Grossly Oversimplified

Bill Pierce

Bill Pierce

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Erwin Puts has pointed out that you should shoot film tests to properly test a lens, especially lenses of high quality.

I hope I am not misrepresenting what he is saying, but slow, specialized films can capture higher resolutions than, for example, the M8 sensor.

On the other hand, there is a great deal of talk that digital images from cameras with moderate sized sensors are delivering results better results than film, results that we might associate with medium format. Are these two thoughts at war with each other?

My guess is that most 35-mm film photography is not done with slow films, but films like Tri-X or similar speed color negative films. I suspect it is also done handheld and without bracketing focus. In other words, we don't use cameras, digital or film, in a way that preserves the ability of the finest lenses to preserve their high resolution capabilities.

However, the ability to manipulate "sharpness" in digital images let's us take that mid-level resolution that many of our cameras deliver without a strain and enhance it. In other words, both camps are right. Film can deliver higher resolutions than sensors, but in typical day-to-day shooting digital may look "sharper."

This may take the cake for gross oversimplification of a complex subject. But in day to day work my M8 is sharper than my M3 (but my M3 is much more loved and a member of the family). And my Canon 5D Mark II, even with its full strenth anti-aliasing, is sharper than my M8 probably because I can take advantage of high ISO's without putting image quality in the toilet.

Many folks here shoot digital and film. I'd love to hear some grossly oversimplified remarks on the subject from them, too.

Bill
 
Puts also says that although film delivers higher resolution, the subsequent links in the processing chain -- enlarging or scanning -- reduce that resolution. Therefore, in practice the higher resolution of film isn't realized even if slow speed film and tripods are used.

Fortunately resolution isn't everything. For example: I understand the tonal range of well-developed BW film is still beyond what in-camera sensors can deliver. Do I understand correctly? And no digital camera delivers what Kodachrome or Velvia does, to name just two colour films.
 
The comparisons of full frame 35mm digital to medium format film usually talk about enlargement capability.
Medium format still has different tonality and depth of field characteristics.
It's also now way cheaper to shoot MF film than full frame 35mm digital!
 
photogdave said:
The comparisons of full frame 35mm digital to medium format film usually talk about enlargement capability.
Medium format still has different tonality and depth of field characteristics.
It's also now way cheaper to shoot MF film than full frame 35mm digital!
Click to expand...

Amen to that. High end digital photography is the only thing in the photographic world that can make shooting with a 4x5 view camera seem cheap.
 
I think Ken Rockwell was right when he said that 35mm film (velvia) resolves just under what a 25MP full frame DSLR will do. His tests seemed to prove that. Scroll down to the 6th picture in this link and you will see. The pictures are rated in order of sharpness from top to bottom: http://www.kenrockwell.com/nikon/d3x/sharpness-comparison.htm

Having said that, it is a lot cheap for me to use my old Contax 167MT loaded with Velvia and getting it processed, mounted and scanned than buying a new Canon 5D Mark II for what I shoot.

For the price of a Canon 5D MII body, I can buy a Contax G2 system with 28, 45, 90, a new Nikon supercoolscan 5000 and still have money $400 left over for for Velvia and processing. The amount I shoot, this would last me well over a year. And I am sure that the quality difference would not be all too noticeable.

Having said that, I do have a DLSR (a Rebel XTI) that I bought used. It is a good tool for low light color photography - good enough for me.

I think this is also a good layman's summary: http://www.kenrockwell.com/tech/film-resolution.htm
 
Bill Pierce said:
Erwin Puts has pointed out that you should shoot film tests to properly test a lens, especially lenses of high quality.

I hope I am not misrepresenting what he is saying, but slow, specialized films can capture higher resolutions than, for example, the M8 sensor.


Many folks here shoot digital and film. I'd love to hear some grossly oversimplified remarks on the subject from them, too.

Bill
Click to expand...


1. Film out-resolves digital.
2. Digital out-resolves lenses, so I've heard.
3. Film therefore is superfluous.
3. Might as well just take advantage of digital's convenience.
 
If I do my job, it really is hard to guess which image is which, in my experience. I do know my slides-35mm or 6x6-look better on a light table than any image on a computer screen, or on paper, regardless of whether it started as film or digital.

Resolution just isn't that important after a point. Since my images look fine either way (and if I shoot TriX, I expect it to look like TriX), my only real choices are the camera and the medium, and so far I prefer my images on film.
 
I shoot b&w film and digital- but my 'workflow' is completely digital as I scan my negs (6x4.5 and 35mm) on an Epson v700. I know! Bad boy! Not the best way to do it, but for my purposes (I don't print in a serious way- Costco $1.39 8x10!) it is perfect. My digital camera is a humble Pentax 200d with the Pentax 35mm 2.8. If we are pixel peeping (300% crops) then the Pentax blows my film work away in terms of sharpness and resolution! But the way I do things isn't professional by any stretch. I prefer to use film cameras and all the glorious varieties they come in (cheap!). If you want full frame digital it will cost you an arm and a leg. My Olympus XA is also full fame... you get the point.

