Sensor size

[bosun21]

What is the largest sensor size that can be used before having to move up to 2” filters?. I have an ASI585 MC at present and was thinking about buying a camera with a larger sensor. Thanks 

[DaveS]

APS-C sensors can be used with 36mm unmounted filters, beyond that 50mm round unmounted are needed.

[vlaiv]

Depends on sensor-filter distance, F/ratio of the optics and amount of vignetting you are willing to accept, but in general - you want diagonal of sensor to be slightly smaller than the filter diameter (clear aperture).

For 1.25" filters - you have something like 27mm of clear aperture so you want to limit your sensor to 4/3 (which have diagonal of about 22-23mm).

APS-C is 28mm so you need 36mm filters and so on ...

[scotty38]

I'd go for a size that will last you some time.

I have 36mm filters with my 294m but I bought at that size for when/if I buy an APS-C sized sensor. I don't think I'll be going full frame any time soon so 36mm is future proofed enough for me.