What next for digital cameras?

What's the next big thing? Improved noise levels? Better sensors? Motion reduction and image stabilizers? Perhaps, but these things are boring. Merely evolutionary changes, not radical enough to garner much interest.

Things looked boring until a certain remark by Herbert Keppler of Popular Photography magazine piqued my interest - a remark on High Exposure Latitude sensors by Canon. Few picked this up though, even established forums did not speak much about it. All is not lost though, here are some links which speak about this:

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00FfVV&tag=

http://www.popphoto.com/idealbb/view.asp?topicID=47746

Just a summary here. Digital camera sensors are almost as unforgiving as slide film - can't make too big an exposure error, else your picture will be shot. This is what they call low exposure latitude - no margin for error.

Print films like Fuji Superia gave at least 4 stops of exposure latitude, if you screwed up, all you'd need was to print 3-4 stops lower or higher exposure to remedy the error. And the result would almost be as perfect as if you had the exposure spot on. It would be excellent if digital sensor technology had this kinda latitude, and with instant preview after shooting, the percentage of usable shots would be of a higher ratio once high exposure latitude were possible on digital camera sensors.

The limitations of digital camera sensor technology was the same, whether using CMOS or CCD sensors. Though Herbert Keppler were to term this technology as increased exposure latitude, it would be easier to find out more about this technology if you were to use the equivalent `new age' term - `High Dynamic Range' or HDR. High Dynamic Range is roughly equivalent to Increased Contrast Ratio and is roughly equivalent to Increased Exposure Latitude - in this perspective all three terms refer to roughly the same thing.

After doing additional research, it was clear that Canon was not the first off the block with this technology. It was Fujifilm with the FujiFilm FinePix S3 Pro - employing 2 kinds of photodiodes in their SR CCD sensor, ones with high sensitivity (S) and low sensitivity (R) on each pixel. With the image processor combining image data from both pixels, the system can increase the dynamic range to 400% of normal sensors' 1000:1 dynamic range, which Fujifilm equates to 2 stops. More information here: http://www.letsgodigital.org/en/camera/review/30/page_1.html

This method is similar to that of HDRsoft's implementation - www.hdrsoft.com - where a camera takes 3 pictures of a similar scene, one underexposed (to better capture highly illuminated (bright) nuances), one normally exposed and one overexposed (to better capture low-light (dim) nuances, and combine all three into a HDR picture, then tone map the HDR to normal dynamic range, with the high dynamic range compressed but yet preserving the enhanced highlights and shadows, for that incredible effect you see in the picture at the beginning of this post.

The only thing not going well for Fujifilm is the cumbersome dual photodiode system, which may increase diffraction because of the interference of the light wavefronts. I have not seen this phenomemon but it has been reported in the forums as `chromatic abberation'. Unlike purple fringing, this chromatic abberation has colors of a rainbow, much like you see an oil film on water - classic evidence of wavefront interference.

Keppler says that Canon's first implementation would be on a SLR, and presumably it would be in a single photodiode to span the entire increased dynamic range. And His Venerableness says that this will happen in 2007 while Canon soldiers on with the EOS30D the entire 2006. So from this statement, seems that the world's first fully integrated high dynamic range mainstream sensor will be APS based.

So, DSLR folks, you can do your bit by not buying a 5D or 30D today, to force Canon's hand. Once a mainstream HDR DLSR comes out, you can bet Canon's lead over everybody else (yes, including the lead over Nikon) will increase to an insurpassable extent. And that would be the time I sell my entire Nikon lens collection and experience the joy of cheap (relatively) USM and IS.

Problem is that the initial use for printed photos will merely be that of increased exposure latitude since print film sucks at showing high dynamic range images. LCDs are slightly better but their dynamic range is only about 700:1 for current implementations (LG will have 1400:1 later this year in August). So tone mapping would probably be the only way to see HDR, and many will object to the the highly artificial looking tone mapped images, which to the film crowd, would be SUPER HIGHLY SATURATED VELVIA.

This is gonna be exciting.