7D - Grain and Noise - What are the primary factors?

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Pray tell-- How do you shoot at 80ISO with your 7D. Mine only goes to 100.

over expose and pull back in post for ISO 80

How ever there is no ISO 80 on any Canon DSLR just 50 and 100. The most important factor with noise or grain would be proper exposure and also exposing to the"right" just a bit to the right.





ISO 1600 Natural Light Canon 7D with Sigma 85mm F1.4 HSM








--
AustinLuker.com
7D-5DMKII-1DMKIV

wcrosman said:

wcrosman wrote:

Pray tell-- How do you shoot at 80ISO with your 7D. Mine only goes to 100.

--
T---
http://www.crosman.org
http://www.portfolio-shots.com

Click to expand...

wcrosman, you are correct! Thank you. Thought you were missing out? I would have too <ROFL>

Any thought on the grain and noise I posted about?



Best regards,

TVSTAFF

Austin_Luker said:

Austin_Luker wrote:

over expose and pull back in post for ISO 80

How ever there is no ISO 80 on any Canon DSLR just 50 and 100. The most important factor with noise or grain would be proper exposure and also exposing to the"right" just a bit to the right.


ISO 1600 Natural Light Canon 7D with Sigma 85mm F1.4 HSM

--
AustinLuker.com
7D-5DMKII-1DMKIV

Click to expand...

Austin_Luker,

Please help me here. When you say exposing to the right just a bit. How much of a bit? Just when the triangle goes from grey to white. Or... from grey to a color spike like blue or aqua?

I'M SO HAPPY YOU SPOKE OF THIS because I'm confused as to what the proper ETTR should be with respect to the triangle going from grey to a color and then white for what at times is too much exposure.

Can you please tell me what works best for you?

Thank you bringing up what is an important subject for me.

Best regards,

TVSTAFF

tvstaff said:

ISO 640 expected less noise. What am I doing wrong????



tvstaff wrote:

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Click to expand...

Here is an example at ISO 640. Where I expected less noise.

tvstaff said:

tvstaff wrote:

...
I'm confused as to what the proper ETTR should be with respect to the triangle going from grey to a color and then white for what at times is too much exposure.

...

Click to expand...

What "triangle" are refering to? Those in the histogram in LR or PS? If yes, then you are wrong. ETTR is not about pushing the histogram to the right in postprocessing. ETTR is about overexposing when shooting, just below the exposure whith which you would get burn-out zones (clipping white zones) in areas of interrest. The histogram of the original RAW file should be thus pushed to the right. Then, in postprocessing, you may pull exposure back to where you want. This process ensures minimal noise on any digital camera. So keep in mind: when postprocessing images which need increasing of digital exposure you will allways end up with more noise in the final image. And images which need less digital exposure will show less noise. Thus - avoid underexposing when shooting.

ETTR - how to do it? Well, this would be a long story. Just some hints here. You may start by overexposing in M mode then shoot, examine histogram, adjust exposure, shoot again until you get burned zones, then go back 1/3 stop with the exposure and make the final shot. Of course, this is very time-consuming. The real method is to shoot M and measure spot on certain zones in the frame, and this allows to obtain wanted exposure from the first shot. Experienced photographers get wanted exposure "computing" with their own brain (instead of letting the CPU of the camera to do the job) in less than 1 second! Further reading (google for this): M/spot, The Zone System.

And one more thing. When shooting RAW you see in the LCD of the camera a JPEG image adjusted with Picture Style parameters. Thus the histogram you may check is not the "real" one. In order to have a more realistic histogram you need a Picture Style based on Neutral or Faithful with Contrast to minimum. Image on LCD will look bad, but you will better know on the histogram wether you burned highlights or not. And yes, you need to shoot RAW. JPEG images are quite difficult to adjust in postprocessing.

To your ISO640 image:
Noise may be there from underexposing. But this is hard to tell unless you would upload the original RAW file. I mean, if you adjusted the image in post then the viewers do not know how bright or how dark was the original photo. Anyhow, looking at your image at 100% it seemes to me it was sharpened with a too large Radius. Those spokes in even areas usually come from sharpening with large radius, combined with large sharpening amount. A good procedure involves aditional masking of out-of-focus zones from sharpening. Easy to be done in LR.

--
[email protected]

fpix said:

fpix wrote:

fpix said:

tvstaff wrote:

...
I'm confused as to what the proper ETTR should be with respect to the triangle going from grey to a color and then white for what at times is too much exposure.

...

Click to expand...

