HP 6250C and scanning 35 mm slides

[Don R.]

Just checked the cover. It's much too thin to be able to accomodate
any sort of light source. Other than being sinmply a good document
scanner, it has the ADF feature, which utilizes the lid.

BTW, have you seen the message by Fred Toewe? He has the same scanner
and explains what's going on. I'll append it below just in case.

That pretty much says it all, doesn't it.

That's one option, but a couple of considerations. They will not put
the effort you will! For them it's just work. Now, they are
professionals (hopefully! ;o)) so it will spare you a steep learning
curve, but - at least in theory - you could produce much better
results if you have the time.

I'm not sure I'd be able to find anyone who is really a pro in this
location.

If you decide to do it yourself, I second wholeheartedly what Ken
Weitzel said. Do get a dedicated film scanner! They are not really
that expensive, and when you're done you can sell it and recover some
of the cost. But the difference between even the best flatbed and a
dedicated film scanner is really night and day. Some film scanners
also have a hardware based "cleaning" mode which automatically
eliminates dust and scratches which makes editing afterwards much
easier. Of course that means having to get an image editing program...

I do have Adobe PhotoShop 5.5, Adobe ImageReady 1.0, Adobe Photo
Deluxe BE 1.0, all of which I've had for some time and am not
proficient in any of them. Obtained them some years back when Adobe
employees were able to buy them at very low price.

I also have Olympus' Camedia Master 4.1 which came with an Olympus
C-5060 digital camera I recently purchased.

I'm wrestling mostly with 1980s Kodachromes and that's a horror story
in its own right! ;o)

Mine are mostly Kodachromes, too, plus some other brands.

And here's that message I refer to above:

Thanks!

Spent some time chatting with a Dell sales rep this morning. He/they
recommend Visioneer scanners for slides and film. Noticed one is made
by Xerox, don't know if they all are. . . have seen references to
Visioneers in this NG. I'll ask about them in a separate post so more
are likely to see it.

Really appreciate everyone's input.

Don R.
<[email protected]

 

[Roger]

Looks that way! :-(

I have a 5470c which has an adapter that goes on top. This adapter
consists of a plastic plate and a film holder that fits into the
center of the plastic plate. You lift the center piece out and slide
a film strip containing up to as many as four negatives or
transparencies.

But this only uses a small percent of the total scanner area.

As others have said, a dedicated film and slide scanner will do a far
better job and you can get a really nice one new in the $500 US range,
then sell it on E-Bay after you are done.

I use a Nikon LS5000ED which is a bit more money but was worth it, "I
think", but I've gone through more than 20,000 scans. Actually I've
lost track of just how many I have done as I ended up redoing a bunch.
However I plan on keeping the LS500ED.

http://www.rogerhalstead.com/scanning.htm may help with some
decisions.

BTW, have you seen the message by Fred Toewe? He has the same scanner
and explains what's going on. I'll append it below just in case.

Many camera shops have this capability as do photo finishers.
HOWEVER you need to find out ahead of time at what resolution they
scan and at what price!

The local photoshop uses a Nikon scanner for slides and film strips. I
don't know if the charge is the same for all, but they get a buck a
slide. OTOH I'd rather pay $1.00 US for a 4000 dpi scan (they will
clean the slides if necessary and know how to do it) than 50 cents for
a screen resolution slide on a CD.

Of course at 4000 dpi you can use a lot of CDs when you consider at
an 8 bit color level the images are roughly 60 megs each, which is
about 12 per CD, or 120 megs at 16 bit color depth which is about 6
images per CD.

That's one option, but a couple of considerations. They will not put
the effort you will! For them it's just work. Now, they are
professionals (hopefully! ;o)) so it will spare you a steep learning
curve, but - at least in theory - you could produce much better
results if you have the time.

Which all boils down to what type of output you are after and if you
have the time and can spare the added expense.

You usually pay for what you get and sometimes you pay for what you
don't get.

