will the lens CANON FD 17mm's 72mm front thread fit perfectly onto LA7200 72mm thread?
^^^^ this.
Me too.
@chinyew I don't know about the Canon lens, but the LA7200's rear glass element extends so far back it can hit the glass of the lenses it is attached to.
Like most users, I took the filter lens out of a 72mm UV filter and use the 72>72mm ring as a spacer to give more throw to the rear.
The whole point of the measurement classification for threading is so that you what fits what. A 72mm threaded accessory or filter will fit any 72mm threaded lens. Whether or not the LA7200 will perform well on the 17mm is another question entirely!
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