There's some impressive analysis going on here! Those screen shots are very amazing showing all that data, thanks guys. This does focus the issue only our exposure options and choices, and its very interesting to be gaining more insight into the subtlies behind the ETTR approach and what software can drag out from an image.

Just to clarify, there was some confusion over the DNGH files earlier - Rob originally asked me for an example representing an 'ETTR' type exposure, so I gave him the middle bracket plus 1 higher - these I named 'Darker & Brighter'. I understand the brighter has proven faily unusable on its own.

Then Andrew asked specifically for the lowest exposure bracket (presumably becasue it has become clearer that the sky is most problematic to recover), so I gave him the the next bracket down - so this I called 'darkest'. This is now showing us some impressive shadow recovery capability, even from the lowly K7. But is the IQ anything the equal to the HDR alternative?

The image when opened in PDCU was the same visually as seen on the camera LCD (as I remember), and yes, the PDCU image defaults are as per the camera settings - with the exception of exposure, which always goes to 0 regardless of the camera-set compensation, although the EV remains the same it just centres the adjustment slider.

When shooting RAW I have my camera settings mostly at middle / default values, so there was no significant adjustments applied by PDCU.

The histogram in PDCU remained constant the whole time the file was open.

Guys, I appreciate the input here, and its great to dig a bit deeper into the mysteries of colour channels, 32bit LAB mode and all that!

The workflow of 'IMAGE A)' was as follows : open DNG in PDCU, see histogram which reflects exactly Rob's description above of significantly clipped shadows & blown highlights - made no adjustments - saved as a 16bit TIFF - opened TIFF in Photoshop - made no adjustments - saved using 'save for web' dialogue, choosing 75% size jpg with file size of 1.2mb.

I must admit, as I was not carrying out any editing on the image, I did not check the histogram of either the TIFF or the web-sized image. Its too late now as the TIFF was later used for editing and creating the 'IMAGE B', with plenty of shadow lifting and highlight reduction - and I saved it after this.

So the question is, could the simple process of saving a TIFF and then smaller jpeg have of itself reduced the DR in the image and produced the histogram that Andrew has shown above?

I take the point Andrew about the relative IQ between the '0.5mb jpg & 14.5mb RAW', and I've acknowledged that disadvantage earlier - but the processing differences in results do not appear to me to be of a type specifically caused by jpeg compression, so I would not automatically assume that the file-size difference was significant. What do you think? And you're very welcome to a copy of the DNGs as well to have another go - send a PM with an email and you'll have them

Its excellent to see us moving towards some more specific conclusions and interpretations - much better than some of the earlier throw-away lines implying it was a single shot scene automatically. This thread has been followed in a big way with a huge number of views and some fantastic contributions. I invite many more of those who have been watching to pitch in and give your views - are my judgments on the relative merits of the compared close-ups right? Has my HDR really given the best IQ and most detailed rendition of the scene?

Actually no tripod ... It is all handheld with auto bracketing The battery grip and shake reduction were the only other assistance, so I was very pleased with the alignment in fact.

Yes, it's become an examination of the different results from HDR & non-HDR techniques. Thats fine - my shot is just an example to use in looking at the questions ... its a good example I'd say, as it is complex in texures and tones and incorporates a wide DR. In this context of discussion about processing, no, I don't actually think the artistic value of the image is very significant ... so I find comments about that irrelevant ... and references to excrement unnecessary.

There was plenty of opportunity to comment on the shots merits, artistically & technically, when it was first posted and I did not even mention the HDR. In fact, no one picked up it was HDR ... here were some comments at the time :

There has been no specific suggestions on how to shoot that image better - it already has a very low viewpoint, so it comes down to positioning and foreground I guess.

But I responded to the blunt comments that HDR was not needed. I question this because I was there, I tried single shots and assessed it as beyond the DR of the camera. Andrew, you threw up a single shot as evidence that it was all that was needed. I have been looking at that, and the other single shot examples, closely, and I cannot reach that conclusion.

In fact, to me it is the single shot processings that are pushing the limits too much and causing quality degradation. In Photomatix Pro the images fell very comfortably near to the 'Natural' preset default, with only minor tweaks needed, and it was quite effortless.

I am happy to spend good time on this, and enjoy it, because it will help in future when making exposure decisions and deciding whether it is worth taking some extra time to shoot a few brackets.

That's such an eloquent turn of phrase - I must remember it for when I am next talking about someones photograph.

Well, you did ask the question Now you've got an answer.

Can you imagine the time it'll take for Photomatix to grind through many more? ... DeNoise, abberation corrections, De-Ghosting, aligning - lifes too short.

Andrew, you've made the most of the very uniform lighting there - the skies are nicely controlled. I'd add a touch more contrast to the grounds, especially the 2nd, and a slight boost to lower-mid tones.

I just think its the fully featured paid for version - there is a cut-down, possibly free version without the 'Pro' I think.

I love the crispness & detail, and the way the eye is lead through into the scenes. The long exposure (I'm guessing this filter loses quite a few stops there!) and the IR gives an otherwordly feel. This suits the mono tones - not so sure about the Sepia though ?

Great work

Get a K7 then you can use 5 exposures.