Understanding Noise

[cjcampbellphoto]

Hi Canon Community,

I'm an amateur photographer looking to improve my skills and I'm struggling in low light situations.  I recently took some photos of my friends using a Canon 7D (the oldest model) and an EF 100-400mm f4.5-5.6L IS USM with the settings of:
ISO250 at 100mm f/4.5 and 1/125 sec.  The picture shows up with a TON of grain and I'm confused. The ISO isn't that high at all.  I bumped up the exposure by +2 in Lightroom just to show how much grain is in the photo:

Any tips would be greatly appreciated!

Best,

CJ

[cjcampbellphoto]

I'm an amateur photographer looking to improve my skills and I'm struggling in low light situations.  I recently took some photos of my friends using a Canon 7D (the oldest model) and an EF 100-400mm f4.5-5.6L IS USM with the settings of:
ISO250 at 100mm f/4.5 and 1/125 sec.  The picture shows up with a TON of grain and I'm confused. The ISO isn't that high at all.  I bumped up the exposure by +2 in Lightroom just to show how much grain is in the photo:

Any tips would be greatly appreciated!

Best,

CJ

[ebiggs1]

" Noise will certainly occur when you are underexposed and boost exposure during PP."

Absolutely but I don't think what he is seeing or I see is noise.  It looks more like resolution of the lens which was not the best for that shot. Exposure is a problem certainly.

[Waddizzle]

---

@ebiggs1 wrote:

" Noise will certainly occur when you are underexposed and boost exposure during PP."

Absolutely but I don't think what he is seeing or I see is noise.  It looks more like resolution of the lens which was not the best for that shot. Exposure is a problem certainly.

---

I did not see significant noise, either.  It might be the lens.  It might be the APS-C sensor.  The original shot may have been off, but I think the photo does not descend to the level of bad.  I think it is pretty good.

[Tronhard]

I agree about the noise.   I had been looking on a monitor that was not my own or up to scratch.  Now that I have had a chance to see it under better conditions I think that the image is a bit under exposed but not terribly noisy.

I am surprised that the lens would be the culprit as the 100-400 has always been regarded in its two versions as a bad lens - certainly that has not been my expeience...

[cjcampbellphoto]

Thank you! I was looking on a monitor that wasn’t so great either and I think that’s where the major problem was too

[ebiggs1]

"I am surprised that the lens would be the culprit as the 100-400 has always been regarded in its two versions as a bad lens ..."

Having owned the first version and using a borrowed 2nd version, IMHO, the second is very much a better lens. Version 1 is not one of the best lenses I have ever used. Don't get me wrong, it is OK but just average.

The single reason I don't buy version 2 is it doesn't have 401 to 600mm.

Again, IMHO, I don't see either as indoor, up close, lenses and that is what the OP is seeing.  There are better choices. Shoot to the right is correct.

[cjcampbellphoto]

Thank you!

[cjcampbellphoto]

I admit I was editing on a large monitor that isn't necessarily built for it so I believe the accentuation of noise came from the large 4K monitor.  I would like to ask how I can determine the best lenses for clarity. Is it strictly the glass of the lens? 

[jrhoffman75]

Welcome to the forum CJ.

I opened your image in Lightroom and lowered the exposure by -2. Here is the image.

As you can see from the istogram it is significantly underexposed.

Then I increased the exposure until a small specular highlight on her galsses just started to give a highlight warning.  Here is the image.

AI consider this a well exposed image for the subject - it is +3.45 over your original.

Were you letting camera select the exposure or were you in manual mode?

The settings you presented are an EV of 12 2/3.

The daylight basic setting of Sunny 16 would be an EV of 14 2/3. (f/16, ISO 100, shutter 1/100).

An interior room, that you described as dark, would generally be darker than two stops below daylight.

What was the metering setting in the camera?

To me there is no obvious reason why the camera shouldn't give you a proper exposure in Program AE in that setting. Then you could refine it. The camera would use program shift - if you were to decrease the ISO to lessen noise then the shutter speed would slow down. IS on the lens could help with camera shake.

The jpeg you posted is only 1.2MB. I personally wouldn't be making any judgements about lens quality from enlarging that image. 

[ebiggs1]

"I personally wouldn't be making any judgements about lens quality from enlarging that image"

I would!  There are only two ways to go here is it noise or resolution.  We mostly agree there isn't any, too very little, noise in the photo.

Now, probably not the best use of a 100-400mm zoom.  That and a small exposure error add up to what the OP got. Actually not too bad considering and 100% fixable in LR/PS.

[cjcampbellphoto]

Forgive me, as being a new photographer, a lot of this is a bit over my head!

I was shooting in manual mode. What is program shift?