Chester Cathedral - The Nave Ceiling (17x exposure HDR)
I have tried to do this shot a few times in the past and never really managed to nail it. I had problems with getting the exposure right, getting the orientation correct and always ended up fixing and cropping things in post. This time armed with a new android app called “DSLR Controller” and a bit of practice with this kind of shot, I aimed to get it right.
DSLR Controller is an app that runs on my Samsung Galaxy S2 android phone and connects via a USB “On The Go” cable to the standard USB cable that came with my Canon 5D Mark II (it does work with many other Canon cameras). The two key features that helped with a shot like this are:
1) Being able to use the phone screen in “Live View” mode (helped with alignment)
2) Being able to take more than 3 exposures in Auto Exposure Bracketing mode (helped to capture the massive dynamic range here).
The image above doesn’t show it but the conditions for this type of shot where not ideal. It was taken just before 5pm on a very bright sunny day and the sun was shining in through the windows. Any other “normal” non HDR shot would have been completely blown out and unusable.
The shot here was actually a 17 exposure HDR image with the camera set to RAW, f5.6, ISO 100 and the bracketed shots went from 1/8000sec (-8 EV) to 8 seconds (+8 EV). The resultant images where imported into Lightroom and then exported to Photomatix to generate the HDR. No cropping of the final image was done.
I have tried generating a couple of HDR images using a smaller number of the 17 images captured but it does become noticeable around the windows that there is detail missing. I am not sure if I’ll be making a habit of this as one major issue with this number of shots for one image is that it uses around 600Mb of disk space for the 17 x raw files and the exported Photomatix TIFF file!
For more information about DSLR Controller see the links:
UPDATE 9th Aug 2012:
This image was submitted and came 2nd for Martin Baileys assignment "Geometry", for more information see the links: