My Lightroom lens corrections need correcting. Is this normal?

Question

I have bought myself my 1st DSLR camera (Nikon D3100) as i now want to shoot Raw instead of Jpeg. I've always shot Jpegs in the past with my old cameras. The in-camera Jpegs from my new Nikon don't show any lens distortion. However, when i open the Raw (NEF) files in Lightroom and tick 'enable profile correction' in the Lens corrections section, the distortion correction seems too much and i have to manually adjust it every time.
The lens profile comes from Lightroom itself (not from other users), & so this doesn't seem quite right to me that the correction is somewhat wrong each time.
I'm wondering if i'm doing something wrong or that maybe its even normal to have to adjust the correction further yourself each time (and perhaps most users have to do that too)?
I've included 3 Jpegs of the same image to demonstrate the problem (detailed below):
1) The export from Lightroom with the lens distortion corrected by Lightroom (note the straight red line).
2) An exported Jpeg version of the uncorrected Nef from Lightroom  (to show the full original lens distortion)
3) The original in-camera Jpeg (obviously the distortion corrected by the camera)
I've  drawn straight red lines on to the images to demonstrate the differences.
Any ideas?
^ above image is a Lightroom exported Jpeg (from NEF) with lens correction ON (note the red line along the top of the roof)
^ above image is a Lightroom exported Jpeg (from NEF) with NO lens correction yet, thus showing original distortion.
^ above image is the ORIGINAL in-camera JPEG showing no distortion at all (note the red line along the top of the roof).
P.s i've taken different shots too and the problem is the same for them all (at least at 18mm anyway).
Additional information:
The Nikon D3100 has an APS-C sensor (I'm not sure if that's significant or not). Also the lens described in the profile correction matches the one from my camera.

Answer 1

Rob Cole wrote:
Hi Paul,
I'm really not sure exactly what DxO outputs when you choose DNG:
It's not raw data, yet preserves some ability to do raw things in Lightroom, like white balance and camera profiles.
I dunno about pulling from highlight/shadow "reserves", but note: it's different than a DNG-wrapped tif or jpeg, it may be able to pull from the highlight/shadow reserves as can be done via the DNG used for smart previews - I just don't know.
trshaner: do you know for sure that a DxO DNG hard-clips shadows/highlights, or are you just "extrapolating/assuming/educatedly-guessing"?
Regardless, DxO has some auto shadow/highlight recovery (for those extreme black/white tones) that is quite good - don't sell it short.
Google 'dxo linear dng highlights.' Here's one that supports what I said:
http://forums.adobe.com/thread/663428
I've tried using Canon's DPP for the same purpose with TIFF output AND with DPP's highlight recovery. I can't get the same highlight recovery with the TIFF as compared to the raw inside LR with PV2012.
Rob Cole wrote:
I still think about it when Lr's lens corrections are wonky. But my problem with Lr's lens corrections have more to do with vignetting than distortion (because I mostly shoot nature, not buildings...), and I can add manual correction and/or a dab of paint to the automatic corrections, which saves me the complication of front-ending via DxO. If distortion is your primary concern, consider balancing auto with manual distortion corrections (I've not done much of that, so no guarantee...). Also, there's the upright feature in Lr5...
What's wrong with simply changing the Lens Profile 'Amount' settings from 100 if a specific lens profiles is "over-correcting" or "under-correcting? Don't forget most zoom lenses have a "complex" moustache shaped distortion, which is NOT easily corrected with LR's Manual Distortion control. You can certainly try both, but there's no way to save the Manual Distortion "correction" setting to a specific lens profile's defaults.
Rob Cole wrote:
PPS - DxO's purple fringe tool will get the fringe out without the artifacts of Lr's global defringer, however it may also take away real image color sometimes, and can't be done locally, so one may ultimately get better results in Lr if willing to spend a while painting local defringing.
I've never seen any artifacts caused by the LR Defringe tools (see image posted of Canon 8-15mm Fisheye lens CA), but you do need to be very careful concerning the actually settings used. After using the eyedropper tool to sample a fringe area I fine tune the settings to eliminate desaturation of areas that have similar color as the fringe area. Once you have the correct settings save it to a Develop preset for manual application. For example with my Canon 8-15mm F4L Fisheye zoom I have two (2) Develop presets of 8-12mm (Purple 2, 30/55) and 13-15mm (Purple 4, 30/55). There is no need to use Local controls with Defringe if you follow my suggestions for manually tuning the settings to prevent desaturation in like colored areas. IMHO the LR CA and Defringe tools are darn near perfect when you use them correctly!