Perf marks on hand processed negative - Morse G3 Tank

[Derick Crucius]

Does anyone happen to use the Morse rewind tank? Every roll i process in the thing always ends up having perf marks throughout the whole roll on the perforation side. Has anyone else experienced this? What could be the the cause?

 

-Derick

[Martin Baumgarten]

Hi Derrick. This is a common processing artifact due to the nature of the rewind process. Small amounts of chemistry get trapped in the perforation areas and while the film is wound upon itself, those tiny pockets have more chemistry in them than what rests in the emulsion itself, so they are more active. This extra energy creates a ghost image of the perforation which is visible after processing is complete. There isn't any way to avoid this other than using a full immersion type of processing method (rack & tray, spiral reel, drum in tank etc). It doesn't hurt anything and isn't visible in the image, unless you're shooting in Ultra 16mm where part of the image protrudes into the area between the perforations. If so, then you will need to use another processing method.

Hope this helps.

[Derick Crucius]

Hi Derrick. This is a common processing artifact due to the nature of the rewind process. Small amounts of chemistry get trapped in the perforation areas and while the film is wound upon itself, those tiny pockets have more chemistry in them than what rests in the emulsion itself, so they are more active. This extra energy creates a ghost image of the perforation which is visible after processing is complete. There isn't any way to avoid this other than using a full immersion type of processing method (rack & tray, spiral reel, drum in tank etc). It doesn't hurt anything and isn't visible in the image, unless you're shooting in Ultra 16mm where part of the image protrudes into the area between the perforations. If so, then you will need to use another processing method.

Hope this helps.

Ahh wonderful! Thank you so much for the insight, Martin. Its very much appreciated. I'm fine with the perf markings as long as they don't bleed into my image. Good to know!