How can they print that big with only 12mp?

vitalsax · 03-06-2009, 06:32 AM

or how can they do it with 35mm?

whatch this: FiveFWD - Challenge - Blow Up - Part 3 video from The Gadget Show

ghelary · 03-06-2009, 06:50 AM

Simple the DPI is very low.

If you look at those print from a few feet away, you will wee a very low resolution.

A really good comparision would be made with the best finearts from the best printers / enlargers available.

Regards,
Guillaume

losecontrol · 03-06-2009, 07:10 AM

And still this shows why you don't need a 20mp camera. It's all about the distance.

maleek · 03-06-2009, 07:26 AM

Thanks for the clip. Interesting stuff!

Gooshin · 03-06-2009, 07:28 AM

1. film is only as good as the scanner used to digitize it

2. grain of ISO 400 on film is expected, noise on iso 400 digital is unwanted

3. film still has more DR, but why bother in a studio setting with a low DR setup?

4. thats one cool printer

5. we were never told what film was used in the F5

in conclusion, there is no conclusion, and i just wasted time watching that and typing this.

noblepa · 03-06-2009, 08:09 AM

Originally Posted by Gooshin

1. film is only as good as the scanner used to digitize it

IMHO, this is the fatal flaw in virtually every film-vs-digital comparison I've ever seen. Scanning the film turns the comparison from film-digital to scanner-vs-camera.

For a true comparison, you must use an optical enlarger on silver-based photographic paper. Granted, there are no enlargers big enough to make a print of the size in this video. Heck, there aren't many enlargers around any more, period. But, nevertheless, for a fair comparison of the two technologies, you must use each technology in the way it was designed. Film was designed and has a hundred years or more of development, using optical enlargers, not scanners.

A fair comparison might be 16 x 20 or 24 x 36 prints. Make the digital prints on the best printer you can find. Make the film prints with the best enlarger you can find. Then compare the two prints from normal viewing distances of a few feet. You could use a magnifier to examine the reproduction of fine detail or to look for grain/noise.

There is no denying the convenience of digital photography, and the quality of digital images has improved greatly, to the point that, for the average photographer (and many above-average ones, as well), there is little or no difference.

I find most film-vs-digital comparisons to be a waste of time. Either technology is capable of producing excellent results, far better than my ability as a photographer. Film has a different feel than digital. Some simply like using film more than digital. To each his/her own. But, like it or not, for most photographers, the future is digital.

GaryM · 03-06-2009, 12:36 PM

Originally Posted by losecontrol

And still this shows why you don't need a 20mp camera. It's all about the distance.

It depends on the application. If you've ever seen fine-art prints made from large format view cameras, you know the benefit of large amounts of fine detail. And those prints can really be stunning!

UnknownVT · 03-06-2009, 01:42 PM

Originally Posted by losecontrol

And still this shows why you don't need a 20mp camera. It's all about the distance.

It is true it is mostly about viewing distance.

With that size to see the full picture one could not view it from a few inches or even a few feet away - one really would have to stand back.

However with us photo nuts walking closer is likely to happen - again with that kind of size - the distance is going to much greater than a few feet or for a normal handheld size print.

There has been a long standing contention that says if one can print for the largest handheld print that can pass very close scruntiny - eg: nose to paper - then any larger print at correspondingly larger viewing distance will be fine -
so again it's the viewing distance.

The normal "correct" viewing distance is supposed to be equal to the diagonal of the print - and the closest optimal distance for the human eye is supposed to be about 25cm or 10 inches. That's why the long standing critical print size has been 10x8 (diagonal = 12.8")....
(EDIT to Add - actually strictly speaking a 10" diagonal print is 8x6 )

So the theory is that if one can print to 10x8 at critical "quality" - then anything larger will be OK (again caveat at normal viewing distances).

Of course again this breaks down if one goes very close to the print - (changes the viewing distance) - and for camera nuts - this may not be adequate...... but for most people this is OK.

200ppi has been held as a mark of quality for digital prints - so a 10x8 is a mere 2000x1600 pixels = 3Mp - that maybe why Canon produced their first dSLR at 3Mp level the Canon EOS D30 (not to be confused with the 30D).....

However these days with more Mp this printing density has raised to 300ppi - which is close to the critical 6lp/mm print resolution (= 305 ppi) especially for smaller prints like 6x4 or 7x5 -
if one extends this 300ppi to 10x8 - then that's 3000 x 2400 ....
hello 6Mp (OK not quite, but close enough for jazz....)
That is why the rush of dSLRs was when it reached 6Mp
(eg: first Canon Digital Rebel)
(EDIT to Add - actually strictly speaking since a 10" diagonal print is 8x6 that pixel count at 300ppi is only 4.32Mp!!!)

So "in theory" anything 6Mp and above should be able to handle almost "any amount" of enlargement - as that 12mp enlargement demonstrated (17 x10 metres) -
worst case 6Mp should be able to get the same quality for half that size (10x 8.5 metres) right? -
I would hazard to guess that most of us would be quite happy with that.....

