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A taught on High Dynamic Range Imaging

Digital camera's main weakness lies in its limited dynamic range which usually spans between 9 to 12 stops depending on the quality of camera's sensor.  

Several attempts has been tried to overcome this problem such as using Highlight Tone Priority and Automatic Lightning Optimiser which widens the Dynamic Range of Canon cameras or ADR which widens the dynamic range of Nikon cameras.  However that requires you to change the camera!

Cheaper way compared to changing camera to get higher dynamic range can be accomplished by using Natural Density Graduated filter (ND Grad filter), which is half dark and half bright.  However due to its shape, some subject such as Candi Mendut is not compatible with ND Grad filter.

WWhile other way can be used when the subject is within the flash range (read: near) is by using fill flash.  Fill flash will help brightens dark foregrounds and retaining the proper exposure of the image's background.  Fill flash can help balance the lightning on this picture, therefore we don't need to use HDR special software. 

To overcome this, photographer usually using trick such as deliberately underexposing the image by 1/2 to 1 stop to capture the highlight and then lightening it later on the computer (since digital camera is good in capturing shadows, therefore this trick can work well).  For example my Candi Mendut shot is taken this way.

 Sunrise in Mendut

HDR imaging technique is an attempt to improve the dynamic range.   What HDR imaging did?  It will greatly increase the dynamic range of an image.   How to do it?  The simplest way is by, making 3 shots at normal, under and over exposure of the same scene.  Camera's exposure bracketing and tripod help this.  Then use Photoshop to do surgery on the image.  Please open this excellent website by Andreas Tofahrn on steps to do HDR or DRI imaging manually! 

Other way to do HDR imaging is by using a special software such as Photomatix by HDRSoft.   Please open Gatot Jaka Timur's multiply page to see a lot of HDR images created using by those software!  From what I know, his pictures are very good and he is a HDR lover!

TTwo of HDR imaging's greatest weakness lies in its slow process since requires 2-3 shots, therefore only works for still or almost still subject and requires a long computer workflow, which I have no luxury of doing that.  

So, now the question is: can an image with normal dynamic looks better than with HDR? Absolutely!  HDR will only widens dynamic range.  However colour balance and composition is the strongest points that make a good photograph.  New York City Night time cityscape was awarded second place in Picture of the Year 2007.  It boasts HDR imaging and properly executed, therefore increasing the image's overall strength.  This image of Persepolis, Iran is perfectly executed in HDR therefore resulting beautiful image.

Is an image with HDR always looks better with the very same image without HDR? Not always, when incorrectly done, the image loose its dark shadow and blindingly bright highlights, therefore the image will looks less contrasty and lost its 3D looks, which we perceive from contrast.  Therefore resulting in flat image and boring image.  This Wikipedia image is very good, however I felt that the road, house, monument, castle and sky fights each other trying to attract my attention.  This therefore weakens the overall strength of the image!  FYI, I've seen an incredibly boring and flat un3D images resulting from HDR, however I've forgotten where do I saw that image!

Is it good to have an image that have some overexposed area and under exposed area?  Well, photography is art, it truly depends on your taste about an image.  Me, myself prefers things to be done how it should be done.  A blindingly bright highlight should be very bright and fine to wash out.  I don't want so see any details from there. While a dark things such as road asphalt should stay black, and need not be greyish with all the details.  The Colour Explosion image is very nice, however I feel that the housing shouldn't be that bright, since It distract my view from admiring the beautiful colours of the sky.  Well, cropping the picture to 2:1 aspect ratio, retaining the full sky and removing half of the houses picture will render this image much better!

Just as a reminder:  too much detail will destroy an image's strength by distracting the viewer's eye away from the image's main attraction.  This is also the reason why photographer deliberately removes background detail of an portrait (a face close up) by using wide aperture then resulting in bokeh for out of focus background, therefore resulting in one detailed subject only with blurry background!  Effectively removing all the background details.

II only use HDR to preserve highlight in a very contrasty scene.  I rarely use HDR since most of my images are properly exposed and even rarer if any requires to have HDRed to emphasises its strength.  That's means for most of my photograph HDR only benefits in retaining the colour a little detail such as red/blue streetlights.  While I love to have them coloured, but having them white is not a problem for me.  I don't thing it is worth to take the painstaking HDR workflow just to fix it a few minor coloured dots of streetlight!

Anyway I prefer to use Canon's Highlight Tone Priority or Nikon's ADR in more advanced cameras.  What a pity my camera does not have it, probably because of its 12-bit processing! 

The conclusion is: when you have the time luxury, loves HDR image, loves the process, and can do it properly, then feel free to do it!  Photography is art!  It all depends on your taste!  As long as you love it, just do it!  And quoting from Tofahrn's last sentence about DRI (HDR) "DRI is more an art than realism and so you're free to form the result based upon your personal taste."  In simple words, just don't care about what others or me say, since if you love it, it is good for you! 

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