Miniscope Customization - Camera, Lens, Emission filter

[Caio Rímoli]

Dear all, 

I am using the latest version of the miniscope V4.4 for my specific application and I'm having a few problems that are limiting the technique I'm developing to be used in vivo:

- too much blue LED light is leaked to the camera when I try to use LED power above 50% of the scale so that the background due to LED is huge.

- the camera's bit depth (8bit) seems to be not ideal for me, 16 bit would be way better.

- spatial resolution is poor because for most people's applications that is not important, but for me it is, it would be great if I had a better spatial resolution (I don't need a big FoV. For example, if my FoV were ~400x400µm or even ~300x300µm it would be totally fine).

- Emission filter: can we choose a different emission, for example with a different EM window range? The EM central wavelength center is totally fine.

This is because, for my work, the spatial intensity details in the video of the Ca+2 events (GCamp8) are the key information.

As far as I searched on the previous conversation topics here, only Miguel (25-March-2021) asked about changing the miniscope LENS configuration for higher resolution, but I didn't get much information about customization of the detection path. 

Please, do you know what it is possible to do in order to adapt/customize the miniscope to reach closer to what I need?

Thank you very much for the support,

Cordially,

Caio VAZ RIMOLI
Postdoctoral researcher
LKB & IBENS, Paris, France

[Federico Sangiuliano]

Hello Caio.

1) The amount of LED intensity you need is mostly dependent on the expression of your fluorophore. When using Gcamp6 we never had to go further than a value of 10 on the scale in the GUI. For GCamP8 I would expect to use less light, not more. One thing you could try is increasing the gain to the max

2) There is no 16 bit image sensor that could fit on a microscope the size and weight of the Miniscope. And even if it was, the whole electronics would have to be redesigned to accommodate it

3) You could achieve that by redesigning the optical path, but changes will be substantial

4) You can change the filter set to accommodate the passbands you need. However for imaging GCaMP8 the emission filter (and the whole filter set) is adequate

I hope this helps

Federico