Does larger digital file = greater amount of useful data???

[bill_glickman]

There has been much discussion on this forum for Digital vs. film. Below is a link to a very reputable site which compares the new Canon D30 digital camera with Provia F film.

 

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http://www.luminous-landscape.com/d30_vs_film.htm

 

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I was amazed at what I read, and now am re thinking how digital my impact our future. The part of this review, (and others on the same product) is the file size comparison. For example, a Canon shot taken with the D30 produced a 9 MB file, however the same shot taken with Provia F and scanned at 4000 dpi on a Imacon scanner produced a file size of 34 MB. Conventional wisdom would tell us the scanned file with almost 4x more data would be noticeably sharper. However, all the test I read so far revealed the same thing, both prints were equally as sharp!! Or if anything the one taken with the digital camera were even sharper?

 

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So the looming question on everyones mind now is... does larger files necessarily equate to more useful information for producing higher quality prints? Why do these film scanned files contain so much extra data - but does not seem to translate this data to the actual printed photograph?

 

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Considering the price of this technology, about $3k usa for the D30 camera, it may not be long till digital moves faster than we all thought into larger formats. This assumes the relationship between file size (or image capture size) is not the benchmark of quality we all once thought. Any ideas of why the scanned film files are so much larger but do not provide a superior end product that one would suspect?

 

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In this test, the smaller D30 file was ressed up using software (G Fractols I think) to match the size of scanned file...however, I am doubting that is the missing link, if so, who needs LF files to begin with if we can just ress up smaller digital files.

[richard_ross]

I think it is a given that leading edge digital image capture is

already very close to 35mm film. CCDs are slowly giving way to Si

based photodetectors (CMOS technology) as demonstrated by

Foveon (http://www.foveon.net/) who have a square 16Mpixel device

available. You of course pay the price in storage and energy

requirements. It will be a while before these devices become available

in larger formats but it will happen. It will probably be

longer, however, before the storage and power requirements are brought

under control with dense magnetic RAM (or some comparable technology)

that can replace disc drives and operate on a few AA's.

 

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As for "ressing up smaller digital files", which I assume means some

kind of interpolation (?), forget it. You don't get more resolution

this way, you just get bigger mushier images.

 

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For LF field photographers, digital is quite far away. Not so far for

studio though. Lets just hope the film companies don't quit too early!

[larry_huppert1]

I believe the pro one shot backs (e.g. Phase One) have image sensors

the size of 35mm film currently. I've seen some stunning 16x20

prints from 16 Mpixel one shot captures. Even with this smallish

capture area, I've seen a pro mount a Phase One on a 6x9 view camera

and do product shots. He owns a scanning back, but is finding that

16 Mpixels does the job most of the time.

 

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I would contend that digital capture is absolutely here for much

studio based work. For that matter, I know several local pros who

travel with their digital rig on location. They setup their computer

on a cart, and do their work. They are getting new clients because

they are all digital. By being rigorously color managed, they have

more control of their image all the way to press. For small prints

(up to 8x10) they are using some local minilabs who have digital

front ends (e.g. Fuji Frontier). They will typically build color

profiles for these minilabs. Many of these commercial clients only

want digital files as the end product anyway. The big problem is

that it's a significant capital outlay (or lease expense) at this

point. Makes it tough for the person getting started in business.

[qtluong]

A first explanation would be that in spite of his claims, there

is somewhere a weaker link in the chain leading to the print.

I'm sure that someone could argue that with a 100M scan on a Tango

and a lightjet output, differences might become visible.

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A second explanation of the paradox might be that a lot of image

information is redundant. Somehow this information is reconstructed

adequately from the smaller file by software. Think about a photograph

of a flat dark square against a light background. All you need to do

to obtain a hi-res image from a small file would be to do some kind

of smoothing of the edge.

