Crop lens on FF ISO performance

slip · 03-15-2016, 11:41 AM

Would the high ISO performance be better with a crop sensor lens on the K1 compared to the K5iis?

Thanks

Randy

Last edited by slip; 03-15-2016 at 03:13 PM. Reason: Mistake

bertwert · 03-15-2016, 12:07 PM

Yep.
Same pixel density (roughly) and newer tech.

mcgregni · 03-15-2016, 12:08 PM

I don't see how the crop would make any difference .... if the K1 has better performance than the K5II then it shouldn't make any difference what part of the sensor area you are looking at .... it should be better all over. I think we are expecting around a 2 stop improvement ..... ?

pathdoc · 03-15-2016, 12:12 PM

From what I've read here and elsewhere, it appears the noise has been cleaned up the equivalent of a stop or two over preceding efforts, so the answer is yes. This is one of the improvements I'd been hoping for that was actually fulfilled. No use having amazingly high ISO if you haven't done some work on what you've already got.

K-5 series still seems to be the king of low ISO, going down as far as 80; I have little doubt, however, that the K-1 at 100 is probably going to be considerably better.

Gimbal · 03-15-2016, 12:21 PM

Until actual measurements are in we can only guess the performance, but most likely the improvement will be very small if looked upon at a pixel level.
So in crop mode the performance will probably be slightly better, but not by much. Definitively not worth the money.

So don't buy a FF if you ONLY intend to use half the sensor.

Adam · 03-15-2016, 01:05 PM

Maybe a little, but certainly not by much since the cropped image area has roughly the same pixel density as the K-5. You do have access to pixel shift resolution and no AA filter, though, so this could potentially lead to sharper images.

Venom3300 · 03-15-2016, 01:27 PM

Its it expected to have a ~2 stop advantage. You are are cropping away one stop. So perhaps a 1 stop improvement? Don't expect a huge difference, especially at low ISO

2351HD · 03-15-2016, 01:40 PM - **1 Like**

Originally posted by Venom3300

Its it expected to have a ~2 stop advantage. You are are cropping away one stop. So perhaps a 1 stop improvement? Don't expect a huge difference, especially at low ISO

Could you possibly explain how you would be "cropping away" one stop.

A sensor is a sensor, regardless of what portion of it you use. Just because you crop the picture in photoshop or in camera, does not change the sensor properties.

So yes, the K1 would be the better sensor even if cropped to 16mp, especially considering how much effort Ricoh will have put into extracting all they can from this new sensor, with the old 16mp sensors being just that, old.

enoeske · 03-15-2016, 01:55 PM

Originally posted by 2351HD

Could you possibly explain how you would be "cropping away" one stop.

A sensor is a sensor, regardless of what portion of it you use. Just because you crop the picture in photoshop or in camera, does not change the sensor properties.

So yes, the K1 would be the better sensor even if cropped to 16mp, especially considering how much effort Ricoh will have put into extracting all they can from this new sensor, with the old 16mp sensors being just that, old.

Cropping it enlarges the noise/image ratio.

slip · 03-15-2016, 02:04 PM

Originally posted by enoeske

Cropping it enlarges the noise/image ratio.

that's what I was thinking

Randy

RonHendriks1966 · 03-15-2016, 02:12 PM

Expect it to perform equal to your K-5ii or just maybe a notch (1/3th stop) better.

christiandre · 03-15-2016, 02:19 PM

"Cropping it enlarge the noise/ image ratio"
....Even with a software crop ?

enoeske · 03-15-2016, 02:24 PM

Originally posted by christiandre

"Cropping it enlarge the noise/ image ratio"
....Even with a software crop ?

Try cropping a photo on your computer right now. Crop it enough and the noise gets really bad.

HavelockV · 03-15-2016, 02:29 PM

Originally posted by slip

Would the high ISO performance be better with a crop sensor lens be better then K5iis?

No more than a tiny bit (just the bit that technology has advanced). But nothing* from the sensor size (obviously).

With regards to noise we always only talk about "perceived noise" and that goes up with cropping and subsequent magnification to output size.

*=But: If the image circle is a little, say x1.2 larger than APSC then you can use it and need to magnify less, which will result in x1.2 less perceived noise.

By the way: Since your eyes don't resolve even 16 MPx from "normal viewing distance" you need to get closer to the output image to gain any benefit from the 16 MPx - thus effectively magnifying it then. Boom. Down goes your dynamic range and up shoots your perceived noise. Physics tell you there is a simple either/or decision to be made: enjoy either lowest perceived noise OR enjoying high resolution/details/sharpness. It is impossible to enjoy both at the same time.

christiandre · 03-15-2016, 02:33 PM

crop image in wildlife or birding practice, on a k1, will give the same result than a full k5IIs image ?
No différence, strictly ?

03-15-2016, 11:41 AM	#1
slip Veteran Member Join Date: Oct 2006 Location: 2 hours north of toronto ontario canada Photos: Gallery \| Albums Posts: 3,535	Crop lens on FF ISO performance Would the high ISO performance be better with a crop sensor lens on the K1 compared to the K5iis? Thanks Randy Last edited by slip; 03-15-2016 at 03:13 PM. Reason: Mistake

03-15-2016, 01:05 PM	#6
Adam Administrator Site Webmaster Join Date: Sep 2006 Location: Arizona Photos: Gallery \| Albums Posts: 51,593	Maybe a little, but certainly not by much since the cropped image area has roughly the same pixel density as the K-5. You do have access to pixel shift resolution and no AA filter, though, so this could potentially lead to sharper images. 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:

03-15-2016, 02:12 PM	#11
RonHendriks1966 Banned Join Date: Jan 2009 Photos: Gallery Posts: 9,675	Expect it to perform equal to your K-5ii or just maybe a notch (1/3th stop) better. Last edited by RonHendriks1966; 03-15-2016 at 03:16 PM.

