LR Classic Exporting

[CanadianJake]

When exporting an image from LR Classic, it saves at 2mb. My original file is 18mb. How can I have the file export at about 8mb?

[Manfred M]

I assume that you are saving as a JPEG? What is the "magic" about wanting a 8MB file?

The JPEG is a compressed format and is using "lossy" compression where the original raw capture, which is stored as a 16-bit file is converted to 8-bits. Depending on the quality settings on your camera (I can choose High, Normal and Basic) and have even more choices if I use my raw convertor, additional compression can be used.

My 36.1MB sensor creates 38MB raw files (there is overhead from the metadata that is written to each file) and when I choose the "Basic" setting for JPEG, those files run in the 1 MB to 1.5MB range.

I don't use Lightroom, but expect that you set the quality in the Export settings and these settings will ultimately impact your file size.

[pschlute]

I resize my jpeg files to 1440 pixels tall for screen viewing and posting to the internet. They all come in at less than 2 MB file size.

Only time they are significantly larger is when I prepare an image for print, when the pixel dimensions will be much larger and so will the MB size.

Why do you want a larger file size ?

[DanK]

When exporting an image from LR Classic, it saves at 2mb. My original file is 18mb. How can I have the file export at about 8mb?

Assuming that you aren't constraining the size in pixels as Peter noted, the size of the JPEG is determined by the quality level you select. Select the highest quality and uncheck any limitations on pixel size, and that will give you the largest JPEG you can get.

[Ken MT]

With lightroom a 24MB file (CR2), exported as a Jpeg was 3.0, with no constraints, and as a TIFF was 20.7MB. Increasing the file size exported as a Jpeg to 4800 x 3600 gave me a file size of 8MB.
Exporting a 4.5MB Jpeg file as a TIFF, gave a 50MB file.

[pschlute]

Exporting a 4.5MB Jpeg file as a TIFF, gave a 50MB file.

I think it is probably worth expanding on this example to show that file size itself is no indicator of more quality or resolution.

TIFF files by their nature are large files, especially if layers are preserved during the save. They can be 16 bit files.

JPEG files can only be 8 bit files. They are also a "lossy" format. If you export or save a JPEG file as a TIFF, you are only increasing the file size, with no compensation. You cannot get back 16 bits of colour that were lost when the JPEG was originally created.

Now this does not mean we should all be using TIFFs instead of JPEGs. The latter file type is the standard for use on the internet and for many commercial printers (save for some specialist pro applications). A JPEG is completely suitable for this.

Where TIFF files are useful is for PP work. Having converted a RAW file it is best to save the image as a TIFF if one wants to more work like selective tonal or colour adjustments on the image. This is because you are working in 16 bit with no loss of data each time you save. When the PP work is complete and you intend to post to the web, you should save as a JPEG as the last stage.

[DanK]

With lightroom a 24MB file (CR2), exported as a Jpeg was 3.0, with no constraints, and as a TIFF was 20.7MB. Increasing the file size exported as a Jpeg to 4800 x 3600 gave me a file size of 8MB.
Exporting a 4.5MB Jpeg file as a TIFF, gave a 50MB file.

I think you did something wrong. Decreasing output file size in pixels should decrease file size in MB.

To double check this, I just exported a 37.4 MB raw file (Canon CR2) as three JPEGs. Here are the results:

--quality 100, unlimited size: 19.9 MB

--quality 100, limited to 4800 x 3600: 10.1 MB

--quality 87, unlimited size: 13.4 MB.

Why 87%?

If you look at Jeffrey Friedl's site, http://regex.info/blog/, you'll find a test of LR JPEG quality levels. He had two conclusions. The first is that although the LR scale has increments of 1, there are only 6 or 7 actual quality levels. Second, the quality you get at a setting similar to the 87% I used is pretty much indistinguishable from 100% on screen, and the file size, as ou can see, if far smaller. So for posting on screen, I leave LR set at 87. In the rare instances when I send a JPEG out for other uses, I set it to 100.

Peter's point is essential. Once you have discarded data by converting to JPEG, you don't get it back by converting again to another format. And the lower the quality setting, the more data you have permanently lost. For that reason, I use JPEGs only when they are needed, and I convert to JPEG only at the very last step.

[Chataignier]

I would still like to know why you want an 8Mb file ?

8Mb is a bit small for print and way too large for internet (on screen viewing) use...

For example, the jpeg files I post here are normally 2000px wide to suit an HD screen and typically between 500kb and 1Mb.

PS : I have assumed you are exporting as a jpeg file, is that the case ?

[lunarbo]

First check how you are exporting from LR, you may have a setting inadvertently incorrect for your use

On the top line of the LR Develop page ...
File ----> Export........

This opens to a box with different headings - export location, file naming, file settings, image settings etc

Check file settings and image settings as these can be configured to suit your purposes.