If you decide to do it yourself, I second wholeheartedly what Ken
Weitzel said. Do get a dedicated film scanner! They are not really
that expensive, and when you're done you can sell it and recover some
of the cost. But the difference between even the best flatbed and a
dedicated film scanner is really night and day. Some film scanners
also have a hardware based "cleaning" mode which automatically
eliminates dust and scratches which makes editing afterwards much
easier. Of course that means having to get an image editing program...


I'm wrestling mostly with 1980s Kodachromes and that's a horror story
in its own right! ;o)

Those can be real bears. I just went through many thousand of the "old
family slides" and nearly all were Kodachrome 25. ICE did not work on
many, but on those it did it was worth it.

Some of them had faded to just a greenish cast and the scanning
"restore faded slide" function made them look like the originals, or
as near as my memory could tell.

Of course the old paper mounts have that tendency to curl and/or have
the edges spread out. <)

Good luck all,

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

 

[Don]

I'm not sure I'd be able to find anyone who is really a pro in this
location.

In that case you may just as well do it yourself. After all you've
done scanning with the flatbed and using a film scanner is not all
that different. There are some differences (e.g. focus) but you have a
head start!

I do have Adobe PhotoShop 5.5, Adobe ImageReady 1.0, Adobe Photo
Deluxe BE 1.0, all of which I've had for some time and am not
proficient in any of them. Obtained them some years back when Adobe
employees were able to buy them at very low price.

Oh well, you're all set then! That also means you're familiar with the
software and the whole editing process.

I also have Olympus' Camedia Master 4.1 which came with an Olympus
C-5060 digital camera I recently purchased.


Mine are mostly Kodachromes, too, plus some other brands.

In that case do note that Nikons have a problem with Kodachromes! :-(

On the other hand, for other slides and for negatives Nikons are
really fantastic because due to 3 separate light sources they have
exceptional color purity. Also, LED light source in Nikons does *not*
deteriorate with time! Conventional light source used in other
scanners (with the exception of Minolta 5400 Mark *II* - not Mark I)
those conventional light sources deteriorate and drift over time
eventually burning out.

Nikons also produce very sharp scans which sometimes makes the grain
more apparent. But, the way I see it, you can always "blur" the grain
using various grain reduction methods or 3rd party software. It's much
more difficult to get that sharpness back, unsharp mask
notwithstanding. So, on balance, I for one prefer grain to a fuzzy
scan.

Don.

 

[Don]

I have a 5470c which has an adapter that goes on top. This adapter
consists of a plastic plate and a film holder that fits into the
center of the plastic plate. You lift the center piece out and slide
a film strip containing up to as many as four negatives or
transparencies.

But this only uses a small percent of the total scanner area.

I think the reason they only use a small area is because the middle is
probably the "sweet spot" of a flatbed. And since flatbeds struggle
with film anyway at least they make sure one uses the best area.

I use a Nikon LS5000ED which is a bit more money but was worth it, "I
think", but I've gone through more than 20,000 scans. Actually I've
lost track of just how many I have done as I ended up redoing a bunch.

That's exactly why Nikon's LED light source is superior (in terms of
longevity and reliability). Not only is it still going strong but even
after 20,000+ scans it hasn't changed its characteristics. I suspect
if you did that with a conventional light source scanner, the lamp
would have either burned out by now or drifted so much that it would
have to be replaced anyway.

However I plan on keeping the LS500ED.

Even though I'm not planning to go back to analog, one never knows...
So I'll probably keep mine as well, when I'm done. After all, the
resale value (even though pretty good for Nikons) is a fraction of
what I paid so I may just as well keep it.

Many camera shops have this capability as do photo finishers.
HOWEVER you need to find out ahead of time at what resolution they
scan and at what price!

And the quality of edits!

You usually pay for what you get and sometimes you pay for what you
don't get.

Indeed! ;o) That's what I was warning about.

