In-camera lens compensation

16-35-10-18 deuHigh resolution sensor are really demanding when it comes to the resolution of the lens as well as to shading, chromatic aberration and distortion which are more important on DSLMs like the Sony A7 and the Sony A6000 due to the shorter flange (distance between sensor and lens mount). Most of these optical errors can already be corrected in the construction of the lens for a higher price (see Zeiss Otus). In-camera lens compensation is one mean to reduce the costs of lens construction. This article shows the effects of the three different correction parameters of the in-camera lens compensation on JPG and RAW based on pictures taken with the combinations of Sony Vario-Tessar® T* FE 16-35mm F4 ZA OSS on the Sony A7 and Sony E 10 – 18mm F4 OSS on the A6000.

Trade-Off

Many DSLR (Digital Single-Lens Reflex) and DSLM (Digital Single-Lens Mirrorless) user want more and more megapixel; be it the professional photographer who wants the best possible quality for large prints or be it the ambitious hobby photographer who simply wants the best gear for his hobby or the beginner who thinks that more resolution is equal to better pictures.

The trade-off between lens price and quality called „in-camera lens correction“ is fed by the ambitions of the manufacturer who wants to build the best product possible and the photographer who wants to use the best possible lens for the lowest price. The most uncomprising lenses currently available which deliver outstanding image quality on mainly all availble sensors are surely the Otus lenses build by Zeiss. Image quality which one can expect at a price level far above the level of $ 3.000. This lens are surely made for the enthusiasts which have the money and the willingness to pay the price and less interesting for the professionals that think in economic dimensions or the hobbyist with smaller budget. The later are rather interested in those lenses found at mid-range price levels which deliver the best performance in combination with the internal lens corrections – as far as available in the camera firmware.

A note to the image material

Cameras and lenses

Using a full-frame lens on a camera with APS-C sensor would not really show the real amount of distortion and shading because the APS-C sensor is only using the good center part of the full-frame lens. The following drawing shows the relationship of image circle and sensor size of full-frame and APC-C sensors:

Sensor_Bildkreis_eng

The in-camera lens correction is best shown when using wide-angle focal length and surely in the outer image areas and corners of the picture. The following combinations of camera and lens have been used to create as much lens errors as possible:

  • Sony A7 with Sony Vario-Tessar® T* FE 16-35 mm F4 ZA OSS
  • Sony A6000 with Sony E 10 – 18 mm F4 OSS

16-35-10-18RAW and JPG

There is an ongoing discussion whether the in-camera lens correction is applied to RAW images. All pictures have been made in RAW and JPG each with activated and deactivated lens correction to find out whether lens correction is applied to RAWs.

All comparable pictures have been taken with the same event of simultaneous shutter release in Sony A7 and Sony A6000 to create the highest rate of comparability and to avoid difference in images caused by e.g. cloud moving into sunlight. The cameras have been mounted as shown in below picture and the shutter was released by a radio trigger.
P1030986

Analysis of images

Shortly after Sony started selling the lens I wrote a first Hands-on about the Sony Vario-Tessar® T* FE 16-35mm F4 ZA OSS. In one of the comments of the German version of the hands-on I was asked about my opinion on the in-camera lens correction – here it is.

Frame 1 – Chromatic aberration

SEL 10-18mm F4 OSS, JPG and RAW, mit und ohne Korrektur / with and without correction

M1_CropBereichThe red marked area is used for comparison of JPGs and RAWs:

JPG_RAW_10-18F4_off_auto_crop
left: lens correction off | right: lens correction auto

Looking at the crops the JPGs shot with deactivated lens corrections there are green and purple lines next to the tree branches – as expected. Surprisingly, these chromatic aberrations are not visible in the RAWs even with deactivated lens correction. Hardly believable, but I checked all RAWs one by one and this looks like the proof that the correction of CAs can’t be disabled for RAWs. As a comparison below the the crops from the images shot with the FE 16-35 mm F4 ZA OSS at 16 mm and at F5.6, because I made a focussing mistake taking the pictures at F4 which I realised to late, but this does not influence the assessment of chromatic aberrations.

