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Blue Pressure Fogs

Published : 5th March 2004

Has anyone encountered Blue Pressure Fogs?

Series that I'm operating on is having some intermittent Blue Pressure Fogs on both A and B cameras (SR3 Advanced's). This has now happened three times with thee different mags and seems to be in the last 100 feet for only one or two takes all towards the Fixed guide side of the frame (Screen Left so Camera Right)

Anyone know what the layer order is so we can figure out how deep scratches are?

Anyone, Anyone?

Thanks

Eric Fletcher SOC
Steadicam/"A" Camera Operator
Los Angeles, CA USA

Eric Fletcher SOC wrote :

>...Series that I'm operating on is having some intermittnt Blue Pressure >Fogs on both A and B cameras (SR3 Advanced's)...

The only thing we have noticed is several blue vertical scratches near centre frame on the transfers. We haven't had time to inspect the neg. In a couple of instance the scratches appeared only for a few seconds near the end of the roll. In other cases they were within the roll, appeared for a few seconds, then disappeared. Two different mags, SRII R16.

Wade K. Ramsey, DP
Dept. of Cinema & Video Production
Bob Jones University
Greenville, SC 29614

>Anyone know what the layer order is so we can figure out how deep >scratches are?

Fog? Pressure fog? or scratches? Which are we talking about?

All negative stocks have the blue-sensitive yellow dye layer at the top. Pressure fogging will cause yellow marks on the negative, blue in the positive image. Pre-dev scratches in the supercoat (above the dye layers) will also cause pressure fog. If the scratches go right through to the emulsion layers and remove the top layer you would expect to see blue in the negative, yellow in the positive image.

Dominic Case
Atlab Australia

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