After scanning some 1,800 rolls, I admit to having grown a
little complacent, naively thinking I've seen it all. However,
some recent experiences, giving me a bit of a wake-up call, may
be of interest.

A large batch of 58n Aeolian Grand organ rolls have just been
loaned to me. Some months back, I modified my scanner to
accept 58n rolls and Kevin kindly provided me with modified
versions of SCN58.EXE and MID58.EXE. With an earlier batch
of 58n Wilcox & White Symphony organ rolls, all went well.

The very first first Aeolian Grand roll I scanned proved to be
quite troublesome as the paper is quite poor. Visually in
good condition, but the instant the roll began to unwind, it
became apparent I would have trouble achieving a good quality
roll image.

The paper is a trifle thinner than later early-teens 88n roll
paper, but opacity is not consistent. In a number of areas
of this roll, it was somewhat translucent, while in other areas,
quite opaque. Made it very difficult to strike a balance
between a good quality image vs frequency of random blooms.

The CIS software processes a line of data as changes between
light and dark. Every change requires 2 bytes. Many
changes will inflate file size extraordinarily. A good clean
roll image has fewer changes, so file size is dramatically
smaller.

This 58n troublesome roll, with exposure turned down to an
absolute minimum, produced hole images very poorly formed.
Close examination of the lines of data revealed numerous changes
light to dark and vice versa. First scan with no random
blooms, but poorly formed hole images, generated a mammoth 30
meg CIS file (11 minute tune).

A subsequent scan of the same roll, with more normal hole
images, produced a CIS file only 8 megs big. However, the
price was excessive random blooms, one so bad as to force a
rescan. Screen dump examples of this can be seen at:

http://members.shaw.ca/paud122/software.htm

Something else quite strange I noted..... As I cut back
severely on exposure, the optical encoder's square wave on
screen became ever more tighter. As I increased the
exposure, the square wave lengthened out to something more
normal, along with a normal screen image, as I ordinarily get
with 88n rolls.

I switched back over to 88n rolls and tried the same experiment.
CIS.EXE same in both cases. As I reduced the exposure almost
to the point of image disappearance, the square wave becomes
ever more tighter. At the point of image disappearance, the
square wave suddently becomes elongated, about twice as long as
during normal exposure.

Going the other way, as I progressively increase the exposure to
the point of loads of noise, the square wave becomes
progressively tighter. As the screen fills with data,
the square wave is extremely tight. In all cases, I've left
the encoder jumper alone. Still in central position.

Not sure how I'm going to deal with these 58n rolls, most
perforated on paper comparable to early-teens 88n. These
should not be a problem. But for a few of these early
rolls, about 1895-96, the paper quality is very poor.
Visually the rolls are fine, all appearing in good condition.
But most are extremely fragile, requiring very careful
manual rewind. A few are not only fragile, but have
inconsistent opacity.

This project, to scan about 300 of these Aeolian Grand rolls, is
providing very strong support for preservation of the content of
these old rolls before they self-destruct
completely. Thanks to a number of determined skilled people,
Richard Stibbons in particular, the ability to preserve roll
content may well be arriving just in the nick of
time.

Hopefully, others will soon have additional roll scanners up and
running, and the library of scanned rolls will increase
dramatically. Ross Chapman in Australia now has his
scanner up and running, and he kindly shared with me about 50 of
his Duo-Art scans which I posted within my last batch 12 on my
personal web site. See:

http://members.shaw.ca/smythe/library.htm

In recent weeks, 3 more people have acquired MK3a systems which
hopefully will produce more working scanners within our little
community. Quite encouraging.

Stay tuned.....

Regards,

Terry

Terry Smythe 204-832-3982 (land line)
55 Rowand Avenue 204-981-3229 (cell)
Winnipeg, MB, Canada R3J 2N6 smythe@...
Preserving our Musical Heritage
http://members.shaw.ca/smythe/rebirth.htm