Film Frame Spacing

[kdemas]

OK, this is getting a bit nerdy but what the heck. I just developed 5 or so rolls of film and I never cease to be amazed by the differing frame spacing from camera to camera.

My current fav is my Contax G2, nice wide (not too wide) spacing. Makes it easy to cut. Tightest spacing is the Nikon FM3A...tight, tight tight. Why does it matter? I find when they get too tight I can clip the edges of a few frames when cutting them, something my scanner doesn't like a whole lot.

The M5 also has fairly wide spacing.

Noticed any differences with your cameras? Have a favorite?

 

[Keith]

The closest I've seen so far is my Leica ll with a 15mm Heliar on it ... there's only a millimeter between the frames! And the largest gap I've experienced is my Widelux which has around five millimeters.

 

[kdemas]

1mm would be a little too tight for my kiddie snub nosed scissors!

 

[Keith]

1mm would be a little too tight for my kiddie snub nosed scissors!

A lot of it's to do with the superwide Heliar ... it's a lot more generous with a 50mm lens!

 

[kdemas]

A lot of it's to do with the superwide Heliar ... it's a lot more generous with a 50mm lens!

Interesting. I never really considered that the focal length could effect the frame size. I suppose if the gate has a little extra room, why not?

 

[Godfrey]

It has to do with the incident angle of light going to the edges of the frame. With a long lens, light rays reaching the edges of the frame are going through the format gate nearly perpendicular to the film. With a wide lens, the nodal point is close to the film plane and light strikes the film at an angle off perpendicular, growing the on-film image area by sneaking outside the format gate.

Just processed my first roll of film with the CL I acquired, almost all of it shot with the 40mm lens (I did fit the 90mm for a couple of frames). I'm delighted to see that the frame spacing is perfectly regular and even, a sign that the film transport is in very good shape. There's about 2.5mm between frames with the 40mm lens. I'll have to look at the 90mm frames and see if it's greater. 🙂

 

[Dwig]

The ISO standard is for a 38mm (exactly 8 sprocket hole) spacing, 36mm for a double-frame image and a 2mm gap between images. You'll probably find few cameras that don't follow the 38mm spacing. What will vary is the image width.

As Godfrey correctly stated, different lenses can throw different image widths since the film gate is not in contact with the film itself. The film rides on "rails" that range from 0.5-1mm high leaving a gap that the image can sneak under if the lens' exit pupil is close to the film. Even different lenses with the same focal length can image differently.

 

[zauhar]

My M3 produces variable spacing, sometimes too tight, my IIIf is uniform and fairly wide.

Solution - metal ruler and exacto knife.

Randy

 

[helen.HH]

hmmmm....
My M4 very Close
My M2 just a Touch Wider

 

[sepiareverb]

Totally differs with lens length- think about the angles involved. My G2 is 1mm with the 16mm, and way wide with the 45.

 

[John E Earley]

I find that medium format has more variation than 135.

 

[BTMarcais]

M3 with 21SA the frames have barely any space at all between them. The thickness of a hair or so. I ALWAYS know when I've shot something with that lens!

-Brian

 

[EdwardKaraa]

I might be mistaken, but I have noticed that film thickness plays a role, especially towards the end of the roll. The tightest spacings happen to slide film (thickest) while the widest spacing happens to B&W (thinnest).

 

[kdemas]

Very interesting! Although I understand the idea behind the focal length effect on the angle of light I always though the film gate would prohibit any extraneous image.

You learn something new every day 😉