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tom mars
2006-03-28, 09:59 AM
Hi
I wonder about some things with images:


Why do scanned images never come in the right size?

Revit seems to ignore the dpi setting in the file, which is unnecessary.

What is the internal scaling factor in Revit?

Why cant they be rotated?

A reload file option would also be greatly appreciated...

blads
2006-03-28, 12:12 PM
Hi
I wonder about some things with images:


Why do scanned images never come in the right size?

Revit seems to ignore the dpi setting in the file, which is unnecessary.

What is the internal scaling factor in Revit?

Why cant they be rotated?

A reload file option would also be greatly appreciated...G'day Tom,

I can't help a lot but imported images can be definitely be rotated/flipped.With the imported image selected, click Flip/Rotate from the Options Bar to access flip and rotation commands from the Flip/Rotate Image dialog box.

Well its a start at least...

tom mars
2006-03-28, 02:38 PM
good day too,

thanks, i never clicked the button flip rotate becaus the standard rotate button
works but leaves no result.
so this means images can only be rotated by 90 deg:?
Now why is that?


What i forgot to mention in the previous post:

a crop option would be nice too!

Dimitri Harvalias
2006-03-28, 05:21 PM
Hi
I wonder about some things with images:


1 Why do scanned images never come in the right size?

2 Revit seems to ignore the dpi setting in the file, which is unnecessary.

3 What is the internal scaling factor in Revit?

4 Why cant they be rotated?

5 A reload file option would also be greatly appreciated...
1 What is the correct size for a scanned image? Images are brought into Revit according to the view scale. So at 1:100 an image that is 1200x600 pixels will be imported at twice the size at 1:200.

2 Not sure what you mean here

3 Didn't do the math here but I'm sure there is a 'standard' relationship between the image size and how it is brought into Revit

4 Image manipulation/control is far more flexible in R9. (not sure if NDA police will shoot me if I say more) Be patient, it's only going to be another few of weeks before R9 is out.

5 Couldn't agree more. A little right click funstionality here would be nice. At least give us the option of linking images as well as importing. To speed the process you can select the image and then use the create similar button on the options bar to get you to the original path of the image.

sbrown
2006-03-29, 02:24 PM
If you set your scale in your view, to the scale of the image, then know the size of the image(real paper size), just pick on the image and under its properties input the proper size. Ie, if you did a sketch at 1/4" on an 8.5 x11 sheet of paper, scanned it, then want it in revit to scale. Just create the view you want it in, set the scale to 1/4", import, then change the width of the image to 8.5"

If you have photoshop you can open the image there and find out its size there.

rhuserik.96436
2011-05-19, 09:46 AM
It is a bit disappointing to see that even in Revit 2011 (five years after this thread began) you still cannot do a simple operation like reloading an image.... or for that mater crop an image. Even basic programs such as power point include such functionality.

patricks
2011-05-23, 02:21 PM
Revit wasn't designed with raster image handling in mind, which I believe to be the reason for the rudimentary tools available to handle them.

Need to crop an image? Put it in a modeling view and use the crop region. Or put it in a drafting view with a masking region.

As for the size, a raster image comes in sized per 72 DPI. Why 72 DPI? I have no clue as that was a standard originated by Macintosh in the 1980's (Microsoft's standard was 96 DPI). However, the pixel count of the image is maintained. If you divide your image's pixel dimensions by 72, and then further divide by your view scale, you'll see that the image's dimension properties match your calc's.

I do know one thing, it is better to size an image smaller in Revit than in a photo editing program. You can resize the image smaller in Revit and pixel count and information is maintained, whereas if you resize smaller in an image editor, pixel info is lost. And if you simultaneously reduce image size and incease DPI in Photoshop to maintain the same pixel count, the image will come into Revit the same size as before, anyway.