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View Full Version : Film Resolution vs. Digital Resolution


Jason Dunn
03-02-2004, 04:00 PM
<div class='os_post_top_link'><a href='http://www.tawbaware.com/film_digital.htm' target='_blank'>http://www.tawbaware.com/film_digital.htm</a><br /><br /></div>"I'm not a film camera user, but I'm always intrigued when the question of how many megapixels does a digital camera need before it is "as good as film" is asked. Very often, the discussion seems to devolve into name calling, or subjective claims...either way, nothing gets resolved. In order to avoid further name calling, this page does not attempt to answer that question. Instead, this page presents a comparison between one of the latest digital cameras (Canon D60) which produces a 6 megapixel image, and a high quality scan from a film image. The purpose of this page is to add some illustration to the (typically theoretical) discussion about film vs digital."<br /><br />This is a fantastic article, even though it was written back in August of 2002 - I'm a big believer in digital photography, and dislike the attitudes of "35mm snobs" who believe that digital isn't a viable option for getting beautiful pictures. 35mm users are more than welcome to use that format if it allows them to capture the images they want, I'm not arguing that everyone needs to go digital, but the quality level of digital images has evolved to the point where it's not longer an issue simply of quality. In fact, with the lack of graininess that accompanies 35mm photography, some would argue (myself included) that digital pictures are of a higher quality than 35mm film. There's <a href="http://www.normankoren.com/Tutorials/MTF7.html">another excellent article</a> that discusses this issue as well.

Crocuta
03-02-2004, 05:28 PM
This is such a complicated topic that it's really hard to make a definitive blanket statement. There are just too many variables. For film, are you using Kodachrome Professional 25 or their all purpose Kodacolor 800 for compact cameras? For digital, are you using your cell phone or a high-end Canon or Nikon? What are the lighting conditions? How much contrast? How fast is the subject moving?

I thought the Tawbaware article was relatively meaningless, since all he demonstrated was that it's possible to create that result. I don't for a minute think the author was trying to be deceptive or anything, but a different choice of options could well have created a different result.

The Norman Koren article, on the other hand, is excellent. He really gets into the matter in detail and points out the advantages and disadvantages of each. Of particular importance is his discussion of the 'four pillars digital camera image quality' because that's where you can compare the things you want to do photographically with what digital can do for you.

For myself, I'm still mixed. I use digital for more casual work (and DV for video) and still use film for my highest quality still work. In the past year, this has become more a financial decision than one of quality. I can't afford to buy a new high-end digital camera every couple of years, so when I replace my SLR with a DSLR, it will have to be with one that will last me for several years. I just have a feeling that DSLRs are about to make a quantum leap in quality in the next year or so, and that I'll be better off waiting that much longer. Someone said that the rate of obsolescense has slowed down now, but I think there's still one more big step to be made before it plateaus for a while.

In that time, not only will we move on up the resolution side a bit more (I'd like to see 11 MP at a price around where the Canon EOS 300D is now), but we'll also finally put to rest the final advantages of film in terms of dynamic range, speed of focus, time between shots, etc. This is a really exciting time, because we're right there at the cusp. Digitial is already clearly better for low and mid range work and it can stand toe-to-toe with film at the high end. When those last few problems are solved, digital will be a clear winner for almost every application.

Neil Enns
03-02-2004, 06:48 PM
I'm just a lowly prosumer when it comes to photography, but I've shot both film and digital on Canon bodies. Each has their own perks, and I think the whole megapixel debate is silly.

I *love* the look of prints made from my Kodachrome slide film. Some of my favourite pictures of back home are taken on Kodachrome. I've never been able to come close to the colouring and texture (for lack of a better word) of the prints using digital.

At the same time I have three insanely pretty (IMHO) pictures of pointsettias on my wall that were taken on my Canon 10D at 100ISO and printed at Costco. Blown up to 12x18 they are indistinguishable to most people from similar shots I took last year on Velvia, and paid mucho $$$ to print on fancy paper.

Finally, Jason, I beg to differ on your comment about film grain. I've recently discovered the beauty of shooting at 800 ISO on my 10D. Sometimes the grain added gives a lovely additional something to the images.

David Prahl
03-02-2004, 07:23 PM
Check out his "Gigapixel" work:
http://www.tawbaware.com/maxlyons/gigapixel.htm

Suhit Gupta
03-02-2004, 08:28 PM
Time to break out the large format plotter and print that sucker 8O

Suhit

Jason Dunn
03-02-2004, 08:57 PM
I *love* the look of prints made from my Kodachrome slide film. Some of my favourite pictures of back home are taken on Kodachrome. I've never been able to come close to the colouring and texture (for lack of a better word) of the prints using digital.