JPG_RAW_16-35F5,6_off_auto_crop
left: lens correction off | right: lens correction auto

Obviously the FE 16-35mm F4 ZA OSS mounted on alpha 7 shows the same results like the SEL 10-18mm F4 OSS mounted on alpha 6000 regarding the correction of chromatic aberrations on RAWs.

Frame 2 and 3 – Shading and distortion

The following pictures show the effect of in-camera lens correction regarding corner shading and distortion. Please move the mouse pointer over the image to toggle the view between activated and deactivated correction:

SEL 10-18mm F4 OSS @ F4 – JPG:

ausgeblendeter Text: mouseover JPG 10-18mm F4

SEL 10-18mm F4 OSS @ F4 – RAW:

ausgeblendeter Text: mouseover RAW 10-18mm F4

It is easily visible that the correction of shading is applied to the RAWs as well, whereas the activation or deactivation of the correction of distortion has no effect on the RAWs. The following comparison between JPG and RAW with deactivated correction of distortion shows, that JPG and RAW are the same. The small differences in shading are caused by the selected creative style „Neutral“ and are not related to any lens correction.

ausgeblendeter Text: mouseover RAW+JPG Aus 10-18mm F4

Let’s have a look on the same images shot with FE 16-35mm F4 ZA OSS mounted on the alpha 7. Again, please mouse over to toggle view::

FE 16-35mm F4 ZA OSS @ F4 – JPG:

ausgeblendeter Text: mouseover JPG 16-35mm F4

FE 16-35mm F4 ZA OSS @ F4 – RAW:

ausgeblendeter Text: mouseover RAW 16-35mm F4

FE 16-35mm F4 ZA OSS @ F4 – JPG+RAW deactivated correction:

ausgeblendeter Text: mouseover RAW+JPG Aus 16-35mm F4

There is a lot more image material taken from other subjects and with different apertures and focal lengths and lens correction activated or deactivated which I did not include in this article but which I provide as zip-files for download at the end of this post and which can be used for your own analysis. If you use this material for your own publications I only require being listed as reference with a link to this post.

Verdict

Pictures are worth more than a thousand words and following this motto the diagramm below provides an overview on which correction parameter is applied to JPG and RAW when the lens correction is activated or deactivated (black means that this particular corrections shows in the pictures).

Matrix_ObjektivkorrekturTwo results are quiet suprising: First is that the correction of chromatic aberrations can be deactivated for RAWs when there is a lens corrections profile for the used lens contained in the installed firmware and second, that that there is no correction of distortion in RAWs, no matter whether this parameter is activated. Lens-correction profiles can only be added to the camera with a new firmware.

The alternative is to use the Sony PlayMemories Camera App „Lens Compensation“ to create your own profile for lenses not yet supported or that will never be supported (legacy lenses) by the firmware and automatically apply the lens correction – but this is a different and very interesting subject.

Now it is up to you to find the conclusion on which lens delivers satisfying results on which camera and taking the price into consideration by using the provided download links to the RAWs and JPGs.

Download link RAWs

Download link JPGs

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9 Antworten zu In-camera lens compensation

  1. marc champollion sagt:

