Is this normal noise for ISO 200?

The longer the exposure, the more electronic noise is introduced. There is probably a threshold where electronic noise, exceeds the random light noise. That is why in normal mode, the camera measures the electronic noise after exposure with the shutter closed past a certain exposure threshold, for the same length of time as the exposure, and attempts to compensate for it by substraction. The best way to reduce the light induced noise is to overexpose up to the clipping point, hence increasing the numbers of photons hitting the sensor, or take multiple takes and combine them into one.

--
Roger

Well,

the noise on your photo (I mean blue skies) is perfectly normal. You photo is not underexposed at all. It is obvious when open Raw.

Blue skies are always noisy. noise is mostly luma and easy to remove. I think you have nothing to worry about

bclaff said:

rjensen11 said:

bclaff said:

I think that came out really well considering how underexposed the image was.

From running RawDigger on the ORF:



It's a 12-bit file so values should go up nearly 4000.
I'm wondering why this happened in Aperture mode. (1/2000s seems too fast)

Click to expand...

Here is the histogram from LR. I'm not sure why it should be an order of magnitude higher that what was captured (4000 instead of 400).



This is an exposure I would consider OK, but I'm a newbie when it comes to this.

It was a beautiful, sunny day so I didn't think the 1/2000 was unusual. Maybe my metering (ESP) wasn't the right setting? I was focused on the bird.

Thanks for your help.

Click to expand...

That looks like the JPEG histogram. The RawDigger one is from the raw and more appropriate for judging exposure.

Still puzzled by the underexposure but I'm not an expert on Olympus metering etc.

--
Bill ( Your trusted source for independent sensor data at PhotonsToPhotos )

Click to expand...

It is definitely from the raw file-sharing bit the jpeg.

Even zoomed in it looks normal.

Better question is; if this is expected noise for f/4 1/2000... and yes as the image does not look like the camera malfunctioned. Image noisiness is primarily due to low exposure and not high ISO. However, what high ISO sometimes do is that that it sets the AE for lower exposure (F# and/or SS).

Blue Northern sky is about a +1 EV brighter than the middle gray; so based on sunny 16, the nominal exposure would have been f/16 1/60 at ISO125.

Since f/4 1/2000 is equivalent exposure of f/16 1/125, the image may be about a stop under exposed, which explains why ISO is set at 200 (makes the image look a bit brighter). I realize ISO200 is the base ISO. So the camera chose AE that is about a stop under exposure.

So technically, you are getting more noise than if you could have set to ISO125 and shoot it at f/4 1/1000. Or dialed in +1 EC to increase the exposure to f/4 1/1000 ISO200.

The image (sky) would look brighter (less saturated blue) but less noisy. And the sky could be made look more saturated in PP; else apply NR to the image to reduce the noise as it's shot with 1/2000 SS.

If you are going "huh", it's not your fault... This is a complicated subject and I am not best with my explanation...

Good luck.

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

rjensen11 said:

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

Click to expand...

Just remember, the noise doesn't come from the ISO setting, it comes from not gathering enough light.

bclaff said:

rjensen11 said:

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

Click to expand...

Just remember, the noise doesn't come from the ISO setting, it comes from not gathering enough light.

Click to expand...

I did not do a good job of explaining that...

bclaff said:

rjensen11 said:

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

Click to expand...

Just remember, the noise doesn't come from the ISO setting, it comes from not gathering enough light.

Click to expand...

OK - it's starting to make sense to me now (I'm sort of dense). The picture I posted last week was underexposed, so I had bumped up the exposure quite a bit. That is probably why someone said I had a lot of noise. If I had properly exposed it I would not have had the noise issue.

I'm going back to the beach tomorrow. Maybe I'll do better!

Indirectly I mean..

If you did not post process the image or used strong jpeg setting to alter the image.

More precisely:

brightness (of one pixel) = exposure + ISO

You need only to know the ISO to assess the exposure, and the jpeg image is enough (ISO standard is based on JPEG..). You do no need to know the aperture, shutter speed, nor the exposure compensation

So this is perfectly legitimate to ask if this level of noise is expected at ISO200.

Christof21 said:

I

So this is perfectly legitimate to ask if this level of noise is expected at ISO200.

Click to expand...

That is true only if the exposure is known to be metered correctly to ISO 200. Even then, if the scene varies considerably in brightness, it is necessary to know how the metering was done (spot metering on a particular spot in the scene, centre-weighted, etc.).

Tom Axford said:

Christof21 said:

I

So this is perfectly legitimate to ask if this level of noise is expected at ISO200.

Click to expand...

That is true only if the exposure is known to be metered correctly to ISO 200. Even then, if the scene varies considerably in brightness, it is necessary to know how the metering was done (spot metering on a particular spot in the scene, centre-weighted, etc.).

Click to expand...

Not at all, you don't have to know how the metering was done

Again brightness = exposure + ISO

A pixel which has more brightness receives more exposure, simple.

rjensen11 said:

bclaff said:

rjensen11 said:

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

Click to expand...