I recently had some 11x14 done up at Costco from a couple of 6x4.5 negs that I developed and scanned and my wife thought they looked fantastic.

Who is your audience? Do they care what sort of camera you used? Maybe...
 
In my experience, Nikonscanning @4000ppi is grain-sharper than anything possible with an enlarger (including point source, which I've done). As well, it's even more subtle than optical enlargement, B&W or color. This does, however, assume a good printer (Epson 2200 or better in color, QTR driver in B&W or more recent K3 Epson printer). Some of the current inkjet papers give astounding blacks (Moab Colorado Satine, for example).

DSLR (Pentax K20D) is higher resolution, without doubt, than 35mm scanned film...it's obvious in pores of portrait subjects. On the other hand, the lower detail resolution of film and especially of some film lenses can be attractive.
 
You are spot on Bill. On a recent trip to Myanmar I took my Leica M6 with Tri-X and my new 5D Mk 2 with manual prime lenses. I am very happy with the results form both, which are very different indeed, and even happier to have used both and not just tried to find that mystical one camera/format for all purposes.
 
Puts is using Tmax 100 and Delta 100 in this text, so it is not very "specialized" I think.

Film might have more grain, but it still has more resolution in fine details than digital.

Sharpening does NOT give any more information, but may bring it up so it is easier to observe.

(Normal, 35mm or smaller) digital cameras dont compare to medium format in resolution when talking about details. Maybe in graininess and pixels they do, but that is not resolution.

MTF or modulation transfer function consists or includes all the imaging factors, including the lens, the sensor etc... So if we are measuring a lens, we should have all other factors as close perfect as possible. Digital camera will lose more resolution than film because of the bayer mask and antialias filter (which I guess M8 doesn't have though), so film is better for MTF measurements.

You might be interested:
http://www.normankoren.com/Tutorials/MTF.html
 
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Over simplification wanted? Okay! Here's my rule of thumb for film to digital equivalence.

Just presume that a film system can safely resolve 40-50 lp/mm.
Picking the arbitrary value of 50 lp/mm, we have the following.

135 = 2400x3600 = 8.2mp
645 = 5600x4000 = 21.3mp
6x6 = 5600x5600 = 29.9mp
6x7 = 5600x6800 = 36.3mp
4x5 = 9500x12000 = 108.7mp

I find this equivalence useful for what I do and it matches empirically with my experience. Basically, my Rebel Xt about matches 135 film and my 5D kicks 135's behind. I scan at 4000dpi which gives me a very nice look at the film grain. However, I don't consider all 4000dpi to be printable.

Since it is common practice to print at 300 dpi for optimum viewing at 10" for 135 film, this table works out a maximum 8x enlargement. If I'm only really getting 40 lp/mm, 240 dpi happens to print nearly indistinguishably as nice.

What a coincidence! 8x was a decades-old rule of thumb used for enlarging 135.

If I got all the 2400x3600, I might squeak out an 11"x14". Just like back in the day.

But now if my technique gets almost the full 2900 on the short-side with the 5D, I'm comfortable about cropping even for an 11"x14". Or maybe even squeak-out a 16"x20" if I don't need much of a crop.

And if I know I need to go big and I have the time, I'll bring out the 4x5 or the Nodal Ninja and bring home all the pixels.

Some say they can get better and maybe they do. It doesn't bother me.
 
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Thanks, for posting this, it is interesting to see the responses. Like everybody I have and use both technologies. And as for resolution is not important to me. I use my many different cameras and lenses for specific purposes that are geared to the lens or camera. And when I combine all the great films available; the permeations of special combinations makes my photographic life just great.
 
They're different.

I have a 5D (mk 1) print at 18 by 12 here that shows the resolution difference very clearly. there is fine detail rendered with good contrast, compared to 35mm film where the contrast falls earlier and then grain starts to obscure the image information. Looking at a print I like both, so that's fine.

If you consider the MTF of film and compare it the MTF of a sensor you typically see a much smoother decline in the MTF of film than digital sensors which maintain a high MTF until they sharply cut off (anti alias filter helping here). Effectively, although some 35mm may have more resolution thana 12+Mp digi snesor, this is usually at a lower MTF and so digital prints look sharper and more detailed. Further, noise is not an issue in low iso digital prints and grain is, so the grain impacts on enlargability too.

I wondered how close Ektar 100 would get to a 21Mp digital capture and the answer it doesn't, but that's not a problem as it does other things well.