    Ich lese in ernstzunehmenden Testberichten immer wieder, wie stark die Schärfe (Definition in L/mm oder L/Bildhöhe) in den Ecken nachlässt, ohne, dass mit einem Wort erwähnt wird, ob mit oder ohne Korrektur gemessen worden ist. Jetzt aber beginne ich, zu ahnen, dass es gar nicht so einfach ist, zu wissen, ob diese kamerainterne Korrektur eingreift oder nicht. Es müsste also zuerst eruiert werden, wann diese Korrektur (bei Fuji z.B. heisst sie LMO) eingreift, und das kann recht zeitraubend sein. Bei starken Weitwinkelobjektiven, vor allem bei den billigeren, am schlimmsten bei WW-Zooms, ist u.a. schon die Verzeichnung so stark, dass sie wahrscheinlich immer intern korrigiert wird. Ausnahme: man benutzt z.B. ein Olympus Objektiv, wie das 9-18mm, an einer Panasonic, wie ich es mache, weil Panasonic kein so putziges UWW anzubieten hat (153 Gramm!). Ich habe dann über die stark gekrümmten Linien nicht schlecht gestaunt. Aber man kann diese Verzeichnung mit geeigneten Programmen am Rechner im Nachhinein korrigieren, genau, wie man stürzende Linien wieder „richtem“ kann. Nur muss die Elektronik in jedem Fall interpolieren, und das senkt die Schärfe beachtlich. Man kann Architekten und Bildbandfotografen also nur empfehlen, Objektive zu verwenden, die keiner Korrektur bedürfen, was natürlich schwer ins Geld geht, weil diese Objektive auf Grund der verschwindend kleinen Serien immens teuer geworden sind. Oder man greift auf frühere Objektive aus der guten alten, analogen Zeit zurück, wie z.B. das sehr gute Leica Elmarit-R 2,8/19mm, oder sogar auf die guten, letzten M-Objektive wie die letzten Versionen der 21mm, vorausgesetzt, sie lassen sich auf moderne Digitalkameras verwenden, was bei den Spiegellosen kein Problem sein sollte wegen der kurzen Schnittweite; sowohl die Fuji X- wie die Sony Alpha 24×36 haben sehr kurze Auflagemaße, die sogar deutlich kleiner sind, als dasjenige der M-Leica (27,8mm). Die Frage ist nur, ob die wenig telezentrische Konstruktion eines 21mm für die Leica M mit dem Sensor Probleme verursacht. Dann blieben nur noch die besten Retrofokus-Konstruktionen wie das schon erwähnte Leica-R 19mm, Zeiss Distagone und einige anderen von z.B. Nikon und Canon.
    Marc Champollion

  2. James Backer sagt:

    Not sure what software you are using where you cannot turn off the auto leans corrections? I have an A7r with FE 16-35 and have always had the ability to simply toggle On / Off any of the 3 lens correction options in Adobe lightroom or Adobe Camera Raw (ACR). This feature has worked since my Preordered FE 16-35 was delivered regardless of the new Sony lens firmware updates that became available recently. One thing to note is in Lightroom I import all my ARW files with auto lens corrections enabled and with Camera Calibration set to „Camera Standard“. To view the ARW image with lens correction for distortion „Off“ you must make sure that in the ‚Lens Correction‘ module that in both the ‚Basic‘ tab and the ‚Profile‘ tab that the „enable lens corrections“ checkbox is deselected. After the recent lens firmware updates from Sony I noticed a significant improvement in distortion correction at 16mm – 20mm

    In addition I have created a few ‚custom‘ vignette profiles for the FE 16-35 which improve the corners when shooting at 16mm – 20mm. I find setting the ‚Profile‘ tab ‚Vignette slider‘ to about 160 gives almost perfect corner exposure when shooting deep blue skies at 16-20mm. Note: Make sure that the ‚vignette‘ slider under the ‚Lens correction‘ Manual tab is set to ‚0‘ or it will apply both settings combined and seems to introduce more noise.

    • J. Haag sagt:
      Verfasser

      James, thanks for you comment. I am using Lightroom 5 with default settings which probably do more than 80 % of Lightroom users. I always import my pics with no profiles or templates applied to them, just to be sure to have as much control as possible.

