Medium format versus digital sharpness

"Matthew Winn" <*@matthewwinn.me.urk> wrote:

> If you're photographing a subject with low contrast,
> then once you've taken the lens into account the detail that might
> be retained by the film at 100 lp/mm is getting lost in the noise.

If you are photographing a subject with low contrast (as most of us are:
there are very few things in real life that have the 1000:1 contast of
resolution test charts) the MTF performance will be very very different from
the published graphs, which only apply to 1000:1 contrast patterns. TMX100
resolves 200 lp/mm at 1000:1 contrast and 63 lp/mm at 1:1.6 contrast.
(Classic Velvia claims 80 lp/mm at 1:1.6 and 160 lp/mm at 1000:1, but it's
large MTF gain at 10 lp/mm is more likely why people love it than the high
end of the performance. This is a cheap shot at Velvia fans, but I actually
think that it's right. And it's the reason you really want to use Velvia50
at f/45 and f/64.)

There are very few films that can resolve much over 60 lp/mm at low
contrast.

To the best I can tell, lp/mm at 1000:1 is a lousy measure of performance
_for photographic purposes_. Even the 1:1.6 figures overstate the
capabilities of film, since that's for a low response that's not
photographically useful.

>> And laying that much down on film is not a tall order for even quite
>> 'average' lenses either.
>>
>> But that doesn't suit the how-good-digital-capture-is camp at all.
>> So they forget about the soft focus filters that are in front of their
>> sensors. they forget about the small size of their sensors, and still
>> think
>> that because the file that comes out at the end contains so many pixels,
>> it
>> must be very good.
>
> I am wondering how much the theoretical performance of the latest high
> resolution sensors is compromised by the capabilities of the lens.

The 5D has a Nyquist frequency of 60 lp/mm, and it's not all that hard to
provide decent contrast at 45 to 50 lp/mm. Images look great at f/16, maybe
a tad softer at f/22.

That's plenty to create significantly better looking images than 35mm film
can even dream of. If you take your eye off the test charts under your
microscope and actually look at some prints. (Cheapshot a QG, not you.)

The D2x (Nyquist frequency more like 90 lp/mm) fans _claim_ that they get
sharp images near wide open with their fast lenses, but I'd like to see a
careful comparison at similar f stop. However, the D2x has an even weaker AA
filter than the 5D, and I've seen aliasing in real-world D2x shots, so they
are getting over 90 lp/mm images at the sensor. Some of the time, at least.

David J. Littleboy
Tokyo, Japan
 >> Stay informed about: Medium format versus digital sharpness 

Michael Benveniste wrote:

> I'm afraid that's not correct. In order to count line pairs, one has to
> make an assumption about how much of a difference between "dark grey" and
> "light grey" counts as distinguishable.

Yeah right...
A visual medium. A visual and visible phenomenon.
And we need assumptions to tell us when we do or do not see something...

You do not see the immense absurdity of what you are proposing? I do!

>>> I can assume [...]
>>
>> Indeed!
>>
>
> Quite a refutation. I guess I assume physics is valid.

Perhaps you do. Perhaps you don't.
And if you like we can start a epistemological discussion about "physics",
the way people understand their environment.

But whether we do or not: here, you are discussing not the matter in hand,
but indeed your assumptions.
 >> Stay informed about: Medium format versus digital sharpness 

On Mon, 8 Oct 2007 20:28:39 +0200, "Q.G. de Bakker" <qnu.RemoveThis@tiscali.nl>
wrote:

>A visual medium. A visual and visible phenomenon.
>And we need assumptions to tell us when we do or do not see something...
>
>You do not see the immense absurdity of what you are proposing? I do!

Well, I see the immense absurdity of claiming that a image with a total
contrast difference of 2% is a photograph. If that's what you're
looking for from film, enjoy your 140 lp/mm of barely perceptible shades
of gray.

>Perhaps you do. Perhaps you don't.
>And if you like we can start a epistemological discussion about "physics",
>the way people understand their environment.
>
>But whether we do or not: here, you are discussing not the matter in hand,
>but indeed your assumptions.

When you stop playing semantic games and try to refute my evidence that
scanners cause resolution losses, I'll be here.

