Showing posts with label Simple Comparison Velvia against simulated DSLR image. Show all posts
Showing posts with label Simple Comparison Velvia against simulated DSLR image. Show all posts

Monday, September 7, 2009

Welcome

Welcome to my blog. In the following posts, I would like to share my experience with converting from digital photography to analog medium format (6x6, 120 film). I will try to answer questions like
  • why should you upgrade to 120 film?
  • what are the drawbacks?
  • what do you gain?
But mainly I will share results from scanning medium format photographs and I would like to encourage you to share your thoughts, too.
Ahrenshoop Velvia 50 EV9 IMG004I chose velvia-film.blogspot.com as a URL because this is easy to remember. I will not only cover Velvia film, but Velvia is of course very popular - for me and many other photographers.

The image above shows a 6x6 photo shot with Velvia 50 film. I shot it a couple of months ago at an EV of approx. 9 at f/16 and 1/2 s. I read the sky with a light meter and added two stops (which was a bit too much). Unfortunately, Flickr does not show its original resolution of 8525x8525 pixels. Thus, I show a 100% crop here (click to enlarge):

Not really impressive, is it? But this is film at f/16 and 4000 dpi. Moreover, the subject is backlit. But the highlights look good, altough the overall image is slightly overexposed. Please do not forget that this is only 0.71% of the original image area! For comparison, I rescaled the image to one third in order to simular a typical resolution of a 12 MP DSLR and sharpened it very slightly. The sensor of the simulated digital camera has about 4260 x 2840 pixels. Of those, only 2840 x 2840 pixels are usable with a square!). This in not really fair because a Bayer interpolating DSLR can resolve brightness with 12 million pixels but every pixel can see only either red, green, or blue. It needs four pixels to see the original color! A better way would be to rescale only luminance to 12 MP, but color to 3 or 4 MP. But anyway, we ignore that for now and give digital a little unfair advantage. What does it look like?
Well, this is difficult to compare ... It's much smaller ;-) Let's compare the cropped image with the crop of the blown
up image from a simulated digital camera. The digital image (mouse over) looks sharpened, more grainy and has much less detail and fewer real colors.





Conclusion: This is a very brief comparison but the difference is obvious.