The formula i have used in the past for calculating nearest and farthest distance when using lenses and adapter of closeup-lenses does not work.
I want to compare two exotic combinations.
I know one lens on pentax 67 is focussing to 7m only-good for portraits. i dont have that camera anymore.
Now the same lens with different adapter (hasselblad-nikon) i want to use on a hasselblad.
I can remove the nikon-ring-maybe its t2. see my other tread about stuck screws.
All i can calculate is the difference.
on pentax 67(register 84.95mm i get 7m max.
with hasselblad-ring(nikon removed) 14mm will be added but register is 74.90(Hasselblad)
do i now have a difference of 84.95 minus 74.90 plus 14mm? 24mm
whats the formula for farthest distance comparing these 7m plus using closeup-ring 24mm, the complete adapter for hasselblad instead of pentax67? maybe i was wrong an additional 6mm must be added. i removed the lens-adapter.
Its a 35mm -lens with big aperture. when lens-adapter i attached i am calculating 16mm closeup-lens to match m-42-camera and infinity. by removing these 16mm i can focus to 7m max.(lens set to infinity).
so when removing 35mm-adapter from t2 i get 2mm less, these 14mm.
first lets calculate the max. distance if i would use pentax 67 adding 14mm closeup-lens.
without i get 7m.
whats the formula?
2. do i simply have to use 30mm(10+14+6)?
Actually i have a multiring-combination for Pentacon-Six plus m-42-adapter plus C/Y-ring
ratio at infinity is 5:1 or 1:5 if the latter is correct. 180mm over 36mm film .
If only pentacon-six i get 26mm farther away comparing without-holding the naked lens-without any adapter to pentax 67 where i get 7m max.
Was it too complicated.
I first removed that special adapter containing t2 of a high-speed 35mm lens. then i hold it to pentax 67 and got 7m maximum when set at infinity.
for pentacon six 60mm must be added for the adapter. i could tape the oringinal short p-six-ring(7.5mm?) to the lens.
How is max. distance calculated for p-six knowing without 60mm closeup one can go to 7mm on pentax 67.
As a said i have a formula but when checking with contax and its closeup lens with 45mm i received a different distance than what the viewfinder showed....
I want to compare two exotic combinations.
I know one lens on pentax 67 is focussing to 7m only-good for portraits. i dont have that camera anymore.
Now the same lens with different adapter (hasselblad-nikon) i want to use on a hasselblad.
I can remove the nikon-ring-maybe its t2. see my other tread about stuck screws.
All i can calculate is the difference.
on pentax 67(register 84.95mm i get 7m max.
with hasselblad-ring(nikon removed) 14mm will be added but register is 74.90(Hasselblad)
do i now have a difference of 84.95 minus 74.90 plus 14mm? 24mm
whats the formula for farthest distance comparing these 7m plus using closeup-ring 24mm, the complete adapter for hasselblad instead of pentax67? maybe i was wrong an additional 6mm must be added. i removed the lens-adapter.
Its a 35mm -lens with big aperture. when lens-adapter i attached i am calculating 16mm closeup-lens to match m-42-camera and infinity. by removing these 16mm i can focus to 7m max.(lens set to infinity).
so when removing 35mm-adapter from t2 i get 2mm less, these 14mm.
first lets calculate the max. distance if i would use pentax 67 adding 14mm closeup-lens.
without i get 7m.
whats the formula?
2. do i simply have to use 30mm(10+14+6)?
Actually i have a multiring-combination for Pentacon-Six plus m-42-adapter plus C/Y-ring
ratio at infinity is 5:1 or 1:5 if the latter is correct. 180mm over 36mm film .
If only pentacon-six i get 26mm farther away comparing without-holding the naked lens-without any adapter to pentax 67 where i get 7m max.
Was it too complicated.
I first removed that special adapter containing t2 of a high-speed 35mm lens. then i hold it to pentax 67 and got 7m maximum when set at infinity.
for pentacon six 60mm must be added for the adapter. i could tape the oringinal short p-six-ring(7.5mm?) to the lens.
How is max. distance calculated for p-six knowing without 60mm closeup one can go to 7mm on pentax 67.
As a said i have a formula but when checking with contax and its closeup lens with 45mm i received a different distance than what the viewfinder showed....
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