Importing a raster image sees result approx 4 times as big appear.

[Steve1]

Hi,

My first ever attempt to use AD and draw over a raster image.

Searched on import raster, found nothing, I see there is File>place so guessed that is it.

Raster image 300 pixels/inch  103.89mm wide

 

AD new document 400dpi  A4 portrait (210mm wide)

thus the raster should easily fit on the page, its half its width and also less than its dpi.

 

Go file>place and the result is twice as wide as the page ! as its only 103.89mm its in fact about 4 times as big as expected.

 

I have been using Macromedia Freehand this last 30 years and Rhino3D the last 10 or so years so I am familiar with importing rasters into vector progs.

Its name top left I see has @72dpi, so it has rescaled it to be 72dpi. Why has it done that ?

 

I need the images to be places at their true size. Now what is the fix please and how do I stop it ever doing that again ?

 

Cheers

Steve1

[R C-R]

Are you sure of the dimensions & ppi of the raster image file? 300 pixels/inch is about 11.8 pixels per mm, so your raster image file should be about 1227 pixels wide. Is that its width in pixels when checked with another app or utility that shows its pixel dimensions?

 

The Place Image Tool will use the image file's default dimensions (calculated from its embedded pixel dimensional metadata) if you click on the canvas without dragging to place it. That is what you should see on the left in the Context toolbar. If there is insufficient embedded dimensional metadata Affinity will use a default DPI value -- I think it is 96 dpi but I am not sure of that.

 

Note that the embedded pixel dimensional metadata is stored in different ways for different file types, so for example a PNG file will include a "pixelsPerUnitXAxis," a "pixelsPerUnitYAxis," & a "unitSpecifier" value. The unitSpecifier can have a value of "meter" or "unknown." If it is "meter" then a dpi value can be calculated from these values; if it is "unknown" then the dpi value is undefined.

 

You did not say which version of Affinity Designer you are using. I am using version 1.5.5 for Mac. When I use the Place Image tool in this way (without dragging to set custom dimensions) with an image file I know has sufficient metadata to determine a 300 dpi value, the dpi value shown in the Context toolbar is "@ 300dpi." For 72 dpi files it is "@ 72dpi" & so on. If you are using Windows, something different may be happening.

[Steve1]

Hi,

AD 1.5.3.69 for PC

 

Quote

Are you sure of the dimensions & ppi of the raster image file? 300 pixels/inch is about 11.8 pixels per mm, so your raster image file should be about 1227 pixels wide

Open it into photoshop, its 1227pxels wide.

Doing now a test, create new AD page A4 size 300 dpi. see image.

create a new jpg in photoshop 300 dpi 105mm x 148.5mm which is half width and height of this page, thus it is A6. both image and page are at 300dpi,

go file>place and bring in the image, it should occupy quarter of the page, instead its twice as big.

I have been doing such raster imports using files (jpg and tiff) created in photoshop since win 95 and know this territory like the back of my hand, never before has this ever occurred in a program.

AD has a fundamental flaw here. top left it declares image as 72dpi. Its altering its resolution.

 

second test, create and save the A6 image as a tif, not a jpg, place into AD and its the correct size !

AD is failing to understand the resolution of a photoshop jpg !!!!!  AS pshop jpgs work fine in CAD and Freehand, its AD at fault.

Can someone else test this, do this test with photoshop and AD.

I have seen Rhino3D in print option do such, when user creates a 300dpi raster print and importing it into photoshop sees it becomes 72dpi. A gremlin there.

I cant even start to use AD as jpg images are not correct size.

DBenz

 

 

 

[R C-R]

All I can tell you is that I cannot duplicate this on my Mac. I have tried with a variety of jpeg, tiff, & other image files. If they include embedded DPI metadata (or the equivalent), clicking without dragging using the Place Tool drops them into the document at that DPI.

 

Would it be possible to attach a sample of a 300 DPI jpeg, tiff, or similar image file that produces this problem for you?

[toltec]

72 ppi is just a standard for computers and screen images. Designer wont be altering the resolution, just the way it is sized on the document.

 

It assumes the screen is 72 pixels per inch so tries to make 1227 pixels occupy 17 inches. If the dpi is set in the file, it should read that and size it accordingly. I don't know why not. 

I don't have Designer but tried Photo. At 72 dpi  1227 pixels is 103.886 mm  Which Photo got right when I tried importing a 1227 px image. As it appears, so did Designer, at least the way it described it.

 

And what a mixture of sizes and measurements. Dots, per inch, pixels per inch and 105 millimetres. 300dpi images in a 400dpi document. Why 400?

If Designer read the dpi in the image, 300 dpi would be the wrong size,at in a 400 dpi document. So if you "need the images to be places at their true size" it wouldn't work anyway.

 

Just go to the Transform panel and set the image to 105 mm or 103.886 (which is the true size) the dimensions displayed will change accordingly.

[Steve1]

Hi,

file attached.

 

all I know is in 20yrs or more since win95, I have never had this problem occurring, certianly though since XP, I seem to recall in 95 days maybe freehand not handling jpg, I was an tifff user, no probs, but since win2k or certainly xp, I have been placing jpg into Freehand, and CAD, be that Rhino, or a few others, no expanding jpegs. Designer shouldnt do this.

 

its a 300dpi jpg placed into a 300dpi a4 document and it should be at its created size of A6. ...simples...squeeek !

I work to loads of rasters and need them to stay at their size they were created at.

DBenz

[R C-R]

@Steve1 Please attach a TIFF sample file to your post. I don't know if the attachment in your previous post is representative of the files you normally work with, a screenshot, or has been mangled by the upload to the forum but it has a very long file name ("597fb39e86a17_105mmx148300dpi.jpg.f18598a73bdf0ed2f6f8cddaafec490e.jpg") that suggests it may not be representative of those files.

[MikeW]

Yep, the image you attached comes in at 72 dpi and is sized accordingly.

 

I opened that image in PS and did a simple Save As.

I opened that image in Photoline and did a simple Save As.

 

Both came in with AD respecting the DPI and were sized accordingly.

 

 

So I don't know if the attached is mucked-up like R C-R may suspect (forum software can alter an image) or whether it is a fault of the creation/save path.

 

I would recommend Zipping a test image so there's no chance of the upload process altering it.

 

Mike

[MikeW]

Oops. Attached is a ZIP file of both of my resaves for your own test.

 

Mike

 

Desktop.zip