More on Helios 103 filter size

[oldgeezer]

I have measured the O.D. of the filter ring on the lens and it measures at 42.15mm, the filter ring is not dinged or dented and the filter threads are clean. The I.D. of the filter ring measures at 40.0mm. The O.D. of the 40.5mm Tiffen filter measured at the threads measures 40.35mm. Serial on lens 8143347.

 

[FrankS]

I believe that those fsu lenses take a 40.5 filter.

The vintage Canon ltm lenses are tricky, with a 40 filter iirc.

 

[Fotohuis]

Most FSU lenses have the 40,5mm filter size.

 

[julio1fer]

The Helios-103 takes 40.5mm filters (at least mine does).

It also takes very sharp pictures.

 

[David Hughes]

Hi,

Just seen a Jupiter 8 and filter etc advertised and the filter has "40,5 x 0,5" written on it. Hope that helps.

Regards, David

 

[Murray Kelly]

Could it be that there is some 'slop' to allow for small dings in the filter mount preventing an exact thread of 40.5mm from being mounted? It wouldn't take much to make it next to impossible to mount a filter under such a condition as an exact match.

 

[FrankS]

Use a loop, magnifying glass, or 50mm lens to examine the entry threads of both lens and filter and look for damage/deformation.