# Lens Correction Profile



## malcolmsu (Nov 30, 2016)

Can someone help explain what's happening here and what (if anything) I should be doing to correct what's happening?

I've been using a Sony RX100 compact camera of late instead of my usual DSLR. When I select a RAW picture in the Develop module (LR CC) and select Lens Corrections and then Profile, I get an error message "Unable to locate a matching profile automatically". 

So then I jump down to Lens Profile and select Sony from Make. That then populates the model and profile with lens details i don't recognise.  However at the same time there's an information message that says "bult-in lens profile applied". 

I can select my actual lens from the model list and it then correctly identifes my camera model too, but tne info message is still there.  

If i untick and tick the enable profile corrections box I do see some difference in the picture on screen.

What should i do? Not appliy the profile correction as it's already built in as the message suggests?  Or should I ignore the message and apply the profile?


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## Paul B (Nov 30, 2016)

One of my cameras is a Sony; an RX10. I get similar behaviour. Without selecting anything, I get the '_i_' icon and 'built-in lens profile applied'. If I click the icon it tells me "Sony DSC-RX10M3 24-600mm F2.4-4.0  This raw file contains a built-in lens profile for correcting distortion and chromatic aberration. The profile has already been applied automatically to this image."

So I assume that I don't have a choice in applying a profile; it's been applied automatically. Personally I'd leave the Enable Corrections box unchecked.


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## LouieSherwin (Dec 1, 2016)

There may be an option in the camera menus to disable in camera lens corrections. Have you tried turning that off? 

It appears that some or perhaps all of these corrections may be applied to raw as well as JPG files. I have not be able to definitively determine if this is true or not. But when looking at Lens Correction tab for the images that I recently took using my A7RII and the Sony 24-70 F4 lens, I see an little notice "Built in Lens Profile applied". When I click on the little info button "i" I get a popup explaining that "

Sony ILCE-7RM2
FE 24-70mm F4 ZA OSS

This raw file contains a built-in lens profile for chromatic aberration. The profile has already been applied automatically to this image.​
When examining the images it appears to be true even though I have explicitly disabled that in the camera menu. 

-louie


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## Johan Elzenga (Dec 1, 2016)

I believe the explanation is as follows: the built-in profile is not _applied_ to the raw data in the camera, but added to the metadata. You can't apply chromatic aberration correction to non-demosaiced data. Lightroom reads this profile and automatically applies it. That is why it says that the profile is applied, even if that option was disabled in the camera (for jpeg, that is).


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## LouieSherwin (Dec 2, 2016)

I started a discussion on the Adobe Lightroom forum to try to better understand this.

Sony built-in lens profile applied |Adobe Community

I agree with Paul that regardless if the profile corrections are available in the raw file the Lens Correction check boxes should control whether they are applied or not. 

-louie


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## Johan Elzenga (Dec 2, 2016)

In the threads you refer to, a good explanation is given why this would not be a good idea. These lenses are _designed_ with profile-based correction taken into account.


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## LouieSherwin (Dec 2, 2016)

It seems that Sony, Fuji, and M4/3 have collaborated with Adobe to unilaterally apply various lens corrections in spite of the in camera menu settings and Adobe develop settings. One explanation seems to be that this is "required" to allow cost effective lens designs. I'm having a hard time buying that for the top of the line ($1400 to $2500 per lens) lenses I am looking at.

As I said on the other discussion I am not expecting a perfect lens rather that I just want the option to see what I am paying for.

I guess it's off to the feedback site to register my concerns there. 

-louie


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## Victoria Bampton (Dec 4, 2016)

To be fair, I think it's the camera manufacturer's you need to complain to, because I understand they're the ones who have "required" that their lens corrections be applied without letting you turn them off. Adobe are just not arguing.


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## Johan Elzenga (Dec 4, 2016)

I'd agree, except for one situation: I use a Sony A7R with a Metabones adapter and Canon lenses. When I've used the Canon 24-70 f/4.0L IS USM lens on this camera, it adds the profile of the Sony FE 24-70mm F4 G SSM OSS lens and so Lightroom says this profile is applied for chromatic aberration. I apply the correct Canon lens profile in Lightroom, but that does not seem to overrule the built-in profile. I do not see any real problem in practise (the images look good with no visible distortion), but in this case I would have liked to be able to turn off that Sony profile, just to be sure. After all, it's simply the wrong profile.


