[rollei_list] Re: ADMIN: Petr's tone
- From: CarlosMFreaza <cmfreaza@xxxxxxxxx>
- To: rollei_list@xxxxxxxxxxxxx
- Date: Fri, 27 Nov 2009 01:13:26 -0300
2009/11/26 Petr Dvorak <pdvorak@xxxxxxxxx>:
> Carlos,
>
> I am lost in the translation and fail to follow your logic even if we remove
> the V700 from the picture. Please bear with me for a moment and answer yes
> or no to these questions:
> 1. Epson says: for some of the newer scanners (single-lens fixed focus), the
> focus and best film position is above the glass: yes/no
yes
> 2. You say: I interpret that "above the glass" means "on the glass": yes/no
yes
> 3. Epson statement therefore is (as you put it in your email): the best
> focus can be obtained on the glass: yes/no
yes
> 4. You say: we should scan from the bed on all Epson scanners, you will get
> the best results: yes/no
Yes, at least Epson states that it is the point, however there are
other conditions to evaluate in the scanning process like film
flatness and the Epson holder puts the film almost on the glass
assuring the film flatness -at least a reasonable film flatness-
simultaneously.
> I suggest you look at the two sites below who did extensive testing of focus
> plane position on single lens fixed focus scanners like your 4990; and then
It was a typo, my scanner is the 4490, anyway my scanner is included
in the first site too. BTW I just measured the film height on the
glass using the Epson MF holders, it's about 0.5mm or .5mm and then I
did not find interesting those holders, I know that site from some
years ago and read it several times and watching the results I
obtained from my scanner with the standard holder and scanning on
glass, I never wanted to buy one of those holders.
> you may perhaps re-evaluate your assumption that "when Epson says above the
> glass, Epson says on the glass" (those are your words in the email below). I
> know that no two scanners are alike and that they are subject to individual
> manufacturing and calibration variations,
Yes, it's true that no two scanners are alike, like two camera lenses
are not alike, but according my limited experience with scanners, I
doubt those differences could be enough to justify to change holders,
etc., I don't know the way the scanner focus is adjusted in factory.
Several aerial cameras have different lenses or the same lens but
have the focus adjusted to infinity. I could think that the scanners
focus is adjusted for the same point in spite of the manufacturing
difference and I also could think that the scanner lens DOF has to do
with the manufacturing differences control . I don't know the way the
film flatness is controlled in the tests you are mentioning. BTW, it
could happen that some scanners out of the factory specs calibrations
could need those no standard holders.
but I am still puzzled by the
> bravery of your generalizations without you respecting the same even if your
> scanner gives you wildly different results from the experience of others
> (with the exception of the two gentlemen that you reference).
I did not generalize, the Epson document generalized, but I must say
that my scannings on the scanner glass never were worse than using the
film holder, they were similar or better slightly.
Carlos
PS: BTW, there more than two gentlemen scanning on the scanner glass
in this group.
> http://www.betterscanning.com/scanning/vb_advantage.html
> http://www.normankoren.com/Tutorials/Epson_flatbeds.html#Focus_spacing
> I am also suspecting that your issue with scanning of underexposed slides
> could be attributed to the varying intensity of light transferred through
> your negatives (which may vary with the distance of the film to the photo
---
Rollei List
- Post to rollei_list@xxxxxxxxxxxxx
- Subscribe at rollei_list-request@xxxxxxxxxxxxx with 'subscribe'
in the subject field OR by logging into www.freelists.org
- Unsubscribe at rollei_list-request@xxxxxxxxxxxxx with
'unsubscribe' in the subject field OR by logging into www.freelists.org
- Online, searchable archives are available at
//www.freelists.org/archives/rollei_list
Other related posts:
