A call to any GH2 testers or people who get the camera early

J

Jay Birch

Well-known member
Please do some tests with the tele extender feature.

This really excites me... hopefully we will be getting a bonus 1/2" camera with no aliasing, no moire and well resolved images... if we can capture 4:4:2 to a hdmi device, even better.

Of course, it will be harder to get wide shots and shallow DOF... but it could still be a great feature.
 
I don't know that it will be super hard to get wide with the crop mode...isn't a lot of half-inch glass like 4mm on the wide end? Not the widest thing ever after crop but not too bad.
 
Will 1/2" f1.2 tv lens do it? With 2.6x, I'm guessing it would still lose some pixels at 16:9 mode.

2/3" tv lens is much bigger than 1/2" lens.
 
Vitaliy Kiselev said:
;-)
What do you want to know?

In fact, all works and very good.
You just need good and very sharp lens :-)
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I for one would really like to see how it handles shake for unstabilized lenses. It won’t have the depth of field problems that a fast telephoto lens might have. However, it will have the translation problems that unstabilized telephoto lenses have.

I would also like to know if there is a quick and easy way to trigger the extended telephoto feature with a one button click.

Additionally, does it affect auto focus at all?
 
Which c-mount adapter did you use? Did you mod it? One thing I don't like about C-mount lenses is that there seems no standard for the outer rings.
 
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mpgxsvcd said:
I for one would really like to see how it handles shake for unstabilized lenses. It won’t have the depth of field problems that a fast telephoto lens might have. However, it will have the translation problems that unstabilized telephoto lenses have.

I would also like to know if there is a quick and easy way to trigger the extended telephoto feature with a one button click.

Additionally, does it affect auto focus at all?
Click to expand...

It handles shake like for any other unstabilized lens :-)
Just shake will be 2.6x times larger for same focal length :-)
And DOF will be same as on telephoto lenses.
For one button I do not know, and I can't figure out why someone want to do this.
 
Vitaliy Kiselev said:
It handles shake like for any other unstabilized lens :-)
Just shake will be 2.6x times larger for same focal length :-)
And DOF will be same as on telephoto lenses.
For one button I do not know, and I can't figure out why someone want to do this.
Click to expand...

I thought the DOF will be the same as using that same lens without the teleconverter feature. It should not be the same as a lens with twice the focal length and the same Aperture F number, though.

I would want a one button click so I could use a fixed focal length lens the same way I use a zoom lens. I would shoot something near, stop filming, switch to teleconverter mode quickly, and film a close-up. Then I could easily piece the clips together and never need a zoom lens.
 
I think shake will be much less for those 1/2" tv lens as vignetting is so severe that 1:1 cropping will retain most of FOV. 16:9 mode has 1.8x crop factor. I'm guessing 2.2x crop factor for 1.2" tv lens after 2.6x 1:1 cropping.

DOF... cropping affects the circle of confusion. It deepens DOF.

I'm expecting deep DOF and good low light performance from the tv lenses.
 
I don't want to start another discussion about DOF here.
As you already could check DOF.
Get 85mm F1.4 shoot still image at 1920x1080.
Shoot same at highest 16:9 resolution using 30mm F1.4 and original 85mm.
Crop 1920x1080 central part.
Compare.
 
What i'd really like to know is whether the aliasing/moire really is gone and whether it resolves as well as, if not better than, the GH2 normal footage.
 
In all samples that I have I don't see moire.
But remember that it is preliminary firmware and it is not very detailed tests.
As for resolution - it is 1080p, but all depends on lens.
As only best lenses could provide very good sharpness in pixel level on such high pixel count sensor.
 
Vitaliy Kiselev said:
In all samples that I have I don't see moire.
But remember that it is preliminary firmware and it is not very detailed tests.
As for resolution - it is 1080p, but all depends on lens.
As only best lenses could provide very good sharpness in pixel level on such high pixel count sensor.
Click to expand...

What lens was used for the tests you have seen? 14-140mm? 20mm?
 
stockfuel said:
yes, but 1080p doesn't often mean 1.9k resolved lines.... I think GH1 resolves around 1k lines?

I was thinking though, as the crop is not have to pixel bin... maybe we might get the full 1.9k lines.
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The only camera to acheive 1000 horizontal lines of resolution is the Panasonic HDC-SDT750 and its derivatives. Although I don't agree with their way of testing resolution by outputting the source as 1080i to a TV.

http://www.camcorderinfo.com/conten...r-Review/Motion-amp-Sharpness-Performance.htm

The GH1 could only muster 750 horizontal lines which is not really that much more than the GF1 and G2 at 575 lines.

http://www.digitalcamerainfo.com/co...-Review-20751/Video-Motion-amp;-Sharpness.htm

http://www.digitalcamerainfo.com/co...ideo-Motion-amp;-Sharpness.htm#videosharpness
 
Vitaliy Kiselev said:
45mm macro that is sharp and 100-300mm that is not so sharp.
But as I said, more tests must be made with final revisions.
Click to expand...

Thanks for your preliminary thoughts. I understand that we need to wait for full results. It is disappointing to here the 100-300mm is not so sharp though. I guess I am glad I bought the 45-200mm instead.
 
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