The Overlay feature allows addendum drawings to overlay existing images making it easy to identify changes.
Additions appear in blue and deletions appear in red.
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Overlay images must be the exact same size and have the same scale as the original image. On-Screen Takeoff cannot edit or manipulate the size/scale of overlay images. If your images are not aligning, you will need to contact the Architect or provider for a properly scaled overlay image. You may also be able to edit the file outside of On-Screen Takeoff so that it overlays correctly. |
To select an Overlay Image
Right-click anywhere on the image and click Select Overlay Image -
Browse to the addendum drawing, select the file, and click 
.
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Overlays cannot be an indexed (multipage) file. They must be single page files in order to display correctly. (An example of an indexed file is a single PDF file that contains multiple pages - in this case, only Page 1 can be displayed as an Overlay. You can use Adobe Reader to extract the individual pages, if necessary). |
The addendum drawing is overlayed on top of the original image.
Aligning your Overlay and Original images
The addendum may not line up exactly with the original when it is first selected. To align the overlay drawing to the original, right-click anywhere on the image and click Overlay>Align Overlay Image.A line with green circles at either end is displayed - this is the alignment tool.
The move handle 
moves the overlay image up-down and side-to-side. The arrow keys on your keyboard can nudge the overlay image if the alignment is only slightly off.
The rotate handle 
spins your overlay image along the center axis.
Once the images are aligned, deletions are shown in red and additions in blue.Adjust your takeoff as needed to account for the changes in the Overlay.
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When you zoom in very closely, you may see less grey - this is expected. Every page is slightly different if you zoom in very closely. On-Screen Takeoff compares the two images and will show you, down to the pixel if you zoom in that close, what is different. The Overlay feature is designed to allow you to see what has changed, overall, on a plan. |
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Page rotation and takeoff alignment is based on the original or base image. Selecting to display ONLY the Overlay, may cause takeoff to rotate out of alignment with the image. Turning the Original image back on will correct the display. |
Converting Overlay PDFs to TIFF