How big is 5x7 film? 8x10 film?

[tim48v]

I mean exactly how big is a sheet of 5x7 or 8x10 film? We're thinking about doing larger versions of our SP-445 and need real data regarding film sizes. (We found that 4x5 varied from 98.4 to 99.7mm.)

If you'd like to contribute to our database, measure whatever film you've got laying around and send us the dimensions (include film brand/type). If you have a caliber, please include thickness. You can send it to info@stearmanpress.com.

Thanks,

Tim

 

[Ian Grant]

There's an ISO standard that covers these formats. it's gives the definitive format sizes. Glass plates are the full 7x5 and 10x8. film was used in adapters in plate holders so is slightly under sized as a consequence.

The specification of film holders has been published on the LFPF, this is the dimension you need rather than the slight variations in cutting.

Ian

 

[Rick A]

Simply subtract 1/10th inch from each dimension. 5x7=4.9x6.9.

 

[removed account4]

rick, i think it is 1/16 of an inch slenderer, for all sheet film formats ... 1/10th might still be a smidgen too wide and buckle.

 

[tim48v]

I already know that manufacturers aren't following any "standard" in the 4x5 world. I doubt they'll start following one the larger formats. The other issue, it is my understanding that the ISO standard was adopted in '98; there are still people shooting film older than that.

If we're going to drop thousands of dollars on a mold; we need empirical data regarding exact sizes (to the tenth of a mm) of as many different samples as we can find.

 

[Rick A]

rick, i think it is 1/16 of an inch slenderer, for all sheet film formats ... 1/10th might still be a smidgen too wide and buckle.

John, you are correct, I wasn't thinking clearly this morning.

 

[Ian Grant]

The current standards for sheet film sizes, and also the holder dimensions (internal & external) were agreed just after WWII and haven't changed since, only the ANSI, ASA, BS, DIN designations hav changed to become the overall ISO standard. So isntead of separate US. UK, German etc standars which were identical they are all now part of the International Standards Organisation (ISO).

Ian

 

[Old-N-Feeble]

I already know that manufacturers aren't following any "standard" in the 4x5 world. I doubt they'll start following one the larger formats. The other issue, it is my understanding that the ISO standard was adopted in '98; there are still people shooting film older than that.

If we're going to drop thousands of dollars on a mold; we need empirical data regarding exact sizes (to the tenth of a mm) of as many different samples as we can find.

Few people are going to measure that accurately and my guess is you'll get more inaccurate numbers than accurate ones. I'd suggest you buy as many examples of film you can find and measure them under controlled conditions.

 

[Ian Grant]

Just to add the ISO standards for both 7x5 and 10x8 films are based on Eastman Kodak sizes going back over 100 yerqas with no changes. The only two film sizes I know that aren't part of the ISO standards are 1/2 plate and Whole plate, two British sizes covered by BS (British Standards) but no longer made by the time of the ISO standards which has caused issue when American s asked for whole plate cameras from Japan amd no-one knew the standard

Over 10x8 it's similar though as the US used totally different sizes to the UK and Europe was different as well.

Ian

 

[Luis-F-S]

Why not buy a small box of each and measure it yourself so you're not taking someone else's word for it?

 

[DREW WILEY]

Always measure polyester-based film, not acetate, since acetate is not dimensionally stable.

 

[John Koehrer]

Why not buy a small box of each and measure it yourself so you're not taking someone else's word for it?

^^^It's only money(his).......

 

[greg zinselmeier]

i'm confused. . . . . . again! am I going to get paid for this? what equipment to I need to buy to measure "this film"? Will I be re-imbursed for the purchase of this measuring device? How does one accurately measure? anyway. . . ?

 

[Doremus Scudder]

I would think that the ISO standards would suffice. If not, measure film from the major manufacturers. Ilford and Kodak have standards (probably the ISO ones) and supply the vast majority of film in those sizes. I can't imagine anyone making a filmholder that wouldn't fit Ilford and Kodak film... There must be tolerances too.

