What is in a raw file? It sure isn't a picture

[The_Traveler]

Here is a picture taken way back in 2006.
I removed some perspective distortion, added a bit of contrast, did a tiny bit of sharpening and cropped it.
The Nef file (the Nikon Raw file) is unchanged but Lightroom added a sidecar file with the same name but the suffix of .xmp that is simply the Metadata Plus an extensive description of how the file was edited.

When the NEF is opened again, these edits are applied before you see it.
These edits can be easily reversed in LR or other editors.

<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 5.5-c002 1.148022, 2012/07/15-18:06:45 ">
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdfescription rdf:about=""
xmlns:tiff="http://ns.adobe.com/tiff/1.0/"
xmlns:exif="http://ns.adobe.com/exif/1.0/"
xmlns:xmp="File management, metadata integration | Adobe Extensible Metadata Platform (XMP)"
xmlns:aux="http://ns.adobe.com/exif/1.0/aux/"
xmlns:Iptc4xmpCore="IPTC document"
xmlnshotoshop="Photo editor | Download free Adobe Photoshop CC trial"
xmlns:crs="http://ns.adobe.com/camera-raw-settings/1.0/"
xmlns:xmpRights="File management, metadata integration | Adobe Extensible Metadata Platform (XMP)"
xmlns:dc="DCMI Metadata Terms"
xmlns:crss="http://ns.adobe.com/camera-raw-saved-settings/1.0/"
xmlns:lr="http://ns.adobe.com/lightroom/1.0/"
xmlns:xmpMM="File management, metadata integration | Adobe Extensible Metadata Platform (XMP)"
xmlns:stEvt="File management, metadata integration | Adobe Extensible Metadata Platform (XMP)"
tiff:Make="NIKON CORPORATION"
tiff:Model="NIKON D70"
tiff:Orientation="1"
tiff:ImageWidth="3008"
tiff:ImageLength="2000"
exif:ExifVersion="0221"
exif:ExposureTime="1/50"
exif:ShutterSpeedValue="5643856/1000000"
exif:FNumber="11/1"
exif:ApertureValue="6918863/1000000"
exif:ExposureProgram="3"
exifateTimeOriginal="2006-01-17T10:47:54.70-05:00"
exif:ExposureBiasValue="0/6"
exif:MaxApertureValue="38/10"
exif:MeteringMode="5"
exif:LightSource="0"
exif:FocalLength="250/10"
exif:SensingMethod="2"
exif:FileSource="3"
exif:SceneType="1"
exif:FocalLengthIn35mmFilm="37"
exif:CustomRendered="0"
exif:ExposureMode="0"
exif:WhiteBalance="0"
exif:SceneCaptureType="0"
exif:GainControl="0"
exif:Contrast="0"
exif:Saturation="0"
exif:Sharpness="0"
exif:SubjectDistanceRange="0"
exifigitalZoomRatio="1/1"
exifixelXDimension="3008"
exifixelYDimension="2000"
xmp:ModifyDate="2006-01-17T10:47:54.70-05:00"
xmp:CreatorTool="Ver.1.03"
xmp:CreateDate="2006-01-17T10:47:54.70-05:00"
xmp:Rating="1"
xmp:MetadataDate="2015-01-22T10:09:36-05:00"
aux:LensInfo="180/10 700/10 35/10 45/10"
aux:Lens="18.0-70.0 mm f/3.5-4.5"
aux:ImageNumber="5927"