--
Michael Benveniste -- mhb-offer.RemoveThis@clearether.com
Spam and UCE professionally evaluated for $419. Use this email
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 >> Stay informed about: Medium format versus digital sharpness 

Michael Benveniste wrote:

>>You do not see the immense absurdity of what you are proposing? I do!
>
> Well, I see the immense absurdity of claiming that a image with a total
> contrast difference of 2% is a photograph. If that's what you're
> looking for from film, enjoy your 140 lp/mm of barely perceptible shades
> of gray.

But you still don't see that you are discussing your assumption, not the
matter in hand.
What "image with a total contrast difference of 2%"?

> When you stop playing semantic games and try to refute my evidence that
> scanners cause resolution losses, I'll be here.

What "evidence"?
And the "game" is your attempt to claim that scanners lower resolution
enough so that the resolution they produce can not be the resolution they
produce.
As nonsensical as asserting that we need calculations to tell us what we are
seeing.
 >> Stay informed about: Medium format versus digital sharpness 

On Mon, 8 Oct 2007 16:41:16 +0200, "Q.G. de Bakker" <qnu DeleteThis @tiscali.nl>
wrote:

> And there's a "third" too:
> Why are you looking for "consumer" grade film to compare digital to?

Because I originally responded to Ken Hart, who said:

"A source that I trust (but no longer remember who!) claims that
36Mpixels equals average consumer 35mm film."

When I scan 35mm consumer films from about a decade ago I don't get
anything like that. In fact, there's no discernable detail beyond
about 9MP with those films, and they look soft even there. (Ektar 25,
on the other hand, is bitingly sharp.)

--
Matthew Winn
[If replying by mail remove the "r" from "urk"]
 >> Stay informed about: Medium format versus digital sharpness 

"Neil Gould" <neil.RemoveThis@myplaceofwork.com> wrote:

> To suggest that this is as good as it gets ignores a lot of available
> PMT-based technology in truly "high-end drum scanners".

Since you seemed to be better hooked into the high end market than
I, how well are drum scanner manufacturers doing these days?

I don't think I've seen any new product announcements from any of
the manufacturers since Creo was acquired by Kodak.

--
Michael Benveniste -- mhb-offer.RemoveThis@clearether.com
Spam and UCE professionally evaluated for $250. Use this email
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 >> Stay informed about: Medium format versus digital sharpness 

"Michael Benveniste" <mhb-offer.RemoveThis@clearether.com> wrote:
>
> When you stop playing semantic games and try to refute my evidence that
> scanners cause resolution losses, I'll be here.

Oh, great! I get to be on both sides of the argument!

While you are, of course, correct that scanning causes losses, if one's
concern is with qualitative differences, not just merely detectable
differences, those losses are, IMHO, too small to be significant.

To the best that I can tell, neither projection printing nor 8000 ppi drum
scanning is going to make 35mm capable of making 12x18 prints that compete
with 12x18 prints from 4000 ppi scanned 645 or 12.7MP direct digital
capture.

In particular, I don't find that the losses associated with 4000 ppi
scanning to be significant. To my eye, the scans look very much like what I
see with my 20x loupe and 60x microscope. Maybe drum scanners or wet
projection printing are better, but if 4000 ppi 645 isn't good enough for a
particular application, one is better off moving to 6x7 or LF than spending
money on drum scans.

(Also, the enlarger lens imposes an MTF term on the image, so projection
printing has its losses too, so it's not clear that scanning is actually
worse.)

David J. Littleboy
Tokyo, Japan
 >> Stay informed about: Medium format versus digital sharpness 

"David J. Littleboy" <davidjl RemoveThis @gol.com> wrote:

> To the best that I can tell, neither projection printing nor 8000 ppi
> drum scanning is going to make 35mm capable of making 12x18 prints
> that compete with 12x18 prints from 4000 ppi scanned 645 or 12.7MP
> direct digital capture.

For 645, I agree with you. At ISO 400, I also agree with you on the
12.7MP capture, but it's a much closer call. With Velvia, to my eye
the two are within experimental error. And for black and white prints,
I still give the edge to Delta 100.

For portraiture, I still prefer film, for subjective reasons having
nothing to do with maximum resolution.


> In particular, I don't find that the losses associated with 4000 ppi
> scanning to be significant. To my eye, the scans look very much like
> what I see with my 20x loupe and 60x microscope. Maybe drum scanners
> or wet projection printing are better, but if 4000 ppi 645 isn't good
> enough for a particular application, one is better off moving to 6x7
> or LF than spending money on drum scans.

