Lens mounted 2" filters

[tooth_dr]

I'm considering mounting a filter either in front of a lens or inside of the camera (Nikon D800E).  The latter is more expensive and only available in limited types, but clearly the more versatile option meaning I can use the camera with both a scope or lens.

As an aside I am going to use step down rings to reduce the aperture of my 180mm lens, as it performs better at F4, and I dont like the spikes that the diaphragm makes.  Reducing from the fully open aperture of 65mm to 45mm means F2.8 to F4.  45mm also conveniently corresponds to the size of the inside of a M48 mounted filter, so a step down to a 48mm ring and then screw in the filter.

What would be the disadvantages of such a setup, and would these outweigh the benefits from an internally fitted clip in filter.

 

Thanks

Adam.

 

Edited November 23, 2020 by tooth_dr

[PeterCPC]

I have done something similar and just crop the vignetting.

[tooth_dr]

6 minutes ago, PeterCPC said:

I have done something similar and just crop the vignetting.

Thanks Peter.  I wasnt expecting much difference in vignetting, and maybe even a reduction in vignetting?  Did you see much difference?

[PeterCPC]

Not huge no.