Just in the last few days, LR has thrown me a curve. I am trying to export several photos taken with a full-frame Pentax. LR tells me the pixels are 7360 x 4912, which makes 36.2 MB. In the export window, I limit file size to 29 MB [because my Websites have a limit of 30 MB].
Suddenly, when I hit the Export button, I always get an error message saying "If an image cannot meet the limit, then it will be exported to the minimum possible file size" [see attachment].
A couple of times when I ignored that and hit "Continue," I ended up with 22 MB or so exported files; they look OK to me.
I tried messing with the file limit in the Export window, everything from 1.5 MB to 300 MB; didn't matter, I keep getting the same error message.
How do I fix this? And what limit is in question, and is it a minimum or a maximum?
It is possible that if you are not resizing (down) the pixel dimensions of the exported image, then the JPG compression cannot 'fit' all those pixels into the smaller file size. ie. 7360 x 4912px will simply not compress to 29MB?- unless LrC uses a lower compression quality. At a lower quality you are possibly getting the 22MB file.
To achieve "everything from 1.5 MB to 300 MB" then you MUST also resize the pixel dimensions (eg. 1024x768px) for the exported file.
Be aware that the "Limit" box is for Kilobytes! 1000KB = 1MB.
Are you sure you are using 29,000 KB for a file <29MB?
Thanks, Rob. It is my impression from the export window that if one specifies a maximum file size (without moving the “quality” slider), then it will choose the maximum quality compression that will fit within the specified maximum file size.
My phrase "everything from 1.5 MB to 300 MB" was meant to say that I had put all of those maximum file sizes into the export window, and nevertheless always got the warning message.
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That message was added to the latest release, just to inform you. It is not an error message.
You cannot compare file sizes between raw and jpg. Raw is one color per pixel, jpeg is three colors per pixel. Raw is 14 or 16 bits per color, jpg is 8 bits per color. Raw is either not compressed at all, or perhaps compressed with a lossless compression. Jpg is lossy compressed. In other words, there is nothing to fix. If your image looks good and is within the parameters, then Lightroom Classic did what it needed to do.
Thank you, Johan. The info that it was in the latest release explains why it started suddenly and is happening to all my exports.
BUT - I still do not know what it is warning me about. Is it trying to warn that IF the RAW file being exported cannot be compressed into a jpeg as small as the maximum size one has specified in the export window, THEN it will be exported to the smallest jpeg possible, even though that exceeds the maximum jpeg file size specified??
If so, there must be several ways to better express that. And I would much prefer if LR could wait until it has done the calculation, and only warn if that is the case, rather than warning each and every export.
You have confused megapixels (MP) and megabytes (MB). These are not the same, and there is not necessarily any relationship between the two when exporting JPGs.
LR tells me the pixels are 7360 x 4912, which makes 36.2 MB.
That is wrong. You do not have 36.2 MB. You have 36.2 MP.
In addition, when you export a photo as a JPG and get (for example) 10 megabytes, please know that megabytes is not an indicator of quality of the image. The quality of the image can be determined by LOOKING AT IT with your own eyes. Do not say 10 MB is not enough. A 36 MP image should look fine if the export is 10 MB. It may even look fine at 2 MB, because JPG is a compression technology, it does a very good job of compressing images so that there is (hopefully) no noticeable loss of quality. Please read http://regex.info/blog/lightroom-goodies/jpeg-quality
Thank you, dj_paige. You are correct, I was confusing megapixels with megabytes. And thanks for straightening me out on how a large megapixel file can still look good at a moderate jpeg file size.