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03-15-2016, 12:07 PM	#2
bertwert Veteran Member Join Date: Jun 2015 Location: Golden, BC Posts: 15,173	Yep. Same pixel density (roughly) and newer tech.

03-15-2016, 12:08 PM	#3
mcgregni Veteran Member Join Date: Sep 2012 Location: Surrey, England Posts: 2,603	I don't see how the crop would make any difference .... if the K1 has better performance than the K5II then it shouldn't make any difference what part of the sensor area you are looking at .... it should be better all over. I think we are expecting around a 2 stop improvement ..... ?

03-15-2016, 12:12 PM	#4
pathdoc Pentaxian Join Date: Mar 2015 Photos: Gallery \| Albums Posts: 6,381	From what I've read here and elsewhere, it appears the noise has been cleaned up the equivalent of a stop or two over preceding efforts, so the answer is yes. This is one of the improvements I'd been hoping for that was actually fulfilled. No use having amazingly high ISO if you haven't done some work on what you've already got. K-5 series still seems to be the king of low ISO, going down as far as 80; I have little doubt, however, that the K-1 at 100 is probably going to be considerably better.

03-15-2016, 12:21 PM	#5
Gimbal Pentaxian Join Date: Apr 2007 Location: Sweden Posts: 2,106	Until actual measurements are in we can only guess the performance, but most likely the improvement will be very small if looked upon at a pixel level. So in crop mode the performance will probably be slightly better, but not by much. Definitively not worth the money. So don't buy a FF if you ONLY intend to use half the sensor.

03-15-2016, 01:27 PM	#7
Venom3300 Veteran Member Join Date: Jul 2014 Posts: 714	Its it expected to have a ~2 stop advantage. You are are cropping away one stop. So perhaps a 1 stop improvement? Don't expect a huge difference, especially at low ISO

03-15-2016, 01:40 PM - 1 Like	#8
2351HD Veteran Member Join Date: Apr 2013 Location: Brisbane, Australia Photos: Albums Posts: 750	Originally posted by Venom3300 Its it expected to have a ~2 stop advantage. You are are cropping away one stop. So perhaps a 1 stop improvement? Don't expect a huge difference, especially at low ISO Could you possibly explain how you would be "cropping away" one stop. A sensor is a sensor, regardless of what portion of it you use. Just because you crop the picture in photoshop or in camera, does not change the sensor properties. So yes, the K1 would be the better sensor even if cropped to 16mp, especially considering how much effort Ricoh will have put into extracting all they can from this new sensor, with the old 16mp sensors being just that, old.

03-15-2016, 01:55 PM	#9
enoeske Veteran Member Join Date: Jul 2009 Location: Surprise, Az Photos: Gallery Posts: 2,136	Originally posted by 2351HD Could you possibly explain how you would be "cropping away" one stop. A sensor is a sensor, regardless of what portion of it you use. Just because you crop the picture in photoshop or in camera, does not change the sensor properties. So yes, the K1 would be the better sensor even if cropped to 16mp, especially considering how much effort Ricoh will have put into extracting all they can from this new sensor, with the old 16mp sensors being just that, old. Cropping it enlarges the noise/image ratio.

03-15-2016, 02:04 PM	#10
slip Veteran Member Join Date: Oct 2006 Location: 2 hours north of toronto ontario canada Photos: Gallery \| Albums Posts: 3,535 Original Poster	Originally posted by enoeske Cropping it enlarges the noise/image ratio. that's what I was thinking Randy

03-15-2016, 02:19 PM	#12
christiandre Inactive Account Join Date: Jul 2015 Posts: 157	"Cropping it enlarge the noise/ image ratio" ....Even with a software crop ?

03-15-2016, 02:24 PM	#13
enoeske Veteran Member Join Date: Jul 2009 Location: Surprise, Az Photos: Gallery Posts: 2,136	Originally posted by christiandre "Cropping it enlarge the noise/ image ratio" ....Even with a software crop ? Try cropping a photo on your computer right now. Crop it enough and the noise gets really bad.

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03-15-2016, 02:29 PM	#14
HavelockV Guest	Originally posted by slip Would the high ISO performance be better with a crop sensor lens be better then K5iis? No more than a tiny bit (just the bit that technology has advanced). But nothing* from the sensor size (obviously). With regards to noise we always only talk about "perceived noise" and that goes up with cropping and subsequent magnification to output size. *=But: If the image circle is a little, say x1.2 larger than APSC then you can use it and need to magnify less, which will result in x1.2 less perceived noise. By the way: Since your eyes don't resolve even 16 MPx from "normal viewing distance" you need to get closer to the output image to gain any benefit from the 16 MPx - thus effectively magnifying it then. Boom. Down goes your dynamic range and up shoots your perceived noise. Physics tell you there is a simple either/or decision to be made: enjoy either lowest perceived noise OR enjoying high resolution/details/sharpness. It is impossible to enjoy both at the same time.

03-15-2016, 02:33 PM	#15
christiandre Inactive Account Join Date: Jul 2015 Posts: 157	crop image in wildlife or birding practice, on a k1, will give the same result than a full k5IIs image ? No différence, strictly ?