Iptc4xmpCore:CountryCode=""
photoshop:Country=""
photoshop:Category=""
photoshopateCreated=""
photoshop:State=""
photoshop:CaptionWriter=""
photoshop:Headline=""
photoshop:SidecarForExtension="NEF"
photoshop:EmbeddedXMPDigest="00000000000000000000000000000000"
crs:Version="8.7"
crsrocessVersion="5.0"
crs:WhiteBalance="As Shot"
crs:AutoWhiteVersion="134348800"
crs:Temperature="5550"
crs:Tint="-3"
crs:Exposure="+0.62"
crs:Shadows="5"
crs:Brightness="+50"
crs:Contrast="+25"
crs:Saturation="0"
crs:Sharpness="25"
crs:LuminanceSmoothing="0"
crs:ColorNoiseReduction="25"
crs:VignetteAmount="0"
crs:ShadowTint="0"
crs:RedHue="0"
crs:RedSaturation="0"
crs:GreenHue="0"
crs:GreenSaturation="0"
crs:BlueHue="0"
crs:BlueSaturation="0"
crs:FillLight="0"
crs:Vibrance="0"
crs:HighlightRecovery="0"
crs:Clarity="+37"
crs:HueAdjustmentRed="0"
crs:HueAdjustmentOrange="0"
crs:HueAdjustmentYellow="0"
crs:HueAdjustmentGreen="0"
crs:HueAdjustmentAqua="0"
crs:HueAdjustmentBlue="0"
crs:HueAdjustmentPurple="0"
crs:HueAdjustmentMagenta="0"
crs:SaturationAdjustmentRed="0"
crs:SaturationAdjustmentOrange="0"
crs:SaturationAdjustmentYellow="0"
crs:SaturationAdjustmentGreen="0"
crs:SaturationAdjustmentAqua="0"
crs:SaturationAdjustmentBlue="0"
crs:SaturationAdjustmentPurple="0"
crs:SaturationAdjustmentMagenta="0"
crs:LuminanceAdjustmentRed="0"
crs:LuminanceAdjustmentOrange="0"
crs:LuminanceAdjustmentYellow="0"
crs:LuminanceAdjustmentGreen="0"
crs:LuminanceAdjustmentAqua="0"
crs:LuminanceAdjustmentBlue="0"
crs:LuminanceAdjustmentPurple="0"
crs:LuminanceAdjustmentMagenta="0"
crs:SplitToningShadowHue="0"
crs:SplitToningShadowSaturation="0"
crs:SplitToningHighlightHue="0"
crs:SplitToningHighlightSaturation="0"
crs:SplitToningBalance="0"
crsarametricShadows="0"
crsarametricDarks="0"
crsarametricLights="0"
crsarametricHighlights="0"
crsarametricShadowSplit="25"
crsarametricMidtoneSplit="50"
crsarametricHighlightSplit="75"
crs:SharpenRadius="+1.0"
crs:SharpenDetail="25"
crs:SharpenEdgeMasking="34"
crsostCropVignetteAmount="0"
crs:GrainAmount="0"
crs:LensProfileEnable="1"
crs:LensManualDistortionAmount="0"
crserspectiveVertical="+21"
crserspectiveHorizontal="0"
crserspectiveRotate="0.0"
crserspectiveScale="100"
crserspectiveAspect="0"
crserspectiveUpright="0"
crs:AutoLateralCA="1"
crsefringePurpleAmount="0"
crsefringePurpleHueLo="30"
crsefringePurpleHueHi="70"
crsefringeGreenAmount="0"
crsefringeGreenHueLo="40"
crsefringeGreenHueHi="60"
crs:ConvertToGrayscale="False"
crs:ToneCurveName="Medium Contrast"
crs:ToneCurveName2012="Linear"
crs:CameraProfile="Adobe Standard"
crs:CameraProfileDigest="1D2B18E7ADE8EB1F68BC79DAFA30AAF5"
crs:LensProfileSetup="LensDefaults"