*RuiC* · 03-06-2009, 03:30 PM

Originally Posted by Gooshin

1. film is only as good as the scanner used to digitize it

2. grain of ISO 400 on film is expected, noise on iso 400 digital is unwanted

3. film still has more DR, but why bother in a studio setting with a low DR setup?

4. thats one cool printer

5. we were never told what film was used in the F5

in conclusion, there is no conclusion, and i just wasted time watching that and typing this.

In my purely amateur opinion, only a fool would print that large from ISO400 film. I would use ISO50 or 100 max.

RuiC

UnknownVT · 03-07-2009, 11:49 AM

Originally Posted by RuiC

In my purely amateur opinion, only a fool would print that large from ISO400 film. I would use ISO50 or 100 max.

This is true - but the difference may not be quite as wide as one might imagine.

I used to "study"/scrutinize color print film articles comparing films in Photographic and Popular Photography magazines as well as the sterling work in the Film Characteristics Table

Here's one of the "best" 100 color print films - specs from manufacturer comments by Photographic Magazine -

compare to a 400 film (look at the specs) -

the spec'd grain size (RMS value) and the resolution are almost same!

To be fair in the Film Characteristics Table:
which is "Sorted by grain, then resolution, then sharpness."
Top of the table were:

further down were the 400 group -

even so this shows that although there is obviously a difference between the best of the slower speed films and 400 film - it is not a gulf of a difference.

But I would agree that in principle for that kind of enlargement I would have chosen a film from the top of the group, as opposed to a 400 film.

But to be fair to the TV program - they were comparing the dSLR (Nikon D700) at ISO400 so had to use a "like" 400 film.

They probably should have compared at ISO100 to be able to see the full potential of modern film -
although the call might have been closer -
I doubt if it would have affected the outcome that much.

Sodbuster · 03-07-2009, 05:18 PM

Or the angle the image subtends to your eye.

*Jonson PL* · 04-05-2009, 02:21 PM

Originally Posted by vitalsax

or how can they do it with 35mm?

whatch this: FiveFWD - Challenge - Blow Up - Part 3 video from The Gadget Show

If you stand really close to commercial prints, larger than life size, then often they are less impressive. Viewing distance matter.

Thanks for the link. Though for 35 mm film to show its best, you don't use Iso 400. Iso 25, 50, 64; preferably below Iso 100.
We don’t know if the film shots were drumscanned. And whether they were from slides or negative.

But I’ve never seen such a big enlargement.

This is the place that did the printing :
Canvas Prints ,Picture frames, Photographic Prints, Wooden Canvas frames

stevebrot · 04-05-2009, 03:25 PM

Originally Posted by noblepa

...For a true comparison, you must use an optical enlarger on silver-based photographic paper. Granted, there are no enlargers big enough to make a print of the size in this video. Heck, there aren't many enlargers around any more, period. But, nevertheless, for a fair comparison of the two technologies, you must use each technology in the way it was designed. Film was designed and has a hundred years or more of development, using optical enlargers, not scanners...

You are so correct. However, I can point out that my enlarger is quite capable of projecting an image that size except that media and processing might be a problem. (Many enlargers can swing to project horizontally, mine included...)

I agree with the other comments regarding the use of ISO 400 film. Even with an 8"x10" enlargement the grain would compromise the image quality relative to the same picture taken with a D700 at ISO 400.

So, what I take away from the video is that at ISO 400, there are certain advantages to using a D700! If you need higher ISO and high resolution, FF digital is the way to go. (I can feel the flames now...) On the other hand...I judged the skin tones and tonal gradients to be much more pleasing and true to the subject on the film image and had judged the left image to be film on that basis before they even showed the lower resolution of the shoes.

Steve

SpecialK · 04-05-2009, 03:34 PM

The normal "correct" viewing distance is supposed to be equal to the diagonal of the print ...

I learned it as "lens focal length x degree of enlargement".

*chalion* · 04-05-2009, 06:35 PM

When I looked at those 2 prints when both hosts and those prints were near the same effective size, that's when I chose which print was film and digital (I did pick them out correctly too).

I agree with noblepa. This is not a fair comparison between film and digital; these are media for 2 different eras. (I don't mean eras, here, but I cannot think propperly at the moment).

I'd be more impressed if the digital were converted to slide format then projected BACK into digital, while the film was developed into slide format then converted to digital. (But then if both were viewed on a digital screen, people would have problems with viewing film shots on a digital format).

Both film and digital have their places and really shouldn't be compared against each other.

The only real difference to me, in my opinion, is that digital gives the average photographer the ability to play with their photos to make look how they want them before printing them out (which some nicer printers can make look as good or better than if they took them to someone to get developed into print).

Lastly................i'd really hate to have to have paid for those huge prints! The paper(canvas, whatever) cost alone would be staggering.