Finding Old Negatives. What's a 4x5 ratio on 35mm stock?

I'm scanning some old negatives from the late 70's-early 80's. I found some on film that's the same width as my more modern 35mm negatives, but the frames are narrower than shots from my 35mm camera.

Measuring them in Lightroom, they're close to 4x5 ratio where "regular" 35mm film is 2x3 ratio.

I must have borrowed that camera from someone back then (before my first AE-1). What camera was I using? Anyone out there able to give me a clue?

I'm only guessing but they could be out of a 1/2 frame Olympus Pen..

A list of Half Frame Cameras

Thanks. That shook it loose. I seem to remember that my father's friend had an Olympus that he most likely let me borrow for that trip.

Olympus Pen (rangefinder), Pen F (SLR), Pen FT (SLR with TTL metering)

A 4×5 aspect on 135 stock would be an image of 30×24 (assuming full-width framing):

135 film had the following "standard" formats:

21×14mm
24×18mm
24×23mm
24×24mm
32×24mm
34×24mm
36×24mm
56×24mm
65×24mm

All of these sizes had cameras produced for them. The most popular, of course, was the 36×24mm "full-frame" format. The second most popular was the 24×18mm "half-frame" format.

These are just the "standard" formats. There undoubtedly were a few one-shot wonders as well.

20droger wrote in post #8630961
A 4×5 aspect on 135 stock would be an image of 30×24 (assuming full-width framing)... The second most popular was the 24×18mm "half-frame" format.

and 4x5 aspect in half frame would be 19.2 x 24mm

yogestee wrote in post #8625377
I'm only guessing but they could be out of a 1/2 frame Olympus Pen..

Like this one?

JWright wrote in post #8637851
Like this one?

Yes John..This is one of many Pen models..

Here are more http://www.olympus-global.com …rc/history/came​ra/pen.cfm