Antares Barlows

[umbilic]

I have tried Antares Barlows (2x and 1.5x) for lunar photography using an IR pass filter a ZWO 290mm and a Celestron11 CPC but have been disappointed by the extra apparantly scattered light they produce Is it just me ? or is this due to say different transmissabilty of IR by the glass or something else - internal scattering ?

[Alan64]

The mirrors of any telescope scatter light more than lenses do.  There is the option of disassembling the barlows, to check for proper blackening of the housing and the edges of the lenses.  If sub-par or nonexistent...