11-13-2020, 11:50 PM (This post was last modified: 11-14-2020, 12:28 AM by Mark-Gim.)
My friend sent me an image saved as a .pdf file made in Photoshop.
I loaded the image into GIMP and made a very small change to the image.
I would like to save the file once again as a .pdf file and NOT LOSE ANY image quality.
The file sent to me was approx. 4M. When I save the file in GIMP the file size becomes approx. 312K, or less than 1/10 the size of the original file. When I look at the two images, the GIMP image has lost quality.
Can someone please tell me how I can do this? Thanks!
....
More info.
I also have the same image file as a .tiff file (coming from Photoshop).
When I open the file in GIMP and edit it (small edit) I can save it as a .tiff
and the file size remains the same! Approx. 4M.
But, when I try to save it as a .pdf file, the file size becomes approx. 312K !
How did my friend save it in Photoshop as a 4M .pdf file,
and how can I save it in GIMP as a 4M .pdf file?
(11-13-2020, 11:50 PM)Mark-Gim Wrote: My friend sent me an image saved as a .pdf file made in Photoshop.
I loaded the image into GIMP and made a very small change to the image.
I would like to save the file once again as a .pdf file and NOT LOSE ANY image quality.
The file sent to me was approx. 4M. When I save the file in GIMP the file size becomes approx. 312K, or less than 1/10 the size of the original file. When I look at the two images, the GIMP image has lost quality.
Can someone please tell me how I can do this? Thanks!
....
More info.
I also have the same image file as a .tiff file (coming from Photoshop).
When I open the file in GIMP and edit it (small edit) I can save it as a .tiff
and the file size remains the same! Approx. 4M.
But, when I try to save it as a .pdf file, the file size becomes approx. 312K !
How did my friend save it in Photoshop as a 4M .pdf file,
and how can I save it in GIMP as a 4M .pdf file?
Okay, I am no expert but TIFF is an uncompressed bitmap format. If you are using the File | Export As option in GIMP to get the PDF, one of the default selections is to convert bitmaps for vectors. Have you tried unchecking that?
(11-14-2020, 01:46 AM)eepjr24 Wrote: Okay, I am no expert but TIFF is an uncompressed bitmap format. If you are using the File | Export As option in GIMP to get the PDF, one of the default selections is to convert bitmaps for vectors. Have you tried unchecking that?
- E
Yes I tried unchecking that box.
I also tried unchecking:
-Apply layer mask
-Omit hidden layer
but it didn't help.
In all cases the file size became around 300K.
I would like to save the file if possible in as high a resolution
as possible in .pdf form.
As I mentioned, the .tif file saves at around 4M,
but the .pdf file saves at around 300K.
Somehow Photoshop managed to save in each format at around 4M.
11-14-2020, 10:08 AM (This post was last modified: 11-14-2020, 10:14 AM by rich2005.
Edit Reason: edit
)
Quote:...But, when I try to save it as a .pdf file, the file size becomes approx. 312K ! How did my friend save it in Photoshop as a 4M .pdf file, and how can I save it in GIMP as a 4M .pdf file?
Too late, go back and start again.
A PDF from PS might contain raster images (images made up of pixels) as well as embedded text and maybe vector objects (arrows, stars..etc) These open in a PDF viewer and can be viewed in good quality from small to large size.
Gimp is a raster editor. Open the PDF in Gimp and everything is converted to a single image made up of pixels. Text is also converted to raster, this does result in loss of quality when viewed at high 'zoom'
By default Gimp will import the PDF with a resolution of 100 pixels-per-inch (ppi). Not only Gimp other applications do the same.
This has a big influence on quality. Assuming your PS PDF contains a photographic quality image then import the PDF with a ppi of 300. Settings like this:
If you are using Gimp 2.10.22 and added text, it seems to add the text metrics correctly. Earlier 2.10 versions, not so good, flatten the text before exporting.
Export settings ? For a single page it does not make much difference. I leave everything checked. I have never seen Gimp convert a bitmap to a vector. Gimp 2.10 Multi-Page is a disaster, text layers export to separate layers, avoid.
File size ? All depends what that PS PDF contains. They do seem to be large and Gimp might be smaller, as long as you remember the Gimp PDF is now a single bitmap image.
EDIT Just seen Windows XP and Gimp 2.8 - All as above except text is automatically flattened and there is no mult-page option anyway.
Quote:...But, when I try to save it as a .pdf file, the file size becomes approx. 312K ! How did my friend save it in Photoshop as a 4M .pdf file, and how can I save it in GIMP as a 4M .pdf file?
Too late, go back and start again.
A PDF from PS might contain raster images (images made up of pixels) as well as embedded text and maybe vector objects (arrows, stars..etc) These open in a PDF viewer and can be viewed in good quality from small to large size...