crs:LensProfileName="Adobe (Nikon AF-S DX Zoom-Nikkor 18-70mm f/3.5-4.5G IF-ED)"
crs:LensProfileFilename="NIKON D300S (Nikon AF-S DX Zoom-Nikkor 18-70mm f3.5-4.5G IF-ED) - RAW.lcp"
crs:LensProfileDigest="E89291B8905E38EEC9A1EE9C0D691D7E"
crs:LensProfileDistortionScale="100"
crs:LensProfileChromaticAberrationScale="100"
crs:LensProfileVignettingScale="100"
crs:HasSettings="True"
crs:CropTop="0.045989"
crs:CropLeft="0.030579"
crs:CropBottom="0.997573"
crs:CropRight="0.958"
crs:CropAngle="0.682806"
crs:CropConstrainToWarp="0"
crs:HasCrop="True"
crs:AlreadyApplied="False"
crs:RawFileName="2006 01 17Greenbelt_00129.NEF"
dc:format="image/x-nikon-nef"
xmpMM:InstanceID="xmp.iid:be24e52a-c756-6441-bf23-f355ff42e816"
xmpMMocumentID="xmp.did:be24e52a-c756-6441-bf23-f355ff42e816"
xmpMM:OriginalDocumentID="xmp.did:be24e52a-c756-6441-bf23-f355ff42e816">
<exif:ISOSpeedRatings>
<rdf:Seq>
<rdf:li>200</rdf:li>
</rdf:Seq>
</exif:ISOSpeedRatings>
<exif:Flash
exif:Fired="False"
exif:Return="0"
exif:Mode="0"
exif:Function="False"
exif:RedEyeMode="False"/>
<Iptc4xmpCore:CreatorContactInfo
Iptc4xmpCore:CiAdrPcode="21046-1318"
Iptc4xmpCore:CiAdrCtry="USA"
Iptc4xmpCore:CiEmailWork="art_photo@comcast.net"
Iptc4xmpCore:CiTelWork="301-576-4200"
Iptc4xmpCore:CiAdrRegion="MD"
Iptc4xmpCore:CiAdrExtadr="10096 Hatbrim Terrace"
Iptc4xmpCore:CiAdrCity="Columbia"/>
<crs:ToneCurve>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>32, 22</rdf:li>
<rdf:li>64, 56</rdf:li>
<rdf:li>128, 128</rdf:li>
<rdf:li>192, 196</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurve>
<crs:ToneCurveRed>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveRed>
<crs:ToneCurveGreen>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveGreen>
<crs:ToneCurveBlue>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveBlue>
<crs:ToneCurvePV2012>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012>
<crs:ToneCurvePV2012Red>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Red>
<crs:ToneCurvePV2012Green>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Green>
<crs:ToneCurvePV2012Blue>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Blue>
<xmpRights:UsageTerms>
<rdf:Alt>
<rdf:li xml:lang="x-default">typical fair use</rdf:li>
</rdf:Alt>
</xmpRights:UsageTerms>
<dc:creator>
<rdf:Seq>
<rdf:li>Lewis Lorton</rdf:li>
</rdf:Seq>
</dc:creator>
<dc:rights>
<rdf:Alt>
<rdf:li xml:lang="x-default">Lewis Lorton</rdf:li>
</rdf:Alt>
</dc:rights>
<dc:subject>
<rdf:Bag>
<rdf:li>1dd- things</rdf:li>
<rdf:li>1ff-TypeofPicture</rdf:li>
<rdf:li>Structure</rdf:li>
<rdf:li>graffiti</rdf:li>
<rdf:li>graphic</rdf:li>
<rdf:li>machinery</rdf:li>
<rdf:li>mineral</rdf:li>
<rdf:li>wall</rdf:li>