[pete_andrews]

I've said it before, and I'll repeat it now.<br>Comparing the grain

image of film with a pixel image is like comparing apples with

bananas.<br>A film grain image is actually more digital in nature than

a pixel. Grain, and/or colour film dye, is either 'on' (developed), or

'off'. There are no in betweeny colours with film; they must be made

up from aggregations of silver or dye speckles.<br>Now, even an 8 bit

pixel can have 255 different levels of grey, or 16.7 million colours

with 24 bits. So a given area of film must contain 255 'grains' to

represent the same range of tonal values as an area of 1 pixel.<br>If

you do some real measurements of film grain or dye cloud size, and

compare those with current pixel sizes, it turns out that a pixel size

of 5 microns, (such as is common in consumer digicams) has a greater

image capacity per unit area than all but the finest grain films on

the market.<br>All that needs to be done is to make larger area

CCD sensors.<p>If you extend that to current state-of-the-art sensors,

then area for area, CCD or CMOS devices are capable of <i>better</i>

image quality than commercially available film.<br>Why do you think

that most astronomers now have CCD sensors strapped to their

telescopes, and not film cameras?

[josh_slocum]

Pete:

You forget that those "255 grains" that film "must have" to equate a

pixel are usually considerably smaller than the pixel. That is why

film is, often, (not in all cases), more continuous tone in nature

than digital. High end cameras not withstanding- and I'm sorry, but I

don't think even 16 mp is going to make me give up Kodachrome 25 or my

medium/large format gear- digital just doesn't cut the mustard for me.

Please don't accuse me of not knowing my facts- I've seen the digital

prints from the D1, the Kodak 6mps and Michael's Luminous Landscape

page. Strangely, the Provia images still look sharper to me.

The bottom line, I guess (and I'm guilty of this too) is that we can

argue equipment all we want, but the results count. Having said that,

I HAVE YET to see someone show me a digital pic that I cannot match or

exceed in resolution or tonal quality with any of my film gear. It's

true, digital is a lot closer to 35mm than it used to be, and in high

end cases can exceed it, but 35mm is damned good stuff. . people seem

to forget that, even though last year they were selling their prints

like hotcakes to satisfied customers.

 

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Larry:

One question. . why are all these pros "getting more customer because

they're completely digital?" Don't tell me it's because clients truly

understand the image process-if they did, they'd know that any medium

or large format image would exceed their quality standards anyway. I'm

almost positive it's because of the magical aura around the "D" word,

and has no basis in real understanding of the photographic process. If

they did understand it, they'd know it was possible to A) shoot the

highest quality film images. B) Make top notch optical prints capable

of satisfying the most crucial assignments (it's been done for more

than 100 years before digital) C) Develop and scan the film in under

an hour, thereby negating the argument that only digital cameras can

deliver electronic files.

You see what I mean? How many clients, except for the NY TIMES,

absolutely must have the finished image immediately and cannot afford

one hour's processing time???

 

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I guess it's my basic loathing of the fact that clients are so

uninformed and so easily marketed by hype that separates me from the

"pros."

[larry_huppert1]

Josh,

 

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I'm not shooting digital (yet), so I can only give you the info as I

understand it from some who are shooting this way. One question - if

the client is going to press, and needs a quality digital file as

part of this process, how is it advantageous to shoot film as an

intermediate step (assuming your shooting something where digital is

an appropriate tool)? It does provide a tangable reference to the

customer, but that is far from the end product being the image in

print.

 

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Control (and revenue) of a greater chunk of the process seems to be

the first advantage. From what I've seen from these folks, the RGB

to CMYK conversion is non-trivial. It appears to be one of the

causes for "good" transparencies to print poorly. By being involved

from capture to print, the photographer can assure the integrity of

their image. These photographers will color profile the printing

press being used, on paper stock being specified and target a RGB to

CMYK conversion which will yield the best results. The client

probably likes the fact that photographs are printing more

realistically, and that one person is taking responsibility for that

result. That service is of great value to the customer, and they are

willing to pay for it. I've also heard that clients like seeing the

results immediately on the screen during the shoot. MUCH better than

any Polaroid could ever show. Small tweeks can be made in real time.

 

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Shooting film and scanning are also important parts of being

digital. As has been mentioned by others, digital capture has a set

of limitations where film is often the better choice. However, as a

process, I don't understand where your coming from. Quality film

scanning is more expensive in time and money than quality digital

capture.

