High ISO - A must-read for digital users

[Bearface]

Some of you might already have seen this, but this article over at DP Review discusses in some detail the subject of high ISOs in digital photography (more specifically relating to compact digicams) and also dispels some of the myths associated with it.

For those people who have little or no understanding of how the whole ISO thing works in the context of digital cameras, I think it makes for pretty interesting reading. Worth a look when you have five minutes spare

Just out of interest, I shot a wedding for a friend last weekend (I don't "do" weddings as part of my business, but this was my seventh... ) using the two Canon DSLRs - a 5D and a 1D Mk2 - and I ventured into ISO 1600 territory for the evening shots, including the first dance. The 5D performed unbelievably well to my surprise, while the 1D Mk2 was hot on it's heels, so my confidence in using such high ISOs has been boosted somewhat. Stephen routinely uses 1600 for his work (some recent prints he did for a conference on his 1D Mk2n just beggared belief; they were very clean), so I've had to concede that maybe it isn't the risky practice I'd previously convinced myself it was...

[Ian]

Re: High ISO - A must-read for digital users

Some of you might already have seen this, but this article over at DP Review discusses in some detail the subject of high ISOs in digital photography (more specifically relating to compact digicams) and also dispels some of the myths associated with it.

For those people who have little or no understanding of how the whole ISO thing works in the context of digital cameras, I think it makes for pretty interesting reading. Worth a look when you have five minutes spare

Just out of interest, I shot a wedding for a friend last weekend (I don't "do" weddings as part of my business, but this was my seventh... ) using the two Canon DSLRs - a 5D and a 1D Mk2 - and I ventured into ISO 1600 territory for the evening shots, including the first dance. The 5D performed unbelievably well to my surprise, while the 1D Mk2 was hot on it's heels, so my confidence in using such high ISOs has been boosted somewhat. Stephen routinely uses 1600 for his work (some recent prints he did for a conference on his 1D Mk2n just beggared belief; they were very clean), so I've had to concede that maybe it isn't the risky practice I'd previously convinced myself it was...

My experience is that you can get clean shots at almost any ISO (within some technical limits) but there will be a trade-off in terms of resolution. Noise reduction can be very effective, but the cost is detail retention.

For example, I have recently tested a 10MP camera that was out-performing the resolution test target I use at ISO 100, 200 and 400 (just), but by 800 the resolution was similar to that of a 6MP camera at ISO 100 and by ISO 1600 it was like a typical 4MP camera at ISO 100.

Noise reduction performed at the RAW level is even more effective.

Ian

[Ian]

Re: High ISO - A must-read for digital users

I was at my daughter's school this morning for a sharing assembly for the parents and an pile of musical instruments caught my eye. It was pretty dark and I was at the other side of the hall. So I thought I'd try ISO 1600 (using the new Olympus E-510, with moving sensor anti-shake). The focal length is about 128mm (in 'normalised' terms!) using the economy 40-150 kit lens (80-300 equivalent), shot at 1/30th, f/8.

There is some chroma noise, but it's quite well controlled. There is some softness compared with lower ISOs, but it's not disastrous by any means. Probably more critical is some evidence of light banding, which disappears at ISO 800.


But overall, this is a very usable image. It's also straight out of the camera in JPEG, with no processing at all except for re-sizing for online viewing and slight sharpening after the down-size.

A well-processed version of this image from the RAW file would be noticeably better.



I have to say that this exercise attempted with a two year old E-500 would have been far less successful as its high ISO noise performance is pretty poor in relative terms.


So the moral of the story is - don't be afraid of high ISO! Discover the actual limits of your camera It may mean the difference between grabbing a shot and missing it.


Ian