Monday, August 17, 2009

HDR Comes to the Grand Mosque of Abu Dhabi

Prayer Room at Grand Mosque - 5And1more
(NOTE: all the photographs featured in this entry are from the Sheikh Zayed Bin Sultan Al Nahyan Mosque in Abu Dhabi, United Arab Emirates.)
Before I finish the ongoing discussion of organizing photography, I am taking a break to briefly look at some High Dynamic Range (HDR) photography.  HDR photography is a process that lets you reproduce all the detail your eye can see normally lost to the shadows or the highlights in photography.  Not surprisingly, your brain and your camera record visual information differently.  Your eye is a much more capable camera than your DSLR, and your DSLR is very handicapped at replacing the function of your eye.  The HDR process helps overcome the handicap or physical limitations of your camera.
As you look at a beautiful sunset, you are able to scan the scene in front of you – left and right, up and down – and your eye adjusts to the bright and dim areas allowing you to discern details in both.  With a single photograph, your camera cannot collect and ultimately reproduce all the information your eye can.  Thanks to HDR techniques, you can overcome this limitation.  To put the details of the highlights as well as the shadows into a finished photograph requires that we take and combine multiple exposures to capture the richness hidden in the shadows, the full breadth of mid-tones, and the fine details often lost in the highlights.
Here is an example of a photograph I made using my normal setup and post processing methods:
Prayer Room at Grand Mosque - 2
This is not a bad photograph.  It is well composed and relies on the symmetry of the columns and arches, repeating patterns and leading lines to bring interest and guide the viewers eye.
Here is the exact same shot rendered in HDR and composed of four separate exposures:
Grand Mosque Prayer Room HDR-2
The HDR image is more vivid, vibrant, colorful and detailed (for instance look at the difference in the details on the main chandelier and in the top of the blue dome at the top – center).  Many of the details lost in the first photograph leap out at you.  The HDR image draws you into the grand hall and begs you to explore all the details.
Composing a photograph such as this begins with multiple exposures taken from a tripod.  For me, multiple exposures usually means 3 to 5; one exposure as I would normally compose the shot, then by adjusting shutter speed only (maintaining ISO and aperture at the same setting), take one or two over exposed shots (consecutively by one f-stop each) and one or two under exposed shots (again consecutively by one f-stop each).
I have been making HDR photographs for quite some time.  But until recently I was making HDR images the brute force way.  Until the introduction of currently available high quality HDR software, these images were prepared in Photoshop using a bunch of layers to pull the desired details out of each exposure.  I won’t get into the details, but imagine having three shots of the same image at different exposure values.  In Photoshop you can combine the three photos and select the portions of each photo that are optimally exposed (bringing out shadow or highlight detail and combining these elements with the “spot on” exposure).
I was never satisfied with the results of the HDR function built into Photoshop so my work always relied on the very tedious process I just described.  With the advent of such specialized programs as Photomatix Pro (see www.hdrsoft.com), the tedium is gone, and the magic happens with a few simple slider bars to adjust the level to which the highlight and shadow details are balanced.
There are a number of people embracing this type of photography whole heartedly.  Personally, I love the added level of creativity and opportunity I now have at my disposal.  My only reservation is that too much of a good thing, can be, well, too much of a good thing.  With HDR, “too much” comes in two different forms:
  1. Shooting every shot in HDR – HDR is great, but “too much” in the form of quantity is something to guard against.  All things in moderation. 
  2. Pushing the software too far - The leading HDR programs give the user a great deal of flexibility to explore some extreme applications of the process.  Pushing the capabilities can yield some very interesting results.  Unfortunately pushing the boundaries can also lead to some very strange, even cartoonish results.  Again, I recommend restraint.
Here is an example of “too much” manipulation:
Grand Mosque Prayer Room HDR
While an interesting result, in my opinion, this has gone too far.  The next photograph, using the same original exposure set, is processed a bit more conservatively and reduces the surreal cartoonish effect while maintaining the details (likely appreciated much better in a larger view format).
Grand Mosque Prayer Room HDR-3
One of the fun things about the HDR software is that you can create virtual HDR images from a single exposure.  Like with multiple exposure HDR images, this can be accomplished through a great deal of tedious work in Photoshop – my preferences lie on the side of efficiency.  The following shot of a minaret with the sun in the background originally appeared (as I intended) as a silhouette. After processing in Photomatix Pro, we can bring back a great deal of detail as well as balance.
Minaret in the Sun
Here is the same shot that instead of being a single exposure virtual HDR, is a two exposure HDR.
Minaret in the Sun-2
As you can see, these are very different photographs with a great deal more detail exposed in the 2 exposure version.
The remainder of the HDR photographs are presented without comment…simply for your enjoyment.  They are HDR photographs of the exterior of the Sheikh Zayed Bin Sultan Al Nahyan Mosque.
_MG_7115_6_7
Grand Mosque at Night HDR
Grand Mosque Corner HDR
I hope you learned something about HDR and enjoyed the results.
Go make some great photography!
Craig

1 comment:

  1. Craig, amazing images! Though you sent some to me before (think the second from the bottom was black/white), they're great to go back to. What access! The very first shot is incredible.

    Cheers,
    John

    ReplyDelete