# Exporting Master vs Virtual Copy



## David PZ (Jul 24, 2017)

Just a basic question. I export my master JPEG file each time to the lab in order not to deal with virtual copies. As I understand, if there is deterioration of the image, it would affect the exported image and not the master – am I right? Of course, exporting a virtual copy of the master would set my mind completely at ease. Thanks in advance for your answers.


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## clee01l (Jul 24, 2017)

Not exactly.  A Master copy and a Virtual Copy are two different sets of develop instructions for the same original image.
If you shoot JPEG in the camera, the JPEG produced by the camera from the RAW image represents a lossy copy of the original RAW data.   This is considered a first generation lossy JPEG.  When you open this JPEG in LR or any other app, the pixels that you get when decompressed are not the same pixels that were created by the camera because compression loses pixels and this results in a loss of quality. 
If you shoot RAW and export a JPEG, this new file is also considered a first generation lossy JPEG.  The same level of JPEG quality that a JPEG from the camera would have possessed. 
However, If all you have from from the camera is a first generation lossy JPEG and this is imported into LR, Any exported JPEG will then be considered a second generation lossy JPEG. and even more pixels get lost in the compression. If you have a second generation lossy JPEG in LR and you export it the result is a third generation lossy JPEG with even more data loss.  This data loss does not become noticeable with the human eye until about the fifth generation JPEG but it exists none the less and something called JPEG artifact can be introduced in the processing.

So, the best JPEG that you can produce is always going to be lossy and the best JPEG that you can generate is going to be the first JPEG produced from the RAW image.  In LR is does not matter whether the source of your edit instructions is the master copy or the virtual copy.  They both will use the original lossless RAW data to create the JPEG.


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## David PZ (Jul 25, 2017)

Thanks Cletus. I want to be sure that I understood everything, for this is important for me to know. 

A. I shoot with an iPhone, so the JPEG created is a 1st generation JPEG. Questions: (1) When I import it into LR, does it become a 2nd generation JPEG or still remains 1st generation? (2) Next, when I export it to my desktop, does the exported copy on desktop become another generation away? Am I right in saying that the master in LR is no longer affected and only the exported copy on desktop suffers further loss? (It this were not true, then the master's life in LR would be limited, for I would not be able to keep ordering prints this way anymore.)    

B. By the way, yesterday I exported to desktop a bunch of files with the wrong template, so I re-exported them again and I found that each time I had to click Save and again export and click Save a second time to get LR to respond to me if I want to replace the existing file. Just wonder if that further degraded the images.

C. Last question. When I upload the images into the ROES at the lab, do they lose quality one more time?


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## clee01l (Jul 25, 2017)

JPEGs imported from the iPhone are 1st Generation.  Any LR Export from that 1st generation Jpeg will become a 2nd Generation JPEG.  That is to say that any Save from any editor will be a derivative of the original that it is saved from (One generation removed from its source data).  Copies of the original are byte by byte data duplicates and won't exhibit any more lossy compression than the original does. 

Master and virtual copies refer only to the develop instructions in LR. They refer to the same source image. That source image remains as it was when the JPEG was copied to the disk on import.  There are lossless formats like TIFF  You can process a 1st generation JPEG in LR and export it as a lossless TIFF.  This TIFF can't replace the data lost when the JPEG was compressed during creation but it won't lose any more data if it is losslessly compressed. 

B. You were exporting a second time from the original JPEG,  So the first (bad template) and the second export JPEGs were both 2nd Generation JPEGs So no additional data was lost with the duplicates export. 

C.  The file that you upload to the ROES Lab is a copy of the JPEG created during export. It is a duplicate and will have the same data characteristics as the copy that remains on your computer.


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## David PZ (Jul 26, 2017)

Your answers are most helpful. Thank you. If you can tell me that the following statement is correct, then I have understood you correctly.