 

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Regarding the time equation... The best E-6 labs in this area can get

the film back in about 2 hrs with a rush charge. Normal turnaround

is closer to 3 to 4 hours. Where do you get 1 hr E-6? Professional

C-41 processing seems to take even longer than E-6 (except at

minilabs). I've yet to hear of anyone who prefers scanning negs

rather than chromes anyway. Professional scanning services are also

on a day or two turn around (without rush charges). I believe these

clients are often under strict deadlines, so the extra couple days

for shooting film + scanning is real money to these folks. The other

interesting thing I've observed is that some of the early pro

adopters seem to be extremely fine photographers who are located in

relatively remote areas. For these folks, the closest professional E-

6 lab might be 2 or 3 hours away. From a practical standpoint, they

overnight mail their jobs, so on just film, they are really 2 days

for first results. If holdback sheets need to be processed, the

first good film might be 4 or 5 days from the shoot. Digital

shooting seems to be a big win for these people.

[alpshiker]

"Any ideas of why the scanned film files are so much larger but do not provide a superior end product that one

would suspect? "

 

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Bill, I don't understand. A digital picture is a mosaic of pixels. If you have a mosaic with 400 and the same with

1600 pieces, and you look at them from a distance, they may appear just the same. But when you walk closer

you will soon realize one contains many more elements than the other. Similarly the 9 and 34 MB images may

look alike when printed at a size of 8x10", but if you enlarge at say 12x16", there should be a difference, at

least this is what I think. I have read good reports on Genuine Fractals software capability of upsizing an image

(and downsizing as well). However I doubt it can transform a 35 mm image into a high definition 4x5 image. To

continue with the mosaic comparison, it would be like a mere guess reconstitution of a damaged mosaic where

parts were missing, compared to the original artist work.

 

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Or shall I sell my LF gear before it's value drops and get the D30? Of course I'm kidding.

[pete_andrews]

Josh. The problem is that film grains aren't <i>considerably</i>

smaller than a pixel.<br>I've recently had cause to measure the 'dye

clouds' of colour film, sad man that I am, and even the finest came

out at around a micron diameter. Now even if these clods of dye were

laid out in an orderly manner (which they ain't), there would still

only be 25 of them in the same area as a consumer digicam pixel. Well,

OK; there'd be 75 in the depth of the CMY layers, that's still a few

short of the 765 grains needed to emulate the colour depth of the

pixel.<br>Think about it, a consumer digital camera has a sensor size

of about 6mm x 8mm. What sort of quality can you get from an area of

film that small?

[paul_rentz]

There is a point of "no greater return" because the device printing

the image doesn't output more "information" than a certain amount-

feed it more and it just throughs it out. Sometimes it just makes it

worse. Yes, the larger you print, the more information is needed.

[dan_smith]

How do the comparisons look on something like a 20x24 Ilfochrome

print? Or on a Fuji Supergloss print of that size?

I am sure digital will continue to get better and pixelographers will

be coming out of the woodwork luring hot babes into taking their

clothes off to model for these guys... some things will never change.

Mediocre images will still be mediocre images whether taken with a

pixelrecording device or an 8x10 view camera.

For now we know silver based negs will last and silver based prints

will last & many alt process prints will last. We **think**, based on

best guesstimates & accelerated image tests, that pixelography images

will also last. But, just as the odd fading with Epson prints

suddenly showed up & Ozone was the culprit, who is to say that the

pixelographer covering the nude jello wrestlers won't find his images

disappearing before his eyes due to the electrical field of the

interaction with buttcrack sweat & the green dye in the jell-0?

Digital stuff has a bright future but for now it is a "just as good

as" game. Given the choice, I like the original better. When "just as

good as" goes away & pixelography becomes its own medium and quits

trying to be just a copy of what we already have I will be much more

excited by it. After all, Madonna is "just as good as" Marilyn, but

having seen Marilyn I will keep her memory rather than the imitation

available now.