Revit and Camera Match / FOV and Focal Length

[Munkholm]

Inspired by a wish in the Wish List sub-forum, I´ve created the attached family to make Camera Matching easier in Revit:

(Make sure to measure your location when shooting the photo to be matched)

• Place the the family in the project, at the same location and direction as you real photo.
• Change the "Camera Height" and "Target Height" in the family to match your real photo (Instance parameters).
• Make sure the "Focal Length" is set to 23.7 mm (Instance Parameter), which apparently is the equalliant of the standard Revit Camera.
• Take note of the "Target Width" in the family, i.e. 4683 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Take note of the "Target Height" in the family, i.e. 3122 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Place a Revit Camera on top of the Family, with the same direction and length.
• Go to the Camera view and change the Crop Size width to 4683 mm (Target Width) - Make sure to check "Scale (Locked Proportions)"
• Now change the Crop Size Height to 3122 (Target Height) - Make sure to check "Field of View"

You should now have a Revit Camera that matches the Family, but to make it all fit the actual photo:

• Open the photo, and in the properties take note of the Focal Length, i.e. 18 mm if you used a wide angle lense.
• In the family, change the "Focal Length" to match the photo properties, i.e. 18 mm
• Take a new note of the changed "Target Width" and "Target Height" (6167 mm and 4111 mm if you followed the above examples)
• In the camera view, change the Crop Size to match the above - Make sure to check "Field of View"

Your camera view should now be a pretty exact match of the photo!

Disclaimer:
The attached family is based on the physics of a Canon EOS 1000D, and is being calculated based on the formulas at Wikipedia - Use at own risk.

[MB78]

Thank you so much Munkolm! your family is a blessing, post of the month for sure. If I have understood properly the formulas, they are all driven by the dimensions of the camera sensor, right? just for using it with my old nikon..

thanks again
bye
MB

[Munkholm]

You are welcome - and welcome to the forum too

And yes, if you know a little about your camera, you should be able to adjust the size of the sensor in the family.

Usually the camera specs. also include minimum and maximum Angle of View with minimum and maximum Focal Length with the standard objective - Use that to make sure that the family is doing the right calculations for your camera.

[dzatto]

How do you come up with this stuff?? Greatness. :thumbsup:

[niku]

How do you come up with this stuff?? Greatness. :thumbsup:

Hi,

Torsten posted some basics 3 years ago @cad.de

http://ww3.cad.de/foren/ubb/Forum329/HTML/000908.shtml#000009

Suerte y gracias Klaus

[philopep]

Revit 2012 camera questions

I would like to be able to match an existing photo using Revit 2012. I downloaded the cannon family in the post and loaded it into the drawing using the "load into project" option after opening the camera file in 2012.

The only place I can find where I can load a camer is under view, 3d view and then camera. It allows me to load a camera but I cannot find how to specify what the camera type or how to specify the cannon camera family.

Thanks

Inspired by a wish in the Wish List sub-forum, I´ve created the attached family to make Camera Matching easier in Revit:

(Make sure to measure your location when shooting the photo to be matched)

• Place the the family in the project, at the same location and direction as you real photo.
• Change the "Camera Height" and "Target Height" in the family to match your real photo (Instance parameters).
• Make sure the "Focal Length" is set to 23.7 mm (Instance Parameter), which apparently is the equalliant of the standard Revit Camera.
• Take note of the "Target Width" in the family, i.e. 4683 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Take note of the "Target Height" in the family, i.e. 3122 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Place a Revit Camera on top of the Family, with the same direction and length.
• Go to the Camera view and change the Crop Size width to 4683 mm (Target Width) - Make sure to check "Scale (Locked Proportions)"
• Now change the Crop Size Height to 3122 (Target Height) - Make sure to check "Field of View"

You should now have a Revit Camera that matches the Family, but to make it all fit the actual photo:

• Open the photo, and in the properties take note of the Focal Length, i.e. 18 mm if you used a wide angle lense.
• In the family, change the "Focal Length" to match the photo properties, i.e. 18 mm
• Take a new note of the changed "Target Width" and "Target Height" (6167 mm and 4111 mm if you followed the above examples)
• In the camera view, change the Crop Size to match the above - Make sure to check "Field of View"

Your camera view should now be a pretty exact match of the photo!

