Negative deterioration

<p>Hello,<br>

Is there any obvious explanation for what's causing the deterioration shown in the images bellow?<br /><br />These are Ilford Delta 100 120 format. I have had them stored in a cool and dry place (not in the fridge though). I am currently based in Cape Verde and have the films developed in Germany (I have them sent by post). I have had other rolls of the same batch of film developed in the same lab before and didn't have these patterns.<br>

<img src="http://www.koiastudio.com/04-120-096-2015-011.jpg" alt="" /><br>

<img src="http://www.koiastudio.com/04-120-096-2015-012.jpg" alt="" /><br>

Thanks for any help/advise.</p>

Did the images come back from lab that way or deteriorate after processing?

<p>To me that looks like humidity damage to the emulsion before exposure and processing. Did you keep the rolls in the foil packages until you loaded them in the camera?<br>

If you have another unexposed roll stored in the same conditions, just unroll it and look and see if the emulsion side is blotchy.<br>

It might also be fungus, but that normally looks "thready". Look at the emulsion side of the film by reflected light and see if you see something growing there.</p>

 

<p>Sorry for my use of the term "deterioration". It wasn't the most accurate word to use! :p<br /><br /> @Mike Gammill: The negatives arrived like this from the lab.<br /><br /> @John Shriver: That was also my hunch. Although I kept them inside the foil, it can get pretty humid in Cape Verde. I don't have any other Delta films, but I will take a look at other rolls I had stored in the same conditions.<br /> I have also had problems with fungus before (on my lenses). Do you mean I should look for fungus also on the unexposed roll? I don't see anything growing on these developed rolls.<br /><br />Thank you so much for your inputs and advises.</p>