And, while you're measuring, get your hands on filmholders from Toyo and Riteway/Fidelity and measure those too.

And, you could give Hugo at Chamonix a call or a message asking for information. Heck contact Toyo and Lotus and any other manufacturers that make film and holders and ask them too.

Or, use the ISO standards...

 

[TheToadMen]

For stating the obvious:
* 13x18 cm is not 5x7 inch,
* 18x24 cm is 8x10 inch.
Still, these are often confused, mixed, misleading, generalized, ...

 

[Marttiko]

For stating the obvious:
* 13x18 cm is not 5x7 inch,
* 18x24 cm is 8x10 inch.
Still, these are often confused, mixed, misleading, generalized, ...

But 5"x7" and 13x18cm are quite close to each other. 5x7 inch Foma paper fits nicely in my FKD 13x18 cm plate holders.
That doesn't mean they are the same and always interchangeable.

 

[DREW WILEY]

The outside dimension of the 13x18 and 5x7 filmholders are the same, so that you can use the same camera for both, but the inside dimension - the
slots where the film itself slides in - are different, which means you must have the correct holder for the respective film size.

 

[TheToadMen]

But 5"x7" and 13x18cm are quite close to each other. 5x7 inch Foma paper fits nicely in my FKD 13x18 cm plate holders.
That doesn't mean they are the same and always interchangeable.

They are close, but not the same. So with some combinations of film and holder the film might fall out of the cassette when you open the dark slide.

 

[Ian Grant]

The outside dimension of the 13x18 and 5x7 filmholders are the same, so that you can use the same camera for both, but the inside dimension - the
slots where the film itself slides in - are different, which means you must have the correct holder for the respective film size.

The outside dimension of modern Half plate holders are the same as well so my post WWII Kodak lLtd half plate film holders fit my warly 1900's Seneca 7x5 cameras perfectly.

Eastman Kodak made a 7x5 camera, while Kodak Ltd sold a British made camera almost identical which was half plate, and in Continental Europe was 13x18.

Ian

 

[DREW WILEY]

7x5 film won't fit in a 5x7 holder either because you're trying to slide it in sideways!

 

[TheToadMen]

7x5 film won't fit in a 5x7 holder either because you're trying to slide it in sideways!

There is only one serious answer for this:





Duct tape!

 

[tim48v]

Any engineer that trusts his suppliers to follow a standard is, to be polite, naive.

 

[Ian Grant]

It's the film holder size that's critical particularly for your application as your sizes need to mirror these. The actual variations in film size are important only because if to wide or long the film won't fit the holders and too narrow will fall out in use.

This is supposed to be the ANSI standard for film holders, it's in inches, the ISO standard will be metric. It doesn't give you the size (width) of the two lips either side that hold the film in place and that varies slightly between different makes of holder.

It's very unusual film doesn't fit holders, the only issue I can remember was J&C having Chinese sheet film cut for them a few years ago and it wouldn't fit most film holders, John had ordered 5x4, 7x5 etc the Chinese had cut the film to the nominal size rather than the correct slightly smaller szes needed to fit holders. Ilford made the same mistake when first testing their Harman Direct Positive paper, they cut to the paper sizes forgetting the films sizes differed.

Ian

 

[Jim Jones]

Ian, the errors in this citation have been discussed elsewhere. I don't have time to list them at the moment. Someone with a serious need for accurate information can get the present standard specifications for a price, perhaps $25.

 

[DREW WILEY]

Some of J&C's EU specialty films were also incorrectly cut. That's ancient history by now, but just one more reason to not take things for granted.
Even more disappointing is the fact that numerous EU sheet film boxes themselves leaked light at the corners. So you always had to put unused sheets back in the black plastic pouch and carefully roll and tape the front of that, before going back in the box or else transfer them into triple-lid film boxes from somebody else, like Kodak.