Those can be real bears. I just went through many thousand of the "old
family slides" and nearly all were Kodachrome 25. ICE did not work on
many, but on those it did it was worth it.

I find ICE works (LS-50 here) on overexposed Kodachromes where all the
silver has been washed out. On normal or underexposed ones it doesn't
really work. But often times one really has to struggle to see it and
inspect the image carefully at ~300% magnification to notice it. It's
a subjective call whether to use ICE on Kodachromes.

My main problem with Kodachromes is noise in dark areas (now fixed by
scanning twice) but most of all the notorious blue cast!

That Nikon blue cast on Kodachromes will be the end of me! ;o)

Some of them had faded to just a greenish cast and the scanning
"restore faded slide" function made them look like the originals, or
as near as my memory could tell.

Of course the old paper mounts have that tendency to curl and/or have
the edges spread out. <)

Yes! Half of my Kodachromes are in cardboard mounts and the film
itself has acquired "pincushion" distortion which makes it very hard
to focus! Add to that the relatively narrow depth of field of Nikons
and it's yet another nightmare. :-(

In my experiments I find that +/- 3 clicks is acceptable range where
things are still in focus. The trouble is the difference between the
middle of a mounted slide and the corners is often > 20 clicks! So I
now focus on the object of interest and try to have that in focus as
much as possible. On the "plus" side the areas out focus have less
visible grain! ;o)

Don.

 

[Don R.]

Oh well, you're all set then! That also means you're familiar with the
software and the whole editing process.

Hahaha. Guess you missed my statement, "all of which I've had for some
time and am not proficient in any of them". I wish I was familliar
with the software and the editing process. Guess I'd better do some
studying and practice.

On the other hand, for other slides and for negatives Nikons are
really fantastic because due to 3 separate light sources they have
exceptional color purity. Also, LED light source in Nikons does *not*
deteriorate with time! Conventional light source used in other
scanners (with the exception of Minolta 5400 Mark *II* - not Mark I)
those conventional light sources deteriorate and drift over time
eventually burning out.

I'll check them out. Thanks.

Don R.
<[email protected]

 

[Don]

Hahaha. Guess you missed my statement, "all of which I've had for some
time and am not proficient in any of them". I wish I was familliar
with the software and the editing process. Guess I'd better do some
studying and practice.

LOL. I know what you mean. When I look at my first edits now I roll my
eyes!

That's why I think it's important to scan raw and archive. That way,
as you get more proficient, if you don't like the edits later you can
always go back and start again without having to re-scan. And by then
the film would have deteriorated further too!

Don.

 

[theo]

They're mostly slides taken back in the 1940s and 1950s of my children

that's two retired years,lots and lots of time invested into it, and the
end isn't even in sight yet
35mm negatives, 35mm slides, and pics for which I have no negatives. And
old 120 negatives, disc negatives. Lots.

Having said all that, I promise that it's a very worthwhile task, I
know the kids and grandkids appreciate it and enjoy them. Hope that
at least a couple of generations further down the road do to.
..and others here are going to encourage you to consider a dedicated
film scanner. Speak up,
dedicated guys

Ditto on the film scanners plural! For the <= 4x6 prints I like the
mini-ADF set-top of the Epson 2480 Photo LE. However for the 35mm and
superslides (126 square) and 120 format 6x6 and 6x4.5 and 620 films, negs
and diapos, I used Kodak 3570 and Minolta Dimage Scan Multi ( Pro upgrade
is free) procured via online auctions (eBay is of course the biggest but
not the only bear in these woods) because their film carriers were built
for day in&out use. Their sw are still available at mnfr web sites. But
with lack of mnfr repair support, your $300-500 investment has no future
value so caveat emptor.
And for the online sellers who do not include the film carriers, closely
question the phone folks at B&H or Adorama about availibility BEFORE you
bid because the offerings on their web stores may not truly track
inventory - these two kept me optimistic with back order assurances for
more than four MONTHS!
Hence my tagline.
Theo

 

[Ken Weitzel]

LOL. I know what you mean. When I look at my first edits now I roll my
eyes!