What "triangle" are refering to? Those in the histogram in LR or PS? If yes, then you are wrong. ETTR is not about pushing the histogram to the right in postprocessing. ETTR is about overexposing when shooting, just below the exposure whith which you would get burn-out zones (clipping white zones) in areas of interrest. The histogram of the original RAW file should be thus pushed to the right. Then, in postprocessing, you may pull exposure back to where you want. This process ensures minimal noise on any digital camera. So keep in mind: when postprocessing images which need increasing of digital exposure you will allways end up with more noise in the final image. And images which need less digital exposure will show less noise. Thus - avoid underexposing when shooting.

ETTR - how to do it? Well, this would be a long story. Just some hints here. You may start by overexposing in M mode then shoot, examine histogram, adjust exposure, shoot again until you get burned zones, then go back 1/3 stop with the exposure and make the final shot. Of course, this is very time-consuming. The real method is to shoot M and measure spot on certain zones in the frame, and this allows to obtain wanted exposure from the first shot. Experienced photographers get wanted exposure "computing" with their own brain (instead of letting the CPU of the camera to do the job) in less than 1 second! Further reading (google for this): M/spot, The Zone System.

And one more thing. When shooting RAW you see in the LCD of the camera a JPEG image adjusted with Picture Style parameters. Thus the histogram you may check is not the "real" one. In order to have a more realistic histogram you need a Picture Style based on Neutral or Faithful with Contrast to minimum. Image on LCD will look bad, but you will better know on the histogram wether you burned highlights or not. And yes, you need to shoot RAW. JPEG images are quite difficult to adjust in postprocessing.

To your ISO640 image:
Noise may be there from underexposing. But this is hard to tell unless you would upload the original RAW file. I mean, if you adjusted the image in post then the viewers do not know how bright or how dark was the original photo. Anyhow, looking at your image at 100% it seemes to me it was sharpened with

Click to expand...

fpix said:

a too large Radius. Those spokes in even areas usually come from sharpening with large radius, combined with large sharpening amount. A good procedure involves aditional masking of out-of-focus zones from sharpening. Easy to be done in LR.

--
[email protected]

Click to expand...

FPIX,

Thank you for your detailed response. It was nice of you.

I'm sorry if I mixed up my LR post with shooting with the 7D.

1. Based on what you've said. Would it not be eaiser to just bracket each shot in 1/3 stops?

2. Am I to understand that setting the "contrast" when sooting does NOT effect the RAW file? I do not shoot in JPEG. My contrast is set to the mid-point and I always soot in faithful. My LCD is set to 50% to view the JPEG.

3. When the 7D is set to highlight over exposure in the LCD, should I be getting rid of EVERY bit of the flashing, then bracketing from that point? Would that be safer?

4. In post you say to use a smaller radius and brush just the areas I want to sharpen or demask?



Thank you very much

TVSTAFF

@1:
No. It's too complicated. See 3.

@2:
None PicStyle settings affect the RAW image. Consider these as start parameters for the JPEG converter. The RAW file has an embedded JPEG image which is shown in the LCD and which is processed in the camera according PicStyle. Make 2 photos from tripod, same exposure, same frame, once with Contrast = max, and second time with Contrast = min. Histogram of first image will be more to the right. But examining both RAWs in LR you will see that they are identical. That means that with Contrast larger than min you may see flashing highlights which actually are NOT burned.
Further, setting Sharpness to max helps you to evaluate correct focus in the field. Again this does NOT affect the RAW image.

@3:
Maybe. But just for you to get convinced that ETTR does the job. The real method is M/spot & Zone System.

@4:
No. In LR put radius = 1 (for correct focused images), amount = 30 ... 90, with ALT pressed vary masking and you will understand. Afterwards readjust amount to what you believe it is best. Make this on 100% view and check on 50% view. Don't be too aggressive. You should avoid spots and highlighted edges.

First.... Thank you.



I went to your site and your work is beautiful. I mean it. I'm really taken back by some of the work.



All the best to you and thank you again



TVSTAFF

Looks like classic over-sharpening to me.

You're welcome.
And thanks either.

tvstaff said:

tvstaff wrote:

tvstaff said:

ISO 640 expected less noise. What am I doing wrong????

tvstaff wrote:

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Click to expand...

Here is an example at ISO 640. Where I expected less noise.

Click to expand...

A couple of questions... is this a crop or full image? Secondly, did you pull the exposure up in post? If it's a crop, any noise you have will be enlarged and hence more visible. The tighter the crop, the worse it gets. If you pulled up the exposure, implying that it was somewhat underexposed to begin with, you'll end up with additional noise (the more underexposed the image, the worse the noise). The 7D is quite sensitive to underexposure, hence the excellent recommendations you're getting on using ETTR to minimize noise.

Austin_Luker said:

Austin_Luker wrote:

over expose and pull back in post for ISO 80

Click to expand...

