# Exporting DNG from cropped TIF files



## Dick.E.Hoskins (Jun 5, 2018)

I scan old slides in tif format.  They are quite large because of resolution and color density I select on my scanner. I then load the tif files in to LR and adjust the cropping. (The boundary of the slide holders when scanning becomes part of the  resulting scanned image.  I crop the scanned image in LR and export to a DNG. The DNG is much smaller and (I hope) offers flexibility in post processing. (not so sure this is true for a scanned image)  However when I look at the resulting DNG image in LR the output image has not been cropped.  I opend the DNG file in another package and the image cropping had not been applied in the output process in LR.  How can I export the tif to a DNG and have the cropping I apply in LR applied to the output DNG image?


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## BarrySchwartz (Jun 5, 2018)

I can't address your question here about why the photos are not cropped - that seems pretty weird to me, also - but I will comment that I make all my scans as DNGs, which makes post-processing infinitely easier all around.  I use VueScan, which is a dynamite, inexpensive, and constantly updated software I've used for years, which will work on virtually ever scanner made in the last four decades.  VueScan has all kinds of useful settings, and will also scan in TIF, JPG, and PDF.


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## PhilBurton (Jun 5, 2018)

Barry,

Just wondering.  Have you ever compared VueScan with Silverfast?


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## Gnits (Jun 5, 2018)

I suspect the dng is holding the original tiff plus the crop info.  

If you want to crop and remove the surplus pixels open in Photoshop and crop there. You can save back as a tiff or a number of other formats.  I do not use dng so do not want to comment on its features.  Maybe saving as compressed tiffs might save you the space you found from saving as dng.


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## Dick.E.Hoskins (Jun 5, 2018)

I used SIlverfast - lots of things to twiddle and manipulate before making a scan but I found it to be time consuming and easy to forget. I have read in several places that one should scan the slide first and THEN post process (rather than pre-process) . One of those places was a professional photo scanner's website. The only pre-processing I use is scratch and "dirt/ dust" removal which takes longer but seems to work. I will definitely check VueScan. Thanks!


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## Dick.E.Hoskins (Jun 5, 2018)

Gnits said:


> I suspect the dng is holding the original tiff plus the crop info.
> 
> If you want to crop and remove the surplus pixels open in Photoshop and crop there. You can save back as a tiff or a number of other formats.  I do not use dng so do not want to comment on its features.  Maybe saving as compressed tiffs might save you the space you found from saving as dng.



Is using a compressed tiff back to the lossy problem as in a jpeg ? My scanner will make them; I have not tried.


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## BarrySchwartz (Jun 5, 2018)

PhilBurton said:


> Barry,
> 
> Just wondering.  Have you ever compared VueScan with Silverfast?



I have not used Silverfast, which I understand is a good program, but it's very expensive and as far as I know (which is little, since I've never used it), there is very little it can do that VueScan can't.  There may be issues Silverfast can handle, such dust and noise removal that are not the same in VueScan; however, LR is pretty good these days on those fronts, and other programs such as OnOne or the soon-to-be revived Nik programs do a good job, as well.


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## Hal P Anderson (Jun 5, 2018)

Richard Hoskins said:


> Is using a compressed tiff back to the lossy problem as in a jpeg


JPEGs use lossy compression. Compressed TIFFs don't, so they don't run into the degradation that repeated saves of a JPEG cause.


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## Dick.E.Hoskins (Jun 6, 2018)

Hal P Anderson said:


> JPEGs use lossy compression. Compressed TIFFs don't, so they don't run into the degradation that repeated saves of a JPEG cause.



Can LR read compressed tiff files?  Mr Google reveals little.  I am thinking likely not.


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## Johan Elzenga (Jun 6, 2018)

Richard Hoskins said:


> Can LR read compressed tiff files?  Mr Google reveals little.  I am thinking likely not.


Yes, it can (at least for LZW compression).


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## Michael Naylor (Jun 7, 2018)

LZW doesn't support 16bit.  Sometimes the LZW can be larger than then compressed version.  I went through loops on this topic and concluded uncompressed was the most portable.  However, once happy with the crop & development, one can export out in JPEG.


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## Johan Elzenga (Jun 8, 2018)

Mike Naylor said:


> LZW doesn't support 16bit.  Sometimes the LZW can be larger than then compressed version.  I went through loops on this topic and concluded uncompressed was the most portable.  However, once happy with the crop & development, one can export out in JPEG.