That's why I think it's important to scan raw and archive. That way,
as you get more proficient, if you don't like the edits later you can
always go back and start again without having to re-scan. And by then
the film would have deteriorated further too!

Don.

Hi...

I have one more suggestion to add, for the benefit of OP Don, that he
might like to consider.

Suggest that when you first get started, that you pick out a few
interesting slides/pieces of film, choosing a mix of under-exposed,
real nice, and a bit over-exposed.

Then do those one's over and over, practicing as it were, until you have
some of the skills down pat. Only then begin scanning and saving in
earnest.

So very easy to look at your first couple on the monitor, be truly
impressed, and then keep going.

Then after you've done, say, a couple of hundred you find out that a
slight change that had gone un-noticed makes a huge diffence for the
better, and have to start all over again. And again. And again!

Don't ask me how I know, eh?

Take care.

Ken

 

[Roger]

I have many thousands of mostly slides (The old Family Slides" from
the 40's through the 70's. Then negatives that come up to current
along with 35mm transparency film strips. I only have a few thousand
of those left, but then I get into the really old stuff. "Petrified
Cardboard" prints back into the early 1900's and even a few tintypes.
That groups comprises of probably several hundred pounds of prints.
Then there are some old family albums.

A lot of the images are not even labeled. Some that are I haven't been
able to decipher. So, I'm putting together some CDs of screen
resolution scans to send out to each side of the family, and
particularly the historians/genealogy experts. I'll let them try to
figure out who is who.

All of the 35 mm stuff has been done on a Nikon LS5000ED. I'd sure
hate to have tried to do that many on a slower scanner. After well
over 20,000 I've not had to change any settings.

I only have a few of the larger negatives so I'll have the local
camera shop scan those, or I'll set up a copy stand. I could go
through setting up the enlarger and making some 8 X 10's but that is
one whale of a lot of work compared to scanning although I still do
have the full set up.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

 

[Don]

Then after you've done, say, a couple of hundred you find out that a
slight change that had gone un-noticed makes a huge diffence for the
better, and have to start all over again. And again. And again!

Don't ask me how I know, eh?

LOL.

I lost track how many times I had to restart! Like I said before. I've
done quite a few things in my life but nothing has been so full of
"gotchas" (and so frustrating) like scanning.

Just yesterday I was blind sided by a new "out of left field"
Kodachrome/Nikon trap. I've been going on all cylinders scanning my
Kodachromes (blue cast and all...) when all of a sudden on the latest
film I get a massive red cast!?!? Huh?

Puzzled, I tried scanning as Positive - just in case - and that looked
almost perfect. But the cardboard mounts clearly said Kodachrome!?
Totally confused I took apart one unexposed slide and, sure enough,
the film number is 5073 which is Kodachrome 25 daylight (see P.S.)

Visually, there is no visible red cast on the slides themselves, of
course, just like all other Kodachromes don't have any blue cast when
viewed. However, Nikons "see things" when it comes to Kodachromes. The
only explanation I have is that Kodak messed up the development in
some way. This is not perceptible to the human eye, but nothing
escapes the Nikons. I suppose I should be happy about that but,
somehow, I'm not! ;o)

Back to square one... Again... :-(

Don.

P.S. Speaking of which, a handy link:

http://www.taphilo.com/photo/kodakfilmnumxref.shtml

 

[Don]

And for the online sellers who do not include the film carriers, closely
question the phone folks at B&H or Adorama about availibility BEFORE you
bid because the offerings on their web stores may not truly track
inventory - these two kept me optimistic with back order assurances for
more than four MONTHS!

The same goes for Nikons. LS-50 does not come with a film strip holder
(an absolutely essential item!) and I read they are very hard to come
by. Fortunately, my previous scanner was an LS-30 and back then they
did include a film strip holder as standard.

