M240 Color Test ... Oh, oh!

[AlanJW]

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going back to the original topic about the colour shifts in the bag shown in the oringal post; are there any lightroom editing tips that can be utilized to minimize the colour shifts in images I already have? in the meantime, i'm on my way to purchase some 486 UV IR cut filters.

 

Sometimes you can desaturate magenta. Depends on what else in your scene of course. I prefer this way unless there are lots of other magenta areas as it does not change the color balance.

[Guest]

going back to the original topic about the colour shifts in the bag shown in the oringal post; are there any lightroom editing tips that can be utilized to minimize the colour shifts in images I already have? in the meantime, i'm on my way to purchase some 486 UV IR cut filters.

 

I prefer to use the RGB curves in PS to pull down the R curve in areas that correspond to the offensive magenta....you can save this as a custom curve apply it to like exposures rather than repeating it ad infinitum. Occasionally you will need to adjust G and B curves to fine tune

the process.

 

Bob

[pieterpronk]

I'm planning to shoot an event this weekend. It's indoors with typical yellow (tungsten?) lighting.

 

Normally I would just use a grey card and shoot. I typically use a UV filter for protection (easier in crowded spaces imo). Would it be better to use my old M8 uv-ir filter?

 

 

Sent from my GT-I9300 using Tapatalk

[01af]

I prefer to use the RGB curves in Photoshop to pull down the R curve in areas that correspond to the offensive magenta ... you can save this as a custom curve apply it to like exposures rather than repeating it ad infinitum. Occasionally you will need to adjust G and B curves to fine-tune the process.

Are you aware that you can do the same also in Lightroom or Camera Raw? No Photoshop required.

[jaapv]

I prefer to use the RGB curves in PS to pull down the R curve in areas that correspond to the offensive magenta....you can save this as a custom curve apply it to like exposures rather than repeating it ad infinitum. Occasionally you will need to adjust G and B curves to fine tune

the process.

 

Bob

I don't think a custom curve (or Droplet or Action) will work efficiently - the effect varies with the light and subject.

Adjusting the A and B curves in LAB is even more effective.

[jaapv]

I'm planning to shoot an event this weekend. It's indoors with typical yellow (tungsten?) lighting.

 

Normally I would just use a grey card and shoot. I typically use a UV filter for protection (easier in crowded spaces imo). Would it be better to use my old M8 uv-ir filter?

 

 

Sent from my GT-I9300 using Tapatalk

I use the grey card setting of the camera with an Expodisk. And yes, by all means use the IR filter, if you can avoid reflections.

[mirekti]

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Is there a new firmware comming up soon? Are there any beta testers, or the update is on hold for now?

 

I took these photos in the room without any other light source except for the one that comes through the window.

 

The first photo was taken with an iPhone, a second one is out of camera. I know this is not the way one should perform the tests, and maybe my monitor isn't calibrated, however, the difference is so obvious and iPhone is much more closer to what I see with my eyes that this really makes me angry.

In order to get the colors match the scene or get as close as iPhone did, I had to play not only with the temperature slider, but with a half dozen HSL sliders too.

The third photo is very close to what the colors really look like.

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[farnz]

The second looks a little underexposed compared to the first one on my screen. And the white balance looks a bit off: the whites look blue-grey

 

Pete.

[Rick]

I prefer to use the RGB curves in PS to pull down the R curve in areas that correspond to the offensive magenta....you can save this as a custom curve apply it to like exposures rather than repeating it ad infinitum. Occasionally you will need to adjust G and B curves to fine tune

the process.

 

Bob

 

Bob - If, you start out in LR and want to save a trip to PS, try the "Tone Curves" section in the LR develop module. It is a lot like PS.

 

Use RGB and select Red. Use the eye dropper-like curser and select the part of the picture that has the magenta. Pull the curve down. Go back to WB and adjust Temp and Tint to adjust G and B globally. (look for a black color to center the curser on while you balance out the RGB with the Tint/Color sliders)

 

Here is an example. You can see the RGB Curves on the right and above the value of the RGB of the black square under the Histogram. Pretty close, maybe some shadow or fall-off on the left still, but you can see how few steps are used under History.

 

 

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[dwbell]

The green curve is greener above the line and more magenta below the line. Wouldn't that be the logical place to remove magenta?

[Rick]

The green curve is greener above the line and more magenta below the line. Wouldn't that be the logical place to remove magenta?

 

No.

[jaapv]

+1 Green and magenta are opposite colors.The curve is always a balance between the two.

[dwbell]

No.

 

You er, wanna expand on that?

[thighslapper]

Knowing Rick it would be NO! NO! followed by some incendiary expletives

 

Just don't ask......

[dwbell]

Knowing Rick it would be NO! NO! followed by some incendiary expletives

 

Just don't ask......

 

Haha! Indeed.

 

Knowing Rick there will actually be a perfectly rational and intelligent reason behind not going the green curve route. He'll just want some sport in explaining it to us!

[Rick]

Haha! Indeed.

 

Knowing Rick there will actually be a perfectly rational and intelligent reason behind not going the green curve route. He'll just want some sport in explaining it to us!