"I can export a 1st generation JPEG original from LR to desktop again and again or send the exported 2nd generation JPEG to my lab again and again, and the exported JPEG will remain as a 2nd generation JPEG and my original will remain as a 1st generation JPEG."


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## clee01l (Jul 26, 2017)

David PZ Wong said:


> "I can export a 1st generation JPEG original from LR to desktop again and again or send the exported 2nd generation JPEG to my lab again and again, and the exported JPEG will remain as a 2nd generation JPEG and my original will remain as a 1st generation JPEG."


You have understood correctly.   Whenever a JPEG is created from a source, there is compression and data loss.  When ever a new copy is made of a JPEG that already has been created there is no (further) data loss.


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## Dan Marchant (Jul 26, 2017)

There is one other thing to consider and that is your export settings. Specifically the Quality setting. To maintain maximum quality you should ensure that the quality setting in LRs Export dialogue is set to 100, otherwise the (2nd gen) file that LR creates will be further compressed (compared to the 1st gen original) which will reduce quality.


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## David PZ (Jul 26, 2017)

Thanks, Cletus. You've made my day. Now I can go full speed ahead to get all my prints made.

Thank you, Dan, too. Yes, I do set the quality to 100, altho the lab recommends 85, as I recall. I think they believe that visually, you wouldn't be able to see the difference. BTW, I read that these ranges set in LR would give you exactly the same file size: 93-100, 85-92, 77-84, 70-76, 62-69, 54-61, etc. This is indication to me that even if you specify 100, the image still gets further compressed.

This question perhaps should go on a different thread. As you know, in removing spots, if there are a lot of spots already touched up, it's hard to create another circle among these circles for lack of space. In that case, I just start a circle close by and drag it to the tight spot to touch up. Some time ago, I read online twice about a cool way to not only make all previously spots disappear, but also enables you to click anywhere to start a new circle. Now I've forgotten the key(s) to click or hold to do that, and I couldn't find the sources online again. So I just wonder if any of you know this neat trick and can share with all here.


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## Hal P Anderson (Jul 26, 2017)

Oddly enough, Johan answered that question for another forum member earlier today: set Tool Overlay to 'Never' on the toolbar underneath the image when you're in Spot Removal mode. It works in version 6, but I wasn't able to make it work in 5.7.


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## David PZ (Jul 27, 2017)

Hal, I know about the the 'Never' overlay setting – it doesn't work in 5.7; but the trick I read was different, for it actually worked in my LR version.


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## Hoggy (Jul 28, 2017)

David PZ Wong said:


> This is indication to me that even if you specify 100, the image still gets further compressed.



Yes, even at 100%, it will still get compressed again..  Or more accurately, losses will still occur.  It's been a while since I've exported a jpeg of a jpeg, so I don't know exactly how much more compression will happen.  Especially at 100%, it's possible it might even be bigger, considering that LR is working with the data after it's been uncompressed and then incorporating your develop alterations _to_ that data - then compressing the end result.  ...  But I think I read that too, about the compression ranges bit - maybe by Jeffrey Freidl(sp?), AKA - JF.

A way around the 2nd generation dilemma would be to select 'original' in the export options..  That will export an exact copy of the original jpeg image data (_meta_data could still differ), without any develop edits - therefore still being the 1st gen.  That might be useful for you if you find the original doesn't need any develop edits anyways.



David PZ Wong said:


> Hal, I know about the the 'Never' overlay setting – it doesn't work in 5.7; but the trick I read was different, for it actually worked in my LR version.



I think I saw mention of such a trick in the thread Hal talks about.  Something about selecting an area outside of the needed area, and then moving moving the end spot..??  It would work on the principal - in which I keep finding out, but keep forgetting specifics  - that only either color/brightness or texture is being copied when using heal..  Or it goes _something_ like that, anyways..  Someone with a clearer head than mine might be able to expand on that.


