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

mpgxsvcd said:
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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I suggest you to wait and think.
As both zooms won't be super sharp wide open.
But closed down they'll be better.
Plus 100-300mm for 2.6x crop mode is quite strange choice.

Most probably you need something in 4mm to 100mm range here.
And you really want either very good B4 or C mount lenses or best still lenses.
 
mpgxsvcd said:
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
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If I read that report correctly, they're saying that the GH1's FHD video resolution is actually only about 750x650. Since that's much less than the native resolution of the image sensor, it must be the effective resolution of the proprietary scaling algorithm the camera uses to produce a 1920x1080 video frame. If that's what was required to reduce video moire patterns, then increasing the GH2 sensor's pixel count may actually turn out to improve video resolution.
 
lpowell said:
If I read that report correctly, they're saying that the GH1's FHD video resolution is actually only about 750x650. Since that's much less than the native resolution of the image sensor, it must be the effective resolution of the proprietary scaling algorithm the camera uses to produce a 1920x1080 video frame. If that's what was required to reduce video moire patterns, then increasing the GH2 sensor's pixel count may actually turn out to improve video resolution.
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Let's hope that is the case.
 
Vitaliy Kiselev said:
I suggest you to wait and think.
As both zooms won't be super sharp wide open.
But closed down they'll be better.
Plus 100-300mm for 2.6x crop mode is quite strange choice.

Most probably you need something in 4mm to 100mm range here.
And you really want either very good B4 or C mount lenses or best still lenses.
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In my opinion stopping down the zoom lenses is worthless for the pictures I shoot. They already have such small apertures that closing them up further means very high ISOs and too much noise. For stationary shots they should be fine though.

I think the 300mm with the 3.9x crop mode would be ideal for 720p videos of the moon. At 2400mm equivalent the moon should just fill the frame perfectly. I know most people won’t shoot like this often but it will be nice to have for those of us who do.

http://www.youtube.com/watch?v=FdkhZ0-ZAtk
 
Vitaliy Kiselev said:
Most probably you need something in 4mm to 100mm range here.
And you really want either very good B4 or C mount lenses or best still lenses.
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I will use the 14mm to get 14mm, 35mm, and 55mm. And I will use the 20mm to get 20mm, 52mm, and 78mm. Without IS that is about as far as you can go. I might use the 45-200mm to get 117mm and 175mm but you cannot hand hold video any further than that even with IS.
 
ETC feature is good only if the cropped section is already sharp? If so, I better use a tripod when using the feature.

20mm * 1.8 * 2.6 = 93.6mm
50mm * 1.8 = 90mm

2.5x ETC on the pancake will be harder than using the nifty fifty.

BTW it would be nice to change the setting from the touchscreen LCD.
 
Vitaliy Kiselev said:
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.
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Vitaliy (sorry I was spelling your name wrongly all these days), thanks for the early feedback.

Very excited about the 1:1 pixel feature. Just wondering why the lens sharpness matters more in 1:1 pixel mode? I was thinking it would matter less because there is no scaling and it would do away with sharpness loss from the scaling algorithms? Please correct me, if am wrong.
 
Black_Ste said:
Very excited about the 1:1 pixel feature. Just wondering why the lens sharpness matters more in 1:1 pixel mode? I was thinking it would matter less because there is no scaling and it would do away with sharpness loss from the scaling algorithms? