Why is my 6D Long exp. noise reduction counterproductive! (help judge pics inside)

I was planning to turn it ON for my coming milky way photography without a tracking mount.
I was curious how much the 'long exp. noise reduction' reduce noise at very high iso.
I did a simple test and it didn't come out as expected. Why?

Using LR4, I increase exposure by 1.45 to make it more obvious. The test has been repeated with very consistent result.

Turning long exp. noise reduction on, lens cap on and covering the VF, I notice:
-it does reduce big white pixel (that's hot pixels, isn't it?). good.
-but it introduces more 'fine' 'random' noise
-the histogram shifted to the right, it means more noise.

Turned on:

long exp noise reduction is for in camera JPEG only.

hes gone wrote in post #15769323
=he's gone;15769323]long exp noise reduction is for in camera JPEG only.

Hi, thanks for helping. However, it applies to RAW. I'm sure about that. There are countless of threads that support it. Also, if it did not apply to RAW files, how do you explain the differences in my test?

hes gone wrote in post #15769323
=he's gone;15769323]long exp noise reduction is for in camera JPEG only.

Are you sure about that?

I don't think it helps if you're just taking a pic of the lens cap, since the second exposure is one with the shutter closed. You're trying to get the the camera to reduce background noise with background noise.

caoko wrote in post #15769381
I don't think it helps if you're just taking a pic of the lens cap, since the second exposure is one with the shutter closed. You're trying to get the the camera to reduce background noise with background noise.

i get your point. but it doesnt hurt to shoot a 'black' image its easier to pixel peep too.

Lol what you are doing is basically driving with your eyes closed and wondering why are you hitting things. Your camera is not design to work with zero light exposure. Go in to a pitch black room and do your test and I can almost guarantee you that you'll have a very low noise picture.

learncanon wrote in post #15769399
i get your point. but it doesnt hurt to shoot a 'black' image its easier to pixel peep too.

Just out of curiosity - what previous model Canon DSLRs have you used? I ask this because I started in digital with an original Digital Rebel/300D - it was horribly noisy in a lot of instances above 400 ISO. I have noticed a lot of forum users quibbling at the "shortcomings" of current model DSLR bodies, and it always makes me wonder what their past experience in DSLR's was.

I currently have 5Dm2's and they are so clean - I have never once had to be concerned about extreme ISO settings when shooting low light stuff at weddings or street/travel stuff at night with no tripod... The tech has advanced so far that its just not a limiting factor in real world shooting anymore IMO. Even when viewed at 100% (which is also totally never going to happen once it leaves your editing software)

learncanon wrote in post #15769343
Hi, thanks for helping. However, it applies to RAW. I'm sure about that. There are countless of threads that support it. Also, if it did not apply to RAW files, how do you explain the differences in my test?

krb wrote in post #15769352
Are you sure about that?

no, i'm not sure about that! LOL

carry on.


cheers!

awesomeshots wrote in post #15769404
Lol what you are doing is basically driving with your eyes closed and wondering why are you hitting things. Your camera is not design to work with zero light exposure. Go in to a pitch black room and do your test and I can almost guarantee you that you'll have a very low noise picture.

Hi, i have done shooting in my pitch black room and getting similar result. less hotpixel but more overall noise. a user at canonrumour forum confirms this result, unfortunately.

could you post up any samples? thanks!

Andrushka wrote in post #15769441
Just out of curiosity - what previous model Canon DSLRs have you used? I ask this because I started in digital with an original Digital Rebel/300D - it was horribly noisy in a lot of instances above 400 ISO. I have noticed a lot of forum users quibbling at the "shortcomings" of current model DSLR bodies, and it always makes me wonder what their past experience in DSLR's was.

I currently have 5Dm2's and they are so clean - I have never once had to be concerned about extreme ISO settings when shooting low light stuff at weddings or street/travel stuff at night with no tripod... The tech has advanced so far that its just not a limiting factor in real world shooting anymore IMO. Even when viewed at 100% (which is also totally never going to happen once it leaves your editing software)

550D. yes, it does not affect normal shooting but astro-photography (particularly the milky way, we need to photograph really dark skies at iso 1600-6400 before stars start to trail). Yes, modern cameras are really good at iso performance and no doubt about that. Still, I welcome any techniques to reduce noise further so that I can have more room to play with aperture,shutter speed and post-processing.

Anyway, I'm asking why Long exp. noise reduction is giving more overall noise. not discussing how good modern cameras are at high iso.

The website you shared your files asks me to sign-up to download them. It even asks me to install some shady *.exe

You should use something that sucks less.

so i did a little poking around, because there was some thought in the back of my mind about RAW files and in camera noise reduction.

I found was this regarding High ISO noise reduction.

http://www.learn.usa.c​anon.com …e_reduction_art​icle.shtml

the similar article on long exposure NR doesn't go into that much detail regarding RAW.

http://www.learn.usa.c​anon.com …exposure_landsc​apes.shtml

hes gone wrote in post #15769525
=he's gone;15769525]so i did a little poking around, because there was some thought in the back of my mind about RAW files and in camera noise reduction.

I found was this regarding High ISO noise reduction.

http://www.learn.usa.c​anon.com …e_reduction_art​icle.shtml

the similar article on long exposure NR doesn't go into that much detail regarding RAW.

http://www.learn.usa.c​anon.com …exposure_landsc​apes.shtml

nice read. but High ISO noise reduction is a different thing from Long exp. Noise Reduction.
Also, if it is true that adobe LR4 ignores Long exp. Noise Reduction, it does not explain why it is producing more noise so consistently.

just saw another test with 550D that supports my result. jump to the 3rd image

http://www.betelgeuse-observatory.com/?p=302