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## David PZ (Jul 28, 2017)

Hoggy, after reading your second paragraph above, I get a little confused. All I know is that whatever you do in LR is nondestructive, so whether you edit the original image or not, it is exporting (saving) the file that compresses the JPEG.

Cletus mentioned converting JPEG into TIFF first. But when I export it from Print module, doesn't it get changed back to JPEG again? Besides, my lab accepts only JPEGs.


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## Hoggy (Jul 28, 2017)

David PZ Wong said:


> Hoggy, after reading your second paragraph above, I get a little confused. All I know is that whatever you do in LR is nondestructive, so whether you edit the original image or not, it is exporting (saving) the file that compresses the JPEG.



When setting the option 'Original' in the export dialog, it's the only exception in which it doesn't [re]compress the image data.  It's basically a file-system type copy, in which there is no compression or recompression involved.  The only possible change could be in the metadata, which if you've set the option to write metadata into the original jpeg XMP, will actually write it into the original.  The original's *image* data will never be changed though.  XMP is something that may 'live' within some file types - it may be in the same physical file, but it's separate from any image data.
Of course, when using that 'original' setting from the dropdown, no edits from Develop module will show up - because it's for all intents and purposes, a file-system type copy.




> Cletus mentioned converting JPEG into TIFF first. But when I export it from Print module, doesn't it get changed back to JPEG again? Besides, my lab accepts only JPEGs.



What I think Cletus is referring to, is if you take the original 1st-generation jpeg and convert(export) it to a TIFF - and then, for instance, re-import that TIFF into LR and make image edits, any further jpeg exports from that point on from that TIFF will always be 2nd-gen jpeg.  IOW, the TIFF might be likened to a raw file at the point it's made.  As far as I know, there is no lossy compression for TIFF's - certainly not in LR there isn't.


As for exporting from the Print module - I've never actually printed anything..  But looking at the Print Module, I don't see an export option.  So either you're referring to 'printing to a file' in the Print dialog that would pop up after pressing 'Print/Printer', or you're actually choosing "Export" from the "File" menu in the top menu-bar - which is actually the standard Export dialog that would show up from any module.


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## clee01l (Jul 28, 2017)

David PZ Wong said:


> Cletus mentioned converting JPEG into TIFF first. But when I export it from Print module, doesn't it get changed back to JPEG again? Besides, my lab accepts only JPEGs.


You can not export from the print module.  You can only "print" to a file.  This is not the same as creating a derivative JPEG or TIFF using the Export function found on the "Edit" menu. 
IMO Print Labs that do not accept lossless TIFFs are willing to accept some loss of quality in the files that they receive.  For many people that use 3rd party print labs only work with JPEGs as a source.  Since the  actual date loss is not visible to the naked eye until about the 3rd or 4th generation of compression, this is acceptable to most people.   My standards are higher. If I use a 3rd party print lab, I only use those that will accept the highest quality lossless TIFF using a wide gamut color profile (i.e. not sRGB).  Anything less than that, I can do myself in the print module up to the paper size limits of my printer.


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## David PZ (Jul 29, 2017)

Hoggy, again I am learning something new. Are you saying that the 1st generation original JPEG remain 1st generation even after being exported? But that option with no edits allowed may not be practical.

I've been exporting the file by clicking Print to File in the Print module because from Library, I don't know how to control borders when exporting to a lab. In Print module if I go to File in the top menu bar and choose Export, I get the same form as from the Library and the image saved is stripped of borders.

Cletus, Before sending the image to the lab, so far I've been using Print to File (which frankly I didn't understand what it did) and save the image to Desktop. How is this image saved different from the image saved through Export, if any?


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## clee01l (Jul 29, 2017)

David PZ Wong said:


> Are you saying that the 1st generation original JPEG remain 1st generation even after being exported?


No, Exported means the the original has been decompressed and pixels that were lost in compression are thrown away before the image was decompressed and got to LR.  When this decompressed image is saved to a new file, it is compressed and more pixels are lost.  ONLY files that are copies retain the same data quality as the file there were copied from.


