Pentax K5 ISO test2, *Warning image intensive*


armadillo

Senior Member
Jan 30, 2006
1,376
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Pinnacle@Duxton
Under T5 fluorescent light:
Below image just resize only, no pp.
ISO 80
pk5b-iso80.jpg


ISO 100
pk5b-iso100.jpg


ISO 200
pk5b-iso200.jpg


ISO 400
pk5b-iso400.jpg
 

ISO 12800
pk5b-iso12800.jpg


ISO 25600
pk5b-iso25600.jpg


ISO 25600, with topaz denoise
pk5b-iso25600-topaz.jpg
 

ISO 51200 NR set to off
pk5b-iso51200-no-nr.jpg


ISO 51200, with camera set to NR-low
pk5b-iso51200-nr-low.jpg


ISO 51200, with camera set to NR-medium
pk5b-iso51200-nr-med.jpg


ISO 51200, with camera set to NR-high
pk5b-iso51200-nr-hi.jpg
 

With 100% crops, in the centre:
ISO 80
cpk5b-iso80.jpg


ISO 100
cpk5b-iso100.jpg


ISO 200
cpk5b-iso200.jpg


ISO 400
cpk5b-iso400.jpg
 

ISO 12800
cpk5b-iso12800.jpg


ISO 25600
cpk5b-iso25600.jpg


ISO 25600, with topaz denoise
cpk5b-iso25600-topaz.jpg
 

ISO 51200, NR set to off
cpk5b-iso51200-no-nr.jpg


ISO 51200, with camera set to NR-low
cpk5b-iso51200-nr-low.jpg


ISO 51200, with camera set to NR-medium
cpk5b-iso51200-nr-med.jpg


ISO 51200, with camera set to NR-high
cpk5b-iso51200-nr-hi.jpg
 

Thanks for the hard work!

With regards to JPEG
I have now turned off NR from 12800 onwards. I find that the grains are very even if no NR is done, and lots more details are retained. This allows me to NR in a better system like Topaz Denoise or do nothing and leave the nice grain and details at discretion.
The in camera NR while good, does not add much esp after comparing to non NR shots.

I am now trying to experiment with RAW to see if the NR mileage improves significantly.
 

Yeah, now I set all the camera NR to off.
If really need to clear noise then use external software :)
 

Yeah, now I set all the camera NR to off.
If really need to clear noise then use external software :)

there is OBVIOUS NR going on with the ISO3200 pic. and maybe even the ISO1600. I think it is true that Pentax does NR at raw file level so you can NEVER turn of NR completely. Which is bad.

Look at the fine detail at the blue regions in the top right corner.
 

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there is OBVIOUS NR going on with the ISO3200 pic. and maybe even the ISO1600. I think it is true that Pentax does NR at raw file level so you can NEVER turn of NR completely. Which is bad.

Look at the fine detail at the blue regions in the top right corner.

If TS did the shots on Auto ISO NR, then NR kicks in from ISO800 on low, and on 1600, 3200 they are on mid.
He did comment that now, after his own evaluations, he has found that turning off is the best option for him.

I don't understand how you come to the conclusion here on very obvious forced NR on 1600 onwards. Can you care to elaborate on the obvious NR'ed area? Frankly, I can't really see it atm. You may be mistaking the uneven dispersion of blue that is inherent on the cardboard itself. These appear everywhere on the card even from ISO80.

If you have an opinion on how a good ISO1600, 3200 photo with no NR and good detail retention looks like. Pls post them here for information and discussion.
 

there is OBVIOUS NR going on with the ISO3200 pic. and maybe even the ISO1600. I think it is true that Pentax does NR at raw file level so you can NEVER turn of NR completely. Which is bad.

Look at the fine detail at the blue regions in the top right corner.
Just to confirm camera NR definately set to OFF.
are you referring top right corner or top left corner? (bcos top right corner don't hv blue color)
I suppose you seeing the 100% crop picture.
 

Arm, bring it to the 50 storey SB leh..... try to shoot the CBD night view, freehand. :D

Actually if you ask me, need to shoot a picture with say 4 pax, group photo. For my wedding use I cannot stand the "watercolour" NR quality. The clients can stand noise, but not watercolour. It seems that 3200 already shows that watercolour quality. I think I saw some of fengwei shots, but from experience there is a diff bt 4-8 pax group photo and 1-person group photo (its hard to explain).
Basically, ditch these test shots. Go out and shoot. You can only gauge from there, there is a base ref to the real thing.

Anyway its not jpg compression, I can differentiate between that and the watercolour NR.
 

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I don't understand how you come to the conclusion here on very obvious forced NR on 1600 onwards. Can you care to elaborate on the obvious NR'ed area?

Check out all the lines, between the different colours, straight or cuved.

Its very difficult to explain. Like i told arm, just take a group picture, 4-8 pax is good. 20 pax is acid test and you may not be able to interprete the pix as its too much info (overload), but 4-8 is cool. 1 pax not enough features.
The impt thing is to have fun in the photography process as well, so its impt to shoot real stuff which makes it fun as well. :)
 

Just to confirm camera NR definately set to OFF.
are you referring top right corner or top left corner? (bcos top right corner don't hv blue color)
I suppose you seeing the 100% crop picture.

Sorry, top LEFT... can never tell left and right :)

You can check you ISO80 and ISO100 pics and you can see some sort of consistent pattern in the blue region which is probably there is real life.

This pattern however is gone at the ISO3200 pic even though the pic is still very noiseless. So to me there is NR even though you set it to off.

I think pentax do force NR on the raw files so we need to consider that when comparing pics between different cameras.

Not that I am saying K-5 high ISO is poor. Even considering that, I still think that it is the BEST high ISO APS-C camera out there.

But some saying that it is better than the D700 is a probably not true. But it looks pretty close to what I get from my D700.
 

BTW, the DXOmark results for K-5 just came out and they agreed that ISO3200 and above has forced NR as seen by the SNR curve.

The high ISO noise performance looks similar to nikon D90 actually. But the STUNNING results is how good the k-5 is at ISO 80 which I feel is FAR FAR more useful than ISO3200.

The dynamic range is a mind boggling 14ev. I think that is D3x range.... wow....