Lumix G X Vario 12-35mm f/2.8 Asph. Lens

[bruce southerland]

I will be using this lens with the AF100 for a shoot & don't have the time to test it.
To those of you that have used the lens, does it look good at
f2.8(sharpness, color shift, etc..)? Any other advice about this lens would be appreciated!

 

[little bobby]

I really like this lens. No color shift from the stuff I've shot. Be sure to white and black balance. Just remember that it is varifocal and will not hold focus while zooming. The iris will also flicker slightly while zooming. Should be used as a "variable prime."

 

[funkytwig]

I really like this lens. No color shift from the stuff I've shot. Be sure to white and black balance. Just remember that it is varifocal and will not hold focus while zooming. The iris will also flicker slightly while zooming. Should be used as a "variable prime."

True it is opticaly variforcal but through clever tricks the camera compensates (like the z1) and it behaves parfocal. I was doing some low light tests and it certainly seems to work.

Not even Canon make any lenses for the C300 that do this.

Ben

 

[trw_mavrik]

Hi

Im having trouble with the autofocus on this lens when dollying in. Is anyone else having this problem?

Regards

Y

 

[funkytwig]

Ime having probems with autofocus an all my lenses);, but seriously it is very slugish and I am planing on staying away from it.

 

[little bobby]

True it is opticaly variforcal but through clever tricks the camera compensates (like the z1) and it behaves parfocal. I was doing some low light tests and it certainly seems to work.

Not even Canon make any lenses for the C300 that do this.

Ben

I think you are mistaken. This lens/camera combo does not behave parfocal, and I have never heard of these clever tricks. Can you elaborate?

Hi

Im having trouble with the autofocus on this lens when dollying in. Is anyone else having this problem?

Regards

Y

Try focusing manually, should solve your problem.

 

[funkytwig]

I beleve Limux 'HD' behave parfocal on AF100/101.

I beleve Limux 'HD' behave parfocal on AF100/101.

I think you are mistaken. This lens/camera combo does not behave parfocal, and I have never heard of these clever tricks. Can you elaborate?

Try focusing manually, should solve your problem.

Basically the focus srevo (or whatever it is called) compensates for the focus shift as you zoom. This is because the lenses are 'fly by wire'. The rings send electrical signals to the firmware which contols the lense hardware, i.e. there is not a machanical conection between ring and phisical lense elements. This is only normally possible with cameras without interchangeable lenses due to the tight integration but the HD lenses (think it is all of them but may be wrong) are designed for this.

I have not done a mass amount of testing as I havent had the AF101 for long but I did noticed that when using peaking (with DVF DTL off to increase acuracy) you can zoom in and focus (which reduced DOF) and then zoom out and more is shown in focus, converging on the point you focus on. The few tests I have done back this up. (i.e. i shoot using peeking and look at footage on a 32" display).

I think this may be in the AF100 book but I may of picked the info up somware else.

This all may seems a bit geeky but understanding how the camera works internaly is very usefull if you are a serious user. This also means the following (I consider usefull thisgs).


With natine codec (and probably all unless you are capturing RAW).

1. It is always better to add gain in camera than post (as the camera is adding gain on the RAW data and post is adding it to a heavely compressed image).
2. It is alway better to add detail in post (for the same reason, there is clever sharpening methods (which may do a very good job but wil be slow, the disadvantage the camera has is it has to do it real time but I think this is more than made up with by the advantage of using RAW data.

The AF100 book is great but does not mention the above. Possibly becasue it is basic stuff aplicable to most cameras and the 257 pases do crama lot in, well done Mr Green.

Ben