Old Glass Plates - sudden fogged

[SMBooth]

I have been given some old glass plate, Kodak aerial plotting plates in fact which are 9.5 inch square. Circa 1985, been storage in brick garage. All the boxes are sealed, the first plate i taped to the back of my 8x10 and exposed it around ISO 1.5 and all seemed good, very little to no fog, exposure seem OK. To test further I cut some plate down to 5x4 and put in some MPP glass double darks but suddenly the plates appear to be fogged. Question is do plate sudden go off when exposed to air?
Maybe i took to long cutting and they fogged under safe light (ilford 915)

Just pop this question here while I do so more testing.

Thanks

 

[E. von Hoegh]

The "safe" light fogged them, probably.
Panchromatic film cannot be exposed to light of any color.

 

[SMBooth]

The plates are orthochromatic , but Im thinking that they spent too long in the red zone.

 

[Mick Fagan]

Shane, I have an Ilford 906 lso Dark red for use with: Orthochromatic materials and recording paper. (it is certainly quite dark, start eating carrots)

It is 8x10".

Wish to borrow it?

I also have a Kodak unit for Orthocromatic stuff, but it is a lighter colour than the Ilford unit; I would use the Ilford one anyday over the Kodak one I have.

I'm not 100% sure, but I think I also have either an Ilford or a Kodak very dark green, which is for all panchromatic materials.. That said, it really is dark and with young eyes you eventually can see things, it is pretty hard to use and extreme care and the shortest time of exposure, but.......

Mick.

 

[SMBooth]

Hi Mick,
I might try to take you up on that 906, even just to see. It will fit into my safelight.

 

[Mick Fagan]

No worries Shane, give me a hoy.

Mick.

 

[SMBooth]

Mick, surprisingly i don't have your contact detail, can you PM them here and I'll give you a call. I was down your way yesterday too.....

 

[SMBooth]

 

[Mick Fagan]

Looking good, how dark was the 906 filter with your young(ish) eyes?

Mick.