</rdf:Bag>
</dc:subject>
<crss:SavedSettings>
<rdf:Bag>
<rdf:li>
<rdfescription
crss:Name="Import"
crss:Type="Snapshot">
<crssarameters>
<rdfescription
crs:Version="8.7"
crsrocessVersion="5.0"
crs:WhiteBalance="As Shot"
crs:AutoWhiteVersion="134348800"
crs:AutoExposure="False"
crs:Exposure="0.00"
crs:AutoShadows="False"
crs:Shadows="5"
crs:AutoBrightness="False"
crs:Brightness="+50"
crs:AutoContrast="False"
crs:Contrast="+25"
crs:Saturation="0"
crs:Sharpness="25"
crs:LuminanceSmoothing="0"
crs:ColorNoiseReduction="25"
crs:ChromaticAberrationR="0"
crs:ChromaticAberrationB="0"
crs:VignetteAmount="0"
crs:VignetteMidpoint="50"
crs:ShadowTint="0"
crs:RedHue="0"
crs:RedSaturation="0"
crs:GreenHue="0"
crs:GreenSaturation="0"
crs:BlueHue="0"
crs:BlueSaturation="0"
crs:FillLight="0"
crs:Vibrance="0"
crs:HighlightRecovery="0"
crs:Clarity="0"
crsefringe="0"
crs:GrayMixerRed="0"
crs:GrayMixerOrange="0"
crs:GrayMixerYellow="0"
crs:GrayMixerGreen="0"
crs:GrayMixerAqua="0"
crs:GrayMixerBlue="0"
crs:GrayMixerPurple="0"
crs:GrayMixerMagenta="0"
crs:HueAdjustmentRed="0"
crs:HueAdjustmentOrange="0"
crs:HueAdjustmentYellow="0"
crs:HueAdjustmentGreen="0"
crs:HueAdjustmentAqua="0"
crs:HueAdjustmentBlue="0"
crs:HueAdjustmentPurple="0"
crs:HueAdjustmentMagenta="0"
crs:SaturationAdjustmentRed="0"
crs:SaturationAdjustmentOrange="0"
crs:SaturationAdjustmentYellow="0"
crs:SaturationAdjustmentGreen="0"
crs:SaturationAdjustmentAqua="0"
crs:SaturationAdjustmentBlue="0"
crs:SaturationAdjustmentPurple="0"
crs:SaturationAdjustmentMagenta="0"
crs:LuminanceAdjustmentRed="0"
crs:LuminanceAdjustmentOrange="0"
crs:LuminanceAdjustmentYellow="0"
crs:LuminanceAdjustmentGreen="0"
crs:LuminanceAdjustmentAqua="0"
crs:LuminanceAdjustmentBlue="0"
crs:LuminanceAdjustmentPurple="0"
crs:LuminanceAdjustmentMagenta="0"
crs:SplitToningShadowHue="0"
crs:SplitToningShadowSaturation="0"
crs:SplitToningHighlightHue="0"
crs:SplitToningHighlightSaturation="0"
crs:SplitToningBalance="0"
crsarametricShadows="0"
crsarametricDarks="0"
crsarametricLights="0"
crsarametricHighlights="0"
crsarametricShadowSplit="25"
crsarametricMidtoneSplit="50"
crsarametricHighlightSplit="75"
crs:SharpenRadius="+1.0"
crs:SharpenDetail="25"
crs:SharpenEdgeMasking="0"
crsostCropVignetteAmount="0"
crsostCropVignetteMidpoint="50"
crsostCropVignetteFeather="50"
crsostCropVignetteRoundness="0"
crsostCropVignetteStyle="1"
crsostCropVignetteHighlightContrast="0"
crs:GrainAmount="0"
crs:GrainSize="50"
crs:GrainFrequency="50"
crs:LuminanceNoiseReductionDetail="50"
crs:ColorNoiseReductionDetail="50"
crs:LuminanceNoiseReductionContrast="50"
crs:ColorNoiseReductionSmoothness="50"
crs:LensProfileEnable="0"
