Get old values in SQL log ( *.ldf file)

See more:

SQL

SQL-Server

'm trying to read the LOG file using the sql command fn_dblog based in one sequence of numbers ( LSN )

Select * from fn_dblog('00000203:00000085:0002','000000204:00000136:0010')

BUt, when I execute that command, I got an error, saying that the code is invalid... I did some studies based on this site[^] about LSN and log files... but, or I got an error, or, when I execute the command with the two NULL parameters, I just got 2 rows of informations... I considerate that is intresting, because, when I use a program to read the data-log, I got all the information's.

How I can make to read all OLD data and information of log using SQL, to compare with new information in database ?
I know, have some programs make that, like ApexSQL LOG and mdfview, but, I want to know, how to make this in SQL or, how I can make this in C#.

If you see in picture, that program return the new and old information, after update in row.
Image[^]

So, that program get the information from *_LOG.ldf file and compare with *.mdf file to show the new and old value.
I tryed this[^] too... but, the first SELECT return nothing...

So, how I can make to read that informations, old and new information from database ? ( the most important is the old information, for I can compare the data )

Thanks.