it comes with 1024px x 768 px at 100% ! But the Links panel says that the size of this image is 2048x1536
I think you are confusing image resolution with print output dimensions. If you click on an image or frame and open the Transform panel you will see its print output dimensions in the Width and Height fields. InDesign allows you to choose pixels as a measurement unit, so for the purposes of print output a pixel measurement unit is given a dimension of 1/72". If you make a box that is 1"x1", its pixel dimensions will be 72x72 no matter what its content is.
So if you place 72ppi images at 100%, their print output dimensions as pixels will match their pixel dimensions. The print measurement system has nothing to do with pixel per inch image resolution.
If you want the frame dimension of your 150ppi image to match its pixels dimensions, you have to scale it to 208.33% (or (150/72)x100).
A document page set to 2048x1536
Hi Rob, thank you for your answer but the problem is not the resolution (I know this very well, I'm senior). The problem is that Indesign changes the image size when I import it. See below :
Here is the image size in Photoshop (CC 2015 too)
Here is the InDesign document size :
Now my image imported (just imported) as it is. You see that InDesign has resized the image from 2048 to 1024 (the single page width).
InDesign displays this informations :
I didn't have this problem with Indesign CC2014. I did the update to CC2015, and this thing appears… Thanks for your help
What you are seeing is correct. InDesign uses a 1:1 correspondence between pixels, which have no dimensions, and points, which are a unit of linear measurement, when you specify a pixel-sized document.
In Photoshop the saved resolution makes no difference because you are only concerned with pixel count, not how large or small those pixels will be rendered. When you put that image onto a page for output the page has a physical dimension, and the saved resolution in Photoshop defines a physical size for the output.
2048/150 = about 16.6533 inches. There are 72 pts per inch, so your 1024 width page is 1024/72 = about 14.222 inches wide. Your image is placed on the page at the ratio of 72/150, which in this case gives you frame dimension of 963.04 pts (or pixels in ID) wide, which is what is showing in the screen capture.
If you want a direct correspondence between the pixel dimensions in Photoshop and the physical size in ID, you should re-save the image at 72 ppi.
All of this is just another way of looking at what Rob said above.
Also keep in mind that the transform scale of a placed image is relative to print output and not the image's pixel dimensions—this is true even if you set the document up for a web or digital publishing intent. If you set your ruler units to inches in both Photoshop and InDesign, your 150ppi image at 100% has an output dimension of 13.653"x10.24".
Thank you for all these numbers. But my problem is very simple :
what size and resolution must I prepare in Photoshop for a epub 3 FXL read with Ibook on a IPad Retina
1. if I want my image in full size (background) in an orientation landscape ;
That's all… I think all folks will be very happy to know that clearly.
Thanks very very much
Save at 72 ppi....
I think you mean this tutorial: http://www.trainsimple.com/CourseDetailUser.aspx?id=188
There is also the Lynda.com tutorial: http://www.lynda.com/InDesign-tutorials/Creating-Fixed-Layout-EPUBs-InDesign-CC/169624-2.h tml?srchtrk=index:1%0Alinktypeid:2%0Aq:ann-maria%2Bconcepcion%0Apage:1%0As:relevance%0Asa: true%0Aproducttypeid:2
And there's a forum for InDesign ePub posts.