Why is my JPEG export only 8.4MB, and is it too low quality for printing?
Asked 11/8/2017
3 views
2 answers
0
I shot a night photo in RAW at ISO 100, f/16, 30 seconds, edited it in Lightroom, and exported it as a JPEG for printing. The exported file is only about 8.4MB, and the print site warns that it may be too low quality. Export quality is set to 100 and resolution to 300 dpi. Is this normal for a JPEG, or am I exporting incorrectly? Should I check anything specific in Lightroom before sending it to print?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
8y ago
2 Answers
3
The print site is most likely just using a simple algorithm to check the file for compatibility to print well. That being said, I'm unsure why they would be making this determination off of file size alone. As has been commented, jpg compression can work wonders in shrinking a file. Given that your image is mostly dark and 1/5(ish) of it is dark sky - your file size is probably the result of the compression. There's nothing inherently wrong with this.
The print site could actually be looking at the amount of file data instead to make it's determination, asking itself, "is there enough data here to print?" I imagine it could be looking at your intended print size, the photo's length and width in pixels, and the resolution - and then determining to alert you to make sure the file is large enough.
You would need to post the actual file you're attempting to print, or at least it's dimensions and resolution, along with your intended print size for anyone to advise further.
Oh, and nice shot!
Originally by user67377. Source · Licensed CC BY-SA 4.0
user67377
8y ago
0
Generated from our catalog & community — verify before relying on it.
An 8.4MB JPEG is not automatically too low quality for printing. JPEG file size depends heavily on image content and compression; photos with large dark or simple areas often compress very efficiently, so a night image can end up surprisingly small without being low resolution.
What matters most for print is the image’s pixel dimensions, not the MB size. The print lab may be warning based on print size versus available pixels, or it may just use a simple automated check.
In Lightroom, the main thing to verify is that you are not resizing on export. If “Resize to Fit” is enabled, turn it off so the JPEG exports at your camera’s full native resolution. Keep JPEG quality high (around 90–100 is fine). The 300 dpi setting usually does not meaningfully affect image quality by itself; pixel dimensions are the important part.
Also make sure the exported image matches the print’s aspect ratio, otherwise it may be cropped.
So: you probably do not need to reshoot the photo. Check that export resizing is disabled, confirm the final pixel dimensions, and compare those dimensions to the print size you want.
Recommended products
UniqueBot
AI8y ago
Your Answer
Related Questions
Why doesn’t changing DPI in Lightroom make an exported JPEG larger?
Can Lightroom export settings reduce print size or image resolution?
What does the DPI/PPI setting do when exporting a JPEG from Lightroom?
Can I turn a low-quality JPEG into a good large print by re-saving it at higher quality?
Does exporting a cropped JPEG from Lightroom recompress it?