Raw to JPEG shrinks my file size...what can I do?

Hmmmmm,

JPG files are always smaller than RAW files of the same resolution. If I were you I would focus more on the file resolution than file size. If you really want a big file that will make no difference in how the print looks you can always export as a 16bit tiff or psd - that should be pretty "big"

RB

wpiacenti@mac.com wrote:
Here's the problem...while using aperture 2.0, i have RAW images, one in particular is 8.91MB in it's raw format. I make all of my adjustments, then i click Export Version (the version that i like). In the dialog box, I choose JPEG - Original size, and i save to desktop. When I look at the properties of the new JPEG file, it's only 3.5 MB which is too small for my 16x20 enlargement that I want to make of my son for his first christmas on santa's lap. Please help if you can. Thank you much in advance!

The short answer is that JPEG is a "lossy" format, meaning that image information is lost with each successive save into JPEG. If possible JPEG should be avoided in the workflow when images may be used for print. Save instead to a lossless format like TIFF or PSD, ideally 16-bit.

The long answer is that even though JPEG is a "lossy" format, JPEG has a quality range from 1 through 12 and there is a huge difference from JPEG-1 to JPEG-12. One single save into JPEG at maximum JPEG quality (12) usually will not be visibly different in hard copy if the original image was well shot. OTOH images can be rendered pretty much illegible with a single save into low JPEG levels.

Bottom line for print is to avoid JPEG like the plague. If JPEG is unavoidable (such as from a low end camera, or when a pic is received already in JPEG format) immediately convert the image to a lossless format like TIFF or PSD before entering the image into a workflow. If JPEG is required for output, only convert to JPEG as the absolute last workflow step, and use the highest JPEG quality that the usage will tolerate.

-Allen Wicks

P.S. The observation above "if the original image was well shot" is critical. A poorly shot image may show JPEG artifacts with a single save into the JPEG format even at highest JPEG quality level. Best is simply to avoid JPEG when feasible.

It's only "too small" if you get pixelation at your target print size. As mentioned by the previous honorable posters, you're using a format that compresses the file size. Of course the file is going to be smaller than the raw original.

Whether the resulting print is sucky will be more dependent on the capability of the photographer, the post-processing, the printer and print settings used and the resolution of the original.

As a recent convert to shooting raw instead of jpg, the main differences have been no more jpg artifacts, much more latitude in white balance and exposure adjustments, and fewer sharpening artifacts. In both formats though, a well-taken photo is still a well-taken photo...

Regards,
Calx

Message was edited by: CalxOddity

Message was edited by: CalxOddity

that makes it 8 megapixels, or 10? I'm a Nikon D40 user, so can't count after 6... 😉 I'm supposed to be able to do a decent print to A3 size (around 11.5 x 16 inches, whatever they are), but haven't done one that big yet.

I seem to recall that if you achieve minimum 200 dpi the photo looks good. For a 16x20" photo that means the minimum resolution of the photo should be 3200 x 4000 pixels - ie something over 12 megapixels. Notice there's no reference point for file size...

Anyhow, the proof of this pudding is in the printing. Good luck! If all else fails, reducing the print size may work out for you.

Regards,
Calx

The size of a JPEG version, if Original Size is used, differences only in the size of the file after it compressed into JPEG. If you look at the pixel dimensions they will be the same. When the JPEG is decompressed the file size will be the same as, say, a TIFF or .psd without compression. None of them will have the same file size as the RAW -- typically any of my TIFF or PSD versions are actually a bigger file than the RAW original because my Nikon saves a compressed RAW.

If you don't do any editing and another save, a JPEG will be a fairly faithful version of the original. Any detail that might be lost, if any, would not be due to file size, but to the loss of detail during compression.

Ernie

wpiacenti@mac.com wrote:
...I'm only worried that the photo (a really well taken photo in my opinion, shot with a rebel xti and canon 80mm 1.2L) will not look good when it is blown up to a 16x20" poster-size print when the file size is now only 3.5MB. I will upload to my print center and see how it goes.

Your well-shot print from that lens should look fine if the printer is otherwise competent. Key is to make one save to JPEG as the very last step prior to sending to the printer. And do not make any adjustments to actual pixel dimensions to achieve some arbitrary ppi.

Good luck!

-Allen Wicks

wpiacenti@mac.com wrote:
I'm only worried that the photo (a really well taken photo in my opinion, shot with a rebel xti and canon 80mm 1.2L) will not look good when it is blown up to a 16x20" poster-size print when the file size is now only 3.5MB.

The file size does not matter at all. A photo with a lot of blue sky, for example, can be compressed to a much smaller size than a photo with a lot of details of, for example, a building or a portrait.