GH2 Tele Conversion Function

J

J Bellari

Active member
Using 24p cinema setting with the Tele Conversion Function provides an effective center of lens crop factor of approximately 5.2 ... is it possible to dolly, pan, zoom, rack focus and shoot handheld without shaking the camera substantially?

Unless shooting locked off exclusively, does that mean OIS are lenses really needed to minimize camera shake with this function?

Any examples and suggestions may help- thanks for the input!



REFERENCE: Per Panasonic's website "The Extra Tele Conversion function virtually extends the zoom range up to 2.6x, thus the max. 728mm* in AVCHD Cinema / FSH mode, max. 1,092mm* in AVCHD SH mode and Motion JPEG HD / WVGA mode and max.1,344mm* in Motion JPEG VGA / QVGA mode is available with the LUMIX G VARIO HD 14-140mm / F4.0-5.8 ASPH. / MEGA O.I.S. which is developed to be exclusively compatible with movie recording.

* 35mm camera equivalent."
 
More stabilization is always needed whenever you have higher zooms no matter how the zoom is implemented.
 
can someone tell me what's the widest FOV i can get with the EX-TELE mode ? let's say i use an extreme wide fast c-mount lens ? what will i get if i'll use 6mm?
 
Barry_Green said:
In terms of a 35mm stills camera? Apparently about the equivalent of 31.2mm.
Click to expand...
thanks Barry.
and how would you imagine it would look on decent glass? will it pass the vignetting ? will the picture still have any wide feel to it ? i mean, it would look a bit different than putting a 15mm 4/3 lens...
will it be usable in narrative work?
 
roei z said:
thanks Barry.
and how would you imagine it would look on decent glass? will it pass the vignetting ? will the picture still have any wide feel to it ? i mean, it would look a bit different than putting a 15mm 4/3 lens...
will it be usable in narrative work?
Click to expand...
If you want wider, some CCTV c-mount lenses designed for machine vision (the so called "megapixel" lenses) are available for 1/2" sensors in 4.5mm, 4mm, even 3.5mm (multiply by 5.2 to get the 35mm equivalence), but they're not cheap. They'll cover the 720 1:1 crop for sure, they might vignette a little on the 1080 1:1 crop.

When the buzz about the crop mode started a month or two ago I researched these as a cheap substitute for wide angle coverage, but soon abandoned the idea. There's no way these can match the IQ of a Planar, Distagon, or the Panasonic pancake. Paying 150$ or more for these low-q lenses make very little sense AFAIC, but I might be proven wrong.

Right now, the best use of the crop mode would be with the Panasonic pancake I think. With just that discrete sharp lens attached to the GH2 you have a f1.7 normal and telephoto lens.

The need of a f2 or faster wide angle lens for the m43 format will be answered at one point, hopefully.
 
chon said:
If you want wider, some CCTV c-mount lenses designed for machine vision (the so called "megapixel" lenses) are available for 1/2" sensors in 4.5mm, 4mm, even 3.5mm (multiply by 5.2 to get the 35mm equivalence), but they're not cheap. They'll cover the 720 1:1 crop for sure, they might vignette a little on the 1080 1:1 crop.

When the buzz about the crop mode started a month or two ago I researched these as a cheap substitute for wide angle coverage, but soon abandoned the idea. There's no way these can match the IQ of a Planar, Distagon, or the Panasonic pancake. Paying 150$ or more for these low-q lenses make very little sense AFAIC, but I might be proven wrong.

Right now, the best use of the crop mode would be with the Panasonic pancake I think. With just that discrete sharp lens attached to the GH2 you have a f1.7 normal and telephoto lens.

The need of a f2 or faster wide angle lens for the m43 format will be answered at one point, hopefully.
Click to expand...

thanks..
yea i think it's a bit impractical for narrative work.. you can't go wider than 50mm (let's say using cine 16mm c-mount 10mm wide).. tried looking around for good cine 6mm, but they only come in bolex 8mm mode c-mount, and unusable (explained by Barry)
 
Crop Factor

35mm = 1
super 16 = 2.97
2/3" = 3.93
GH2 1080 = 1.8 x 2.6 = 4.68
1/2" = 5.41
GH2 720 = 1.8 x 3.9 = 7.02
1/3" = 7.21

Theoretically 2/3" lens will not vignette but 1/2" lens will vignette on the GH2 1080 mode,
try to use those numbers to figure if a certain lens will vignette on the GH2.
 
thanks..
yea i think it's a bit impractical for narrative work.. you can't go wider than 50mm (let's say using cine 16mm c-mount 10mm wide).. tried looking around for good cine 6mm, but they only come in bolex 8mm mode c-mount, and unusable (explained by Barry)
Click to expand...

Some of the 10mm Switars, which were often used on Bolex H16s, also came with the 5mm Aspheron wide angle adapter. If you can find either of these at a sensible price nowadays, you'll be very lucky.
 
AdrianF said:
Some of the 10mm Switars, which were often used on Bolex H16s, also came with the 5mm Aspheron wide angle adapter. If you can find either of these at a sensible price nowadays, you'll be very lucky.
Click to expand...

you mean this:Lens12-27A.jpg?
the one on the left? seems pricey and troublesome...
 
Yep, my bad the Aspheron is actually a 5.5mm. These were also made for the Vario Switar 100 12.5-100mm zooms, which I used to have a bayonet version of. I'm looking in the Bolex Bible at the moment and these were also produced in a c-mount version. I'd love to see how this combination would work with the tele crop. It could potentially be a great combo for run n gun type shooting, as you'd have a fast and reasonably wide zoom with a long range.
 
but will it ever look wide enough? even with supposably 30mm FOV of the 6mm lens...
i mean, look at : http://www.abelcine.com/fov/
and take, let's say: 5d against the 2/3rd inch HD- you realize at this crop - you'll never "feel" wide.

* anyway- i believe the wide adapter price is around-
http://cgi.ebay.com/Century-Precisi...92706197?pt=Camera_Lenses&hash=item4cf2e67d95

and the 10mm is around-
http://cgi.ebay.com/KERN-SWITAR-PRE...80654692?pt=Camera_Lenses&hash=item4153e90664

so if you go for all that trouble and not getting wide enough for run 'n gun...
 
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Using the tele mode to achieve a super wide angle isn't really playing to it's strengths. This should give you a workable zoom range with the addition of the adapter, in theory.
Don't forget a lot of fixed lens prosumer cams like the HVX and Z1s, for example have zooms in this range. The thing is with these, you can then add an adapter if you need super wide.

Around 30mm is perfectly workable in a lot of situations.

Just cheked the Aspheron for the Vario Switar zooms was actually a 6.5mm.
 
but you must realize that this "30mm" wide FOV will not look the same as 15mm 4/3 lens. i don't think you'll be able to feel wide (as you can see from the crop calculator)
. but maybe i'm wrong.
 
Well we really don't know for sure how it's going to look until somebody get's to try it, but I calculate that a Vario Switar zoom mounted with a 6.5mm Aspheron in tele crop mode, should work out something like using a 17mm in m4/3. Not too bad.

These are heavy lenses, so the connection could be a bit tender
 
The Panasonic 14mm f2.5 is $400 at amazon. It's brand new, lightweight, small, has AF and you won't be limited to ISO 800 due to larger noise patterns. Beats that contraption on every aspect but speed.
 
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