How light-tight are the foil film packages.

[jonathan_lipkin]

I accidentially opened the changing back before I closed a fifty-sheet box of portra. The top ten sheets are gone, obviously. There is also a sealed foil pouch with the remaining twenty five sheets. Is this light-tight? Is the film OK or did I kill the whole box??

[Mark Sampson]

You should be ok- but shoot 1 holder as a test. The foil packets are NOT light-tight in bright light, or for long periods in room light.

[jonathan_lipkin]

Nah, was just a few secs, room illuminated by dim daylight, took a sec after the "oh ##$%" realization.

[Jack Dahlgren]

I accidentially opened the changing back before I closed a fifty-sheet box of portra. The top ten sheets are gone, obviously. There is also a sealed foil pouch with the remaining twenty five sheets. Is this light-tight? Is the film OK or did I kill the whole box??

I wouldn't be so sure about the top ten sheets either. With anti-halation coating and stacked neatly in a box, you might not have done much damage.

[lenser]

I can't say that I'm expert, but I routinely open my new 4x5 boxes in room light and set everything up to load the holders. The packets are nested in the boxes and open to the moderate brightness. So far, never a fogged sheet.

I don't think I would be as confident in bright sunlight,.

[eddie]

but I routinely open my new 4x5 boxes in room light and set everything up to load the holders.

why do that? opening the box in the tent (darkness is very easy). i would NEVER intentionally open a box of film in the light no matter is it is new or old. NEVER!

i have done what the OP has done. usually the 1st few sheets are exposed and then on down the package the edges are exposed......if the pile was perfectly stacked less of a problem....but usually it is not perfectly stacked and it goes pretty far down.

with the price of color developing i would not bother shooting the rest of the opened pack......it always seems to work out that my bets shot was the one with the most fog. murphy's law. the unopened pack should be fine.

eddie

[Robert Hughes]

I routinely open my new 4x5 boxes in room light and set everything up to load the holders...So far, never a fogged sheet.
I routinely jaywalk in traffic without looking first. So far, I've never had a problem ... :)

[rguinter]

I agree with eddie.

My procedure is to slit one end-tape on a new box of film carefully before putting the box into my changing tent. then I close everything up with holders, etc. inside as needed for whatever I'm loading.

Once inside, the nested boxes can be opened with the outer two boxes (still connected with one end-tape) put aside as a complete unit.

Then I have only a single inner box and the film in foil-pouches to deal with by feel.

As with eddie's comments, I think opening up everything beforehand in the room-light is an iffy procedure at best.

My opinion. Bob G.