--- sarcasm on ---

Somebody at Nikon must have goofed big time because, to my surprise,
the LS-30 holder works in the LS-50 as well!

--- sarcasm off ---

Hence my tagline.

Pessimists remain morose precisely because they are too right too often.

No such thing as pessimists. Just realists! ;o)

How does that corollary of Murphy's Law go:

Murphy was an optimist.

Don.

 

[Roger]

The same goes for Nikons. LS-50 does not come with a film strip holder
(an absolutely essential item!) and I read they are very hard to come
by. Fortunately, my previous scanner was an LS-30 and back then they
did include a film strip holder as standard.

LS5000 comes with all you need unless you want the SF210.
Don't back order. With B&H you can be put on a "notify me" list.

I think I purchased mine from B&H. I ordered before they were
generally available and did have to wait a couple of weeks. I'd had a
chance to use one earlier. I don't know where he got it as I couldn't
even find them listed as available, but liked it and ordered one.

I did make sure before ordering that it did contain the film strip and
slide feeder.

I did notice in the literature of many scanners they did not include
the film holder which made no sense. Of course it may have been how
those particular scanners claimed a lower price.

Check the stores on e-bay. Stick with established outlets and call to
make sure they have them in stock. Pay by credit card as you can
cancel. B&H didn't charge my card until the item was shipped.

--- sarcasm on ---

Somebody at Nikon must have goofed big time because, to my surprise,
the LS-30 holder works in the LS-50 as well!

Much of their stuff is interchangeable. The new scanners that use the
SF210 will use the old SF200 and the old ones will work with the new
ones.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

 

[Roger]

LOL.

I lost track how many times I had to restart! Like I said before. I've
done quite a few things in my life but nothing has been so full of
"gotchas" (and so frustrating) like scanning.

Just yesterday I was blind sided by a new "out of left field"
Kodachrome/Nikon trap. I've been going on all cylinders scanning my
Kodachromes (blue cast and all...) when all of a sudden on the latest
film I get a massive red cast!?!? Huh?

Puzzled, I tried scanning as Positive - just in case - and that lookd

Kodachrome is a positive transparency, or it this a case of English Vs
English?<)

almost perfect. But the cardboard mounts clearly said Kodachrome!?
Totally confused I took apart one unexposed slide and, sure enough,
the film number is 5073 which is Kodachrome 25 daylight (see P.S.)

I've never seen a color shift in Kodachrome other than the fading to a
greenish cast.

Ektachrome slides will quite often shift to a deep blue, but that is
from the developing/wash cycle and not the scanner, or at least not
for me... so far.

Visually, there is no visible red cast on the slides themselves, of
course, just like all other Kodachromes don't have any blue cast when
viewed. However, Nikons "see things" when it comes to Kodachromes. The
only explanation I have is that Kodak messed up the development in

I set in quite few rolls to Kodak rather than going through the local
discount store outlet as they were all from the big fly-in at Oshkosh
commendation of D-Day. Nearly all of them were ruined with specs all
over them. I was able to same some but it took me a half hour to hour
of editing to get rid of them. ICE didn't seem to be able to do any
thing about the spots.

some way. This is not perceptible to the human eye, but nothing
escapes the Nikons. I suppose I should be happy about that but,
somehow, I'm not! ;o)

Back to square one... Again... :-(

Don.

P.S. Speaking of which, a handy link:

http://www.taphilo.com/photo/kodakfilmnumxref.shtml

Handy!

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

 

[Don]

Kodachrome is a positive transparency, or it this a case of English Vs
English?<)

Reminds me of a comedian's routine: He reads the lyrics:
You say tomato, I say tomato
You say potato, I say potato
and then looks at the audience and goes:
I don't get it? )

Seriously though (for non-Nikon users) since Nikon has massive
problems with Kodachromes there are two separate settings: "Positive",
for all positive transparencies *except* Kodachromes, and
"Kodachrome", for Kodachrome transparencies *only*.

