Question:

I was searching for the spectral properties of various smartphone cameras to see if we can use the camera sensors in smartphones as day time star cameras for our telescope. We just need a good NIR sensitivity (up to 1000nm) and a good filter to cut off the visible light.

I will eventually need to change the optics on top of the smartphone to significantly increase the zoom and end up with ~1 degree field of view.

It seems like you have experimented a lot with such problems and have learned from your investigations. What are your suggestions?

Answer:

The Nexus 5X has best sensitivity at 1000nm among the smartphones we're offering. 

Below are a few links to our YouTube videos and a website article that are relating to your application:

1. Please watch this video link (toward the end) where we demo 1050nm fluorescence markers.
2. This video link compares (toward the end) the Nexus 5X spectral response at 1050nm vs iPhone 6 plus.
3. You can rig up something like we showed in Figure 17 near the end of our website article to test your idea.  We used a Pentax riffle scope to narrow the FOV of closeup viewing at night and looking at a school over 1.5 miles away at night time but with street lights in the parking lot.
4. It's best to use a long pass NIR filter if you don't need visible light to increase S/N.