In camera noise reduction

[Gerry]

Does anyone here have noise reduction active in their camera menu for night shots/high ISO? I tried it recently but wasn't really impressed, either with the time taken to do the reduction or the results. I'd be interested to here about the experience from others.

[Ian]

Do you mean long exposure noise reduction? This isn't really the same software or other noise grain removal. It's the camera's way of removing hot pixels on the sensor. Once your exposure has been made, a second of the same duration is made but with the shutter closed.The camera looks at the second exposure and where it finds hot pixels it will blend them out in the 'real' shot - it's also called dark frame subtraction. It works independently of the ISO setting used.

Ian

[Graham_of_Rainham]

I use the Olympus Workspace AI for any Noise Reduction, for me it works very well

[Gerry]

Do you mean long exposure noise reduction? This isn't really the same software or other noise grain removal. It's the camera's way of removing hot pixels on the sensor. Once your exposure has been made, a second of the same duration is made but with the shutter closed.The camera looks at the second exposure and where it finds hot pixels it will blend them out in the 'real' shot - it's also called dark frame subtraction. It works independently of the ISO setting used.

Ian

In the E-M! iii menu E1 (page 191 and 192 of the user manual) there are 2 settings for noise.

The first one "Noise Filter" states: Choose the amount of noise reduction performed at high ISO sensitivities.

This would imply that whatever is being done to the image file is independent of the ISO used.

The second one "Noise Reduct." lists:

This function reduces the noise that is generated during long exposures.
• The time required for noise reduction is shown in the display.
• [Off] is selected automatically during sequential shooting.
• This function may not work effectively with some shooting conditions or subjects.
[Auto]: Noise reduction is performed at slow shutter speeds, or when the internal temperature of the camera has risen.
[On]: Noise reduction is performed with every shot.
[Off]: Noise reduction off.

Implying that the action is somewhat similar to running the file through something like Topaz.

[Ian]

Yes, this is why I asked which option you were referring to. Noise Reduction is primarily for long exposures and uses dark frame subtraction and does double the initial exposure time. It has no effect on general noise grain, just relatively few pixels that show up in longer exposures.

The Noise Filter reduces noise grain but only for in-camera JPEG images - it has no effect on RAW files. However, RAW files will retain the setting tag and if you then process in OM Workspace, the noise filter will be applied there. The noise filter works at all ISO settings and does not slow the camera down. The noise filter is a relatively simple function and has been around since the original E-1. One potential cost is resolution/sharpness, so I recommend (if you are shooting JPEGs) to limit it to a low setting.

Ian

[Gerry]

Thank you Ian. I shoot RAW and I'll just keep both options turned off.

[Ian]

For long exposures, I feel Noise Reduction is worth the wait.

Ian

[Gerry]

I'll take a few test shots with and without and see how they compare.