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What aspect ratios do Pentax users like?

Started Oct 5, 2020 | Discussions thread
Mark Ransom
Mark Ransom Veteran Member • Posts: 8,209
Re: 7x5
1

MrB1 wrote:

MightyMike wrote:

GossCTP wrote:

MightyMike wrote:

Mark Ransom wrote:

The 5x7 aspect ratio of 1.4 is very similar to the ISO A size aspect ratio of 1.414. A very practical choice. Unfortunate that no cameras do it natively.

display ratios really have nothing in common with the stop ratios we use for ISO, aperture and shutter speed... So I'm basically saying the connection is completely irrelevant.

Unless I've missed something, he was saying the 7x5 was the same dimensions as A paper (e.g. A4).

No you didn't miss something... I did... my bad... I thought he was talking about the square root of 2

I made the point about 5:7 (1:1.4) being close to the aspect ratio of the A series papers in a previous post above.

And yes, the A series does use the square root of 2, its aspect ratio being 1:1.414, as Mark has written here.

Philip

Exactly, the A series uses the square root of 2.  And that was not an accident, they wanted to be able to cut one size exactly in half to get the next size down but retain the same aspect ratio.  Cut an A4 in half, get two A5s.  Very clever, really.

 Mark Ransom's gear list:Mark Ransom's gear list
Pentax K-7 Pentax K-01 Olympus E-M5 II Pentax smc DA 15mm F4 ED AL Limited Pentax smc DA 18-135mm F3.5-5.6ED AL [IF] DC WR +6 more
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