So basically, you are overexposing and then trying to fix in PP? Am I understanding correctly?

What's the benefit over doing a "proper" exposure?

elfroggio said:

elfroggio wrote:

elfroggio said:

Austin_Luker wrote:

over expose and pull back in post for ISO 80

Click to expand...

So basically, you are overexposing and then trying to fix in PP? Am I understanding correctly?

What's the benefit over doing a "proper" exposure?

Click to expand...

Hi Syv,

The benefit is that the noise is now reduced by the amount that you pull the whole exposure back. That makes the subject matter properly exposed, but the noise is now further down into the black level and not visible.

elfroggio said:

elfroggio wrote:

elfroggio said:

Austin_Luker wrote:

over expose and pull back in post for ISO 80

Click to expand...

So basically, you are overexposing and then trying to fix in PP? Am I understanding correctly?

What's the benefit over doing a "proper" exposure?

Click to expand...

In the simplest sense, just think of a gray card or gray sheet over your subject, and set the camera to + 1/3 EC, and lock the exposure, and shoot the real subject without the gray facade. Then, in a converter, darken the image by 1/3 stop. You will have the same PRNU noise, but 1/6 stop less shot noise, and 1/3 stop less read noise, than if you had not exposed by an absolute +1/3 stop. Chances are, that unless you have a light source under the gray cover, or specular highlights, no highlights will clip. In fact, many DSLRs will allow you to use up to half the ISO (+1 EC) if metered with a true gray, without clipping non-specular or non-light-source highlights. Otherwise, highlight clipping of the RAW usually only occurs with poorly-chosen or ignored EC levels.

IOW, most DSLRs rate their ISOs very conservatively compared to slide film, or P&S compacts. Using the same highlight criterion as P&S cameras, most DSLRs would have have ISO ratings 20% to 50% lower than they do (for RAW exposure).

tvstaff said:

tvstaff wrote:

Here is an example at ISO 640. Where I expected less noise.

Click to expand...

Looks like excessive, unwarranted sharpening, on top of a texture-creating NR.

tvstaff said:

tvstaff wrote:

tvstaff said:

ISO 640 expected less noise. What am I doing wrong????

tvstaff wrote:

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Click to expand...

Here is an example at ISO 640. Where I expected less noise.

Click to expand...

Looking at the original size it looks like you've gone a bit far with the detail slider.

Jerry-astro said:

Jerry-astro wrote:

Jerry-astro said:

tvstaff wrote:

Jerry-astro said:

ISO 640 expected less noise. What am I doing wrong????

tvstaff wrote:

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Click to expand...

Here is an example at ISO 640. Where I expected less noise.

Click to expand...

A couple of questions... is this a crop or full image? Secondly, did you pull the exposure up in post? If it's a crop, any noise you have will be enlarged and hence more visible. The tighter the crop, the worse it gets. If you pulled up the exposure, implying that it was somewhat underexposed to begin with, you'll end up with additional noise (the more underexposed the image, the worse the noise). The 7D is quite sensitive to underexposure, hence the excellent recommendations you're getting on using ETTR to minimize noise.

Click to expand...

Yes this is a crop.
No I pulled it down

I'm getting a hat with ETTR on it!

tvstaff said:

tvstaff wrote:

tvstaff said:

Jerry-astro wrote:

tvstaff said:

tvstaff wrote:

tvstaff said:

ISO 640 expected less noise. What am I doing wrong????

tvstaff wrote:

At times I'll take a shot at 1600 ISO and the picture is flawless for a 5X7 or 8X10 print.

However, at times I'll shoot at 80 or 100 ISO and there is grain, noise.

Is there a SET rule for f-stop, ISO, Shutter speed and such that applies to "Noise"?

It seems pretty hit or miss for me at this point to emulate this issue. These issues seem to apply more with on camera flash and the 580EX II but also outdoors. This is why I feel I'm pushing the camera too far or not respecting the limits "I should be following". Just to be clear, I feel it's MY fault, user error not the 7D.

Thank you,

TVSTAFF

Click to expand...

Here is an example at ISO 640. Where I expected less noise.

Click to expand...

A couple of questions... is this a crop or full image? Secondly, did you pull the exposure up in post? If it's a crop, any noise you have will be enlarged and hence more visible. The tighter the crop, the worse it gets. If you pulled up the exposure, implying that it was somewhat underexposed to begin with, you'll end up with additional noise (the more underexposed the image, the worse the noise). The 7D is quite sensitive to underexposure, hence the excellent recommendations you're getting on using ETTR to minimize noise.

Click to expand...

Yes this is a crop.
No I pulled it down

I'm getting a hat with ETTR on it!

Click to expand...

How much of a crop ?