      • James Backer sagt:

        I think you missed the main point of my comment above…. Distortion Correction IS built into all Sony ARW files as long as you activated the parameter for the lens ‚in camera‘. It CAN be turned ON or OFF for both ARW and JPEG files in both Lightroom and ACR and other compatible software. Your diagram and comment above is incorrect:

        „…that there is no correction of distortion in RAWs, no matter whether this parameter is activated. Lens-correction profiles can only be added to the camera with a new firmware.“

        Also the Sony Distortion correction profiles are built into Adobe Lightroom and ACR for all Sony native E-mount lenses. These corrections can be applied to ARW files easily in the Lightroom ‚lens correction‘ module. I think you may have somehow lost the connection in Lightroom that automatically links the Sony specific lens distortion correction profiles to the ‚Lens Correction‘ module.

        A simple way to verify that the distortion correction profiles are included with your ARW files is to simply open any ARW file in ‚Sony’s Image data converter 4‘ or „Capture One for Sony“ software and toggle the distortion correction on and off.

      • J. Haag sagt:
        Verfasser

        Yes, I missed your point and you are absolutely right.
        Thanks, Jörg

    • I think you’re mixing 2 different things. I believe Jörg’s diagram is correct.
      – LR takes its lens distortion correction from its database of lens-profile files. That’s what you’re applying in the „Lens Correction“ module.
      – However, Sony also embeds its own lens correction information in the ARW-file (SR2SubIFD tag 0x7982, mirrored in Exif SubIFD tag 0x7037 – it’s written independently of your off/auto setting for distortion correction), which LR then chooses to completely ignore. Interestingly, when you run the ARW through Adobe’s DNG-converter, it writes the information into an XMP-tag („LensDistortInfo“). Meaning, it does read the information but doesn’t use it.

      For CA, it’s the opposite. The equivalent tag in the ARW is always interpreted by LR, no matter your camera setting.

      I documented my findings on this a while ago at https://variousphotography.wordpress.com/ if anybody is interested in digging deeper.

  3. Pat Lopez sagt:

    This was a well written and thoughtful post. I greatly enjoyed it. Your point regarding the alternatives for image correction and their corresponding costs (in camera software correction vs. more expensive, and I would add heavier, lenses) is well made. I would also suggest third party software and post processing as another alternative that comes with it own costs (money and time). You frame the issue in a way that gives us all something to think about the next time we chose a new camera or lens. Thank you,
    Pat

    • J. Haag sagt:
      Verfasser

      Pat, thanks for your comment. Actually, I can’t tell what happens to pictures from Canon / Nikon or any other manufacturer when loaded into Lightroom. I think, that Sony is causing more issues and confusion than doing any good with either applying lens profile changes to the RAW or with „allowing“ Lightroom to apply these changes during import (if that is the case).

  4. Thomas sagt:

    Hi Jorg – very interesting test.

    I noticed this some time ago in Lightroom (4 and 5). I noticed that with the Sony NEX6 or A6000, the lens profile option „Chromatic Aberration“ had no effect at all on the images, and there was no sign at all of chromatic aberration in any image (which seemed impossible). Meanwhile, the „Distortion Correction“ option did have an effect on the images, straightening barrel or pincushion distortions. I was forced to conclude that either Sony lenses were exceedingly good (hahaha), or that chromatic aberration correction was being baked in to the RAW images.

    This was exceedingly obvious to me, because at the time I was also using a Canon 7D and several L series lenses in excellent optical condition, and ALL images from the Canon system benefited significantly from chromatic aberration correction in Lightroom.

    Clearly it was impossible that the cheap Sony 16-50 kit lens (which exhibited insane amounts of everything bad on my FS700 cinema camera prior to the lens correction firmware update for that unit) had absolutely no chromatic aberration while an expensive Canon L series had noticable amounts.

    Thank you for scientifically testing this, it is something that Sony do NOT clearly state in their documentation. It’s also a shame that the correction tables are not held in the LENS firmwware so that all future lenses were automatically compatible with existing Sony cameras. Sony do not have a great history for updating firmware on their cameras, and with the E-mount system still so young, it’s a sure bet that there will be many future lenses incompatable with cameras of today.

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