How a Lab Process the NEG?

narke wrote:
 > Hi,
 >
 > I am planing to do some print films (I did slides before). I know that
 > a lab has great number of stops on the latitude of exposure, so I get
 > some questions around this and desir to get help from you.

Actually the lab doesn't the film does.... You talking colour or Black
& White? In colour the lab typically goes by the time/temperature
method for an entire run, which depending on the equipment could be a
single roll, or could be a dozen rolls. Only the lab can tell you
whether push processing in possible with their equipment.

 > 1) For a negative, a lab may print it lighter or darker. My question is
 > that whether this kind of departure is persistent on a whole roll? Say,
 > I has 3 exposures at the EV of EV a, EV a-1, EV a+1 perspectively, what
 > would be the final result on the prints? Would I get three prints in 3
 > different brigtness level?

Most lab printers, will easily balance for a stop or two, much beyond
that though, and there will be colour shifts with colour, black and
white can block up the highlights or shadows, depending on the
difference. Any lab that can't compensate for 1 stop, should not be used.

 > 2) If I do not print the negatives and only have the lab develop them.
 > Can I keep my ideal of exposure? Actually, I want to know whether the
 > departure of processing happens on the develop phase. If not, I get a
 > choice to scan the negatives by myself.

Yes, however scanning negatives can reduce the latitude, and can
introduce colour shifts on it's own. You may need to adjust the scanner
software to compensate.

W<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: How a Lab Process the NEG? 

"narke" <steven.TakeThisOut@lczmsoft.com> wrote in message
news:1107168130.556091.272630@z14g2000cwz.googlegroups.com...
 > Hi,
 >
 > I am planing to do some print films (I did slides before). I know that
 > a lab has great number of stops on the latitude of exposure, so I get
 > some questions around this and desir to get help from you.

The exposure latitude is a function of the film, not the lab. Generally,
print film has more latitude than slide film.

 >
 > 1) For a negative, a lab may print it lighter or darker. My question is
 > that whether this kind of departure is persistent on a whole roll? Say,
 > I has 3 exposures at the EV of EV a, EV a-1, EV a+1 perspectively, what
 > would be the final result on the prints? Would I get three prints in 3
 > different brigtness level?

Depending on the equipment the lab uses, it will probably attempt to get the
best possible print from each of your three exposures. However, you may
notice a difference between the pictures, particularly in shadows and/or
highlights. If you prefer the EV a-1 (or EV a+1), then that is the exposure
you should _probably_ use for that film when processed by that lab (on that
particular day and hour, using the particular printer/processor
machine/operator and chemical balance!) In other words, I wouldn't sweat
plus or minus one stop too much.

 >
 > 2) If I do not print the negatives and only have the lab develop them.
 > Can I keep my ideal of exposure? Actually, I want to know whether the
 > departure of processing happens on the develop phase. If not, I get a
 > choice to scan the negatives by myself.

If the lab maintains their chemical balance properly, a roll of negatives
developed today should match a roll developed a month from now. It's when
the negs are printed that the (human) variations could take place. You could
possibly ask the lab manager to show you their C-41 "plots" for today and
last week. If they pull out a notebook full of graphs and all the graphs
look similar, that's good. If they give you a puzzled look, leave!

Ken Hart<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: How a Lab Process the NEG? 

Most wholesale lab printers will adjust each image to produce the best
possible print trying to make the order consistent. (IE it has slope
adjustments for under exposed and overexposed negs.) the Agfa printers have
base scanning where the printer scans the film determines the film base
correction and applies it when printing this way it only needs 1 film
channel for all film types. This allows the printers to print at speeds over
15,000 prints per hour some printers print as high as 22,000 prints per
hour.

Photobossman


"Ken Hart" <kwhart DeleteThis @aec.nu> wrote in message
news:ctos7p$23f$1@news.chatlink.com...
 >
 > "narke" <steven DeleteThis @lczmsoft.com> wrote in message
 > news:1107168130.556091.272630@z14g2000cwz.googlegroups.com...
  >> Hi,
  >>
  >> I am planing to do some print films (I did slides before). I know that
  >> a lab has great number of stops on the latitude of exposure, so I get
  >> some questions around this and desir to get help from you.
 >
 > The exposure latitude is a function of the film, not the lab. Generally,
 > print film has more latitude than slide film.
 >
  >>
  >> 1) For a negative, a lab may print it lighter or darker. My question is
  >> that whether this kind of departure is persistent on a whole roll? Say,
  >> I has 3 exposures at the EV of EV a, EV a-1, EV a+1 perspectively, what
  >> would be the final result on the prints? Would I get three prints in 3
  >> different brigtness level?
 >
 > Depending on the equipment the lab uses, it will probably attempt to get
 > the
 > best possible print from each of your three exposures. However, you may
 > notice a difference between the pictures, particularly in shadows and/or
 > highlights. If you prefer the EV a-1 (or EV a+1), then that is the
 > exposure
 > you should _probably_ use for that film when processed by that lab (on
 > that
 > particular day and hour, using the particular printer/processor
 > machine/operator and chemical balance!) In other words, I wouldn't sweat
 > plus or minus one stop too much.
 >
  >>
  >> 2) If I do not print the negatives and only have the lab develop them.
  >> Can I keep my ideal of exposure? Actually, I want to know whether the
  >> departure of processing happens on the develop phase. If not, I get a
  >> choice to scan the negatives by myself.
 >
 > If the lab maintains their chemical balance properly, a roll of negatives
 > developed today should match a roll developed a month from now. It's when
 > the negs are printed that the (human) variations could take place. You
 > could
 > possibly ask the lab manager to show you their C-41 "plots" for today and
 > last week. If they pull out a notebook full of graphs and all the graphs
 > look similar, that's good. If they give you a puzzled look, leave!
 >
 > Ken Hart
 >
 ><!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: How a Lab Process the NEG?