> ## Knowledge Base Index
> Fetch the complete knowledge base index at: https://help.metareal.com/sitemap.xml
> Use this file to discover available pages before exploring further.
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# Reference Panorama

## Reference Panorama

The reference panorama, not to be confused with the blend reference, is the panorama image that is used as a reference for the reconstructed room. 

Its location is set at the origin and the 3D geometry is built around that origin. The orientation of the reference panorama determines the general orientation of the room geometry.

![](https://storage.crisp.chat/users/helpdesk/website/-/4/4/b/1/44b194dc9cade800/image_7y24j0.png =306xauto)

### Make Reference

To make a panorama the room reference panorama, select it from the image list, and then hit **MAKE REFERENCE** in the helper panel. The R icon should appear on the tile to indicate that this image is now the reference.

![](https://storage.crisp.chat/users/helpdesk/website/9dbb81a4a9968000/9017a1e5-5ad9-4c7c-a8a6-3d4bc9_19g69bc.png)

Once a panorama is set to be the Reference Panorama, the helper panel now enables the reference panorama tools.


## Aligning the Reference Panorama

The reference panorama needs to be levelled and correctly aligned to help reconstruction be as accurate as possible. To show the alignment guides, hit **Show alignment tools**.

The red line will show the current floor orientation, and the blue lines will show the levelling.

By default, Metareal's AI technology will level all panoramas automatically. You only need to manually add vertical level lines if you think that the automatic levelling hasn't done a good job, which usually only occurs in cases where there's poor lighting, image distortion, or image stitching errors. 

![](https://storage.crisp.chat/users/helpdesk/website/943fb0dff9fb0800/46d60ab8-bb53-47b5-b3b6-58ba2b_dj388p.png)

To change the orientation of the room and align on image features, drag the handle. For example, we are going to align the orientation of the room with the tiles on the floor. Note that using the PLAN VIEW mode helps a lot for this task.

![](https://storage.crisp.chat/users/helpdesk/website/92810d6eb46c1800/2603c91e-3dde-4808-818a-036298_zk0b9m.png)

![](https://storage.crisp.chat/users/helpdesk/website/ccaec285072c880/c4f82fdc-0de0-4478-89a9-22991a_i3147c.png)

Note how the grid is also aligned with the floor tiles. This makes reconstruction a lot easier, because angle snapping will be aligned with the room features.

![](https://storage.crisp.chat/users/helpdesk/website/5ac8d3f226ee1800/d007b25c-a8f9-4aa9-9213-84a74f_16rtjre.png)

Good features to use for the orientation alignment tool are bases of walls or floor tiles if not available

## Levelling the Reference Panorama

If you do need to level the reference panorama, switch to the **LEVELLING VIEW** mode.

![](https://storage.crisp.chat/users/helpdesk/website/7f3f2a2766452000/47225bd9-bb91-4441-8b81-064472_1kohbub.png)

This will display an alignment grid that will make the levelling process more precise.

To create a new leveling guide, first, spot a good vertical feature. Wall corners make great candidates.

![](https://storage.crisp.chat/users/helpdesk/website/31898e49b774ba00/515ab8f0-fca0-4014-baa6-852bdc_iq671c.png)

Hit **DRAW LEVEL LINE**, then click where the first end of the guide should appear and click a second time where the second end of the guide should appear. The accuracy of the levelling will increase the longer the guide is.

![](https://storage.crisp.chat/users/helpdesk/website/2f8694fb352ac200/fa7e3e01-9699-4b6c-ab3f-a4d0b4_wrnrak.png)

The panorama should level itself. To check if the levelling is accurate enough, use the grid in the **LEVELLING VIEW**.

![](https://storage.crisp.chat/users/helpdesk/website/fdad067e23dc8000/0f8e0913-c0d0-497e-8e27-b57224_11m9jr0.png)

Continue adding vertical guides in areas that aren't aligned correctly until you have reached a level of quality that is satisfactory. For example, looking around here, we can spot another corner that is slanted.

![](https://storage.crisp.chat/users/helpdesk/website/bfcdd7ebb13ea000/6c0ce941-585e-4aee-bbd3-14131a_ddlhkj.png)

Adding another guide will level the entire panorama so that on average, the vertical lines stay vertical.

![](https://storage.crisp.chat/users/helpdesk/website/d343123fbb509800/bb31a3a9-1731-4221-8efc-2feb04_14g7i3d.png)

You can also adjust existing levelling guides by dragging one of their handles.

![](https://storage.crisp.chat/users/helpdesk/website/78f3e7dc24082400/188c7f9e-a3a4-4b06-b519-9c39d9_1pqa1bm.png)

To delete a level guide, select it and press the **DELETE** or **BACKSPACE** key.

Once the orientation and the levelling is good, turn off **Show alignment tools** so the guides won't get in the way.

## Camera Parameters

![](https://storage.crisp.chat/users/helpdesk/website/-/4/4/b/1/44b194dc9cade800/image_107rgyn.png =369xauto)These are the camera properties for the current panorama.


## Lens Height

Sets the height of the nodal point (center of the lens of the camera) to the floor. This needs to be measured accurately during shooting. The accuracy of the room dimensions depends highly on the precision of this value.

## Nadir

Sets a masking circle that includes unwanted features at the nadir of the image, such as tripods.

![](https://storage.crisp.chat/users/helpdesk/website/acd65b4fa0a8900/0b9c0c05-bb25-4da8-a9a5-abd5ba_1lpexur.png)

Adjust it as tightly as possible to avoid wasting too much pixels in the image. To do this, either enter a numerical value, or use the **MEASURE** tool. When using the **MEASURE** tool, first, hit the **MEASURE** button.

Then click once in the viewport and move the mouse to set the radius of the nadir zone.

![](https://storage.crisp.chat/users/helpdesk/website/d6f46ccad1447800/fb93894e-34fb-4d38-abc1-a2921b_1emecvc.png)

Then click again to set the value.


Check **Also apply to Zenith** to mask the zenith of the image with the same radius. This is useful for stitched panoramas without a top image.