The needs of telescoping beams is often discussed in brief on several threads to expand or compress beams, I wondered if anyone would like to share experience in lens selection combination's for various magnifications.
Like for example, lets say we want to expand a beam:
1.5 x
2 x
3 x
4 x
And to compress it, am I right to understand reversing the same lens setups will do the compression to the same ratio.
Are these lens combination very related to the divergence of the initial beam or does that not matter as expansion also reduces divergence.
Would say a 2x expander work on almost any beam as long as its within a reasonable state of being called a beam.
Andy