Yes, I agree with you there - 35mm shots have a "texture" that's unique and hard to replicate with digital.

Finally, Jason, I beg to differ on your comment about film grain. I've recently discovered the beauty of shooting at 800 ISO on my 10D. Sometimes the grain added gives a lovely additional something to the images.

Fair enough. :) I haven't done much ISO experimentation with my 300D, so I don't have much of an opinion about this one yet.

Lee Yuan Sheng
03-02-2004, 09:05 PM
As Cocuta has said, there are way too many variables. For starters, the film camera was using consumer grade film. Try Reala 100 for print, or Velvia 50 for slides. There'll be a great improvement in grain and resolution.

Another point is that shooting newspapers and target charts is a fairly useless exercise. These are high contrast subjects, typically 1000:1 contrast ratio, vs the typical scene having a 6:1 ratio. Generally higher contrast will allow both sensor and film to give higher resolutions, since high contrast subjects allow for details to be picked up more easily.

Digital has progressed to the point where at higher ISOs (800 and above) digital performs incredibly well, even in mixed lighting conditions. And at lower resolutions using slide film, digital can hold its own against film. I've seen real life samples, shot on the same day, with similar camera and same lenses.

Did someone say film grain? *breaks out the TriX and Elitechrome 400*

Lee Yuan Sheng
03-02-2004, 09:11 PM
Geez, I saw MTF and I got turned off; I appreciate its usefulness, but obsessing over MTF (worse, MTF charts of lenses) is a poison many photographers tend to get themselves into. Don't. While it shows the contrast at a certain spatial frequency, it's typically done with a high contrast target, and may not be indicative of real world performance. Also there is a distinct difference between resolution and contrast; which is why lens manufacturers are willing to give up high resolution lenses for high contrast lenses.

Ok, I guess I kinda sidetracked, so I'll end it by saying; if a 35mm film user says digital is inferior, go take a Sinar and smack him on the head with it. :lol: If you find that too heavy take a Kodak 14n instead.

Gary Sheynkman
03-03-2004, 12:28 AM
Check out his "Gigapixel" work:
http://www.tawbaware.com/maxlyons/gigapixel.htm

Yeah that thing is huge:

Final image dimensions: 40,784 x 26,800 pixels
Number of pixels in final image: 1,093,011,200 (1.09 gigapixel)
Final image file format: RGB Tiff using deflate compression
Final image file size: 2,068,654,055 bytes
Number of source images: 196
Number of pixels in source images: 1,233,125,376 (196 images * 3072*2048)
Lens focal length: 280mm (equivalent to 450mm on a 35mm camera)
Aperture: F9. Shutter speed: 1/400
Number of control points in PTAssembler project: 779
Number of seams that were manually blended after stitching: 364
Horizontal field of view of final image: 63 degrees
Time required to capture component images: 13 minutes
Time required to set control points: 2 hours
Time required to optimize project: 2 days
Time required to stitch project: 4 days
Time required to blend seams / correct misalignments / finalize image: 3 days

I cant imagine that he did it on a
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What kind of supercomputer did you use?! Nothing too fancy. I used a generic PC with a (modest by today's standards) AMD Athlon 1800 processor and 1.5GB of RAM. The OS is Windows XP.
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backpackerx
03-03-2004, 12:40 AM
Check out his "Gigapixel" work:
http://www.tawbaware.com/maxlyons/gigapixel.htm
_________________
That is sooo sweet. Here I was impressed with my photostich software from canon. I have a nice 33 megapixel image of the panorama of my neighborhood :D

iand
03-09-2004, 03:46 PM
The debate of film vs. digital is completely different for professionals or even prosumers than it is for general consumers, and the problem is that the magazine or articles that debate it tend to do so from a prosumer and up perspective, while low-end consumers read it and take it as gospel.
Most of the film camerawork I see in real (read: everyday) life are pictures taken by people like my parents, friends, cousins, etc. They're pictures taken on cheap cameras developed at places like Walmart or Costco, and taken on low-end film purchased at those same places. So when those people ask me "are digital photos as good as film", the answer is almost always a resounding yes. Even the 2-megapixel photos I was taking 3 years ago generally made better 4x6 prints than most of what I saw coming such people on their film cameras.

Lotto
03-09-2004, 04:29 PM
LEO LAPORTE of TechTV fame was on Live with Regis and Kelly this morning. He happened to mention that film was roughly equivelant to 7 or 8 megapixels.