On 3/5/2011 11:24 AM, Bob Whitmire wrote:
> Actually, I'm kinda partial to the Epson with new holder. Seems to have more
> pop. If I were Moose, I might test to see if I could get that pop with the MF
> scanned image, but I'm not, so I won't.
Nor will I. I can say, as I you will see below, that the result of PP on the
Minolta scan should be better than can be
achieved working with the Epson scans.
> On Mar 5, 2011, at 12:37 PM, Nathan Wajsman wrote:
>> . . .
>> My own conclusion is that the film scanner delivers slightly more sharpness
>> but the Epson more than holds its own when it comes to dynamic range.
>
These samples just don't provide what's necessary to determine which is the
best scanner, for a few reasons:
1. I have both a 4000 dpi 35mm film scanner, Canon PS4000, and 4800 dpi flatbed
scanner with film capability, Canon
9950F. The capabilities of your V700 and 9950F are VERY close. I spent a lot of
time researching this before buying. I
have done careful comparisons of film scanned at the maximum resolutions of
each. In spite of the higher nominal
resolution difference, the film scanner does extract slightly more detail.
However, you are not going to see it in an image down sampled to 2,000 pixels,
30% of the original scan's 6,800. With
6x9 cm film, @ 4800 dpi, the long side is 17,000 pixels, and 2,000 is only 11%.
If I can't see the difference in a 30%
image, there's no way anyone can see the full difference in you scans at 11%.
Of course if you scanned at higher
resolution, the problem would be even greater.
2. The differences in this case are greater than just the scanners used.
Software capabilities and/or operator choices
make meaningful comparison difficult. The exposures are considerably different.
There are considerable clipped
highlights in the Epson scans, while the shadows just touch the bottom of the
histogram. The Minolta scan just kisses
the top, with a little bit of clipping at the bottom.
I do have to disagree with Nathan that ". . . the Epson more than holds its own
when it comes to dynamic range." Based
on the images shown, the Epson would seem to have poorer dynamic range, i.e.
more clipping. There is certainly quite a
bit of detail missing in the Epson scans on the gravel road and the rocks in
the wall through clipping. The Epson
software may have settings to correct that problem.
However, I doubt that any of the difference is inherent in the scanners. How
much of it is in the software and how much
in operator settings, I obviously can't know. I do know that I never did figure
out how to get scans that didn't tend to
highlight clipping and excessive contrast with the Canoscan software that came
with the 9950F. With VueScan, I have full
control and get image files directly comparable in tonality to those I get from
the film scanner using VueScan.
This difference has two major consequences:
2a. Make a batch of images, print or web with two versions of each, one that
you feel is ideal for the subject and one a
bit brighter, with higher contrast. Show them to a bunch of people and ask
which is better. The vast majority will pick
the brighter images. It's just the way our visual systems work. It's why all
those automated prints are so bright and
all the outdoor ones have blown out skies.
It you want to compare, or have others compare, image aspects other than
brightness and contrast, it's of great
importance to match brightness and contrast. Now Bob's a helluva photographer,
processor and printer, but in a quick
look, he chose the middle image, for it's 'pop', greater brightness and
contrast. But the choice had nothing to do with
inherent scanner differences.
People casually looking are going to tend to pick the Epsons for those reasons,
and the one of those made with cool new
stuff you spent money on, 'cause it's bound to be better, isn't it? - and
making close comparisons is hard work.
2b. The first place my eye tends to look when asked about resolution is one
where fine detail is against low detail
background, in this case, twigs against sky. But there's a problem there. It's
the same problem I run into in lots of
images I see and, unfortunately, in all to many I take. Where dark, fine detail
is against bright, low detail
background, digital imaging systems tend to lose the edges, and especially so
when the background is at or near clipping.
The bright part seems to bleed over into the dark part. I know this can be at
least in part an optics issue. I've seen
it clearly when observing a small bird against bright, blank sky, alternating
between good and great binoculars. I also
know it can happen in digital sensors when electrons 'spill over' from sites
that are clipping and affect adjacent
sites. I believe a lot of the improvement in sensors over the last few years
has been in controlling this effect.
Whatever the immediate cause(s), it's very clearly happened on the Epson
images. So it's really impossible to tell how
much of the apparently greater detail capture on the Minnie in the tree-sky
area is real and how much an artifact of
this bleeding effect.
Finally, how about that resolution? I said above "there's no way anyone can see
the full difference in you scans at
11%", and I still believe that to be true. However, simply comparing the three
images closely, there are some
differences between them. Assuming all three were processed, sharpened and down
sized the same way, it may be valid to
suppose that they reflect differences in full size resolution. I say "may",
because both how they were downsized and
how they were sharpened could account for differences.
It's really impossible to make a close comparison on the web, so I downloaded
them and overlaid them as layers in PS, so
I can flip between them without moving my eyes.
The first thing I found is that the first image, with standard V700 film
holder, is distinctly sharper than the one with
the new holder. The best areas of fine detail not affected by bleeding are, I
think, the grasses. On the lower middle
left and middle right, they clearly have finer, sharper edged detail. In the
middle, above the rock wall, the difference
appears to be less. On film this size, that may well be, at least in part, lack
of flatness.
If this new holder is supposed to hold the film flatter, and appears to do so,
how could this be? The simplest, and most
pleasing, reason could be if the two images are mislabeled. ;-) Otherwise, it
could be imperfect focusing of a shallow
DOF scanner lens system combined with still not quite flat film. If the
different holder moved the film plane slightly,
and the scanner was not refocused or imperfectly refocused, that could also
explain the difference.
In any case, with these two particular test scans, the new holder is either
worse or the images are mislabeled.
Now, Minnie vs. Eppie. :-) M does seem to resolve grass detail slightly
better than E, but the difference sure is
small, and it's hard to ignore, or 'look through' the tonal differences. Given
all the other variables, I'm not sure I
could firmly conclude that the film scanner is significantly better, based on
these samples.
Given that you aren't going to be making wall size prints, an based on these
images, I'd just send back the fancy
holder, ignore any need for a better scanner and learn how to get a better
basic scan out of the V700. You might read
Vincent's detailed review of the V700 on photo-i to get some further ideas
about how to get the best out of it.
<http://www.photo-i.co.uk/Reviews/interactive/Epson%20V700/page_1.htm>
A. Critical Moose
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|