Re: 6X6 digital backs (O.T.)

[David Spellman <david@photopro.com>]

"Rafe B." wrote:

> At 06:36 PM 6/28/99 -0700, David Spellman wrote:
> >
>
> >    The digital scanbacks are exactly the same as a flatbed-type scanner,
> featuring
> >a moving CCD array bar that makes a total exposure from a series of
> "strips." The
> >only difference is that the optical system is that of the camera itself.
>
> Not entirely true, David.  I made this
> same statement a few weeks ago on rec.photo,
> and was corrected by a sales/marketing person
> from SinarBron.
>
> He pointed out that their Leaf Volare, for
> example (rather extreme example, perhaps)
> uses a 6 MPixel CCD area array (2K x 3K
> pixels) having an area of 24 x 36 mm.

    That's why I specifically mentioned SCANBACKS in that sentence, rather
than array-type backs, and why I mentioned array-type backs in a following
sentence.

    My statement was/is absolutely correct.

    The Leaf Volare is, as you note, is an array-type back that uses the
Phillips chip. In Sinar's implementation, however, the system is a three-shot
back, requiring red, green and blue filtration in succession to make a single
shot.
    In other implementations, the chip is a full-color single-shot capture
back (and can be used on location with a battery pack) that fits on the back
of a Hasselblad. I'd be interested in seeing comparisions between a file from
the Canon scanner of scanned film, a digital file from the Phillips-chip back
and the original subject matter for color accuracy, dynamic range and detail
rendition.


> The CCD array is made by Philips Semiconductor,
> and I even found the data sheet for it on
> Philip's web site.  (Afraid to ask the cost!)
>
> I wonder if it's the same array that's used
> on the Kodak DCS-560/620?

    It is not. The Kodak array chip is smaller, and made by Kodak. The
Phillips chip, despite the fact that its taking area is exactly the same size
as a 35mm negative, is overall too large to fit into the Nikon and Canon
bodies Kodak is using for these camera systems.

> However, you wouldn't be able to use it for
> anything other than studio or still-life work.

    That would also be incorrect.

    The Dicomed back we have, while certainly requiring a computer, produces
a file larger (48 MB at 24-bit color) than that mentioned by the original
poster (who produced, I believe, a file of about 20 MB) with better color
fidelity and resolution than 35mm film scanned through a $700 Canon film
scanner.

    The back is a single-shot capture back and will fit on either a 4x5
camera or on a Hasselblad, and we've already done shots involving people, on
location. Other backs, including the new Phillips chip back from Phase and
one currently in beta from Sierra-Dicomed, have more than enough capability
to be used on location in action situations.

    david


-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Please: Stay on topic. Trim quoted messages.
http://www.leben.com/lists for list instructions.