# Lightroom Web image download size?



## prbimages (Aug 22, 2017)

I have read that Smart Previews are 2560 pixels along the long edge.

I have read that Smart Previews are used to sync to Lightroom mobile (although I do not use Smart Previews at all on my desktop).

So why is the image download size offered to me via Lightroom Web 2048 pixels, and not 2560 pixels?


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## clee01l (Aug 22, 2017)

Because you remembered wrongly.  2048px (1024X2) is the correct long edge.  A standard HDTV display is 1920X1080 and 2048 pixels matched this resolution most closely without too much overhead, Both 1920 and 2048 are factors of 128.


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## prbimages (Aug 22, 2017)

Thanks Cletus! However, I am not "remembering wrongly", I am quoting stuff I've read. Specifically, Victoria's latest post. I wasn't sure about the figure she mentioned, so I did a brief web search, and found a few other references to 2560 pixels as well (e.g. in this thread, although none of them were "official" figures), and none for 2048, so I thought something strange was going on. Good to have it cleared up.


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## prbimages (Aug 22, 2017)

Some other references to Smart Previews being 2560 pixels on the long edge:

Lightroom Queen
Mulita.com
Jim Wilde in this thread
Thread on dpreview


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## Jim Wilde (Aug 22, 2017)

Yes. Smart previews are indeed 2560 on the long edge, and also yes LR Web shows a 2048px jpeg, not the smart preview (which is a linear DNG, IIRC). There's probably a good reason for this difference but if so I can't remember what it is.


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## prbimages (Aug 22, 2017)

Thanks Jim, yes, I've since done some of my own testing and confirmed that smart previews, at least _in the desktop environment_, are in fact 2560 pixels on the long edge. Strange indeed, then, that the LR Web JPG download is only 2048 pixels. On Android mobile, a download gives you the option between "limit to 2048 pixels" and "largest available", but "largest available" is still only 2048 pixels. I guess it is conceivable that the smart previews which are used for online syncing might be different (smaller) than the ones which are used on the desktop. Whatever is happening, it seems a bit odd.


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