crs:LensManualDistortionAmount="0"
crserspectiveVertical="0"
crserspectiveHorizontal="0"
crserspectiveRotate="0.0"
crserspectiveScale="100"
crserspectiveAspect="0"
crserspectiveUpright="0"
crs:AutoLateralCA="0"
crs:Exposure2012="0.00"
crs:Contrast2012="0"
crs:Highlights2012="0"
crs:Shadows2012="0"
crs:Whites2012="0"
crs:Blacks2012="0"
crs:Clarity2012="0"
crsefringePurpleAmount="0"
crsefringePurpleHueLo="30"
crsefringePurpleHueHi="70"
crsefringeGreenAmount="0"
crsefringeGreenHueLo="40"
crsefringeGreenHueHi="60"
crs:ConvertToGrayscale="False"
crs:AutoGrayscaleMix="False"
crs:AutoTone="False"
crs:EnableToneCurve="True"
crs:EnableSplitToning="True"
crs:EnableGrayscaleMix="True"
crs:EnableColorAdjustments="True"
crs:EnableDetail="True"
crs:EnableLensCorrections="True"
crs:EnableEffects="True"
crs:EnableCalibration="True"
crs:EnableRetouch="True"
crs:EnableRedEye="True"
crs:EnablePaintBasedCorrections="True"
crs:EnableGradientBasedCorrections="True"
crs:EnableCircularGradientBasedCorrections="True"
crs:ToneCurveName="Medium Contrast"
crs:ToneCurveName2012="Linear"
crs:CameraProfile="Adobe Standard"
crs:CameraProfileDigest="1D2B18E7ADE8EB1F68BC79DAFA30AAF5"
crs:LensProfileSetup="LensDefaults">
<crs:ToneCurve>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>32, 22</rdf:li>
<rdf:li>64, 56</rdf:li>
<rdf:li>128, 128</rdf:li>
<rdf:li>192, 196</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurve>
<crs:ToneCurveRed>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveRed>
<crs:ToneCurveGreen>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveGreen>
<crs:ToneCurveBlue>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurveBlue>
<crs:ToneCurvePV2012>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012>
<crs:ToneCurvePV2012Red>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Red>
<crs:ToneCurvePV2012Green>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Green>
<crs:ToneCurvePV2012Blue>
<rdf:Seq>
<rdf:li>0, 0</rdf:li>
<rdf:li>255, 255</rdf:li>
</rdf:Seq>
</crs:ToneCurvePV2012Blue>
</rdfescription>
</crssarameters>
</rdfescription>
</rdf:li>
</rdf:Bag>
</crss:SavedSettings>
<lr:hierarchicalSubject>
<rdf:Bag>
<rdf:li>1dd- things|Structure|wall</rdf:li>
<rdf:li>1dd- things|graffiti</rdf:li>
<rdf:li>1dd- things|mineral|machinery</rdf:li>
<rdf:li>1ff-TypeofPicture|graphic</rdf:li>
</rdf:Bag>
</lr:hierarchicalSubject>
<xmpMM:History>
<rdf:Seq>
<rdf:li
stEvt:action="saved"
stEvt:instanceID="xmp.iid:be24e52a-c756-6441-bf23-f355ff42e816"
stEvt:when="2015-01-22T10:09:36-05:00"
stEvt:softwareAgent="Adobe Photoshop Lightroom 5.7 (Windows)"
stEvt:changed="/metadata"/>
</rdf:Seq>
</xmpMM:History>
</rdfescription>
</rdf:RDF>
</x:xmpmeta>