Since I find that trying to achieve the highest possible intermediate
resolution to be a futile effort, once again I think we're in
agreement. When it comes to dynamic range, though, to my eye drum
scans still have an edge, even though scanners like the CoolScan
have a higher claimed DMax.

> (Also, the enlarger lens imposes an MTF term on the image, so projection
> printing has its losses too, so it's not clear that scanning is actually
> worse.)

The digital versus analog printing discussion is of much more
interest to me. I'm fortunate enough to have two good general
labs nearby, and one specialist in black and white. A little over
a year ago, one of the general labs switched from projection
enlargements to digital methods. I've had 11x14's done at each since
then. I'll still go with Ilfochrome while I can, but I find the
digital prints from color negatives stand up very well against those
done in a wet darkroom. But once again, my preference has nothing
to do with maximum resolving power.

--
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 >> Stay informed about: Medium format versus digital sharpness 

Michael Benveniste wrote:

> The digital versus analog printing discussion is of much more
> interest to me. I'm fortunate enough to have two good general
> labs nearby, and one specialist in black and white. A little over
> a year ago, one of the general labs switched from projection
> enlargements to digital methods. I've had 11x14's done at each since
> then. I'll still go with Ilfochrome while I can, but I find the
> digital prints from color negatives stand up very well against those
> done in a wet darkroom. But once again, my preference has nothing
> to do with maximum resolving power.

I get a lot of prints made at Costco, which uses a Noritsu model 3111.
Whereas the prints form this look pretty good they don't have near the
resolution that even a cheap inkjet printer has. I have seen some
optical prints that are far sharper then what the Noritsu can produce
but not always.

On the other hand prints from a good ink jet printer have more
resolution then most optical prints I have seen (color). I have heard a
number of people tell me how much better they optical prints are, but
these people have yet to do a test scan on a flat bed scanner so it is
impossible to tell just what resolution they are getting.

The color rendition I can get with a digital work flow, scanning
negatives and having prints made from the digital files, are far better
in overall quality then what I was getting from the labs, the labs often
would blowout highlights and get the color way wrong.

Scott
 >> Stay informed about: Medium format versus digital sharpness 

Recently, Michael Benveniste <mhb-offer DeleteThis @clearether.com> posted:

> "Neil Gould" <neil DeleteThis @myplaceofwork.com> wrote:
>
>> To suggest that this is as good as it gets ignores a lot of available
>> PMT-based technology in truly "high-end drum scanners".
>
> Since you seemed to be better hooked into the high end market than
> I, how well are drum scanner manufacturers doing these days?
>
> I don't think I've seen any new product announcements from any of
> the manufacturers since Creo was acquired by Kodak.
>
There are not likely to be many new high-end drum scanners introduced into
the market for obvious reasons. Convenience, pricing, and need will shape
the market more strongly than image quality, but that doesn't negate the
PMT drum scanners' quality.

There are other important qualities in photographs as well, some of which
you acknowledge in your other post in which you claim a preference for
film for portraiture and drum scans for reasons other than maximum
sharpness (a position with which I am in complete agreement). IMO,
sharpness has its place, but it is not as all-important as some make it
out to be. If those who tout all things digital really wanted maximum
sharpness, they'd never settle for a camera with a soft-focus filter. Yet,
few in the marketplace have insisted on owning a Leica DMR (although the
M8 is doing relatively well). Similarly, they would not settle for
anything short of the results possible from the best lenses, as can be
demonstrated in some comparisons on Gary's Lympalog site:

http://northcoastphotos.com/Lympa_2007_09_29.htm

So, AFAIC, there is far more emotional chatter about this than meaningful
information. As Q.G. points out, we don't need calculations to tell us
what we see or what we prefer in a visual medium.

