Icaillo,
Your response is correct but I'll give more details:
There are numerous types of 'restorations'. There is a restoration on film alone.
There is a restoration where they used digital programs to correct problems and then
out-put it back to film. Finally there is a restoration where elements were corrected
only for the latest DVD or Blu-Ray release but no film element was out-putted for the
future which means they will have to start from scratch if they do another transfer at
a later date.
I'll take them case by case.
FILM RESTORATION/PRESERVATION:
This is a photo chemical restoration. Current movies don't require it for the time being
because they are photographed on 'low fade' color negative stock (aka Eastmancolor).
Distributors make back up preservation elements which includes a color interpositive (fine
grain fully color corrected positive) and black and white separations of each color to restore
it 50-100 years from now when or if the original color negative fades. Films shot with color
negatives made between the years 1952-1982 will require restoration because that film stock
was unstable and faded. The extent of which depends on the original processing and storage.
To restore a faded Eastmancolor negative means to make a new color corrected print and with
any luck, the original color balance can be retained. Then they make a new low fade color
interpositive (fine grain) for the future. Or, they can use the black and white color separations
to make a new color internegative which will contain the correct balance but be two generations
removed from the camera negative.
In terms of making a video master from film elements...
The best quality is to master a film directly from the original camera negative, color correcting it
and reversing the image to a positive. However, that is quite expensive because of the shot
by shot color correction necessary which takes up many studio hours. It took 14 hours to do
this for my new feature.
The second best quality is to master a film from a color interpositive which is a fully color corrected
fine grain color print. Not good for projection in a theater but good for a video transfer. The advantage is you only have to adjust the overall contrast and saturation since the film is already
color corrected on a shot to shot and scene to scene basis. The only problem is you add a little bit
more grain since film is an analog format and each generation removed from the camera negative
adds some grain to the image. Not objectionable in most cases but when you see a camera negative
transfer like the Connery Bond films, you do notice the difference. Camera negatives are the actual
generation of what was exposed in the camera. A color interpositive is a first generation print.
Mastering a movie from a color interpositive is less expensive and can be done in a few hours.
In Warner Brothers 'ultra-resolution' transfers used for films like "The Searchers", what they did
was the transfer the black and white separations of each color to a separate tape and then
add the color and recombine them. The reason they did this was because the separations were
already first generation and if they made a color internegative from them (necessarily to make
prints) and tried to tape that it would be third generation. Video transfer mastered in this
manner from first generation black and white separations can look very good too but once again
the best quality is still from the color negative if it still exists and if it's not faded beyond usage.
Unfortunately, in the case of many fifties' Eastmancolor negatives that is the case so they must
go from whatever elements still exist that have the color. Master a film from black and white
separations and then recombining them is very expensive. Each reel has to be transferred separtately.
Then they have to be combined and then they have to be color corrected. It could take weeks of
studio time.
VIDEO RESTORATION:
Keeping the above elements in mind and with the same quality considerations...sometimes
either the camera negative or the color interpositives or the black and white separations have
damage on them. Scratches, tears, printed in dust and dirt, flickering and flashing from bad
lab work and other problems. So after they tape one of the three elements (camera negative,
color interpositive, black and white seps) they need to do a frame by frame correction to remove
the most obvious defects. It's easy to paint out dust and dirt and very difficult to fix deep scratches or breaks but it can be done...at great expense. In extreme cases like "The Robe", there was no single film element
that didn't have problems so Fox had to tape the camera negative, black and white separations and
color interpositive then go through the entire film on a shot by shot basis and pick the best footage
for the final video master. Astronomically expensive and could take months of studio lab time.
For video masters there are different resolutions available. 2K was used initially but it really wasn't good enough.
Today 4K is the standard although "The Wizard of Oz" was recently done at 8K.
From the new corrected digital video master they can bump it down to Blu Ray and standard
definition DVDs for consumer use. The smartest distributors with long range vision will also
out-put a new 35mm color internegative from the digital master
for the future so they don't have to start from scratch again later. Just re-master the restored
new 35mm negative which will take very little studio time. Fox did output a new restored 35mm color
internegative of "The Robe" so theatrical prints could be struck and of course they could re-master the
film from the new negative years from now as required.
For black and white movies, two basic elements are used.
If the 35mm negative still exists then that is the best element to master from although they
need to do a shot by shot contrast correction. For many if not most pre-1950 movies shot
on the dangerous and volatile nitrate stock, what exists now is a safety fine grain print which
is good but not as razor sharp or fine grain as the original black and white original negative.
The same applies regarding printed in damage and wear. They might have to tape the fine grain
master (first generation fine grain print) and do digital fixes for the dust, dirt, wear and scratches.
Unfortunately, this isn't as common for black and white classics as it is for color films. While titles
like "A Christmas Carol" have gone through a full digital clean up, most of the Abbott and Costello
movies still have printed in minor dust and scratches in sections on the fine grain masters they
used for the transfers. Perhaps Universal will fix them for Blu-Ray some day, especially their best
movie, "Abbott and Costello Meet Frankenstein", which has more wear than the others because
it was so popular and re-issued so often.
Silent films pose a real problem. Only in very rare cases do the nitrate negatives exist (i.e. "Metropolis") and even when they do, they are very worn since they had no duplicate
negative stock in that era and every release copy was struck from the original which damaged
them. Harold Lloyd and Charlie Chaplin made fine grain master prints from their nitrate negatives
although even there, a lot of damage was printed into the preservation elements. They did a full
digital clean up on some select Chaplin movies like "City Lights". In most cases all that exists
on an old silent film is a very worn and splicey original nitrate print. While it's possible to clean
them up and make them look good (but not great because theatrical release prints are too dark
for optimum video transfers), they rarely do because most are in the public domain and there would
be no way to recoup the costs. In other cases all they have is a dupe negative made from the
battered old print on safety film. These look really bad because making a negative from an old
scratchy print made the new copy lose details and get too contrasty and dark.
Here is a simpler list of what's best for video restorations:
1) Original camera negative in color or black and white. This also applies to three strip Technicolor
films where they can tape each separate color (filmed in black and white) and superimpose
them on the digital master. However, they will have to have a shot to shot correction which
is expensive and takes up lots of studio hours.
2) A fine grain color interpositive or fine grain black and white master. Good results but one
generation removed from the camera negative. The advantage is the image has been corrected
and all they have to do is an overall contrast and brightness adjustment. No shot to shot correction
is required and it doesn't take up too much time in the studio.
3) A color internegative or black and white duplicate negative used for theatrical prints. These
elements are second generation which will increase grain and lose some resolution so they
should not be used for video master unless the other elements are missing or too damaged
to use. It won't take up much studio time because it's color corrected but the added grain
might be objectionable.
4) A color or black and white release prints does not generate good video masters and should
be avoided unless that's the only thing that exists on the movie. A theatrical release print
is high contrast which works fine with a projector but is not good for video which requires
low contrast materials that can be adjusted so they have the proper contrast and brightness
for video. Too much detail is lost when videotaping theatrical prints.
Moviefanatic,
Not sure what your friend meant other than whatever you watch will always be a positive
image whether it's on video or in a theater. However in the case of some DVDs, while the image
is positive it was mastered directly from the camera negative. When they did the transfer they
reversed the negative image to a positive.
You can joke with him that sometimes a 'double negative' isn't bad grammer since
that's what you watch when you see a 3-D film which has two separate images superimposed
on screen.
