Do conductors scores ("partitur") ever differ greatly from the full score?

Question

I believe most conductor’s scores are full scores, with all instruments appearing on them in a prescribed order, in the same notation the player will see

However, it seems like there would be occasions when the full score is not ideal in some way. Perhaps in cases of polymeter/polytonality and other complexities/ambiguities, it may be easier for the conductor to transpose or change the meter of some parts. I suppose maybe also the score might be customised by the conductor based on different players performance.

In such cases (or any others too), do conductors highly customise the full score?

Do some conductors have drastically differing partitur for the same piece?

Answer 1

There are often various scores for a piece that conductors can choose from:

• a full score with a system for each instrument, even it they are not playing. Generally several similar instruments (e.g two flutes) will be combined on one system. Normally transposing instruments are transposed in the score, but sometimes they are in concert pitch in the score (except for octave-transposing instrument like piccolo or contrabass). This needs to have exactly the same rhythmic information the players have.
• sometimes the full score is optimised: if a longer section involves only a few instruments, other systems will be left out to save pages.
  This is an example (the beginning of Wagner's Siegfried):
• sometimes a 'condensed' score is used that has two or three lines containing all the important musical information. The is common for band music.
  An example:
• a 'piano conductor' score is like a condensed score but designed for a conductor who is conducting from the piano (often found in older musicals).
• sometimes a conductor might even conduct from a piano reduction of the score.

In any case the conductor will usually enter a lot of markings to make sure they don't miss any anything important.
This is an excerpt from Leonard Bernstein's marked up score for Mahler's First Symphony (of course another conductor would use totally different markings):

Answer 2

In such cases (or any others too), do conductors highly customise the full score?

Conductors do not typically produce the score. This is done by the publisher, or, for a new work, the composer or a professional copyist. As noted in the other answer, the conductor typically makes notes in the score, but it's not usually possible to modify the grouping of multiple instruments on one staff, for example.

Older works may be available in multiple different editions in which editors have made different choices about how to present the piece. For such works a conductor may choose a particular edition based perhaps on choices such as that. But even so, most editions will follow the practice reflected in the composer's manuscript. Generally, composers and editors all follow standard conventions, and deviating from them would not generally have a lot of benefit.

In the present day, with computerized music notation, it is somewhat easier for a conductor to produce a customized full score or even a complete set of performance materials. But it is still a huge job, and most conductors won't be likely to do it. Furthermore, for works protected by copyright, the conductor would need permission to do so, which might be denied.

it may be easier for the conductor to transpose or change the meter of some parts.

This is tantamount to sacrilege in classical music (except for renaissance and earlier music, as note values have been inflated over the centuries and there have been other significant changes in rhythmic and metrical notation). But if a conductor wanted to do this, it would be necessary not only to change the score but also to change all the performing parts. Otherwise it would be too confusing to try to communicate with the orchestra during rehearsals, because the conductor would have to remember to translate from the meter in the full score to the meter in the players' parts.