Just messing around with MF lenses

That is manual Focus not oem M4/3 lenses - so this thread may not interest everybody. It might have been made for the “Adapted Lens Forum” but it is more an observation on how all lenses might work for manual focus on Panasonic bodies.

The cameras I have tested are: GM5, GX7 and GX85. The lenses I tested here are the somewhat odd combination of a Mamiya 150mm f2.8 Medium format lens adapted to EF and then focal reduced to M4/3 (completely dumb and no electronics) and the Canon EF 150mm f2.0 adapted to M4/3 with the cheap(ish) Jintu (Manual focus only) EF to M4/3 electronic adapter. But the issue of how all lenses work on these bodies remains much the same even with oem lenses in MF mode.

The odd lens combinations just add some spice and interest to the equation.

Firstly - I have mentioned before that I noticed that the GM5 with eye to evf will bring up (recover a lost) magnified evf screen either before or after a soft press very easily. This is done by a momentary touch anywhere on the lcd screen with the right thumb. I find this a very useful short cut when using a manual focus lens for the composition/focus routine.

The momentary touch will create an enlarged centre patch on the screen followed by a slight pause and then magnified full screen. Possibly this is a product of my camera settings - if others cannot easily replicate this then we will have to compare notes. But if the thumb is held touched for too long the point of focus might move as well.

Of course once magnified the level of magnification can be easily adjusted by rotating the back wheel. The whole effect is pleasing and makes for intuitive control.

It works for the the three camera bodies that I have noted.  But eye has to be applied to evf - eye switch on.

The Jintu adapter seems basically the Jintu AF version crippled by removing its AF function entirely. I suspect that the AF function would be a bit of hit or miss anyway as the cheaper Chinese EF electronic adapters do not have the depth of research into lens compatabilty nor do they have USB connection ports to easily upgrade their firmware. But for those that might consider using EF lenses in MF mode only the Jintu does provide full commnication between camera body and lens and aperture control via camera. Therefore it is streets ahead of a dumb EF to M4/3 adapter and does have the advantage over a dumb adapter with an iris control by actually using and reporting the setting of the iris in the lens itself. All that for much the same price. The only thing that does not work that I know of is that the old Canon EF 85mm f1.2 fly by wire focus is not operative - pity.

The GX85 has no manual AF/MF switch and seemed initially to have some issues with my thumb touch screen magnification but after some remounts and setting the Fn1 to the AF/MF switch it now recognises the Jintu combination in the same manner as the other camera bodies.  Not sure how it “learned” this ...  The switch provides a simple toggle AF-MF but for all intents and purposes it works as a manal focus lens attachment even when set to “AF”.  However the other lens combination does not even allow the Fn1 toggle to appear at all and just operates as a straight MF lens automatically without communicating the fact to the user.

I presume that because the Jintu has some communication with the camera body it falls into some form of no-man’s land communication.  The AF/MF toggle works becase the camera recognises that a lens is attached by the electronics but as it is not getting any auto focus feedback from the soft shutter press the firmware then reacts as if it was a connected AF lens used in MF mode and ignores the AF setting on the camera body - exactly as one would require.

Nicely sorted out.