# Lightroom mobile compressing photos on "export"



## paddycochrane

hi all,

I was under the impression that Lightroom mobile fixed the issue of compressing photos when exporting from Lightroom mobile in version 2.2.

I noticed last night that when I wanted to export (email) a photo from Lightroom the file size was reduced from 24Mb to 8.75mb.

The process I use for importing into Lightroom mobile is as follows:

From Sony a7r2 I wirelessly transfer to iPhone using the playmemories software at original resolution (extra fine jpeg aprox 24Mb). Photo file size on iPhone can be confirmed at this point.

I then import the photos from the iPhone into Lightroom Mobile as per normal. Once in Lightroom  if I immediately try to export/email/upload to drop box the photo to myself the file size reduces from 24Mb to 8.75mb.

Why does this happen, I could expect some reduction in file size is there are any adjustments made, however even without any done the file size is reduced by a 3rd?

Many thanks in advance for any help in this matter,

P.


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## clee01l

What file type is this 24MB original image in Is this a JPEG? If so this is quite huge for a JPEG. Is it a RAW file (ARW)?  Are you Exporting it as an original RAW file? Or are you exporting it as a JPEG which is always lossy compressed?   You use the term "Export" and that option is not available in LR Mobile.  Perhaps you are using the "Share " function (which is controlled by iOS)   If I use "Open In" to save a LR Mobile image to Dropbox.  It gets saved as a compressed JPEG.  No options are provided by iOS to save it otherwise.


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## Johan Elzenga

The OP said it was a jpeg file, and even though 24MB is huge for jpeg, it must indeed be jpeg. It can't be a raw file, because LrM still does not support raw.


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## clee01l

JohanElzenga said:


> The OP said it was a jpeg file, and even though 24MB is huge for jpeg, it must indeed be jpeg. It can't be a raw file, because LrM still does not support raw.


PlayMemories Software is a Sony WiFi App.  It could quite possibly import ARW files from the camera.


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## Johan Elzenga

clee01l said:


> PlayMemories Software is a Sony WiFi App.  It could quite possibly import ARW files from the camera.



Yes, it can indeed. But the OP clearly said "extra fine jpeg aprox 24Mb" and he imported the photos into LrM. _LrM does not support raw import_. The OP also mentioned that he uses a Sony A7R II. My Sony A7R raw files are 37 MB, so the raw files of the A7R II must be more than 40 MB, not 24 MB. So no, these cannot be raw files, they must be (42 Mpixel!) JPEG files at very low compression.


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## paddycochrane

Hi Again,
Many thanks for the input so far on this issue.
Allow me to clarify some points.
The file out of the camera (Sony A7R2) is a JPEG Extra-Fine (Large). I incorrectly said it was around 24MB, I double checked now that I have access to my PC and most of the series of photos taken are in the 18MB to 20MB range and not 24MB as previously stated.
The process for getting the photos from Camera to iphone is as follows:
Wifi connection from Camera to iphone
Connect using Sony Play Memories Application
Copy image size - Original
Select Photos to transfer to iPhone

These photos will then appear in the iPhone Photos App.
As a test, i selected one of the photos and uploaded it to my One Drive Account. The file size was the same as the original photo imported from my camera. This tells me that within iOS the original photo size is maintained and no compression is being applied prior to sending. It's may worth pointing out if any sort of image processing is done prior to sharing, then the image is re-saved and compressed.

I then imported this same photo to my Lightroom Mobile Application.

From lightroom mobile I selected Share (previously referred to as export) and again selected to upload to my One Drive Account. This time the File Size was only 8.75MB. Please note I did this prior to any sort of adjustment/editing being made to the photo. It seems when Lightroom Mobile prepares a photo to be shared, it compresses it to a 3rd of the original size.

I hope the above makes things clearer. Would love to know if this sheds any more light on the issue at hand.

Cheers,

P.


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## clee01l

I think you are seeing different compression levels. The "JPEG Extra-Fine (Large)"  may be referring to the number of pixels and has nothing to do with the level of compression that Sony uses to create the JPEG in the camera.  The Image that comes out of the camera is still a lossy compressed JPEG.  Adobe offers 12 levels of compression for saving JPEGs.  For most purposes compression level 8 (~72 if using LR quality terms) is useful with no visible loss of data.   However, when LR Mobile passes a file to another app (Share), it uses the API provided by iOS. As you can see, iOS does not provide any ability to control the level of compression when creating and passing the derivative lossy JPEG file. You get an Apple defined level of compression.  From your reporting, it appears that the iOS JPEGs are compressed significantly more than the JPEGs that come out of the camera.


