K-1 crop factor for 1 to 1 mode

**mlt** · 04-21-2017, 09:19 PM

Is there an crop factor multiple when using the 1 to 1 crop mode relative to full frame lens focal length? The exif info shows the full frame focal length when bringing raw in to Lightroom.

Thanks

**UncleVanya** · 04-21-2017, 09:45 PM

Do you mean the square crop?

Adam · 04-21-2017, 09:47 PM - **2 Likes**

Don't even go there, focal length is focal length

The metadata should tell you whether or not the image was taken in crop mode (and you can tell by the aspect/filesize).

**UncleVanya** · 04-21-2017, 10:06 PM

A square crop I think is about a 1.27x crop if you go by diagonal measure only. I am tired and I may be off on my math.
Since the aspect ratio is different it is harder to really compare directly. It is like taking a 6x9 format and comparing to a shot on 6x6 - the verticals are unchanged only the width really changed.

leekil · 04-21-2017, 10:30 PM

It's a 1.00x crop factor multiple, vertically.

Class A · 04-21-2017, 11:54 PM

Originally posted by UncleVanya

A square crop I think is about a 1.27x crop if you go by diagonal measure only. I am tired and I may be off on my math.

Your math isn't off.

Technically, the crop factor is the quotient of the image diagonals, so in this case it is 1.27475...

pathdoc · 04-22-2017, 03:23 AM

You can't really compare the crops as they are of different length-width ratio (aspect ratio), but the crop factor on a 6x6 camera is close to 6:1; your K-1 lenses will not cover the full 6x6 image circle

Not a Number · 04-22-2017, 10:08 AM

The relative horizontal field of view would be cropped. But why would it matter if you are composing you shots through the viewfinder and not with a tape measure.

surfar · 04-22-2017, 10:36 AM

Its one....square crop chops the ends off .

**Kerrowdown** · 04-22-2017, 02:01 PM

Originally posted by Adam

Don't even go there

Someone had to say it, but didn't think it would be the boss.

04-21-2017, 09:19 PM	#1
mlt Site Supporter Join Date: Dec 2007 Posts: 1,159	K-1 crop factor for 1 to 1 mode Is there an crop factor multiple when using the 1 to 1 crop mode relative to full frame lens focal length? The exif info shows the full frame focal length when bringing raw in to Lightroom. Thanks

04-21-2017, 09:47 PM - 2 Likes	#3
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,595	Don't even go there, focal length is focal length The metadata should tell you whether or not the image was taken in crop mode (and you can tell by the aspect/filesize). Adam PentaxForums.com Webmaster (Site Usage Guide \| Site Help \| My Photography) PentaxForums.com server and development costs are user-supported. You can help cover these costs by donating or purchasing one of our Pentax eBooks. Or, buy your photo gear from our affiliates, Adorama, B&H Photo, KEH, or Topaz Labs, and get FREE Marketplace access - click here to see how! Trusted Pentax retailers:

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04-21-2017, 09:45 PM	#2
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,401	Do you mean the square crop?

04-21-2017, 10:06 PM	#4
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,401	A square crop I think is about a 1.27x crop if you go by diagonal measure only. I am tired and I may be off on my math. Since the aspect ratio is different it is harder to really compare directly. It is like taking a 6x9 format and comparing to a shot on 6x6 - the verticals are unchanged only the width really changed.

04-21-2017, 10:30 PM	#5
leekil Pentaxian Join Date: May 2016 Photos: Albums Posts: 2,003	It's a 1.00x crop factor multiple, vertically.

04-21-2017, 11:54 PM	#6
Class A Pentaxian Join Date: Aug 2008 Location: Wellington, New Zealand Posts: 11,251	Originally posted by UncleVanya A square crop I think is about a 1.27x crop if you go by diagonal measure only. I am tired and I may be off on my math. Your math isn't off. Technically, the crop factor is the quotient of the image diagonals, so in this case it is 1.27475...

04-22-2017, 03:23 AM	#7
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	You can't really compare the crops as they are of different length-width ratio (aspect ratio), but the crop factor on a 6x6 camera is close to 6:1; your K-1 lenses will not cover the full 6x6 image circle

04-22-2017, 10:08 AM	#8
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	The relative horizontal field of view would be cropped. But why would it matter if you are composing you shots through the viewfinder and not with a tape measure.

04-22-2017, 10:36 AM	#9
surfar Pentaxian Join Date: Jan 2015 Location: mid nth coast,nsw Photos: Gallery Posts: 6,141	Its one....square crop chops the ends off .

04-22-2017, 02:01 PM	#10
Kerrowdown PEG Moderator Join Date: Aug 2008 Location: Highlands of Scotland... "Hold Infinity in the palm of your hand" - William Blake Photos: Gallery Posts: 57,818	Originally posted by Adam Don't even go there Someone had to say it, but didn't think it would be the boss.