 

[waday]

Neat!

I never realized there were so many smilies...

 

[photoguy99]

So, what IS a picture?

 

[JustJazzie]

This makes me wonder if anyone has ever tried to "write" a raw file from scratch and then plug it in as a photo. Hmmm.....could be a new art form? Lol

 

[Designer]

This makes me wonder if anyone has ever tried to "write" a raw file from scratch and then plug it in as a photo. Hmmm.....could be a new art form? Lol

They already do. Those goofy emotions are evidence that the programmer is smoking his socks while writing the code. He is simply playing with your mind as he creates the image. Sometimes called a "photograph". LOL

 

[The_Traveler]

This below are a few lines at 476111 in a raw file that is 47781 lines long (and that is a small D70 raw file)


‹åë€AŸ›Ÿ 1’=[è$ùuóÿÌÈÏÑ%›–êl¢XZ®Ó‹“Èív|\ÇŽBó¸AÙæµ´.Šã>ã€ÂmªîÿC¹“æ*G¶
‚A§ñs9J'Èjf:VO ç‹H{‹|ƒkÛŒÙY%24º–ÞAéÒn²‘%î_5N0NÕë,ô5#ŏgxì>PߢܙLƒÙî›öî,°ÃҍÛ1Xw‘Î^Üt‹Žæ_ üÁ¡:eŸ_ýë/‰"‘-Ýü'&É1x$yÍïéÙ¯ÌyxóÛ'qJoÚ<€ŠtƒÁã¹Î‘;½S,Íò_yýxgs–†¡ˆäñ(Ñíx~qÂ_#3¼ŽPxØÌê&ùŠA€€Áådžà ´â#⵩!"”‰@Ç~šûa™üµŒGd:”Åé¼’fÚd ‚gj÷9¬çSqЬÑ5]j{™æò¿ë=GÏ7JÛÆò¼M©Lûé¹:ƒˆG ŒÈ勶ãØÈøB ¾‰‚áb¶]ã@“²…,šR}l‡]Ф¡qè µ’‰zˆ|v¦¦Òµ*^ÞGðÿÏßAí.Âò“únz‰‡¦D™óÍgŸ7‘Kf„n˜ý0|ïAÙþ„˜Ö
ñÖ&ØII>…]‘Àc:Ðò)A¾

 

[jaomul]

Slow day?

 

[sm4him]

This makes me wonder if anyone has ever tried to "write" a raw file from scratch and then plug it in as a photo. Hmmm.....could be a new art form? Lol

They already do. Those goofy emotions are evidence that the programmer is smoking his socks while writing the code. He is simply playing with your mind as he creates the image. Sometimes called a "photograph". LOL

Actually, I'm wondering if the smilies aren't just a result of copying and pasting it on TPF, since in every instance that *I* saw, the smilie appears where there should be a ":" followed by a "D" or followed by a "P", which, when put together on TPF, form:

 

[The_Traveler]

This makes me wonder if anyone has ever tried to "write" a raw file from scratch and then plug it in as a photo. Hmmm.....could be a new art form? Lol

They already do. Those goofy emotions are evidence that the programmer is smoking his socks while writing the code. He is simply playing with your mind as he creates the image. Sometimes called a "photograph". LOL

Actually, I'm wondering if the smilies aren't just a result of copying and pasting it on TPF, since in every instance that *I* saw, the smilie appears where there should be a ":" followed by a "D" or followed by a "P", which, when put together on TPF, form:

that's it.
surrounding them with quotes doesn't work.
I could go through the text and enter :d or which seems to work but why bother.

 

[KmH]

This looks like a thread for the Graphics Programs and Photo Gallery forum because it doesn't seem to fit the Photography Beginners Forum description.

There are places in the code the text is the same for some of TPF's emoticons when the code is parsed:
: D (without the space is) : P is the pink emoticon.
So the third line of XML commands in the .xmp file type from the bottom of the file - </rdfescription> - is (with a space added to avoid the emoticon) </rdf: Description>

Raw converters like Lightroom and Aperture do not alter pixels and are known as parametric editors.
The edits we do change values in the Raw converter software line commands that control how the photo is displayed.
Looking at the code we can see the crs: commands are the slider positions used to render the photo.
crs:Exposure="+0.62" is where the Exposure slider in the LR Basic panel was set.

As far as re-editing in another program the edits cannot be exactly reversed because another Raw converter's program would use different sliders and different values for how much edit results from the same amount of slider movement.

As far as that goes, even older versions of LR use different sliders and different values for how much edit results from the same amount of slider movement.
The current version of LR uses Process Version 2012 of ACR (Adobe Camera Raw).
But, in LR 4 and 5 we can choose between using Process Version 2012 and Process version 2010.