Disclaimer:
The attached family is based on the physics of a Canon EOS 1000D, and is being calculated based on the formulas at Wikipedia - Use at own risk.

[mdradvies]

I would like to be able to match an existing photo using Revit 2012. I downloaded the cannon family in the post and loaded it into the drawing using the "load into project" option after opening the camera file in 2012.

The only place I can find where I can load a camer is under view, 3d view and then camera. It allows me to load a camera but I cannot find how to specify what the camera type or how to specify the cannon camera family.

Thanks

I'm afraid you're mixing to things up... The Camera FAMILY can be loaded and placed using the "Component" button in the Home Tab. THIS IS NOT THE ACTUAL VIEW!!! Place this in Plan View.
After placing the camera FAMILY, go to the View Tab, click on the drop-down arrow beneath 3D view and select camera. Now place the camera VIEW-icon directly on top of the camera FAMILY and modify the settings for both in order to match views.

[GMcDowellJr]

Alternate Family Version

I just found this thread (no idea how I got here now) and started playing with the family but it wasn't working the way I assumed it would so I dug into into and reworked it to make sense for our workflow and thought I'd share the results.

Basically, instead of entering values for the camera crop at the target point (which will produce a rather large image in terms of overall dimensions) it puts them in the range of what a default Revit camera uses (6"x4.5").

In case anybody tries to reverse engineer this I had to use a different focal length than Munkholm used to get things to work. This document from Pacific Alliance Technologies (http://forums.autodesk.com/autodesk/...t%20Camera.pdf) suggests a focal length of 38.6mm with a 50 degree horizontal field of view. Working backwards from those numbers I determined that the sensor size of the default Revit camera is 36mm x 27mm with a 60.5 degree diagonal field of view equivalent to a crop factor of .96

This works a bit differently than Munkholm's;

* Set Sensor Width/Height (type) from camera manufacturer's data in mm*
* Set Focal Length (instance) from lense manufacturer's data in mm*
* Transfer Crop Width/Height (instance) to the Revit camera's Model Crop Size fields with Field of View checked (later, if you need a bigger image, you can scale the crop)
* Other values, like Eye/Target Elevation (instance), can be changed as needed. These aren't critical to get the camera view correct but might be useful if you want to visualize camera locations in views.

(*These are number parameters. We work in imperial and seeing the inch version of metric is confusing.)

That's it... hope you find it useful and thanks to Munkholm for the original family/idea!

[zahrarasti]

Thanks for your post, but I have a question:
I have a real photo and need to adjust my camera in revit In exact place which real photo has been taken.
how can I do this?
Thanks

Inspired by a wish in the Wish List sub-forum, I´ve created the attached family to make Camera Matching easier in Revit:

(Make sure to measure your location when shooting the photo to be matched)

• Place the the family in the project, at the same location and direction as you real photo.
• Change the "Camera Height" and "Target Height" in the family to match your real photo (Instance parameters).
• Make sure the "Focal Length" is set to 23.7 mm (Instance Parameter), which apparently is the equalliant of the standard Revit Camera.
• Take note of the "Target Width" in the family, i.e. 4683 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Take note of the "Target Height" in the family, i.e. 3122 mm if the Focal Length = 23.7 and the Camera Distance is 5000 mm
• Place a Revit Camera on top of the Family, with the same direction and length.
• Go to the Camera view and change the Crop Size width to 4683 mm (Target Width) - Make sure to check "Scale (Locked Proportions)"
• Now change the Crop Size Height to 3122 (Target Height) - Make sure to check "Field of View"

You should now have a Revit Camera that matches the Family, but to make it all fit the actual photo:

• Open the photo, and in the properties take note of the Focal Length, i.e. 18 mm if you used a wide angle lense.
• In the family, change the "Focal Length" to match the photo properties, i.e. 18 mm
• Take a new note of the changed "Target Width" and "Target Height" (6167 mm and 4111 mm if you followed the above examples)
• In the camera view, change the Crop Size to match the above - Make sure to check "Field of View"

Your camera view should now be a pretty exact match of the photo!

Disclaimer:
The attached family is based on the physics of a Canon EOS 1000D, and is being calculated based on the formulas at Wikipedia - Use at own risk.

[Alex Page]

I believe you need to have measured where the photo was taken from - you cant follow these procedures without knowing the location of the camera when the photo was taken