 

NO! NO! NO!

 

Dweebs, the answer to your question of why you don't add green is that it is easier to subtarct red.

 

The reason it easier to subtract red is multifactorial. First, the photo I used (you probably have a copy of it on your computer) shows more red on the left side. This example shows too much red not too much green. So, it is first of all easier to identify the red tone (because it is obvious). All you have to do is use the tone color dropper and pick a red color off the table on the left. If, you wanted to add green... what tone of green are you going to pick and from where? You could do it, but why make it difficult.

 

Next, you always want to mix down. When using the Tone Curves it is almost always advantages for many reasons to subtract color... or mix down. You never hear the phrase mix-up? You always do the mix down. If, you were to start adding color (green) you are mixing up. Eventually, you run into the upper limit of the dynamic range and you lose the mix. Always mix down and pull the noise floor down. Once the color channels are balanced the way you want them you can globally mix up the whole photo with all channels if needed.

 

So, once I chose the red color tone I wanted using the dropper-like tool in curves... I pulled the curve down and got the best color balance I could using the Red Channel curve point the dropper selected off the red portion of the table.

 

Then, I went back up to the WB module and used Color and Tint to balance the Blue and Green globally.

 

Lastly, I am on my MacAir (poor color screen). So, I then used the black color swatch on the color card to tweak the balance of the RGB channels. With my curser over the black swatch, I adjusted the WB Color then the WB Tint to get the RGB values under the Histogram to be about equal.

 

Most always - Identify the ofending color and mix color tones

down

not up. In this case that meant choosing to subtract Red and not add Green.

 

Rick

[yenlo]

My guess: Mz = M9; Mx = M (Typ 240)

u got me 2, adan ;-)

 

/chris

[jaapv]

NO! NO! NO!

 

Dweebs, the answer to your question of why you don't add green is that it is easier to subtarct red.

 

The reason it easier to subtract red is multifactorial. First, the photo I used (you probably have a copy of it on your computer) shows more red on the left side. This example shows too much red not too much green. So, it is first of all easier to identify the red tone (because it is obvious). All you have to do is use the tone color dropper and pick a red color off the table on the left. If, you wanted to add green... what tone of green are you going to pick and from where? You could do it, but why make it difficult.

 

Next, you always want to mix down. When using the Tone Curves it is almost always advantages for many reasons to subtract color... or mix down. You never hear the phrase mix-up? You always do the mix down. If, you were to start adding color (green) you are mixing up. Eventually, you run into the upper limit of the dynamic range and you lose the mix. Always mix down and pull the noise floor down. Once the color channels are balanced the way you want them you can globally mix up the whole photo with all channels if needed.

 

So, once I chose the red color tone I wanted using the dropper-like tool in curves... I pulled the curve down and got the best color balance I could using the Red Channel curve point the dropper selected off the red portion of the table.

 

Then, I went back up to the WB module and used Color and Tint to balance the Blue and Green globally.

 

Lastly, I am on my MacAir (poor color screen). So, I then used the black color swatch on the color card to tweak the balance of the RGB channels. With my curser over the black swatch, I adjusted the WB Color then the WB Tint to get the RGB values under the Histogram to be about equal.

 

Most always - Identify the ofending color and mix color tones

down

not up. In this case that meant choosing to subtract Red and not add Green.

 

Rick

I only agree half. It is basically a matter of balancing the opposing colours, as anybody who has ever tweaked an A curve can testify. You are certainly right that the effect of reducing red is different from adding green, and mostly preferable (which goes for all opposing colours), but that is mainly caused by the RGB colour space as the colour information is linked to the luminosity. As soon as you take the luminosity into its own channel aka LAB there is no difference any more

[Rick]

I only agree half. It is basically a matter of balancing the opposing colours, as anybody who has ever tweaked an A curve can testify. You are certainly right that the effect of reducing red is different from adding green, and mostly preferable (which goes for all opposing colours), but that is mainly caused by the RGB colour space as the colour information is linked to the luminosity. As soon as you take the luminosity into its own channel aka LAB there is no difference any more

 

All true. But, LAB is a lot of extra steps. We talked around this a year or two ago. I have used LAB very little over the last 2 years. I have found I can get what I want most of the time from LR with the exception of per pixel adjustment that need PS.

 

My example is for LR. It doesn't hold completely for LAB. I was trying to point out that you can access a curves-like module in LR rather than going into PS if, you don't have to. I only used 3 steps as you can see in the LR history. Elegant, no?

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Hallo,

Look here: Leica M

[jaapv]

All true. But, LAB is a lot of extra steps. We talked around this a year or two ago. I have used LAB very little over the last 2 years. I have found I can get what I want most of the time from LR with the exception of per pixel adjustment that need PS.

 

My example is for LR. It doesn't hold completely for LAB. I was trying to point out that you can access a curves-like module in LR rather than going into PS if, you don't have to. I only used 3 steps as you can see in the LR history. Elegant, no?

Sure. I only pointed it out to enhance my reputation as a pedantic bloke :