Life of film 120 vs 135

Hi all.

I've just recieved a pile of film from Silverprint, (FP4 and D3200) where the expiry on the 120 film is around mid 2009. This matches previouse 120 HP5 film, which has always had about 20 months or so until expiry.

However all of the FP4 and HP5 film I have purchaced in the last few months, has had an expiry of around 2011, seemingly twice as long as the roll film.

Is 120 film shorter lived than 135, or have I been consistently recieving 2 year old 120 film. Is this because the metal cartridge for 135 film provides better protection for the film?

I've only ordered from silverprint and 7dayshop previously, so I find it hard to believe that either of them have such common films sitting on the shelf for 2 years, as they would need mightily big shelves.

Geoff

The 120 might be older stock.

Just put the stuff in the fridge and don't worry about it.

I am about to shoot some Agfapan 100 that expired in 1985.

Last night I shot a sheet of 4x5 T-Max 100 with a 1995 expiry. It had been stored for room temperature for most of the time. Base fog was negligible, and the exposure index was slightly lower than metered. Image quality seems good, but it hasn't been printed yet. T-Max 3200 doesn't keep well. Tech Pan seemed to last forever.

Ilford no doubt sells a lot more 35mm film than 120. They likely do 120 in less frequent batches, which will give them better economies of scale in manufacturing (reducing the cost per roll for them and for us) but causing some lag in sale as the batches are sold.

I suspect the emulsion on 120 film is formulated to give best results with earlier use. Manufacturers assume that it will be used quickly by professional or high use amateurs. On the other hand 35mm is formulated for a long shelf life as a priority.

david b said:

The 120 might be older stock.

Just put the stuff in the fridge and don't worry about it.

Click to expand...

Agreed. The fridge takes all the worries out of issues like this.

I agree that the film is likely older stock. I imagine 120 film would not have the same volume of sales as 135. However, I've noted that some 120 films have differing development times than their 135 counterpart. Is it just due to developing to differing contrast or is there a slight formulation variance at play? Hmmm....

The paper backing on roll film, and the lack of a plastic storage cannister, might have a statistical effect on it's longevity.

Just a thought.

Matt

That production scale argument is convincing.

However, as Matt hinted at, type 120 and type 135 are different systems. Films are quite delicate items and parts of the system which will not draw the attention of a consumer could be effective to longevity.

Dave Miller said:

I suspect the emulsion on 120 film is formulated to give best results with earlier use. Manufacturers assume that it will be used quickly by professional or high use amateurs. On the other hand 35mm is formulated for a long shelf life as a priority.

Click to expand...

I think it's highly unlikely (indeed, utterly implausible) that they manufacture a different emulsion for 120 than 35mm because 120 is 'more professional.'

Fewer people buy 120. It sits on shelves longer. End of story.

120 is on a thinner base, so that may be a factor.

Dave Miller said:

I suspect the emulsion on 120 film is formulated to give best results with earlier use. Manufacturers assume that it will be used quickly by professional or high use amateurs. On the other hand 35mm is formulated for a long shelf life as a priority.

Click to expand...

Of course, you can only get one Christmas on a roll of 120, but you can fit three Christmases on a roll of 35mm.

tim_walls said:

I think it's highly unlikely (indeed, utterly implausible) that they manufacture a different emulsion for 120 than 35mm because 120 is 'more professional.'

Fewer people buy 120. It sits on shelves longer. End of story.

Click to expand...

I have 4 types of ilford 120 film in my fridge (D100, D3200, Fp4 and Hp5) and they all have dates between Feb and July 2009. They are from 4 different suppilers. If the life of the 120 film is the same as the 35mm (about 4 years) ilford must have gone on a production fest about 2 years ago...