In terms of scanning both options scan the same way, i.e. they don't
reverse the image. However, the "Kodachrome" option then applies a
profile trying to correct for Nikon's notorious inability to scan
Kodachromes correctly. I say "try" because this profile is woefully
inadequate and the resulting scan has to be edited considerably just
so it looks anything even resembling the original transparency. And
that's before you even start editing in earnest!

I've never seen a color shift in Kodachrome other than the fading to a
greenish cast.

From that, I conclude you don't use a Nikon! ;o) I'm kidding...

Seriously, when scanning Kodachromes on a Nikon there is a disgusting
blue cast plus a severe lack of red. On a slightly underexposed slide
it's quite common to have blue clip like mad while red highlights
barely extend to the middle of the histogram. It's a function of
scanner exposure, but even at absolute exposure of 0, Nikon's
Kodachrome setting doesn't go far enough. The more one boosts exposure
the more disgusting the whole mess looks.

Again, some scans may look OK at first blush but comparing them to the
slide itself it becomes clear there is a definitive blue cast. This
becomes quite apparent when one inspects the histograms.

I set in quite few rolls to Kodak rather than going through the local
discount store outlet as they were all from the big fly-in at Oshkosh
commendation of D-Day. Nearly all of them were ruined with specs all
over them. I was able to same some but it took me a half hour to hour
of editing to get rid of them. ICE didn't seem to be able to do any
thing about the spots.

I get those specs all the time! They're known as "pepper spots" (they
are actually microscopic bubbles in the film base) and are therefore a
function of the film itself. It wasn't until we started scanning that
these pepper spots became a problem. Actually, it wasn't until the
scanner resolution went up to 4000 dpi that they became a problem.
Modern film manufacturing has been modified to eliminate them.

As for ICE, as a rule it doesn't work with Kodachromes because -
unlike chromagenic film emulsions - Kodachromes contain small silver
particles in dark areas (the same thing found in B&W film). Since
infrared light can't penetrate these particles ICE considers them dust
and tries to "correct" them.

Therefore, ICE may work with overexposed Kodachromes where all the
silver has been washed out. Some people claim it works on all
Kodachromes, but that's because they haven't inspected the image
carefully. If one goes to ~300% magnification and compare an ICE scan
to a non-ICE scan (overlay and flip between the two) the artefacts
introduced by ICE are glaringly obvious.

Don.

 

[Don]

LS5000 comes with all you need unless you want the SF210.
Don't back order. With B&H you can be put on a "notify me" list.

In my case the FH-2 (which came with my LS-30) works just fine in the
LS-50. The designated film strip holder for the LS-50, however, is
called FH-3 and it's an "optional extra" according to Nikon. :-/

Much of their stuff is interchangeable. The new scanners that use the
SF210 will use the old SF200 and the old ones will work with the new
ones.

Nikon do fool around with adapters which have an electrical
connection. I remember reading here about one such case where
connecting some points made an allegedly (according to Nikon)
"incompatible" adapter work just fine in a different scanner.

If Kennedy is reading he knows what I'm talking about and may offer
more details.

Don.

 

[Roger]

Reminds me of a comedian's routine: He reads the lyrics:
You say tomato, I say tomato
You say potato, I say potato
and then looks at the audience and goes:
I don't get it? )

Seriously though (for non-Nikon users) since Nikon has massive
problems with Kodachromes there are two separate settings: "Positive",

I just finished up quite a few thousand Kodachrome 25s through a Nikon
LS-5000 and didn't see any problem.

for all positive transparencies *except* Kodachromes, and
"Kodachrome", for Kodachrome transparencies *only*.

