Monday 1 December 2008

Large scale digital photography

My objective has always been to produce quality large scale prints full of detail and high resolution – the question has always been which scale and by using what process? With conventional DSLR images, I was always frustrated by the lack of detail and resolution of the image when compared with large format film images. Over the winter I’ve reconsidered my whole approach to large scale photography.

I found with the Sinar that I was spending so much time setting up shots, that I was missing the light. Further, the logistics and cost of large format film photography made me reluctant to go out and experiment as freely as I do with digital. While some of this frustration may be put down to my inexperience with the medium, I believe the images from Lake Mokoan using stitching to produce large scale images is a compelling argument to switch to digital.

Lake Mokoan is three hours north of Melbourne just out of Benalla on the Hume Highway. The man-made lake is a reservoir for the surrounding farming district developed in the 1970’s by merging two existing swamps. As a result of the rising lake levels, a forest of red gum trees was drowned. Today the drowned red gum forests stand like sentinels within and on the edge of the lake. In November 2008 I took photos at both sunset and sunrise at the same location. I used a large scale digital image stitching technique that I’d developed back in Melbourne using the West Gate Bridge as a subject.

Without wanting to enter into the film vs digital debate, here is what makes sense for me when considering the two formats:

Cost – My initial outlay for the Nikon D200 was more than the cost of purchasing a second-hand Sinar. However, even a second hand set of LF lenses (90mm, 150mm, 210mm) is considerably more than the equivalent my set of digital lenses (18-200mm zoom and 50mm prime). With digital there is also an initial cost in purchasing a computer and software. Unless one is going to stick to the darkroom (and I never was), this cost is also shared with the large format film scanning workflow.


So although the outlay for the equipment is roughly the same, it is in the ongoing costs that digital is so efficient. With the cost of storage coming down all the time it is possible to purchase an 8GB compact card for less than $50 and 1TB HDD for less than $200. In contrast the price of large format film consumables is expensive:


  • Film: $75.20 for 10 sheets of Fuji Velvia 100 @$7.50 per sheet
  • Development - @6.60 per transparency
  • Scanning - 2040 PPI 16Bit 500MB @$25 per file

If every shot is bracketed (even the pros do this) at 1/3 stop then a single image costs the following:


3 x sheets @$7.50 = $23.50
2 x development @$6.60 = $13.20 (this is assuming that the 0EV shot is developed first and a bracketed exposure is developed second only if required)
1 x scan @$25 = $25
Total = $61.70

Considering that there are also shots that do not make it to the scanning stage, for each failed image there is the following cost:


3 x sheets @$7.50 = $23.50
2 x development @$6.60 = $6.60

Total = $30.10


At Mokoan I processed six images, assuming that I could have set-up the Sinar fast enough to capture the rapidly changing light, this would have cost me $370.20 for the developed images and at least another $180.60 for six rejected shots, assuming for every processed image there is a rejected image (in reality the ratio is likely to be higher – 3:20 images at sunset) - for a total of $550.80.


For a commercial photographer working on behalf of a client this may cost be justified. For a hobbyist, or semi professional these costs border on delusional to justify. This also assumes that the client is willing to wear the additional costs for the perceived increase in quality of the large format film image.


Time – On top of the costs above there is also the time to process the large format film image and the digital stitched image. The elapsed time of capturing the image, to develop, to scan and post process can run into weeks. While the capture of multiple digital images and the stitching time consuming, the lapsed time is only a fraction of the film camera. In addition there is also the logistics of buying the film, taking the film to the lab for development and scanning (may require repeat visits if bracketed images are required as well)


Flexibility – In landscape photography at twilight the light can change in an instant, the view camera is not flexible enough to be relocated – these two photos were taken within minutes of each other – there’s no way I could have setup the View Camera in such short time, focussed, loaded the film and bracket shots.


These two images were taken within minutes of each other:

Quality – There’s no double that a well exposed and scanned 4x5 is a quality image, the degree of detail in the film image is superior. However, I believe the combination of a fixed focal length lens (Nikkor AF 50mm f1.8), mirror up, tripod, RAW and cable release can come close to matching the output of a scanned 4x5. A double layer stitched image of 12-22 exposures equates to a 500MB file which is roughly equivalent to a 4x5 scan. Both formats have limitations and compromises have to be made. I’ve made the decision to sacrifice some detail of the large format film image for the flexibility and cost savings of the large format digital image. If I had unlimited time and money I might consider the large format film process over the digital process - but I’d still mourn the loss of images due to the setup time required for the View Camera. Others may choose differently.


Exposure – This is where digital comes in to its own. I can check the exposure on location using the RGB histograms and adjust the shutter speed as required. With the Sinar I had to bracket at least -1/3 and +1/3 stop as a minimum, that’s an extra cost for film and processing and still not have any guarantee that I nailed the exposure. With digital I point the camera at the brightest part of the image, usually the sky, and adjust the exposure until the highlights to the right in all three RGB histograms are just short of being clipped. If the sun is within frame I allow this part of the image to be clipped so as not to clog the shadows to the left.


By using the 50mm lens I ensure the sharpest image with no barrel distortion or wide angle diffraction. Up until a few months ago, frustrated by the Sinar’s inflexibility, I was itching to upgrade to a Canon 5D Mark II in the pursuit of sharpness and resolution. Now I’ve discovered digital stitching I’ve realised that my Nikon D200 is “good enough.” At 15MP per raw file my Dual Core PC is already struggling with the 1/2GB PSD files. The Nikon D200 is a 10MP camera as opposed to the 22MP of the Canon 5D Mark II; I’m afraid to think how large the resultant PSD file would be. Besides, I love the metering of the Nikon's and the usability.


There is no doubt the process of using the View Camera has taught me valuable lessons that I would never learned using digital. The manual process made me think in new ways about the relationship of aperture, ISO and shutter speed as well as focus. In many ways it has simplified my digital photography technique, I now use manual process for both exposure and focus control. As I’m shooting RAW, I can forget about filters, white balance, colour and saturation at the time of capture. With digital I also have the option of capturing HDR images that would never be practical with film.

2 comments:

Anne said...

Hi,
Love the concept of Landscape Photography.
It’s beautiful.
Very good blog as it involves all the technical details of Photography.
Helpful for all those learners who want to pursue a career in Photography.

Andrew McDougall said...

Thanks for the comment popi.