The comments about digital not giving colour like Velvia (which I'm not convinced really resolves equivalent to 25Mp...) is not really relevant as the sensor simply records a set of numbers. These can be interpreted to give colour like al sorts films, or diferent if you like. Clearly the photomags and flickr are full of over-saturated images, so the Velvia look lives on🙂

Mike
 
Your thesis may be grossly oversimplified but as far as I'm concerned it's quite accurate. I do photography, not photographic testing. I do books and exhibits and I have found your "oversimplification" to be basically true. Even stuff I shot years ago with my D70 makes stunning, very sharp, very big enlargements. Alien Skin plus just the right amount of sharpening can deliver natural and absolutely stunning results. I also love Tri-X. My latest book was shot exclusively on Tri-X and HP5+ and printed in the darkroom. My latest exhibit was shot with DSLR's from the D70 to the D300. These processes are what they are, it's all in what you do with them. But damn those big blow ups from the DSLR's are sharp as sin. And the big blow ups I do in my darkroom from Tri-x are full of great detail and lush grain. It's all good.
 
I found the original post easy to understand and logical. Good question, and salient observations, I think 🙂 I agree with Mr. Puts on this, as I understand where he is coming from, I think (based on my understanding of his work, not having seen this particular test).

Doesn't anyone think it's important to remember that film doesn't break a scene down into squares? A diagonal line on film is a diagonal line, while to a digital sensor it is a stairway. Talk resolution all you want, but at the end of the day, a digital shot is interpolation of multiple sensor pixels for each image pixel. Film shows pretty much the light that hit it at that spot. Current film technology is the only limiting factor to accuracy. And the fact that anyone would suggest their top-of-the-line digital somehow beats it is proof that film is universally seen as the end-all be-all of the art/science.

If you set aside resolution as a mere counting of lines and approach it as accuracy to the image coming through the lens, there is no contest. Film by nature dominates. Digital is like looking through a screen compared to film. The fact that the screen is photoshopped out of the scene doesn't change the fact that it was there during the capture.

And IMHO, to compare digital and film one has to print each and compare the prints. At the end of the day, digital images are either reduced to fit on a typical monitor or printed via dots of ink on paper. A film image is projected on paper and no math operations are performed between negative and paper and it's not tied to the limited resolution of the printer or the limited gamut of the inks.

It's really kind of interesting to me how many people ignore the fact that all internet film vs. digital tests are comparing scans to captures as if there is no difference between the film and the scan.

Last night I developed and scanned a roll of film. Today I took the scans to Walgreens and Ritz Camera for 5x7 prints. Upon comparison, the Walgreens prints from the kiosk are superior to the Ritz prints from their kiosk. The source digital image was irrelevant to the output as the printer and paper was the deciding factor. In the next week I will be making wet prints of the same shots for comparison purposes, and there is no doubt (from past experience) that even my laziest effort will result in a superior print from a nerdy "resolution" point. The effort it takes to get the "perfect" print is subject to personal skill/experience regardless of medium.

Why don't people who insist on comparing digital captures to film scans compare scans of prints from each? To me that would be the only way to convey - with images over the internet - which is better from a quality perspective.

It should be obvious, but captures from a 25MP DSLR are overkill for sharing on Flickr. Most film is overkill. Your basic 110 Instamatic *theoretically* would be more than adequate 🙂

I appreciate the film vs. digital debate (in whatever guise) because it forces me to consider my position based on facts. I think I am a better photographer because I am aware of multiple issues that impact the final output.
 
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Bill Pierce said:
Many folks here shoot digital and film. I'd love to hear some grossly oversimplified remarks on the subject from them, too.

Bill
Click to expand...

slides, chromes still have better resolution than digital.
i like digital otoh an image is more than "quality".. there is a personality, a signature w/ each proccess, each camera and lens you use.
i have been shooting digital too long and began missing film's "defects": grain mostly. and format. i wnat the big 120 film canvas.
i am still not excited about developing film, contact shhets and going back and forth to labs.
 
No, film breaks the image down not into perfect little squares but into clumps of grain. The continuous tone of both is an illusion. Just blow a 35mm negative up large enough if you don't believe that. The millions of little squares result in a cleaner image than the little clumps of grain. It ain't rocket science.
 
Pickett Wilson said:
No, film breaks the image down not into perfect little squares but into clumps of grain. The continuous tone of both is an illusion. Just blow a 35mm negative up large enough if you don't believe that. The millions of little squares result in a cleaner image than the little clumps of grain. It ain't rocket science.
Click to expand...

Buy a microscope. Draw what you see as little squares of a single color on graph paper. Now tell me that is more honest to what you really saw than a colored pencil sketch.
 
Pablito said:
Your thesis may be grossly oversimplified but as far as I'm concerned it's quite accurate. I do photography, not photographic testing. I do books and exhibits and I have found your "oversimplification" to be basically true. Even stuff I shot years ago with my D70 makes stunning, very sharp, very big enlargements. Alien Skin plus just the right amount of sharpening can deliver natural and absolutely stunning results. I also love Tri-X. My latest book was shot exclusively on Tri-X and HP5+ and printed in the darkroom. My latest exhibit was shot with DSLR's from the D70 to the D300. These processes are what they are, it's all in what you do with them. But damn those big blow ups from the DSLR's are sharp as sin. And the big blow ups I do in my darkroom from Tri-x are full of great detail and lush grain. It's all good.
Click to expand...

Haha, I love it!
 
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