When it comes to noise, it seems like there is almost a mythical aura surrounding the 5D, especially within 5D owner’s communities. According to some forums, all other cameras fall completely short of the 5D’s noise performance.

Yes – it performs really well but I must say that there is no quantum leap compared with my old 1Ds (which is not known for good noise performance) or my 1D2 (R.I.P)

My own rule is that I always strive to “expose to the right”, i.e. pushing the histogram as far as possible to the right without destroying too much of the highlights. High DR scenes forces a compromise and my experience is that the worst thing that can be done from a noise perspective is to compensate a high-DR scene ONLY for the highlights, i.e. striving to recover the shadows in the post processing. As long as the majority of the pixels are in the middle and right part of the histogram, noise is not a catastrophic problem even on the 10D and 1Ds, even at higher ISOs.

Of course, a low-light scene with deep shadows at ISO 1250 shows a very pronounced level of noise on the 1Ds whereas the 5D handle it ways better.

However, pumped-up shadows expose noise and the deep shadows do not get pretty when the noise below the S/N threshold is amplified. That’s simple physics as I see it and unless real compromises in detail resolution can be accepted by the means of noise reduction software, there is not very much to do about it. Unless exposing to the right of course…

I’ve tried to find any means of banding or other fixed pattern noise, but as far as I can see, Canon’s lead in CMOS sensor technology is there and they deserve it. Expecting to recover details in deep shadows at ISO 3200 is nothing but meaningless and it somewhat irritates me how some people scream in forums when they find shadow noise at high ISOs. Let’s face it – ISO 3200 isn’t there to make deep shadows visible, it’s there to make the middle and right part of the histogram really, really enjoyable at this amazing level of amplification.

Whenever I get back to my ISO 400 Tri-X film shorts, I get shocked how much grain there is. We’re spoiled !

Amplifying noise from the 1Ds reveals according to my subjective taste a very evenly distributed sand-like or grain-like noise and the chroma noise is fairly low in most cases.

Although the 5D is superior at higher ISO settings, it is very obvious that there is some serious in-camera noise-processing taking place. Amplifying the 5D noise reveals more chroma noise and it does not look equally evenly distributed. But nevertheless, the 5D detail resolution at higher ISO settings in very, very good.

High ISO comparisons are made at ISO1250, which is the highest setting for the 1Ds. I've made some tests at ISO 800 and 400 as well, but my subjective impression is that the noise figure scales fairly linear between ISO 200 and ISO 1250.

Some additional samples are added to show what shadow noise can really be like in a real world setting...
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