Just remember, the noise doesn't come from the ISO setting, it comes from not gathering enough light.

Click to expand...

OK - it's starting to make sense to me now (I'm sort of dense). The picture I posted last week was underexposed, so I had bumped up the exposure quite a bit. That is probably why someone said I had a lot of noise. If I had properly exposed it I would not have had the noise issue.

I'm going back to the beach tomorrow. Maybe I'll do better!

Click to expand...

Just download a trial of dxo-photolab 2 and stop worrying about noise. This is ooc jpg vs raw at ISO 25,600. You will also get better lens correction which is why you can see more yellow letters on the book spine.





Ian

Christof21 said:

Tom Axford said:

Christof21 said:

I

So this is perfectly legitimate to ask if this level of noise is expected at ISO200.

Click to expand...

That is true only if the exposure is known to be metered correctly to ISO 200. Even then, if the scene varies considerably in brightness, it is necessary to know how the metering was done (spot metering on a particular spot in the scene, centre-weighted, etc.).

Click to expand...

Not at all, you don't have to know how the metering was done

Again brightness = exposure + ISO

A pixel which has more brightness receives more exposure, simple.

Click to expand...

Of course, if you know the exposure (including knowing how bright the scene was), then there is no need to know anything about the metering. And, to a first approximation, you don't need to know about the ISO either.

I was assuming that the OP, like most of us, did not know exactly how bright the scene was in absolute terms, so he did not know the actual exposure (meaning the amount of light captured per unit area of the sensor).

Christof21 said:

Tom Axford said:

Christof21 said:

I

So this is perfectly legitimate to ask if this level of noise is expected at ISO200.

Click to expand...

That is true only if the exposure is known to be metered correctly to ISO 200. Even then, if the scene varies considerably in brightness, it is necessary to know how the metering was done (spot metering on a particular spot in the scene, centre-weighted, etc.).

Click to expand...

Not at all, you don't have to know how the metering was done

Again brightness = exposure + ISO

A pixel which has more brightness receives more exposure, simple. - bold added

Click to expand...

It could have received more ISO rather than more exposure.

If the shot was made at f/4 1/2000 and ISO 400, image noisiness still about the same as ISO200; however, if it's shot at f/4 1/10000 ISO200, it would be less noisy.

rjensen11 said:

bclaff said:

rjensen11 said:

mostlyboringphotog said:

rjensen11 said:

ToxicTabasco said:

Even zoomed in it looks normal.

Click to expand...

Thanks for confirming - I never thought I had a problem until someone said I had a lot of noise in a picture I posted on this site. It was a long-ish exposure (1.3 sec), so that may have been the source of the noise.

Click to expand...

My turn to go "huh". Unless there is another shot, the OP photo exif shows 1/2000 shutter speed.

Click to expand...

Sorry for the confusion - this is the picture I posted last week that someone said I had a lot of noise for ISO 200: https://www.dpreview.com/forums/post/62470750.

That was the source my questioning what is the normal amount of noise for ISO 200.

Click to expand...

Just remember, the noise doesn't come from the ISO setting, it comes from not gathering enough light.

Click to expand...

OK - it's starting to make sense to me now (I'm sort of dense). The picture I posted last week was underexposed, so I had bumped up the exposure quite a bit.

Click to expand...

Do you mean brightening in PP; typically the "sliders" may be labeled "exposure", but the image exposure as defined in "lux-second" cannot be changed. Brightening in PP is similar to bumping up ISO (and same as "expanded ISO") but in camera higher ISO usually works better than brightening in PP.

MtnView said:

That is probably why someone said I had a lot of noise. If I had properly exposed it I would not have had the noise issue.

Click to expand...

I'm dense too ;-) but I think I got it now.

MtnView said:

I'm going back to the beach tomorrow. Maybe I'll do better!

Click to expand...

Yandrosxx said:

Yandrosxx said:

I've had my em1m2 for a while, and while it was a little noisier than my 7dm2, I figured this was normal for a m43 sensor.

Click to expand...

Per Imaging Resource it outperforms the 7D Mark II in noise performance. 1300 iso versus 1000. Should be producing cleaner files.

Click to expand...

I don't think that any other source supports that. IR's test methodology can be quite loose, particularly, I think they use the camera's exposure meter to set exposure.

bclaff said:

I think that came out really well considering how underexposed the image was.

From running RawDigger on the ORF:



It's a 12-bit file so values should go up nearly 4000.
I'm wondering why this happened in Aperture mode. (1/2000s seems too fast)

Click to expand...

Given the amount of raw headroom Olympus leaves on this camera, an exposure set by the camera exposure meter won't go above about 2000. In this case, there''s nothing particularly bright in the image, so where it is, is quite believable given the exposure meter calibration. So far as Olympus is concerned, it isn't 'underexposed'.

--
Ride easy, William.
Bob