# Micro-Manager CSU-W1 dual camera setup: Can't address secondary dichroic

**URL:** <https://forum.microlist.org/t/micro-manager-csu-w1-dual-camera-setup-cant-address-secondary-dichroic/2489>\
**Category:** Software\
**Tags:** micro-manager, csu-w1\
**Created:** [April 9, 2024, 9:58am UTC](https://forum.microlist.org/t/micro-manager-csu-w1-dual-camera-setup-cant-address-secondary-dichroic/2489 "2024-04-09T09:58:51Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![CellKai](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@CellKai](https://forum.microlist.org/u/CellKai)\
**Post date:** [April 9, 2024, 9:58am UTC](https://forum.microlist.org/t/micro-manager-csu-w1-dual-camera-setup-cant-address-secondary-dichroic/2489/1 "2024-04-09T09:58:51Z")

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Hi,

I am in the process of setting up a dual camera CSU-W1 setup.

This is working well so far, except I seem to not be able to address the secondary dichroic / light path changer in micro manager. Is there a device for this? To elaborate, this secondary dichroic guides the light to camera 1 (empty or glass), camera 2 (mirror), or to both (long pass 561 nm beam splitter)

 ![image](https://us1.discourse-cdn.com/flex020/uploads/microlist/original/2X/3/35bbf01d68ae95966a26fbe2c882f78305fda145.jpeg)

When setting up the CSU-W1 in Micro-Manager, I can see the “CSU-W1 Dichroic Mirror”, but this is the main dichroic that separates the illumination and emission light. I also see indeed 2 filter wheels, one in front of each camera. But I don’t see the secondary dichroic.

 ![image](https://us1.discourse-cdn.com/flex020/uploads/microlist/original/2X/0/060da0a697123f59afc3653a5552b92f070e23a0.png)

Did anyone already set up Micro-Manger with dual-camera and a CSU-W1 unit? Is there maybe a device that I am somehow missing?

Thank you for your help!

ping @nico.stuurman (apologies for the many pings 😅 )

crosspost on github: [CSUW1 device adapter Dichroic misses a position · Issue #458 · micro-manager/mmCoreAndDevices · GitHub](https://github.com/micro-manager/mmCoreAndDevices/issues/458#issue-2233070590)

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<div class="post-metadata">

**Author:** ![CellKai](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@CellKai](https://forum.microlist.org/u/CellKai)\
**Post date:** [April 10, 2024, 7:10am UTC](https://forum.microlist.org/t/micro-manager-csu-w1-dual-camera-setup-cant-address-secondary-dichroic/2489/2 "2024-04-10T07:10:17Z")

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solved by @nico.stuurman on the GitHub issue.

The “image splitter” in MM is called “CSUW1-Port”