In terms of scanning both options scan the same way, i.e. they don't
reverse the image. However, the "Kodachrome" option then applies a
profile trying to correct for Nikon's notorious inability to scan
Kodachromes correctly. I say "try" because this profile is woefully
inadequate and the resulting scan has to be edited considerably just
so it looks anything even resembling the original transparency. And
that's before you even start editing in earnest!

From that, I conclude you don't use a Nikon! ;o) I'm kidding...

Actually it's the only scanner I use on film. <) LS5000-ED

Seriously, when scanning Kodachromes on a Nikon there is a disgusting
blue cast plus a severe lack of red. On a slightly underexposed slide

Again, I've never seen it. Old or poorly processed Ektachromes will
get a deep blue, but I've never see it on scans of Kodachrome 25.

it's quite common to have blue clip like mad while red highlights
barely extend to the middle of the histogram. It's a function of
scanner exposure, but even at absolute exposure of 0, Nikon's
Kodachrome setting doesn't go far enough. The more one boosts exposure
the more disgusting the whole mess looks.

Again, some scans may look OK at first blush but comparing them to the
slide itself it becomes clear there is a definitive blue cast. This

Again, I've never seen this.

becomes quite apparent when one inspects the histograms.


I get those specs all the time! They're known as "pepper spots" (they
are actually microscopic bubbles in the film base) and are therefore a

No, these are a contamination. They are not in the film base.
The only ones I've ever seen were in this particular bunch of rolls
all sent in at the same time. Rolls processed later did not have the
spots.

function of the film itself. It wasn't until we started scanning that
these pepper spots became a problem. Actually, it wasn't until the
scanner resolution went up to 4000 dpi that they became a problem.
Modern film manufacturing has been modified to eliminate them.

You can see these by just holding the slides up to the light, or
putting them in a hand held viewer.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

 

[Don]

I just finished up quite a few thousand Kodachrome 25s through a Nikon
LS-5000 and didn't see any problem.

Well, there may be at least two reasons for that.

One, I only have an LS-50 here. Even though the two scanners are very
similar there are differences. I don't think those differences affect
the reaction to Kodachromes, but I can't say that for a fact. Oh,
wait! I can! When I was wrestling with the LS-30 (before I started
wrestling with the LS-50) I had a long exchange with Nikon and I even
sent in a slide. They scanned it with, the then, just released LS-5000
and the blue cast was still there!

Two, it depends on how "sensitive" you are to this blue cast. Mind you
this is largely a function of the original film. If the film was
perfectly exposed or slightly overexposed then the blue cast is
minimized. It's there all right, and I can spot it across a continent
but it may appear less objectionable. However, once you have to boost
the exposure (to compensate for dense Kodakchrome emulsion) the blue
cast skyrockets.

Again, I've never seen it. Old or poorly processed Ektachromes will
get a deep blue, but I've never see it on scans of Kodachrome 25.

With the above preamble in mind, have you looked at the histograms?

Try flipping between the three channels in Photoshop, for example,
(Control 1, 2, 3 on a PC to toggle the channels). You should see the
peaks "move" increasingly to the right as you go from R to G to B
channels. That's the indication of a blue/green shift.

Also, look at an area you consider neutral and then move the mouse
over it. The color readouts should show the blue value consistently
higher than the other two. Or, if you really want to be exact, use a
cropping tool to select a small area and do a histogram on that.

No, these are a contamination. They are not in the film base.
The only ones I've ever seen were in this particular bunch of rolls
all sent in at the same time. Rolls processed later did not have the
spots.

Oh, I see! That's a different thing then.

You can see these by just holding the slides up to the light, or
putting them in a hand held viewer.

Yes, you can also see them with a magnifier if you look carefully, or
a microscope, but since slides were usually projected this did not
become as much of a problem until we started scanning.

To be fair, you only see the pepper spots on a scan if you magnify the
image to 100% or more. Even without editing, they usually disappear if
the image is reduced in size and converted to JPG which, I suppose,
would be the modern equivalent of a projection.

Don.