Neil
 >> Stay informed about: Medium format versus digital sharpness 

Neil Gould wrote:
> Recently, Michael Benveniste <mhb-offer.RemoveThis@clearether.com> posted:
>
>> "Neil Gould" <neil.RemoveThis@myplaceofwork.com> wrote:
>>
>>> To suggest that this is as good as it gets ignores a lot of available
>>> PMT-based technology in truly "high-end drum scanners".
>> Since you seemed to be better hooked into the high end market than
>> I, how well are drum scanner manufacturers doing these days?
>>
>> I don't think I've seen any new product announcements from any of
>> the manufacturers since Creo was acquired by Kodak.
>>
> There are not likely to be many new high-end drum scanners introduced into
> the market for obvious reasons. Convenience, pricing, and need will shape
> the market more strongly than image quality, but that doesn't negate the
> PMT drum scanners' quality.
>
> There are other important qualities in photographs as well, some of which
> you acknowledge in your other post in which you claim a preference for
> film for portraiture and drum scans for reasons other than maximum
> sharpness (a position with which I am in complete agreement). IMO,
> sharpness has its place, but it is not as all-important as some make it
> out to be. If those who tout all things digital really wanted maximum
> sharpness, they'd never settle for a camera with a soft-focus filter. Yet,
> few in the marketplace have insisted on owning a Leica DMR (although the
> M8 is doing relatively well). Similarly, they would not settle for
> anything short of the results possible from the best lenses, as can be
> demonstrated in some comparisons on Gary's Lympalog site:
>
> http://northcoastphotos.com/Lympa_2007_09_29.htm
>
> So, AFAIC, there is far more emotional chatter about this than meaningful
> information. As Q.G. points out, we don't need calculations to tell us
> what we see or what we prefer in a visual medium.

All well and good if you like the look of a film print better, and you
don't care about the sharpness of your images, but the OP asked how many
pixels a digital camera would need to match the sharpness of a 6x7
camera. This has an answer, which is in the range of 20-30 MP.

As for what lens to use, I find a $70 lens give me all the resolution I
want, it is all in how you use it. This photo was taken with a $70 lens
http://www.sewcon.com/largephotos/112_mp_Image.jpg
note that is one large photo so you will most likely need to download it
and open it in a photo editor.

Scott
 >> Stay informed about: Medium format versus digital sharpness 

Recently, Scott W <biphoto DeleteThis @hotmail.com> posted:

> Neil Gould wrote:
>> Recently, Michael Benveniste <mhb-offer DeleteThis @clearether.com> posted:
>>
>>> "Neil Gould" <neil DeleteThis @myplaceofwork.com> wrote:
>>>
>>>> To suggest that this is as good as it gets ignores a lot of
>>>> available PMT-based technology in truly "high-end drum scanners".
>>> Since you seemed to be better hooked into the high end market than
>>> I, how well are drum scanner manufacturers doing these days?
>>>
>>> I don't think I've seen any new product announcements from any of
>>> the manufacturers since Creo was acquired by Kodak.
>>>
>> There are not likely to be many new high-end drum scanners
>> introduced into the market for obvious reasons. Convenience,
>> pricing, and need will shape the market more strongly than image
>> quality, but that doesn't negate the PMT drum scanners' quality.
>>
>> There are other important qualities in photographs as well, some of
>> which you acknowledge in your other post in which you claim a
>> preference for film for portraiture and drum scans for reasons other
>> than maximum sharpness (a position with which I am in complete
>> agreement). IMO, sharpness has its place, but it is not as
>> all-important as some make it out to be. If those who tout all
>> things digital really wanted maximum sharpness, they'd never settle
>> for a camera with a soft-focus filter. Yet, few in the marketplace
>> have insisted on owning a Leica DMR (although the M8 is doing
>> relatively well). Similarly, they would not settle for anything
>> short of the results possible from the best lenses, as can be
>> demonstrated in some comparisons on Gary's Lympalog site:
>>
>> http://northcoastphotos.com/Lympa_2007_09_29.htm
>>
>> So, AFAIC, there is far more emotional chatter about this than
>> meaningful information. As Q.G. points out, we don't need
>> calculations to tell us what we see or what we prefer in a visual
>> medium.
>
> All well and good if you like the look of a film print better, and you
> don't care about the sharpness of your images
>
Well, it seems to me that there is some territory between caring *only*
about sharpness and not caring about the sharpness of an image.

>, but the OP asked how
> many pixels a digital camera would need to match the sharpness of a
> 6x7 camera. This has an answer, which is in the range of 20-30 MP.
>
That's your opinion, and you are entitiled to it. However, having seen and
used many high-end drum-scanned images, I'd have to disagree with those
who are basing their opinion on less than optimal equipment and results.
Also, having seen and used 22-30 MP digital, it looks pretty much like
most digital imagery to me. If that's what you're after, digital capture
is shortest (though not necessarily cheapest) route to that end.

