Printing Confusion

First off, I rarely print images but I am going to make a photo book and am confused.

Example...a file that has been cropped to 4:5 ratio to print a 16 X 20 print. The file size is 4560 x 3648

If I export as .jpeg it comes out 5.8 MB

If I export as a .png the same file is 20.3 MB

Seems the .png would be the better choice for printing, no? But I don't understand why. I've searched around the internet only to get more confused by the minute!

Any help on this would be appreciated.

i-G12

this info may answer your question.

https://www.adobe.com …mparison/jpeg-vs-png.html

Quint on Trask wrote in post #19428810
i-G12

this info may answer your question.

https://www.adobe.com …mparison/jpeg-vs-png.html

But this it what confuses me…

If the dng has more info thst wasn’t thrown away like jpeg then this is what confuses me.

Contact the printer ... should give all info you need.

A 5.8 MB jpg should be more than adequate for a photobook. I usually save my work as TIFF files and do not use PNG. I print my own up to 17" wide and usually try to use the TIFF when printing the larger images. I read that PNG files were used to replace GIF files and since they are smaller that TIFFs they are better suited for web sites. I just compared the same image as a jpg and png on my screen and couldn't tell the difference. Too many choices out there.

Quint on Trask wrote in post #19428834
A 5.8 MB jpg should be more than adequate for a photobook. I usually save my work as TIFF files and do not use PNG. I print my own up to 17" wide and usually try to use the TIFF when printing the larger images. I read that PNG files were used to replace GIF files and since they are smaller that TIFFs they are better suited for web sites. I just compared the same image as a jpg and png on my screen and couldn't tell the difference. Too many choices out there.

Unfortunately the photo book maker doesn’t accept .tiff files for obvious reasons I guess — they’re generally huge.

My biggest issue is when cropping and ending up with a 1.5 MB file. Printing an 11 x 14 page that that size I wonder. I’ll give them a call but usually the service reps are relatively clueless about this technical stuff.

Is the resolution actually more important than the file size?

I just check a file just under 1.4 MB and at 218 pixels. Image size was 5 x7". I usually go to 300 pixels. At 11 x14 it looked very good also. I would print it with little reservation.
As long as I have over a MB I get a decent image.

Quint on Trask wrote in post #19428858
I just check a file just under 1.4 MB and at 218 pixels. Image size was 5 x7". I usually go to 300 pixels. At 11 x14 it looked very good also. I would print it with little reservation.
As long as I have over a MB I get a decent image.

Maybe I’m stressing over nothing.

The amount of space that a given photo occupies on disk (MBytes) in a JPG file is dependent upon the level of compression of data during output of the JPG file...the number of pixels in the photo is unchanged for Quality 2 vs Quality 9. It is the pixel count which matters, not the file size.

1. A photo with Low Quality JPG can occupy a lot less disk than a High Quality JPG photo, both with identical number of pixels.
   
2. But a photo with a lot of sky might be more tightly compressed with JPG Quality = Low (Quality =1) and the sky might be perceived as 'banding' due to high compression, than the same photo lightly compressed (Quality = 9),. If you output a JPG with Quality = 8 or 9, you will not get compression artifacts introduced into the resulting JPG file
   

Wilt wrote in post #19428895
The amount of space that a given photo occupies on disk (MBytes) in a JPG file is dependent upon the level of compression of data during output of the JPG file...the number of pixels in the photo is unchanged for Quality 2 vs Quality 9. It is the pixel count which matters, not the file size.

1. A photo with Low Quality JPG can occupy a lot less disk than a High Quality JPG photo, both with identical number of pixels.
   
2. But a photo with a lot of sky might be more tightly compressed with JPG Quality = Low (Quality =1) and the sky might be perceived as 'banding' due to high compression, than the same photo lightly compressed (Quality = 9),. If you output a JPG with Quality = 8 or 9, you will not get compression artifacts introduced into the resulting JPG file
   

Depending upon the quality of the offset press reproduction of a book, you only need 300 pixels per inch of printed photo size in the book. Any more is wasted resolution that cannot be reproduced by an offset press!

I was actually waiting for to you chime in @Wilt.

So a .jpeg in my example is just as good as a .dng for printing purposes is what I’m hearing. Yes?

Most commercial printers cannot handle RAW files ! and a DNG is simply a 'generalized' RAW file (not unique to specific camera vendor format).

Most commercial printers cannot print aRGB files... they accept only sRGB files, or they first convert aRGB to sRGB (which loses the colors that appear in aRGB but cannot appear in sRGB) before making the print.

Wilt wrote in post #19428911
Most commercial printers cannot handle RAW files ! and a DNG is simply a 'generalized' RAW file (not unique to specific camera vendor format).

Ooops. I meant .png.

i-G12 wrote in post #19428678
First off, I rarely print images but I am going to make a photo book and am confused.

Example...a file that has been cropped to 4:5 ratio to print a 16 X 20 print. The file size is 4560 x 3648

If I export as .jpeg it comes out 5.8 MB

If I export as a .png the same file is 20.3 MB

Seems the .png would be the better choice for printing, no? But I don't understand why. I've searched around the internet only to get more confused by the minute!

Any help on this would be appreciated.

PNG uses a lossless compression scheme and is better for raster images that contain sharp transitions (with text edges, etc) and large areas of uniform tone/color. JPEG compression is lossy but more suited to compress photographic images that contain areas of gradual tonal changes/gradients. Typically, when you save a photographic image as a JPEG and a PNG, the PNG file will be larger - the quality difference between the resulting files is typically not noticeable.

JPEG is fine for distributing photographic images, its intended purpose. It is not a terrific master file format intended for further editing. It also will suffer from generational loss, meaning that each subsequent open-save-close operation applied to the original JPEG will slightly degrade the quality - how many save operations will be required to produce noticeable loss will probably vary depending upon the image itself and the level of compression chosen in each save iteration.

Some online printing companies will specify a limit to the file size you can upload to have printed - you can control this file size by choosing a lower quality (more compreession) setting when saving the JPEG for the print house. Ideally, you do not want to have to crush the file with compression, and usually a Photoshop equivalent compression level of 8 to 10 (on a scale of 0-12) is a good balance of quality to size.

Kirk

kirkt wrote in post #19429603
PNG uses a lossless compression scheme and is better for raster images that contain sharp transitions (with text edges, etc) and large areas of uniform tone/color. JPEG compression is lossy but more suited to compress photographic images that contain areas of gradual tonal changes/gradients. Typically, when you save a photographic image as a JPEG and a PNG, the PNG file will be larger - the quality difference between the resulting files is typically not noticeable.

JPEG is fine for distributing photographic images, its intended purpose. It is not a terrific master file format intended for further editing. It also will suffer from generational loss, meaning that each subsequent open-close-save operation applied to the original JPEG will slightly degrade the quality - how many save operations will be required to produce noticeable loss will probably vary depending upon the image itself and the level of compression chosen in each save iteration.

Some online printing companies will specify a limit to the file size you can upload to have printed - you can control this file size by choosing a lower quality (more compreession) setting when saving the JPEG for the print house. Ideally, you do not want to have to crush the file with compression, and usually a Photoshop equivalent compression level of 8 to 10 (on a scale of 0-12) is a good balance of quality to size.

Kirk

Thanks Kirk.

In the end I'm probably OK to just use full size .jpeg's.

Appreciate the insight!