I understand that turning on 'recordPreImages' is required in order to get a copy of a document which is removed from a collection as part of a change stream for a given collection. What I would like to suggest is to add an option that can be set to ONLY capture pre-change images for 'remove' events.

Basically, for my particular use case, the only time I need access to the 'pre image' is on delete (so I can do some post-processing for which I need to know what some of the attributes of the document were prior to it being removed).

Other than that, for update operations, for example, I could piece that info together from the change record and by re-querying the item or by looking at the fullDocument attribute of the change record.

It seems that having to suffer the performance penalty of capturing pre-change images for every change event just in order to have a pre-removal image of the document when the relatively infrequent 'remove' events happen is an unnecessary burden.

While having the option to ALWAYS capture pre-change images is useful and there are use cases where that would be desirable, I think it would also be VERY useful to offer the alternative I allude to herein.