ISO & Noise

There was a recent topic in one of the Canon Photo Forums as follows:-
"Canon cameras have least noise at 100/200/400/800/1600 ISO and not the settings in between".

So this guy was saying that he had a lot of noise at ISO 640 from his Canon 6D. He had posted the photo + a 100% crop. He also mentioned the photo was not tack sharp.
Now it is well known that the Canon 6D is renowned for it`s low noise and one wouldn`t expect to see this at ISO 640.

So the question and clarification I am seeking is, does Pentax DSLRs, the K-5 & K-3 series, have the same failings as this statement "Canon cameras have least noise at 100/200/400/800/1600 ISO and not the settings in between".

Thanks

I have never owned a Canon so can't compare, but my view is that noise is very well controlled on my K3 and K5II.
That said in the dark, for example at a gig, I never push the ISO above 1600. I have ventured as high as 3200 but by then noise is pretty evident.
I did own a Nikon D7100 but on that noise was an issue from ISO 640 up.
Not sure this answers your question, but I would imagine all brands are pretty much of a muchness once you start to push the ISO.

The 18mp sensor in my little Canon EOS M is quite noisy at even moderate apertures and nowhere near as clean as that in my K5 which is astonishingly noise free. I'm happy to use the Canon at up to 800 ASA and with careful processing the images are fine, exceptionally nice for such a tiny camera, in fact.

I read somewhere that intermediate settings were a bit noisier due to the processor pushing or pulling the files but I wouldn't know. Canon make their own sensors; I think Pentax and Nikon use Sony sensors.

'Failings'!?
Noise isn't the result of anything failing. It's a consequence of science and physics.

It's nice to hear that Canon users are as daft as us!

The answer lies within

--

Dear Steve, we value your thinking & the post. But do note all photographic sensors are not the same. Some have great DR and Noise Control built in. And some cameras have a great "photo engine" to keep noise down through software.
My K20D had little or no noise at 800 ISO. This was upped to 1200 ISO on the K-5 and 1600 ISO on the K-5 IIS. And sensors getting better with technology.
Now my query was related to this report on the Canon Forum: "Noise was almost absent at 100/200/400/800/1600 ISO. But when an intermediate setting was used on the Canon 6D like ISO 640, there was discernible noise".
The query: Do Pentax DSLRs demonstrate this same behavior??
For all I know I may be asking an un-scientific question, perhaps stupid to you Steve.
Regards.

Dear nanhi,

Like most things in photography, it depends and It's subjective. If you want hard and fast comparisons with detailed results you really do need to get 'scientific'.
My point was that it's not a failing, it's a consequence of design. (You confirmed that you understand this by writing "But do note all photographic sensors are not the same. ")
My recommendation would be to study sample RAW files.
For example, some can be found here:
► http://www.rawsamples.ch/index.php/en/pentax

I think the original question relates to whether or not settings that are between the main 100/200/400 etc steps exhibit more noise than the main settings. So, ISO 320 could be noisier than ISO 400., for example.

In a simplistic sense it's hard to see why this would be so if ISO is in effect just a turning up of amplification. However, there may well be much more than that going on, so the only way to be sure would be to ask the engineers, who are not accessible to us, or run an experiment to find out.

To prove it would involve the complicated business of taking TWO SHOTS one at say 640 ISO and one and 800 ISO and comparing them ...... Far too difficult for a Pentaxian they prefer to waffle on about it This would be good for about 40 pages of waffle on the US forum.

I did post the results of a test I did sometime back on a K-5, but can't find the files.

It's also mentioned in camera reviews. Anyone who knows how to use a camera knows that you should stick to 100/200/400/800/1600 ISO because generally the noise from 500 and 640 ISO is the same as 800 ISO...... I thought even Canon users would know that

--

Does it really matter, Use the lowest Iso rating if possible, If not use a higher one.
I use up to 25600 . So It looks a bit grainy. But i have the photo I was after. Sometimes a bit grain looks quite good.
However If you are really worried about a to high Iso rating, or worried the in between are noisier, just use a tripod and set it to the lowest rating you feel comfortable with .

To me , it matters more what is on the picture than a bit of noise.
The picture below was taken with an iso rating of 12800.
I don't think it looses anything because of a bit of noise.


Regards, Horst

Thanks Algernon Sir, yours was the best & the clearest answer, and a very obvious one. No ifs & buts, no vague words like "it depends or subjective".
This could be one reason why someone on the Pentax Forums said to use Full ISO steps in the camera settings instead of Half or One-Third steps.
Regards.

It looks to me as though noise progresses steadily through the ISO settings...



(100% crops)

...but the difference between one and the next would probably not be noticeable in images seen at at typical viewing sizes and distances.

Cheers.
Philip

Thanks Philip, that's what I would expect.

I'd have though that too, if there's something else at play then it renders the Pentax TAv mode a bit hit and miss with regards to getting an image with acceptable noise levels.

I can't remember the tech sites I saw this on, but this site does mention it as well so it must be somewhere. See No:2 in 'Tips to Combat Noise Generation' keep your ISO setting to the industry standard numbers – 100, 200, 400, 800, 1600, 3200, etc.

--