I spent some time yesterday comparing results on the new NY marriage indexes on Ancestry and the marriages records on the website for the Rochester Municipal Archives. NY State passed a vital records law in 1880 that said records should be sent to Albany. Compliance by some small communities was spotty until 1900. Rochester had started recording marriage records in 1876 and those early records can be found on the Rochester Archives website.
The indexes on Ancestry start in 1881 and I took 40 marriages that were in the Archives records and looked to see how many were on Ancestry. I only found one of the 40 on Ancestry. Even on that one record they disagree on the bride’s first name. The NY State Index on Ancestry have her as Rosa and the Rochester Archives have her name as Rosalia (see image).
I then checked marriages from 1882. Of the 20 names found on the Rochester Archives only 13 were found on Ancestry. Another search for marriages from 1904 came up with 8 out 10.
On Ancestry the 1882 marriage of Louis Wolohan showed two brides; Etta Smith and Sarah A. Martin. When I looked at the image of the index page, it turns out that Ancestry had the wrong certificate number for Sarah A. Martin. That ended up linking her to the wrong husband.
The marriage of Albert Greenhalgh and L. Smith is recorded in the Rochester Archives as taking place in 1987 even though their records don’t go up that far. On Ancestry I found that marriage actually took place in 1866. There were a few other similar errors in the Rochester Archives records. Any transcription of records is going to have errors but Ancestry has more transcription errors than the Rochester Archives.