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Fuji GFX with adapted lenses

adapter AF equivalency lens factor

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#1 zinertia2



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Posted 03 May 2017 - 01:49 AM

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Has anyone considered the Fringer Contax 645 adapter?   It looks pretty good w AF capabilities (but still during the development phase).


Also is there a way to determine the "equivalent" focal length?  The 645 being a bigger sensor, etc etc.


Is this as simple as using the different equivalency formula floating around on the web?   0.64 from 645 to 35mm full frame, similar to the 0.79 from the GFX to 35mm full frame.  (sorry I still think in 35mm)





#2 Jaco van Lith

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Posted 16 May 2017 - 02:29 PM

Why waisting money for an adapter. Contax lenses are "too long" for the GFX. So the Zeiss wide angle is a lesser wide angle, and the tele is more-long when it is mounted to the Fujifilm GFX 50S

Fuji should never had designed the GFX 50S. The camera is no Medium Size camera; the sensor is too small. It is an oversized ( amateur) Full Frame sensor. Professional photographers need a real medium size sensor (negative); SQUARE  60 x 60 mm like the Hasselblad 550 C/M or the Rolleiflex. 

The GFX -50S 33 x 44 mm sensor is too small, it looks like a Super Size 4 x 4 ( 38 x 38 mm ) slide. The rotating EVF of the GFX-50S has a limited possebility to rotate! Buy me a beer and I will tell you all the disadvantages of this new Fujifilm GFX 50S. 


Todays digital cameras look like PINBALL MACHINES. A photographer is a craftsman; no magician. They just press one button with a cable release.

Helas there is no common cable release which fits to any Fujifilm digital camera. 

I doubt whether the  new breed of the design department of Fujifilm digital cameras ever met a real photographer. Any way, it is clear they do know too few of the history of Fujifilm cpmpany. 


Since 1963 I buy Fuji camera's, optics, films, papers and chemicals 

#3 Jaco van Lith

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Posted 16 May 2017 - 06:15 PM

Equivalent ... ?  Think or start at 35 mm miniature film with the negative/sensor size of 24 x 36 mm = todays Full Frame.

Over the decades the 24 x 36 mm photocamera was sold with a 50 mm optic ( it varies from 40 up till 58 mm). The rangefinder camera, with the fixed standard optic, had a 45 mm optic. Like the Minolta, the first American camera in Space; bought a the drugstore at the end of a street in the U.S.A..

Oscar Barnack, the father of the Leica, prefered a 35 mm optic. He was right, 50 mm is too long for every day pictures.


For portraits anything between 80 and 105 mm will do. Never make portraits with the much too populair 135 mm. Wide angle 28 mm or 24 mm.

So we are finished ? Or do you want more mm ? For birds, sport, nature: 200 mm, 300 mm or 400 mm.

If you got no assistent to carry the load, get yourself two zoom optics, Forget Mister big-mouth-wise-guy, who tells Prime Optics are the best and oversized wide apertures are a must,nonsense !

Mr. Richard Avedon, David Bailey, August Sander etc. had no Bokeh photoos nor wide apertures. Stop down to f/11 or f/64. Use a tripod or 6400 ISO.


Do you know the analoge Olympus Pen F 18 x 24 mm, made in 1963 ? It had a standard 38 mm optic, terrible thing much too "long". Its little sister the Pen EE with a 28 mm, she was a beauty.


For Hasselblad 500 C/M some prefered a set of three optics: 50 mm, 80 mm and the 150 mm plus a small extension tube

Some did not like the 80 mm; a 60 mm or 100 mm thought to be nicer.

Today there is a crazy competition, who has got the shortest and who has got the longest optic. Do not forget to make photographs.


Take my advice. Read the story here below and forget it. Go to a decent photoshop and hold the camera and optics in your hand.



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