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## Paul B (Dec 4, 2016)

Interestingly, one of the post's on Louie's Adobe thread points refers to another source which attempts to justify this behaviour. Quoting from that source (my bold):

"_*The built-in profiles are necessary for the non-removable lens cameras because they prioritize compact lens over a less distorted lens.* They intentionally allow the lens to have a high degree of distortion to get such a long zoom range in such a small lens. Therefore the camera applies a radical amount of built-in correction to make a camera generated JPEG image look normal. But the raw has no correction so it will look horribly distorted unless the first edit in the raw software is the same radical correction, which is provided by the built-in profile.

There is no such thing on DSLRs because you can't count on a camera knowing how to un-distort any random lens you attach to it, therefore the lens must have inherent low distortion, so lens design prioritizes low distortion over compact lens size._"​
Let's suppose that is true. So for bridge Sony's like the OP's and mine, enforced correction makes sense because of the degree of out-of-camera distortion. But for Louie and Johan using interchangeable lenses it does not seem to make so much sense.

_Edited to remove some bad reasoning on my part!_


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## Johan Elzenga (Dec 4, 2016)

Paul B said:


> _There is no such thing on DSLRs because you can't count on a camera knowing how to un-distort any random lens you attach to it, therefore the lens must have inherent low distortion, so lens design prioritizes low distortion over compact lens size._"



I think this statement is debatable anyway. If the lens contained a chip with the lens profile, there is no reason why a DSLR camera could not read that profile and correct its JPEG's for the distortion of such a lens. This may not happen in practise right now (it appears that the camera itself contains these profiles, otherwise my Sony A7R could never apply the Sony profile when I use a Canon lens), but the problem of 'random lenses' _could_ be addressed this way.


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## Paul B (Dec 4, 2016)

JohanElzenga said:


> I think this statement is debatable anyway. If the lens contained a chip with the lens profile, there is no reason why a DSLR camera could not read that profile and correct its JPEG's for the distortion of such a lens. ...  the problem of 'random lenses' _could_ be addressed this way.


True enough. Interesting that the Sigma Art lenses go a step further in treating the lens as a separately configurable piece of hardware; there does seem to be a shift towards making the lens less of a 'dumb unit'. Being able to fine tune my own lens was a revelation.


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## LouieSherwin (Dec 4, 2016)

Victoria Bampton said:


> To be fair, I think it's the camera manufacturer's you need to complain to, because I understand they're the ones who have "required" that their lens corrections be applied without letting you turn them off. Adobe are just not arguing.



I am not sure how the manufactures can "require" Adobe to do anything. Perhaps there is some confidential behind the scenes agreements.  I also don't recall any notice or announcement that builtin lens profiles would be automatically applied. It seems that this "feature" has been silently slipped in without any user input.


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## LouieSherwin (Dec 4, 2016)

Just to reiterate, on my AR72 at least, there are options in the camera menus to turn off all lens compensations. These seem to function as expected for in camera generated JPGs. However, it seems that for raw files sent to Lightroom and probably Camera Raw the CA corrections are always applied regardless of the in camera setting.

This test was done back in March of 2015: In-camera lens compensation


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## Victoria Bampton (Dec 5, 2016)

LouieSherwin said:


> I am not sure how the manufactures can "require" Adobe to do anything. Perhaps there is some confidential behind the scenes agreements.



Let's rephrase that to "it's politically a wise move to comply with the manufacturer's request" since Adobe relies on some level of cooperation from the manufacturers.

If lens profiles are automatically applied by Lightroom, there's an i in a circle further down the Lens Corrections panel, and clicking on it will say what's being done based on the information stored in the file.


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## LouieSherwin (Dec 6, 2016)

Victoria,

As usual you are more in the know that the rest of us. I received a response to my question from Chris Castleberry and here is what he had to say.



			
				Chris Castleberry said:
			
		

> Per request from Sony, Lightroom will enable the external lens profile automatically for raw files if the lens comp settings are enabled in the camera and an external profile is available in the version of the application you are running. The external profile corrects for geometric distortion and vignetting only. The chromatic aberration correction is baked into the raw file using opcodes that cannot be disabled in Lightroom.



I find the last sentence particularly intriguing. I speculate here but I suspect that Sony is may in fact be providing Adobe with the raw conversion code to use in Lightroom. Which could explain why these "opcodes" cannot be disabled by Adobe. 

So with respect to the automatic CA corrections I think that is a bug in the Sony firmware to unconditionally enable it in raw files but allow the user to turn it off for in-camera generated JPGs. 

Off to find an appropriate place to report this to Sony.

-louie


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## Victoria Bampton (Dec 8, 2016)

LouieSherwin said:


> I speculate here but I suspect that Sony is may in fact be providing Adobe with the raw conversion code to use in Lightroom.



For the lens corrections, yes. There's a bit of blurb about opcodes and what they can do here: DNG specification


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