDCU unadjusted








IMAGE B) Mid Range (Darker) bracket - optimized processing







IMAGE C) Mid Range (Brighter) bracket - PDCU unadjusted







IMAGE D) Mid Range (Brighter) bracket - optimized processing







IMAGE E) Blended version of optimized ground & separate optimized sky







And finally here's my original HDR version ... I guess I don't need to spell out which one I think is a better more 'natural' reproduction of the scene ....







For me, both the single shots, (even the darker which was way too dark for the shadows), made the sky impossible - that is the DR being exceeded. The blend was more successful, but the sky was impossible to bring down with real quality. Only the HDR process (which had 2 further darker exposures,good for the sky but black on the ground) could create an acceptable image for me.

I don't remember anyone mentioning it before - thats a very practical range I think. Will check it out. And a great test shot!