> As for what lens to use, I find a $70 lens give me all the resolution
> I want, it is all in how you use it.
>
However, you'd have admit that a better lens would give you even more
sharpness, or is it that you don't care about the sharpness of your
images? 8-^

Neil
 >> Stay informed about: Medium format versus digital sharpness 

Neil Gould wrote:
> Recently, Scott W <biphoto DeleteThis @hotmail.com> posted:
>
>> Neil Gould wrote:
>>> Recently, Michael Benveniste <mhb-offer DeleteThis @clearether.com> posted:
>>>
>>>> "Neil Gould" <neil DeleteThis @myplaceofwork.com> wrote:
>>>>
>>>>> To suggest that this is as good as it gets ignores a lot of
>>>>> available PMT-based technology in truly "high-end drum scanners".
>>>> Since you seemed to be better hooked into the high end market than
>>>> I, how well are drum scanner manufacturers doing these days?
>>>>
>>>> I don't think I've seen any new product announcements from any of
>>>> the manufacturers since Creo was acquired by Kodak.
>>>>
>>> There are not likely to be many new high-end drum scanners
>>> introduced into the market for obvious reasons. Convenience,
>>> pricing, and need will shape the market more strongly than image
>>> quality, but that doesn't negate the PMT drum scanners' quality.
>>>
>>> There are other important qualities in photographs as well, some of
>>> which you acknowledge in your other post in which you claim a
>>> preference for film for portraiture and drum scans for reasons other
>>> than maximum sharpness (a position with which I am in complete
>>> agreement). IMO, sharpness has its place, but it is not as
>>> all-important as some make it out to be. If those who tout all
>>> things digital really wanted maximum sharpness, they'd never settle
>>> for a camera with a soft-focus filter. Yet, few in the marketplace
>>> have insisted on owning a Leica DMR (although the M8 is doing
>>> relatively well). Similarly, they would not settle for anything
>>> short of the results possible from the best lenses, as can be
>>> demonstrated in some comparisons on Gary's Lympalog site:
>>>
>>> http://northcoastphotos.com/Lympa_2007_09_29.htm
>>>
>>> So, AFAIC, there is far more emotional chatter about this than
>>> meaningful information. As Q.G. points out, we don't need
>>> calculations to tell us what we see or what we prefer in a visual
>>> medium.
>> All well and good if you like the look of a film print better, and you
>> don't care about the sharpness of your images
>>
> Well, it seems to me that there is some territory between caring *only*
> about sharpness and not caring about the sharpness of an image.
>
>> , but the OP asked how
>> many pixels a digital camera would need to match the sharpness of a
>> 6x7 camera. This has an answer, which is in the range of 20-30 MP.
>>
> That's your opinion, and you are entitiled to it. However, having seen and
> used many high-end drum-scanned images, I'd have to disagree with those
> who are basing their opinion on less than optimal equipment and results.
> Also, having seen and used 22-30 MP digital, it looks pretty much like
> most digital imagery to me. If that's what you're after, digital capture
> is shortest (though not necessarily cheapest) route to that end.
Well two things here, the first if the OP is probably not talking about
drum scanned images, and I have yet to see a link to an example of a
drum scan image that shows any significant improvement in resolution.

What I have seen are drum scans that at 4000 ppi are very soft, Rafe B.
has a nice page showing different scans
http://www.terrapinphoto.com/jmdavis/
Here is what I see in a 4000 ppi drum scan
http://www.terrapinphoto.com/jmdavis/john_v.25x.25.jpg
That is a drum scan using a Howtek 4000, the film was 6x7, Velvia 50.

I do believe that a drum scan can help reduce the noise in a scan and in
some cases improve the dynamic range but I have yet to see a drum scan
with much more then 2000ppi of real resolution. I have also yet to see
the makers of a drum scanner post any samples from their scanners, which
seems kind of odd.

>> As for what lens to use, I find a $70 lens give me all the resolution
>> I want, it is all in how you use it.
>>
> However, you'd have admit that a better lens would give you even more
> sharpness, or is it that you don't care about the sharpness of your
> images? 8-^

To take any sharper images I would have to have reduce DOF ( buy going
to a longer lens), which for many of my images would be a problem. This
BWT is what often limits the resolution of LF images, many of which
are shot at f/32 to f/64. At f/64 you are not going to come close to
getting all the detail that the film is capable of recording.

Scott
 >> Stay informed about: Medium format versus digital sharpness