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10-08-2016, 08:10 PM   #31

Join Date: Sep 2011
Location: Nelson B.C.
Posts: 3,241
QuoteOriginally posted by normhead Quote
I clearly didn't read your post carefully enough, my apologies.

But right off th stop, the high ISO difference isn't as much as one might think. The k-3 is shot at ISO 400, but to get the same DoF on the K-1 I would have had to shoot at 8 and 800 ISO. So the actual improvement is about 1 stop. In these examples the K-3 image is actually the better image because shot at 5.6 compared to 4.5 (wide open) on the K-1 image the birds beak is in focus, but out of focus on the K-1 image. So there are times when the lower noise values of the K-1 aren't enough to compensate for the advantages the K-3 presents. Every set up presents it's challenges.

ISO 100 , and 5.6, K-3 with my DA*200, K-1 with my Tamron SP AF 300, the K-3 set up will have more depth of field, and that may be enough to push the K-3 image ahead of the K-1 image, in some cases.
I've noticed the biggest difference when there is little light. The K3 quality degraded substantially above 800. I usually tried to keep below 1600. Which means that shutter speeds are low. When there is lots of light the K1 is only marginally better all things considered.

It makes it possible to shoot wildlife at dawn and dusk.

10-08-2016, 08:26 PM   #32

Join Date: May 2009
Location: Ponoka Alberta Canada
Photos: Gallery
Posts: 509
QuoteOriginally posted by Fogel70 Quote
DxOmark data also show that K1 has better performance on APS-C crop than K3 II.
Their data show that FI K1 has around 0.5 stop advantage in APS-C crop on noise performance vs K3 II.
All test images I have seen show the same thing.

It would be interesting to see your images to compare. There are many things that can differ and affect the result, from individual camera that don't perform the same, software processing that are not exactly the same, performance on lenses...

See FI below result from dpr where K1 (FF) has ~1.5 stop NR advantage over K3 II (APS-C). On APS-C crop K1 would have ~0.5 stop advantage over K3 II.

For a sensor to have a Full stop increase in light gather ablitlty ( ignoring the technology gains) the sensor has to be double. Part of what you are seeing here in your demonstration is that the K1 has 1/3 of a stop more light being projected onto it and at these exposures you start to notice that noise more. The reason for this is that the K3 has a crop factor of 1.5+- and equates to a size difference of 2.25 and when you adjusted the iso you done so at a full stop (doubling), so when you say you see a .5 stop gain over half of that is do to being exposed to more light by 1/3 of a stop.

Now under most shooting conditions most will not see any difference.

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