If you are using Gimp 2.10.22 and added text, it seems to add the text metrics correctly. Earlier 2.10 versions, not so good, flatten the text before exporting.
Export settings ? For a single page it does not make much difference. I leave everything checked. I have never seen Gimp convert a bitmap to a vector. Gimp 2.10 Multi-Page is a disaster, text layers export to separate layers, avoid.
File size ? All depends what that PS PDF contains. They do seem to be large and Gimp might be smaller, as long as you remember the Gimp PDF is now a single bitmap image.
EDIT Just seen Windows XP and Gimp 2.8 - All as above except text is automatically flattened and there is no mult-page option anyway.
Thanks for helping out Rich!
Everything you say sounds fair enough re: importing the .pdf into GIMP, making
small change and then exporting as .pdf.
But how about the other option I tried?
Importing the .tif from PS, making a small change
and then exporting as a .pdf?
Does GIMP actually change the rasters into vectors?
And why does the file size go from 4M to 300K
(.tif to .pdf) when PS maintains the same file size?
11-14-2020, 07:27 PM (This post was last modified: 11-15-2020, 08:31 AM by rich2005.
Edit Reason: edit
)
Quote:Does GIMP actually change the rasters into vectors?
I have never found that Gimp converts rasters to vectors. Giving Gimp the best chance in the world, simple shapes each on its own layer. A small difference in file size. (1) Usually, single layer, no difference. As a comparison a PDF from Inkscape (vector editor) same size / layout is 1.2 K vs. Gimp 60 K
Quote:And why does the file size go from 4M to 300K (.tif to .pdf) when PS maintains the same file size?
Tiff format comes in various forms, uncompressed, lossless compressed.. file size can vary considerably.
The example shown, all the same image, (2) jpeg 400K / (3) compressed tiff 4.5M / (4) uncompressed tiff 10.5M Once opened in Gimp there is no format just pixels.
Exported as a PDF the only real difference is jpeg v. tiff but in all cases the PDF is not tiny. There will be some compression by Gimp (probably RLE).
Just a guess, I think that PS is just 'bundling' up whatever the file is, large file size or small in a PDF 'wrapper' . You can get that with say, ImageMagick
No idea why your tiff file should shrink so dramatically, does it contain large expanse of solid colour that compresses a lot? Are the tiffs 16 bit images down to 8 bit in the PDF. Too many unknowns.
edit: Just a thought. A tif file can contain a thumbnail image. That would show opening in Gimp as two pages, make sure you use the correct one (page 2 ?). It should be obvious from the image size shown top of the Gimp window.
(11-14-2020, 07:27 PM)rich2005 Wrote: ... No idea why your tiff file should shrink so dramatically, does it contain large expanse of solid colour that compresses a lot? Are the tiffs 16 bit images down to 8 bit in the PDF. Too many unknowns.
edit: Just a thought. A tif file can contain a thumbnail image. That would show opening in Gimp as two pages, make sure you use the correct one (page 2 ?). It should be obvious from the image size shown top of the Gimp window.
Hi Rich thanks for helping out again!
I would like to nail this one down.
I will fill in more details that I have learned.
I would like to understand everything as best as possible.
I'll start by saying where I am and where I'd like to get to.
I have two transparent background files sent to me by my friend that were made in PS.
One is 4.3M and at 900x1200 pix.
The other is 4.5M and at 2700x3600 pix.
For some reason the 4.5M file will not show when I try to view it in my file viewer ( but I can load it into GIMP).
I have edited my friends files and they are good to go in GIMP.
I have made a few transparent background versions:
2700x3600 trans.png 1.7M
900x1200 trans.png 393k
900x1200 trans.pdf 312k (shows with white background in viewer)
900x1200 trans.tiff 4.3M
2700x3600 trans.tiff 2.1M (compressed at 9)
2700x3600 trans.tiff 38.8M (no compression)
I would like to get the best possible resolution file that I can make available for download on a site
so people can use it to print t-shirts and other wares.
I had thought that a .tiff file would be best suited for this.
I also understand that .pdf's are a preferred file type because it's a vector file.
I'm at a loss now as to what direction I should go with?
Strangely, my website refuses to allow .tiffs to be downloaded (all other types allowed).
Quote:...I have two transparent background files sent to me by my friend that were made in PS. One is 4.3M and at 900x1200 pix. The other is 4.5M and at 2700x3600 pix.
The image size is no real indicator of file size. I have a PS psd template that is 2400 x 1700 pix with a file size of 28 MB but it also has 21 layers, some with a mask, each adding to the file size.
