Quote:
Originally Posted by astro744
Interesting why John did not recommend the PTR-4201 adaptor as follows:
2a) Powermate 4x: Canon 5D --> CWT-2070 --> PTR-4201 --> Powermate 4x 2" --> Baader Visual Back 3.25 Clicklock
The only thing I can think of is the CTW-2070 does not fit the PTR-4201 in which case you would need a third party Canon T-Ring as follows:
2b) Powermate 4x: Canon 5D --> Canon T-Ring --> PTR-4201 --> Powermate 4x 2" --> Baader Visual Back 3.25 Clicklock
I'm sure both options work and maybe you get vignetting with the standard T-Ring option especially with a full frame 36 x 24mm camera.
Maybe ask John out of curiosity if you are likely to get vignetting with my option 2b) and also ask what is the magnification factor with his option 2), (not using PTR-4201). Is it still 4x?
Addendum:
Maybe ask John when is the PTR-4201 recommended?
|
Astro, in my haste to post this up while rushing to do other things, I forgot to mention he did in fact suggest the PTR-4201, in the configuration exactly as per your 2b). However, since you use a standard T ring in 2b) dont you get vignetting as you say?
He specifically suggests the RAD-1070 method for prime focus stating that it will help reduce vignetting, so I assumed this would also be best for the powermate added in as well!
I will ask him both of your questions Astro, will see what he says. He doesnt seem to want to reply anymore