 

[JustJazzie]

This below are a few lines at 476111 in a raw file that is 47781 lines long (and that is a small D70 raw file)


‹åë€AŸ›Ÿ 1’=[è$ùuóÿÌÈÏÑ%›–êl¢XZ®Ó‹“Èív|\ÇŽBó¸AÙæµ´.Šã>ã€ÂmªîÿC¹“æ*G¶
‚A§ñs9J'Èjf:VO ç‹H{‹|ƒkÛŒÙY%24º–ÞAéÒn²‘%î_5N0NÕë,ô5#ŏgxì>PߢܙLƒÙî›öî,°ÃҍÛ1Xw‘Î^Üt‹Žæ_ üÁ¡:eŸ_ýë/‰"‘-Ýü'&É1x$yÍïéÙ¯ÌyxóÛ'qJoÚ<€ŠtƒÁã¹Î‘;½S,Íò_yýxgs–†¡ˆäñ(Ñíx~qÂ_#3¼ŽPxØÌê&ùŠA€€Áådžà ´â#⵩!"”‰@Ç~šûa™üµŒGd:”Åé¼’fÚd ‚gj÷9¬çSqЬÑ5]j{™æò¿ë=GÏ7JÛÆò¼M©Lûé¹:ƒˆG ŒÈ勶ãØÈøB ¾‰‚áb¶]ã@“²…,šR}l‡]Ф¡qè µ’‰zˆ|v¦¦Òµ*^ÞGðÿÏßAí.Âò“únz‰‡¦D™óÍgŸ7‘Kf„n˜ý0|ïAÙþ„˜Ö
ñÖ&ØII>…]‘Àc:Ðò)A¾

Yikes! I suppose someone would have to be REALLY bored then.

 

[qleak]

I imagine there is something like this in lightroom.

Darktable has a button to "duplicate" a photo. But what it really does is creates a second .xmp file and adds another database entry for the same NEF file. Talk about saving space!

Some other issues to concern yourself with in raw files is that they store the raw sensor data without demosaicing. So even without compression, it's a very efficient way of storing your photos. If you are unfamiliar with demosaicing it's worth reading about how most digital cameras capture color photographs: A Bayer array

 

[TCampbell]

I'm not sure if this was intended to be a serious question in search of an answer.

Aperture is similar to Lightroom in that the image that comes in from the camera is never touched. Everything you do to adjust the image really goes into a separate file (in Apple's case they maintain a database) -- but it's similar in that when you pull up an image, it grabs the base RAW data, but instantly applies every adjustment you've ever made to it and it does all this before showing it to you not he screen. They do generate "preview" images, which are lower-resolution JPEGs that have the changes applied (you can selectively turn that feature on or off and you can also pick the size of the preview) and this is intended to allow you to RAPIDLY skim through your images without waiting for the computer to process the images before its allowed to show them to you.

There'd be little point in attempt to "write" back to a true RAW file because, as you say, there is no "image" in a RAW file for the same reason that there are no "pixels" on the camera sensor.

If you use a monochrome camera (say.. the "Leica M9 monochrom" - a camera that does't have a color-filter-array (CFA) on the sensor) then the sensor actually has "pixels". But if you have a CFA (every color camera does -- and it's almost always a Bayer mask being used as the CFA) then the camera has no "pixels"... it has "photo sites".

Think of a monochrome sensor except each "pixel" on the sensor is covered with a tiny filter that has a color tint... that filter is either red, or green, or blue and they're not called "pixels", but "photo sites" (more on why in a moment). The Bayer mask is laid out in an array where 50% of the photo sites are green (because the human eye is massively more sensitive to green), 25% are blue and 25% are red.

It looks something like this:

The above is from this page: Bayer filter - Wikipedia, the free encyclopedia

The specific arrangement will sometimes vary by sensor designer, but this is a fairly common pattern.

If you zoom in on any photo, you'd think you should see the individual red, green, and blue squares... but you won't. That's because the RAW data is "de-bayered" to create an image that actually has "pixels" in it instead of "photo-sites". A "pixel" is the combined/blended color value. The "photo site" is just the single red or green or blue element which would eventually contribute to the value of the pixel once the image is "de-bayered".