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## Hoggy (Jul 29, 2017)

David PZ Wong said:


> Hoggy, again I am learning something new. Are you saying that the 1st generation original JPEG remain 1st generation even after being exported? But that option with no edits allowed may not be practical.



I think me and Cletus are talking about different things..  Either that or I'm confused, too.   But yes, that is the case, *ONLY* when selecting *"Original"* as the *"File Settings"-"Image Format"*.  It outputs whatever the original file is, as it is.  If the original is a DNG, it will output the DNG, as it is.  If it's a TIFF, it will output that tiff, as it is.  ......  When selecting it, you'll see that almost all other settings (namely, anything relating to image data changes) in the dialog will suddenly grey out, not allowing any changes..   That's because the image data is a bit-for-bit exact copy.

But that's why I say it may only be useful in circumstances where the original, as it came out of whatever camera or device, is 'good enough' for a print (or email, etc..).


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## clee01l (Jul 29, 2017)

Hoggy said:


> But yes, that is the case, *ONLY* when selecting *"Original"* as the *"File Settings"-"Image Format"*. It outputs whatever the original file is, as it is.


When that parameter is chosen, Export does not work with the image (as seen on the screen), apply LR adjustments, crops, etc but instead does a simple FILE copy using the filesystem function "COPY"  which is perhaps easier done using Finder/Explorer.


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## Johan Elzenga (Jul 29, 2017)

clee01l said:


> When that parameter is chosen, Export does not work with the image (as seen on the screen), apply LR adjustments, crops, etc but instead does a simple FILE copy using the filesystem function "COPY"  which is perhaps easier done using Finder/Explorer.



That is not entirely correct. In case of a proprietary RAW file, 'Export Original' exports an XMP file as well. If the original is DNG or some RGB format (tiff, psd, jpeg) I assume it adds the edits (and other added metadata like keywords) to the metadata of the exported file (but I never checked that).

UPDATE: I just checked it for a TIFF file, and a keyword that I added just seconds before using 'Export Original' was indeed included in the metadata of the exported tiff file. So 'original' isn't 100% correct if it's not proprietary raw...


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## clee01l (Jul 29, 2017)

JohanElzenga said:


> I just checked it for a TIFF file, and a keyword that I added just seconds before using 'Export Original' was indeed included in the metadata of the exported tiff file. So 'original' isn't 100% correct if it's not proprietary raw...


Hopefully, what Hoggy says about exporting original does mean that the data block (pixel part of the image) is copied from the old file to the new and a metadata wrapper is updated


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## Johan Elzenga (Jul 29, 2017)

clee01l said:


> Hopefully, what Hoggy says about exporting original does mean that the data block (pixel part of the image) is copied from the old file to the new and a metadata wrapper is updated



Yes, I'm pretty sure that's how it works. The creation date of the exported file is the old creation date, that also confirms it.


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## Hoggy (Jul 29, 2017)

Yes, the metadata wrapper is the only thing that could be different from what came out of camera.  If one writes the metadata into the file types that support it (or XMP in proprietary raw), it will be written to the original [XMP] and therefore be output as such.

Another way it can be useful: I somewhat recently used it to make DVD's of family members in my immediate family, for the familial 'genealogist'.  I made one with the edits applied and one as the originals before editing.  It would have been tough hand-picking them out in Exporer/Finder, but that originals option did the trick easily.


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## Johan Elzenga (Jul 29, 2017)

The only thing you have to remember is that Lightroom will write the edits to the metadata, and Adobe software can read that and apply it on opening. So if the original is DNG, then the edits will be read when you open that exported 'original' DNG again in Lightroom or in Photoshop/Camera Raw. That means that Lightroom and Camera Raw will not display the unedited original, but the edited one. Of course you can still simply reset that, but it's good to remember this. Especially when you send such a DNG to somebody else.


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