LZW supports 16 bits as well, it's just not effective (and can indeed sometimes even increase the file size). The question was whether Lightroom can *read* compressed tiffs however. It can, even if you were so silly to use LZW on a 16 bits TIFF file.


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## Michael Naylor (Jun 8, 2018)

OK.  So LZW doesn't support 16 bit very well.


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## Dick.E.Hoskins (Jun 16, 2018)

Gnits said:


> I suspect the dng is holding the original tiff plus the crop info.
> 
> If you want to crop and remove the surplus pixels open in Photoshop and crop there. You can save back as a tiff or a number of other formats.  I do not use dng so do not want to comment on its features.  Maybe saving as compressed tiffs might save you the space you found from saving as dng.



DNG is less than 1/2 the size of tif.


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## BarrySchwartz (Jun 16, 2018)

DNGs are something like a 7th the size of a 16-bit TIF, and don't hold or contain the original TIF; once a RAW file is exported (not converted), that's it.    The remaining DNG has a real advantage - as does any RAW file - in that you can always go back to the beginning and start all over again any time with no loss in quality; you can change how it looks and exports, but you can't change the foundation of the file itself.   Over time, as software gets better, the original DNG can be processed better - I've improved images I took 10 years ago by starting all over again.  DNGs have other advantages, such as the ability to hold vast quantities of metadata, along with the ability in LR to verify if it's been corrupted or not, particularly copies, backups, and that sort of thing.


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## Johan Elzenga (Jun 16, 2018)

This thread is not about raw files. It is about scanned tiff files. DNG can containt RGB data as well,  but that does not make it a raw file and does not give you the special options of a raw file. A DNG that was created from a TIFF is just a TIFF in another envelope.


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## BarrySchwartz (Jun 16, 2018)

Sorry, I assumed the original post was about scans, and my first comment was that one can make scans as DNGs, so I was continuing that thought, and trying in my most recent comment to address what I thought was some confusion about the difference between TIFs and DNGs.


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## PhilBurton (Jun 20, 2018)

JohanElzenga said:


> This thread is not about raw files. It is about scanned tiff files. DNG can containt RGB data as well,  but that does not make it a raw file and does not give you the special options of a raw file. A DNG that was created from a TIFF is just a TIFF in another envelope.


Johan,

Assuming that scanning software can create a DNG, as opposed to a TIFF file, is there any advantage at all to having the DNG file, especially before doing any editing (like spot removal) on the DNG?

Phil Burton


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## Johan Elzenga (Jun 20, 2018)

PhilBurton said:


> Johan,
> 
> Assuming that scanning software can create a DNG, as opposed to a TIFF file, is there any advantage at all to having the DNG file, especially before doing any editing (like spot removal) on the DNG?
> 
> Phil Burton


It depends a bit on the DNG. A scanner normally creates RGB files because it does not have a Bayer filter, but some scanner software can create  a 'raw' file that contains linear RGB plus the infrared dust detection data channel. There are some advantages in that, but you could still save this in DNG or TIFF, so the file format itself isn't really the issue. See Scanning: Archival Scan Formats


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## ocanannain (Jun 20, 2018)

BarrySchwartz said:


> I can't address your question here about why the photos are not cropped - that seems pretty weird to me, also - but I will comment that I make all my scans as DNGs, which makes post-processing infinitely easier all around.  I use VueScan, which is a dynamite, inexpensive, and constantly updated software I've used for years, which will work on virtually ever scanner made in the last four decades.  VueScan has all kinds of useful settings, and will also scan in TIF, JPG, and PDF.


I've gotta give a great big "thumbs up" for VueScan. It allowed me to bring back to life a wonderful older scanner that I now use frequently.


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## PhilBurton (Jun 23, 2018)

JohanElzenga said:


> It depends a bit on the DNG. A scanner normally creates RGB files because it does not have a Bayer filter, but some scanner software can create  a 'raw' file that contains linear RGB plus the infrared dust detection data channel. There are some advantages in that, but you could still save this in DNG or TIFF, so the file format itself isn't really the issue. See Scanning: Archival Scan Formats


Johan,

BIG, BIG, BIG thanks for that article you referenced.  I found it very helpful and informative.

Phil Burton


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