As I understand it, HDR is just a clever(?) way of combining exposures to reduce the overall contrast, so that it fits in the space available to display it. The HDR crop of the glass seems to have much lower mid-range contrast, which is an undesirable side-effect. I don't have a copy of Photomatix, so do not know whether that is an inevitable outcome of the HDR process. If it is, then I remain unconvinced that HDR has any real value.

Andrew

Nigel was kind enough to email a full size JPEG that was created using Photomatix from half a dozen DNGs that I made available to him. I have, therefore, had the opportunity to make some close-up comparisons, which I hope you find interesting (all 100% crops).

Firstly, the stonework from the window:

This is from two exposures combined (crop/paste) ......



This is from Nigel's HDR image .....




Secondly, some of the glazing .....


This is from two exposures combined (crop/paste) ......




This is from Nigel's HDR image .....




My preference is for the non-HDR images.

Andrew

For me, there is nothing in this image that shouts HDR. If the question had not been asked in this thread, I would not have suspected that it was HDR.

Andrew

I think that is pretty much where I am too. Maybe I drifted off the track a little at the start of the thread, but fundamentally I agree.

Andrew

Just for interest, I had a look at the preview images in several of the RAWs and discovered something interesting - a bit of detail here and there in some (overexposed by 3 stops compared with the single exposure version) that isn't shown in any of the non-HDR crops I posted earlier. So ....... I selected a couple of RAWs and ran them through LR/Enfuse again, with this result.




There is some leaf-pattern in the blue/purple below the end of the stick - and what looks like fencing (possibly external to the church) in front of the face.

This raises a question in my mind - if detail exists in an area of the HDR image that isn't visible (or is less obvious) in the image generated from single/double exposures, should that influence judgements about the worth of the HDR version?

Thoughts on a postcard .........

Andrew

Nigel, this is the middle of the three closer crops that I posted on the previous page, can you post a similar crop from your HDR version, so we can see them close together?




Andrew

An interesting result and better than the HDRs I generated using LR/Enfuse. The glazed areas seem short on contrast compared with the single/two exposure versions and yet the stonework seems to have too much contrast which almost shouts HDR at you. It's not overtly cartoony, but the Photomatix HDR versions still look a bit artificial to me. I don't have a copy of Photomatix, yet I don't feel my wallet twitching.

Ultimately, I think the two exposure version gives the most flexibility for optimising the appearance of the stonework. Having said that, for this image, I think the single exposure option can provide a perfectly acceptable result, without introducing excessive noise when the shadows/blacks are lifted a couple of stops. If I had taken the exposures with my K200D rather than the K30 that might not have been as true. If I get the opportunity to go back again to All Souls Church, for this kind of image I will probably take two exposures for the stained glass windows - one optimised for the glazing and the other two stops up, rather than taking half a dozen with HDR processing in mind.

At some time, I do need to have another play with the LR/Enfuse plugin because it also supports merging images to maximise detail i.e. focus stacking - but for now HDR processing using Photomatix or LR/Enfuse stays on the back burner.

Andrew

Indeed - and it was really quite dark in that corner of All Souls Church. The closer crop "lifted by two stops" or maybe a little darker is how I remember it looking.

Andrew

Just for interest - and because I have a feeling that Nigel is going to tell me shortly that he thinks the stonework is too dark - herewith three smaller crops from the processing of a single RAW with the stonework lifted by one, two and three stops.

Lifted by one stop .......



Lifted by two stops ......



Lifted by three stops ......



Of course, these are just examples and the stone exposure could be higher, lower or anywhere in between. Its interesting that, for this image, even with the stonework lifted three stops, there is no *intrusive* noise.

All I did here was use an adjustment brush to select the stonework - and then twiddle away with a few sliders. As I like working in Lightroom, using a single image is likely to continue as my preferred approach, unless the dynamic range really is such as to make that impossible - which it doesn't seem to be here for the K30.

Andrew