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b. 26

composition: Op. 25 No 8, Etude in D♭ major

..

In EE1 there is no  before g2, which in this context has to be considered as a mistake (admittedly an oversight).

category imprint: Differences between sources

issues: EE revisions , Cautionary accidentals , EE inaccuracies

b. 27-28

composition: Op. 25 No 8, Etude in D♭ major

No fingering in A (→GE) & EE1

Fingering in FE

Fingering writteninto FED

..

Chopin added the fingering of the bottom voice most probably at the time of proofreading FE (also in bars 28 and 29). What draws attention is the fact that the composer considered the fingering of the top voice to be obvious – cf. the Etude in Gminor, No. 6, bars 14-15. The entry in FED proves that what was obvious to Chopin was not that obvious even for such a talented pupil as Miss O'Meara.

category imprint: Differences between sources

issues: Annotations in teaching copies , EE revisions , Annotations in FED , Authentic corrections of FE

b. 27

composition: Op. 25 No 8, Etude in D♭ major

No sign in A

 in FE

 in GE

 in EE

Our variant suggestion

..

Same as in bars 19-20, in A there is no  asterisk. In this kind of context, indicating the clear place of the pedal's release poses certain problems, as obtaining the correct sound effect requires a gradual pedal's release. In the main text we suggest the signs given in FE and EE in a variant form, as being probably authentic.

category imprint: Differences between sources

issues: GE revisions , No pedal release mark

b. 28

composition: Op. 25 No 8, Etude in D♭ major

in A (→GE) & EE1

No marking in FE & EE2 (→EE3)

in FED

..

The dynamic indications of the final part of the Etude were almost certainly added by Chopin to the three, generally finished, Stichvorlage manuscripts. In bars 28-31, EE1 transferred the most elaborately developed version with  in bar 28 and diminuendo in bars 30-31, A (→GE) includes only , while FE, devoid of indications, remained in the shape preceding the additions. Circa 10 years after the publication of the Etudes, Chopin added here  in a pupil's copy (FED), which, according to us, is to be considered as an alternative dynamic concept and not a conclusive change.
Deletion of  in EE2 (→EE3) is most probably related to the addition of fingering after FE.   

category imprint: Differences between sources; Corrections & alterations

issues: Annotations in teaching copies , Annotations in FED , Authentic post-publication changes and variants

b. 28

composition: Op. 25 No 8, Etude in D♭ major

No fingering in A (→GE) & EE1

Fingering in FE

Fingering in EE2 (→EE3)

..

The fingering of the beginning of the phrase was added by Chopin most probably at the time of proofreading FE. It was then repeated – with errors – in EE2 (→EE3). 

category imprint: Differences between sources; Corrections & alterations

issues: EE revisions , Errors in EE , Authentic corrections of FE