Is 9x12 = 4x5 ?

[gliderbee]

Because of my suprise about 5x7 filmholders not all being able to hold 13x18 (cm) film, I thought I'd better ask first:

On German eBay, I often see 9x12 (cm) filmholders (Fidelity Elite). Are these the same is the "usual" 4x5 filmholders ?

Thanks,
Stefan.

[Ole Tjugen]

NO, the difference is even greater than between 5x7"/13x18cm film holders. External measures are the same, film size is very different.

[gliderbee]

Thanks, that's what I expected ...

Stefan.

[Emmanuel BIGLER]

hello from old Europe.
We can add that post-WW-II "international" holders have the same external dimensions as mentioned by Ole.
However before WW-II there has been many different kind of 9x12 glass plate holders and cut-film golders (Ole knows them much better than me ), not at all compatible with modern "international" holders. However there were some septums available to load 9x12 cm cut-film inside a 9x12 cm glass plate holder.

Modern 9x12 Linhof "thick" holders have a pressure plate, they can allow either a cut film of a glass plate if this plate is not too thick ; 1.9mm thick is something that the 9x12 Linhof holder can accommodate.

4x5" film size is about .. 4x5" in external film dimension (102x127 mm) ) but actual image size is about 6-7mm (1/4") smaller; yielding a useable image size of about 94x120 mm
In 9x12, film size is, no surprise, about 90x120 mm in external dimansions, useable image size is about 84x114 mm; this final size actually depends on the kind of holder.
The ANSI standard defines all important sizes for International holders

There used to be web page listing important data for modern "international" film holder dimensions but I can't find it any more.


And to end with the series:
6.5x9 cm "European" cut film size is in fact 6.35x9 cm = 2-1/2" by 3-1/2" whereas "American" 2x3 cut film is in fact 2-1/4" by 3-1/4" and again international holders look the same and have the same external size, the baby-graflok size in 2X3" - 6x9, but the inside differs.

There also exist (existed ?) 18x24 cm 'international' cut-film holders similar to 8x10" modern holders and, again, film sizes are very different, 18x24 cm being much smaller than 8x10" film.

[Ole Tjugen]

Actual film size is in most cases about 3mm smaller than the nominal size. The reason for this is that glass plates were "full size", so when film was introduced they needed septums to hold the film flat. Since the septum was the same size as the glass plate, the film had to be a few mm smaller to fit inside.

You can still get 18x24cm film (and holders) - I use quite a bit of it. I like the aspect ratio of the narrower European formats better than the more square-ish inch sizes.

[Emmanuel BIGLER]

Actual film size is in most cases about 3mm smaller than the nominal size. The reason for this is that glass plates were "full size", so when film was introduced they needed septums to hold the film flat.

Thanks again, Ole, this is perfectly clear.
And to add some real values to the discussion, I just measured a freshly processed & dried 9x12 film and found an actual size equal to 90x120 mm minus about 1.5 mm in each direction, i.e. actual size = 88.5 x 118.5 mm

[IanG]

Add another fly in the ointment as the pre-WWII 9x12 cameras were sometimes sold with Quarter plate holders and/or film packs.

Quarter plate is a touch smaller than 9x12 so this was quite simple, it's just slightly square/shorter and was a British & US format, so outside the Continent you often find German cameras sold with 9x12 or Quarter plate backs.

Ian