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b. 15

composition: Op. 28 No. 18, Prelude in F minor

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In A there is no  before the top note of the L.H. chord on the 4th beat of the bar. The patent inaccuracy was already corrected in FC (→GE) and FE (→EE).

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , FE revisions , Fontana's revisions , Inaccuracies in A

b. 15

composition: Op. 28 No. 18, Prelude in F minor

2 slurs in A (→FE,FCGE) & EE2

No slurs in EE1

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The slurs were certainly overlooked in EE1, which was corrected in EE2.

category imprint: Differences between sources

issues: EE revisions , Errors in EE

b. 15

composition: Op. 28 No. 18, Prelude in F minor

R.H. wedges in A

4 staccato dots in FC (→GE) & EE

3 dots in FE

4 wedges suggested by the editors

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In this bar Chopin again marked the articulation of the chords only over the R.H. part. As the performance cannot differ from the one in b. 13-14, in the main text we add marks also under the L.H. chords. Such a solution was adopted both by FC (→GE) and FE (→EE).
In FE, the missing mark for the 1st R.H. chord must be an oversight of the engraver.
Both FC (→GE) and FE (→EE) interpreted the marks of A as staccato dots. Although they are not as pronounced as those in b. 9-12 or 14 (the R.H. mark), we consider them to be wedges.

category imprint: Graphic ambiguousness; Differences between sources; Editorial revisions

issues: EE revisions , Errors in FE , Inaccuracies in FE , Wedges , Inaccuracies in FC

b. 16

composition: Op. 28 No. 18, Prelude in F minor

Short accents in A (→FE,FCGE)

Vertical accents in EE

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Vertical accents were often used in EE as an arbitrary replacement for authentic horizontal accents (short or long) – cf., e.g. the Prelude in G minor no. 12, b. 37-38.

category imprint: Differences between sources

issues: EE revisions

b. 16-17

composition: Op. 28 No. 18, Prelude in F minor

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In A entire b. 16 and the 1st R.H. quaver in b. 17 were first written in an earlier version: . Chopin then crossed them out entirely and entered the final text, although not without hesitation (mistakes?) – in the later version the 6th R.H. quaver was initially written down in the original version (d2-d3), while at the beginning of b. 17 there was most probably an f1-a1-d2-fchord.
See also the note in b. 17.

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Main-line changes