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## Jim Wilde

paddycochrane said:


> I then imported this same photo to my Lightroom Mobile Application.
> 
> From lightroom mobile I selected Share (previously referred to as export) and again selected to upload to my One Drive Account. This time the File Size was only 8.75MB. Please note I did this prior to any sort of adjustment/editing being made to the photo. It seems when Lightroom Mobile prepares a photo to be shared, it compresses it to a 3rd of the original size.



What happens after you imported the photo into LRm, did you sync it back to Lightroom on your desktop/laptop? If you did, have you checked the file-size there? It should be the same as the original file in Photos.


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## Johan Elzenga

clee01l said:


> I think you are seeing different compression levels. The "JPEG Extra-Fine (Large)"  may be referring to the number of pixels and has nothing to do with the level of compression that Sony uses to create the JPEG in the camera.  The Image that comes out of the camera is still a lossy compressed JPEG.  Adobe offers 12 levels of compression for saving JPEGs.  For most purposes compression level 8 (~72 if using LR quality terms) is useful with no visible loss of data.   However, when LR Mobile passes a file to another app (Share), it uses the API provided by iOS. As you can see, iOS does not provide any ability to control the level of compression when creating and passing the derivative lossy JPEG file. You get an Apple defined level of compression.  From your reporting, it appears that the iOS JPEGs are compressed significantly more than the JPEGs that come out of the camera.



I agree that it may be a compression difference. "JPEG Extra-Fine (Large)" is the camera setting that produces full size JPEG files at the lowest compression (highest quality) the camera has. When you import these images into LrM and then share (export) them again from LrM, they will be rendered again (to include any edits you may have made, but even without any edits they will be rendered again) and so they will be compressed with new and different compression settings. These settings have indeed nothing to do with the initial JPEG-compression that the Sony camera applied, so it is very well possible that it leads to significantly smaller files.


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## paddycochrane

I would also have to agree that it appears that different level of compression are being applied. I would be interested to know if there would be any noticeable difference in a file that has been compressed from 20MB to around 9MB. I'll run few informal test on my photos to see if there is, however i would like a more scientific opinion from this forum on the matter as well. Im assuming that there must be some degredation, as otherwise what would be the point in having such high MB photos when the same can be achieved for 50% reduction in space saving.

I believe it was mentioned in the thread above that the compression is being handled by iOS and not by LRm, however i dont think this is correct as it seems the compression is done during the time LRm says Preparing Photo (This may take a while). With this in mind does anyone think Adobe Lightroom mobile will ever allow for user selectable compression amount?

One final thing, I was very much under the impression that this very issue was resolved in version 2.2 of LRm, i thought the whole point was that LRm was now able to output/export/share at full resolution. Has this been changed since the last version.

"I’m excited to announce Lightroom for iOS 2.2, which now supports full-resolution output:

_“With version 2.2, we added in the ability for Lightroom mobile to output full resolution files for any file that was either captured on the device or added to the device, either through the camera connection kit, transferred via Wi-Fi from a camera directly, or transferred to the device via services like email, Dropbox, or Google Drive. Additionally, any files that were added directly to an iPhone or iPad are transferred in full resolution to other mobile devices signed into the same account. This way, files captured with your iPhone are available for further editing and exporting from your iPad, in full resolution and vice-versa.” 

Extract taken from Julieanne Kost blog:
Lightroom mobile for iOS 2.2 Now Available with Full-Resolution Output
_


Cheers,

P.


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## DGStinner

Full resolution refers to pixel size (i.e. 2000x3000), not file size.


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## clee01l

paddycochrane said:


> I believe it was mentioned in the thread above that the compression is being handled by iOS and not by LRm, however i dont think this is correct as it seems the compression is done during the time LRm says Preparing Photo (This may take a while). With this in mind does anyone think Adobe Lightroom mobile will ever allow for user selectable compression amount?


  I don't think LR Mobile has the code included to create and compress a JPEG.  To save storage, those functions common to many applications are considered a part of the iOS API and are simple called by LR.  Compression is still done but it is iOS that does it.


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## paddycochrane

DGStinner and Clee - Many thanks for you input into this issue, you have helped a lot in getting to me to understand the process of whats happening.
Initially I was annoyed that my photos were being seemingly reduced in resolution by a substantial amount (75%), however I know understand that the process is just compression and does not affect the resolution and quality of the photos (to a noticeable degree).
I feel more comfortable now knowing that my photo are retaining their full resolution.
Cheers,
P.


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## clee01l

> does not affect the resolution and quality of the photos (to a noticeable degree).


It does not affect the resolution (you still have the same number pixels  even if you don't have the same pixels out that were there before compression.) It does affect the quality. lossy compressed files created from already lossy files are even more compressed and even more pixels are irretreiveably tossed out for the sake of a smaller file.  Two or three generations removed from the original raw data may not be visually noticeable but do affect the results of future processing algorithms.  Five or six generations removed from the original can be visibly detected.


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