Pages: [1]   Go Down

Author Topic: HowTo? Best practice for default NR values based on ISO with PV2010/PV2012?  (Read 17823 times)

l_d_allan

  • Full Member
  • ***
  • Offline Offline
  • Posts: 208
    • Berean photos

I'm unclear about setting default values for the Noise Reduction sliders in ACR for PV2010 and PV2012.

I have the following selected
x Make defaults specific to camera serial number
x Make defaults specific to camera ISO setting

With the above, the defaults can be different for my Canon 5d2 and T3i. Also, they can be different for each ISO for each camera. OK so far?

However, the ACR as-installed defaults for PV2010 and PV2012 seems to use the same NR slider values, regardless of ISO. IIRC, Luminance is 0 / OFF / OFF, and Color is 25 / 50. Does that mean the same NR parameters are applied to an image shot at ISO 100 as ISO 6400?  Is Luminance NR always OFF by default?

I've tweaked the default NR slider values to have increasing values for Luminance, Luminance Contrast, and Color as ISO increases. I've left Luminance Detail and Color Detail sliders at the default of 50.

For example, for my 5d2, here are some NR default settings for several ISO's:
50       = 5,50,5,5,50
100     = 10,50,10,10,50
125     = 13,50,13,13,50
200     = 20,50,20,20,50
400     = 30,50,30,30,50
800     = 40,50,40,40,50
1600   = 50,50,50,50,50
3200   = 60,50,60,60,50
6400   = 70,50,70,70,50
12800 = 80,50,80,80,50
25600 = 90,50,90,90,50
etc, with intermediate values for in-between ISO's.

I am ignorant whether the above is appropriate, or flawed. My uninformed speculation is that I'm applying too much default NR to higher ISO images.

I realize that the appropriate NR slider values will differ, depending on the specific image. However, I'd like to start with appropriate defaults, and go from there.

My understanding is the same applies to Lightroom.  Or not?
Logged
retired in Colorado Springs, CO, USA ... hobby'ist with mostly Canon gear

Schewe

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 6229
    • http:www.schewephoto.com

However, the ACR as-installed defaults for PV2010 and PV2012 seems to use the same NR slider values, regardless of ISO. IIRC, Luminance is 0 / OFF / OFF, and Color is 25 / 50. Does that mean the same NR parameters are applied to an image shot at ISO 100 as ISO 6400?  Is Luminance NR always OFF by default?

As far as I know, there were no changes in NR between PV 2010 & 2012…and yes, by default, luminance NR is off by default…it is processor intensive so Thomas didn't want to add NR by default and make the user select their own choices. You can modify your ACR/LR defaults as you please. PV 2003 had a slight bit on NR built in (even though the amount was still set at 0). The sharpening and noise reduction was changed considerably for PV 2010.

Color NR on the other had is on by default and as far as I know, the color NR is dependent on ISO (but I might be wrong about that–Eric would know for sure). As far as your settings for the various ISOs, it really all depends on your sensor and it's noise signature…without knowing what camera you are using, it's hard to make any judgements about your settings.

Also note that image sharpening and noise reduction are really two sides of the same coin. If you use an aggressive sharpening with a high detail slider adjustment, you'll need to tune the luminance NR to work with your sharpening.
Logged

eliedinur

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 328

A couple comments about your proposed list of defaults for the 5D2:
1. The increase of Luma NR amount by 10 for each doubling of ISO seems arbitrary and unjustified by empirical inspection. The increase in amount may or may not be linear (despite the linear scale), but the increase in noise is definitely not linear.
2. Why use ISO 125, which is pushed from ISO 100 and because of this actually has more noise than ISO 200? Because of this your default for that ISO seems inappropriate. If you want an intermediate ISO, 160 would be a better choice since it is pulled from 200 and therefore has low noise although there is also a slight loss of DR because of the increased unused overhead. But if you shoot Raw this is unnecessary since you can shoot ISO 200 to the right and do your own pull better in ACR.
3. Similarly, all the ISOs above 3200 are digital pushes that you can probably do better in ACR, especially since the camera push is linear but in ACR you can customize it - more in one tonal range and less in another. Of course that will also mean customizing your NR to match. The only real justification for a Raw shooter to set ISOs above 3200 is if you are using Live View with exposure simulation.
4. Adobe says that the Color NR default of 25 will be good for most photos, needing to be increased only for very high ISOs.
« Last Edit: November 06, 2013, 06:23:17 pm by elied »
Logged
Roll over Ed Weston,
Tell Ansel Adams th

l_d_allan

  • Full Member
  • ***
  • Offline Offline
  • Posts: 208
    • Berean photos

A couple comments about your proposed list of defaults for the 5D2:
1. The increase of Luma NR amount by 10 for each doubling of ISO seems arbitrary and unjustified by empirical inspection.

Agree. That's why I asked about appropriate values as defaults. Or is the ACR default of no luminance NR and 25/50 color NR appropriate for all ISO's and all cameras?
Logged
retired in Colorado Springs, CO, USA ... hobby'ist with mostly Canon gear

eliedinur

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 328

Agree. That's why I asked about appropriate values as defaults. Or is the ACR default of no luminance NR and 25/50 color NR appropriate for all ISO's and all cameras?
Every camera is different both in the amount and type of noise for any given ISO and for the curve along which the noise increases as ISO increases. Moreover, noise is affected by the other editing you do and also by image content - smooth areas show noise more and highly textured areas conceal it. So I don't think any single value, whether 0 or otherwise, can be "one size fits all". Color NR may do different operations for the same 25 setting according to model and ISO, but the same does not seem to be true of Luma NR.
Logged
Roll over Ed Weston,
Tell Ansel Adams th
Pages: [1]   Go Up