Is my cider infected ?

[Newbrewer1]

Second attempt at a basic cider
I’m wondering if it maybe infected now

So my recipe was
4.5l of apple juice (no preservative)
Wine yeast
9oz of sugar

After 4 weeks racked into a secondary demijohn and topped up with a bit extra apple juice
So started fermenting again
I was planning on bottling in 2 weeks time (I think the fermentation will have stopped then)

All Around the top of the demijohn there is a white patchy film on the glass
It doesn’t look like it’s coming from the cider liquid itself, the cider looks fine

Could this be an infection? or could it just be some dried cider/juice on the glass ?
Should I throw in a Camden tablet and just bottle now
Maybe not as dry as I would like but if it saves it then worth it?

Difficult to see on pics

Any advice I would appreciate

 

[crowcrow]

Can you attach a photo (not sure if new accounts can?) - I don't brew cider, but get all sorts of films and white stuff in my beer and turns out fine.