To de-bayer the image, pick any square. Then "blend" the percentage strength of the surrounding squares into the value of the square you picked and that averages out to some RGB color value (except you give it a weighting -- it's seldom a straight "average"). That resulting RGB value becomes the value of your "pixel" for that position and then you move over a space and repeat... working your way across every pixel square on the sensor.

There are LOTS of de-bayering algorithms. No one algorithm is best. One of my astrophotography image integration & processing apps actually lets me CHOOSE the de-baryering algorithm I want to use.

If you were to take one of your NEF files and process the same file through different RAW handlers (e.g. Nikon software vs. Adobe software vs. Capture One, etc.) and inspect the individual pixels, you'd likely find that the pixel values are different even though they were all generated from the same source NEF.

Now suppose you do a bunch of adjustments... you white balance, maybe you do some shadows & highlights / levels / curves, maybe you do some saturation/vibrance... perhaps a bit of sharpening. And you have this new nice looking image. You really can't easily just "save" that back in NEF form because what you have are a new set of pixels representing the "adjusted" image, but the NEF file doesn't have pixels at all. Suppose I have just ONE pixel in my image that happens to have an RGB value of 44, 117, 202. How would you go about getting that outcome into the NEF file ... especially now that you know that different de-bayering algorithms from the different programs will get a different result?? You'd have to know the algorithm... but all you really know is that you've got the result of some sort of averaging algorithm, but the averaging takes into account the value of surrounding photo sites and those SAME photo sites are used in at least 9 different averaging calculations. So now you're trying to figure out what sort of distribution you need to use to make the math work for all 9 calculations involving that same photo site that would still result in the correct RGB value for each one. If you think about it, it's not a simple process.

If you want non-lossy data that you can transfer to another user, then you either want (a) the original NEF with (b) the sidecar file from Lightroom (assuming they are also a Lightroom user), OR... you want to save the whole thing to a TIFF (which is also non-lossy but actually has "pixels") and send that file instead.

 

[W.Y.Photo]

This below are a few lines at 476111 in a raw file that is 47781 lines long (and that is a small D70 raw file)


‹åë€AŸ›Ÿ 1’=[è$ùuóÿÌÈÏÑ%›–êl¢XZ®Ó‹“Èív|\ÇŽBó¸AÙæµ´.Šã>ã€ÂmªîÿC¹“æ*G¶
‚A§ñs9J'Èjf:VO ç‹H{‹|ƒkÛŒÙY%24º–ÞAéÒn²‘%î_5N0NÕë,ô5#ŏgxì>PߢܙLƒÙî›öî,°ÃҍÛ1Xw‘Î^Üt‹Žæ_ üÁ¡:eŸ_ýë/‰"‘-Ýü'&É1x$yÍïéÙ¯ÌyxóÛ'qJoÚ<€ŠtƒÁã¹Î‘;½S,Íò_yýxgs–†¡ˆäñ(Ñíx~qÂ_#3¼ŽPxØÌê&ùŠA€€Áådžà ´â#⵩!"”‰@Ç~šûa™üµŒGd:”Åé¼’fÚd ‚gj÷9¬çSqЬÑ5]j{™æò¿ë=GÏ7JÛÆò¼M©Lûé¹:ƒˆG ŒÈ勶ãØÈøB ¾‰‚áb¶]ã@“²…,šR}l‡]Ф¡qè µ’‰zˆ|v¦¦Òµ*^ÞGðÿÏßAí.Âò“únz‰‡¦D™óÍgŸ7‘Kf„n˜ý0|ïAÙþ„˜Ö
ñÖ&ØII>…]‘Àc:Ðò)A¾

Yikes! I suppose someone would have to be REALLY bored then.

My friend did a project on this that explores the data created by a camera and how it corresponds to a photo. He made this print of an image and on the back he printed the entire binary code of the image. He also had a recording of himself reading 1 of the 42 pages of code aloud.
Photo Binary — Kei Ito Photography

 

[Nettles]

Heaven help the average beginner wading through this thread.