Imperial Stout Extract Kit - Contamination?

Extract/Partial Mash Brewing
1

I transferred the imperial stout from the primary to the secondary. When I went to rack it from the primary, I noticed a tihn layer of white stuff across the top. It was in the primary for about 6 weeks (directions only called for 4). Not sure if that is supposed to be there or not (first time making an imperial stout). I used Wyeast 1728 Scottish Ale Yeast. Is this a normal byproduct of the long fermentation process? It has been in the secondary for about two weeks and again has that white layer across the top. I’m just wondering if that is normal for this style of if something contaminated my batch. I sanitize like crazy and have never skunked a batch before.

Thanks for any input.

Crypto

2

Pic? Hard to tell with out one. Goole infected home brew see if it matches

3

Here’s one, not a good shot though.

4

Could be C02 bubbles. They can be so tiny and cling together to resemble a film.