Quote:...I would like to get the best possible resolution file that I can make available for download on a site
so people can use it to print t-shirts and other wares...
Your intent is files for printing on goods. Tee-shirts, coffee cups maybe. You need to consider the image content.
Photographs use jpeg. This is a lossy 'final' format with good compression, does not support transparency. Work in Gimp xcf until that final 'export'. You can also use png as a final format. Png has lossless compression, it does support transparency (alpha channel adds to the image size)
Logos, bold designs etc. You can use png for these although truthfully logos are best made as vector images with Inkscape.
Using tiff, this format is really a wrapper, more variations than enough, from fax images to scientific imaging. It has some use in Gimp in conjunction with the DP program Scribus. Probably not the best format for your intended use.
Quote:...I have made a few transparent background versions: 900x1200 trans.png 393k
900x1200 trans.pdf 312k (shows with white background in viewer)
A PDF does not support transparency. As the name says, Portable Document. Think printed on paper.
Which leads to the printing process. There is no white ink. The printer uses primary colours Cyan, Magenta, Yellow + Black. White is whatever the colour of the paper / fabric / ceramic. When white is required in the image it is has to be specified, then becomes a custom job for the printing company and (much) more expensive.
Quote:...I also understand that .pdf's are a preferred file type because it's a vector file..
Not really true. Only for logos and simple designs, and these are best made with Inkscape or other vector editor, Even these can contain a raster image or a mix. This example, https://i.imgur.com/bB8tCOl.jpg two pdf's basically the same logo, All vector in inkscape, all raster from Gimp. For printing at the set size, 4" x 4" no difference in quality, big difference in file size. Start changing the size then a vector image (scaleable .svg or PS .ai) is preferable.
If you are going to send your images off for printing on a tee-shirt, then find out the size requirements. A maximum size of say, 12" gives you an image size in Gimp of 12 X 12 (inches) x 300 pixels-per-inch (ppi) = 3600 pix x 3600 pix.
A coffee cup might be 3" x 6" @ 300 ppi = 900 pix x 1800 pix. No good sending the same image for both.
Image format: Back to jpeg for photographs and png for others. PDF if you must.
Thanks Rich your reply is really helpful.
I think I am getting very close now to deciding on the best file format for my situation.
Just one more question.
Quote:...I would like to get the best possible resolution file that I can make available for download on a site
so people can use it to print t-shirts and other wares...
"Logos, bold designs etc. You can use png for these although truthfully logos are best made as vector images with Inkscape."
At this stage, I will stick to GIMP as I don't have the time nor skills to use a new program such as Inkscape.
"Using tiff, this format is really a wrapper, more variations than enough, from fax images to scientific imaging. It has some use in Gimp in conjunction with the DP program Scribus. Probably not the best format for your intended use."
OK this is good to know!
Quote:...I have made a few transparent background versions: 900x1200 trans.png 393k
900x1200 trans.pdf 312k (shows with white background in viewer)
"A PDF does not support transparency. As the name says, Portable Document. Think printed on paper.
Which leads to the printing process. There is no white ink. The printer uses primary colours Cyan, Magenta, Yellow + Black. White is whatever the colour of the paper / fabric / ceramic. When white is required in the image it is has to be specified, then becomes a custom job for the printing company and (much) more expensive."
OK this is very helpful!
Transparency is a must for t-shirt printing, to eliminate white background and also other white spots.
GIMP takes care of this nicely.
"If you are going to send your images off for printing on a tee-shirt, then find out the size requirements. A maximum size of say, 12" gives you an image size in Gimp of 12 X 12 (inches) x 300 pixels-per-inch (ppi) = 3600 pix x 3600 pix.
A coffee cup might be 3" x 6" @ 300 ppi = 900 pix x 1800 pix. No good sending the same image for both.
Image format: Back to jpeg for photographs and png for others. PDF if you must."
It sounds like for my situation .png will be the best way to go.
To cover situations where users will download the file to use on an assortment of wares
in addition to t-shirts, would it make sense to come up with the highest resolution file (also large)
and let them downsize the file for smaller print jobs, or offer a few different .png file sizes to download?
It seems like you were advising the latter?
A couple more questions:
A site that gives instructions for making t-shirts advises the following:
Be at least 150 dpi
Use CMYK colour mode
Have a transparent background
Have no effects like ‘Drop Shadow’ or ‘Glow’
Have all types rasterized
Saved as either EPS, PDF, PSD or PNG
It was my understanding from what Rich said that a .pdf file can't have a transparent background?
All of my .pdf files that were saved with transparent backgrounds show in viewers with a white background.
If they can't have a transparent background, why does this company recommend a trans. background AND
a .PDF file?
Also where do I go in GIMP to set the Type to be rasterized?
