On 1/5/2014 12:31 PM, Chuck Norcutt wrote:
>
> On 1/4/2014 6:22 PM, Moose wrote:
>> On 1/4/2014 7:07 AM, Chuck Norcutt wrote:
>> ...
> Well, perhaps I should check focus more carefully. Maybe that's why I
> didn't find more than 2400 dpi necessary. :-)
It's sufficient, often more than sufficient, for a great many images. If
scanning for the web or modest print size,
there's not much point in more.
>>> I have VueScan but haven't been able
>>> to get it to work with film because it doesn't know the locations of the
>>> negatives and slides in their film holders. There is a training process
>>> one is supposed to use to teach it where the frames are but my one
>>> attempt at using it didn't work. One of these days (when I get much
>>> more serious about scanning the many thousands of film images I have)
>>> I'll get back to it and figure out what I was doing wrong.
>> Before going to all that trouble, you should try the latest update. If that
>> doesn't work, drop Ed a line. The profiles
>> for scanners are supposed to know where the film is in standard holders.
>> He's always been very responsive when I've had
>> trouble with VS.
> Either the latest update or maybe just checking more carefully. I don't
> recall any mention of film holder profiles for the V700. I didn't know
> there was such a thing. I don't have the scanner with me but did just
> search the user's manual for the term "multi crop" which is what is used
> to describe multi-frame film holders.
I don't think the custom choices show up until connected to the scanner. With
9950F connected and selected,
Input:Mode:Transparency, Crop:Multi crop gives several choices:
Off
Auto
Custom
35mm slide
35mm film
MF
4x5
The last four choices are for the specific film holders that come with the
scanner, with preset locations for the
frames. Obviously, "35mm film" assumes the strips are placed correctly.
> There's an "auto" setting. When
> I selected auto it filled in some numbers for the little HP
> print-scan-copy machine I have here and identified it as the scan
> source. Maybe that's all I'll have to do when I get home and get the
> V700 reattached. But that same menu selection area has the option for
> custom building a multi-crop profile.
I've used that for something in the past. A bit fiddly, but it worked. Still,
the preset defaults for film holders
should do the trick.
> That's exactly what I tried to do
> so don't know why I missed the auto setting. Of course, what I was
> running at the time was probably several versions back. Maybe it wasn't
> there then for the V700. Anyhow I'll look harder when I get back home.
>
>> A word about scanner resolution ...
> In a book I have at home called "Image Clarity" by John Williams
> (published 1989/90 and 2012 in Kindle form)
> <http://www.amazon.com/Image-Clarity-High-Resolution-John-Williams-ebook/dp/B008KL8J54/ref=sr_1_22?s=books&ie=UTF8&qid=1388951601&sr=1-22&keywords=image+sharpness#reader_B008KL8J54>
>
> Williams spends many pages <big snip> Resolution of low contrast areas in
> typical
> color films only ranges from about 50 to 80 lines/mm and perhaps double
> that in high contrast areas. No matter how good and stable the lens the
> end result can't be better than that and will likely be appreciably less.
It all sounds very serious and professional. But it doesn't MEAN anything to
me. I don't know how to translate it to my
actual images. What lp/mm reading translates into what dpi, on which scanner?
4800 dpi on the 9950F doesn't resolve
quite as much fine detail as 4000 on the FS4000. Where do things like that
figure into all the testing and numbers?
I'm not trying to disparage a lot of work, it's just that I can't figure out
how to use it as a practical matter.
I DO know, from experiment, at what point higher scanner dpi doesn't extract
more detail, which is what I reported:
>
>> "Well, yes and no. A carefully focused shot with a good lens at a good
>> aperture on film from the last couple of decades,
>> at least, does reveal significantly more detail at 4000 dpi than 2400. In
>> fact, I've been able to slightly increase
>> pixel level detail with multiple scan passes in VueScan. It's quite time
>> consuming, although one may be elsewhere while
>> it's happening. But if making a large print from a good frame, it could be
>> worth it.
>>
>> I did a fair amount of careful testing, mostly on Portra 160, not the later
>> couple of versions, which are said to be
>> even better.
>>
>> Then again, what you say is also true, both of a great many images and of
>> the needs of modest print sizes. Kodak 200
>> film in an XA some years earlier had nothing extra at 4000 dpi."
The image I worked with the most was taken with a tripod on a path in woods.
Great dynamic range, from deep shadow to
leaves in direct sun. Lots and lots of fine, natural detail in foliage, etc. As
I said, much more detail visible at 4000
dpi than 2400 and even a little bit more with multi-scan.
I've got a lot of old film yet to scan. Usually, I know what the film is, but
often not the lens. In practice, if I used
one or two films and one to three lenses on a trip, it doesn't take long to
determine what is the optimum scanning dpi,
and just use that. I think that's really simpler and more reliable than reading
about a bunch of testing with different
films, lenses and scanner.
The book also seems a little out of date, in that some color neg films have
increased their resolution, both in absolute
terms and in being optimized for scanning. Also, I suspect the data about
resolution in low contrast areas doesn't take
into account the ability of post processing to bring out detail.
Scanning for Truth Moose
--
What if the Hokey Pokey *IS* what it's all about?
--
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