The pictures first - and then the narrative for anyone who cares...





These pictures were taken (of me) by my wife last night using K-7 with 50-135mm. Both were taken using pttl - off camera flash. Both were at ISO 1250; xsync (1/180); F2.8.

Although it was a mistake of her not to use much lower shutter speed and ISO settings these pictures demonstrate both an exceptionally good thing and a bad thing about K-7.

The Good. These are very low light action shots taken at very wide aperture (f2.8) and the focus could not have been more perfect. I was quite surprised to see just how well the camera performed here.

The Bad. This camera truly is awful at high ISO. Although the images are perfectly sharp they appear "soft" because there is so much noise in the image. Even after running the photo through noise ninja considerable noise remains and the image has lost much detail. By today's standards ISO 1250 is NOT that high and it would be really nice if Pentax could fix this for us. Here is a crop for anyone interested... http://christopherwood.smugmug.com/photos/646213389_jxkTP-XL.jpg

I figured rather than posting YET ANOTHER thread in the forum about K-7 noise I'd just share the pictures and let people have a look for themselves

[Ash]

Good samples and food for thought.
Were the photos needing any 'pushing' in PP that may have caused any noise amplification?
What were your NR and sharpness settings? Were you shooting in RAW?
This may indeed show the limitations of high ISO noise on this CMOS sensor, but other factors should be explored as I know I have a few ISO 1600 photos which have come out at least a little sharper than this one has.

[cwood]

photos were taken in DNG RAW. Post processing involved selective reduction of brightness on my face (the flash came out a little harsh) but there was no EV compensation

[JMR]

I like your shots and appreciate the information that you have provided. But I do not agree with the comments about how low noise, high ISO's, are a norm for cameras today. This is still a controversial claim and many claims are being made by various companies. Leica just released a very expensive camera and it's high ISO results are reported to be less than the top cameras from Nikon and Canon. So why release an expensive camera that can't reproduce the results of the other companies? Probably because the camera performs very well on the more used ISO range, just like Pentax. And I would venture to say almost all the top camera companies today are not much different from each other in the normal ranges. And the claims from any company of high performance at the high end ISO ranges continues to be controversial.

JMR

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Last edited by JMR; 09-11-2009 at 07:12 PM.

[maritimer]

And the claims from any company of high performance at the high end ISO ranges continues to be controversial.

IDK about this statement, JMR. Go here http://www.fredmiranda.com/forum/ and check out the Nature forum. Most are shot w/ the 5d and 5d III from Cannon and a lot of D700 and D300's ( have yet to see any Pentax exif data on this site ) and a very high amount are shot at well over 1600 ISO. I will tell you this for sure: same conditions and an equivalent lens, there is no way my K10D can do what these cameras can in terms of high ISO performance.

Even on a great exposure, the noise @ 400+ ISO on my K10D is simply unbearable and many times while shooting wildlife early in the A.M. I've cursed myself for staying w/ Pentax after switching to digital. I sell alot of landscape and wildlife prints and I wouldn't dare risk my budding reputation by selling images with noise in them. I've come to this conclusion : if I have to go over 200 ISO I don't even bother trying to get the shot... that's pretty sad I think. I've tested K20's and K-7's in the same conditions and gotten very similar results. Pretty much why I haven't upgraded

[krypticide]

To be honest, I really doubt that is high ISO noise. It looks to me like oversharpening of areas without detail. I would check your RAW conversion.

The K-7 high ISO is comparable to the K20D, and I get stellar images from the K20D at 1600 and even 3200 (when properly exposed).

[axl]

@maritimer:
let's not go down the way of comparing K10D with D300&700 or top line Canons. I think we've passed that. You want better high ISO? All you have to do is simply pay for it a lot more...

BR
Peter

[maritimer]

axl,

Oh no arguement here... I should have been more clear and made sure I wasn't sounding like I was comparing systems. I was just making a point that some cameras really do live up to their very high ISO performance.

The part about my K10 ( and the other 2 I've tested / tried out ) was simply a form of declaring anguish I guess ; not really wanting to fully admit I may have to switch systems. Pentax has always been great for me, but the last few months I'm discovering limiting weaknessess that, at one point, weren't really an issue.

my apologies