ISO noise advice sought.

[hab1966]

I was taking some pictures of my daughter in her cot the other night.

Camera was a Canon 30D with 50mmF1.4 lens. I was shooting at F1.4 and i turned the ISO all the way up to 1600 - my attempt to overcome the limited light in the room.

On my monitor, the pictures where noisy/grainy which I was expecting, due to (I believe) the high ISO figure for my camera.

What I'm unsure about is: If i had been able to shoot the exact same image on (say) a 7D with the ISO set to 1600, would the images have been similar in terms of noise? Would the number of pixels on the 7D make the noise less noticeable when viewed on my monitor?

Is there a correlation between ISO values and number of pixels/sensor size?

[4Lmike]

If you would have shot it on a 7D there would be much less noise.

You'll have to speak to someone else for a technical answer

[Gemm]

I think, in general, modern cameras/sensors tend to produce better high ISO performance. I haven't actually compared them myself, but this is my impression.

[tim-b]

Generally speaking, yes; better (esp. bigger) sensors and processors in the camera will result in less noise (grain). Pixel count not so much, in fact the lower number of pixels per sensor element(?) should actually give less noise (since there is a bigger physical area of the sensor to read the light per pixel that it outputs). But the newer cameras (i.e. 5Dmkii and 7D) control noise far better than older ones like the 30D, regardless of sensor size.

Before splashing out on a new body though, another option would be to just use a tripod, assuming your subject stays still enough. Then you can crank the ISO back down and use a longer exposure to compensate.

[Simpo Two]

What shuttter speed were you achieving with f1.4 and ISO1600? Could you have used a lower ISO? You should be able to handhold at least 1/60th and with practice 1/30th.

[toasty]

This might help. ISO1600 produces very little noise on the 7d.

http://www.dpreview.com/reviews/canoneos7d/page27....

[rhinochopig]

My 7d is noisey at high iso. I noticed because i don't like shooting at venues / indoors with a flash. I work round it by making a feature of noise and working in b&w. Better lens would allow a lower iso though, so i was told.

[hab1966]

Thanks for all the replies.

Tim-b: Whilst i am thinking of upgrading to a 7D it wasn't based on my experience detailed here. So until that day comes, i can try different ISO's, use a tripod etc.

Simpo Two: I was just experimenting with what the pics would look like with a higher ISO as i very rarely change it from 100. I must admit i just whacked it up to 1600 to see the results. I didnt do it in steps, which is what i should have done and found the optimum setting.

But it made me think of how a 'better' body would cope at the same speed.

So you can't compare ISO's across bodies unless they have the same sensor/electronics?

[rhinochopig]

hab1966 said:

Thanks for all the replies.

Tim-b: Whilst i am thinking of upgrading to a 7D it wasn't based on my experience detailed here. So until that day comes, i can try different ISO's, use a tripod etc.

Simpo Two: I was just experimenting with what the pics would look like with a higher ISO as i very rarely change it from 100. I must admit i just whacked it up to 1600 to see the results. I didnt do it in steps, which is what i should have done and found the optimum setting.

But it made me think of how a 'better' body would cope at the same speed.

So you can't compare ISO's across bodies unless they have the same sensor/electronics?

I was told the lens is the critical factor not the sensor or body, i.e. budget body with l series lens > pro body with cheap lens.

[tim-b]

rhinochopig said:

I was told the lens is the critical factor not the sensor or body, i.e. budget body with l series lens > pro body with cheap lens.

Hmm, I think sensor is the main factor....a good lens will usually be 'faster' though (meaning it has a bigger aperture, like f1.4) which means it lets in more light. In turn that means you can use a lower ISO to reduce the noise. So shooting with an f1.4 lens at ISO-1600 probably wouldn't have any less noise than shooting with a cheaper f4 lens at ISO-1600 (it's just that the f1.4 would allow you to use ISO-400 with the same shutter speed setting).

[AndWhyNot]

Aside from the specific relative performances of the 30D and 7D, don't confuse higher resolution with 'bigger' when it comes to comparing sensors and noise.

More pixels per unit of sensor area can contribute to more noise which is one reason why the 12mp full-frame sensor of the NIkon D3 is noticably less noisy than the 12mp DX sensor of the Nikon D300 (examples chosen to compare models of a similar age to eliminate factors of progress)

[RobDickinson]

hab1966 said:

What I'm unsure about is: If i had been able to shoot the exact same image on (say) a 7D with the ISO set to 1600, would the images have been similar in terms of noise?

No , the 7D absolutely kills the 30d for noise.

This is ISO 3200:


IMG_4972 by robjdickinson, on Flickr

I wont drag the lizard shot out again, I had a 350d (same sensor as the 30D) and the 7D has at least 2 stops on them and more detail ontop.

[RobDickinson]

But then a 430exII would help as much lol!

[rhinochopig]

RobDickinson said:

hab1966 said:

What I'm unsure about is: If i had been able to shoot the exact same image on (say) a 7D with the ISO set to 1600, would the images have been similar in terms of noise?

No , the 7D absolutely kills the 30d for noise.

This is ISO 3200:


IMG_4972 by robjdickinson, on Flickr

I wont drag the lizard shot out again, I had a 350d (same sensor as the 30D) and the 7D has at least 2 stops on them and more detail ontop.

Rob what lens did you use for that shot? I've got a 7D and my indoor sans flash pics seem much more noisy than your example. That said, I've only had the camera just over a month and am a total novice when it comes to digital SLRs so there is very very strong chance it's me not the lens/camera combo.

[RobDickinson]

That was shot with a sigma 50 f1.4 at f1.4,raw, and cleaned up in post with noise ninja.

[NJH]

Something else to think about when talking about ISO and noise is that on digital cameras you get less noise with more exposure. A simple example to exploit this is if the scene is fairly low contrast and you shoot raw your better off overexposing then rebalancing in post processing.
http://www.pekkapotka.com/journal/2011/12/20/expos...

[rhinochopig]

RobDickinson said:

That was shot with a sigma 50 f1.4 at f1.4,raw, and cleaned up in post with noise ninja.

Thanks.

Ah, so the lens would help a lot compared to the kit lens I have at the moment.

[Simpo Two]

rhinochopig said:

Ah, so the lens would help a lot compared to the kit lens I have at the moment.

Absolutely. The more light you can chuck in the front, the less high you need the ISO; the more options you have to play with. Ultimately it's a balance depending on what's most important - aperture (DOF), shutter speed (camera or subject movement) or ISO (noise).

[RobDickinson]

Yeah kit lens at 50mm is about f5.6 which is about 4 stops slower than the 50/1.4, or the difference between ISO 200 and 3200!

Another shot I took there was ISO 3200/f1.4 and 1/25th, not much natural light !

[Simpo Two]

Then again at f1.4 you can play 'spot the plane of focus'! Sometimes whilst possible, it's not the best option.

Damn these laws of physics... Freddy Flashgun is your saviour, as long as you remember the inverse law of thingy.

Another hot waterbottle of port please nurse.