Many are familiar with the Reformed and Roman Catholic baptism index collections at FamilySearch.org, however not all are aware that there is further beneficial information on these indexes other than the genealogical content. The indexes include source material to aid in viewing the actual image. In this article, I will explain the process in locating the digitized images for these baptisms and I will be using my 2x-great-grandfather's baptism index as an example. [All images to the right can be clicked for further enlarging.]
On the right side of the index, you will see what is listed as the "GS Film number". "GS" stands for Genealogical Society, which is otherwise known as the Family History Library in Salt Lake City, Utah. Take the newly-found microfilm number and search for it in the microfilm catalog at FamilySearch.org. This search will result in the exact catalog title being found; click on that title and continue onward to review what is available for that collection.
You can see from the Film Notes, on the catalog title, that the required microfilm number for viewing is the third on the list. The camera icon to the right indicates that the microfilm has been digitized and is available for viewing. Click on that camera icon to pull up the digitized content. Be advised: you may need to be signed-in with your free FamilySearch.org account for the images to load properly.
Now going back to the baptism index, you'll see a section that states "Image Number" and "Line Number". Input that image number into the top left area of the digitized records, as seen on the image to the right, and then navigate to the correct line number. (Note: the line number is not always provided, depending on the time period and whether there was an actual entry number on the document.) While viewing the digitized record, you can verify the information that was provided on the index for inaccuracies, as well as glean all other information not provided on the index (there's a lot!). As you can see in this record example, they incorrectly indexed the mother's name as Zsuzsána Kabai (one entry below), when it's actually Zsuzsána Gulyás.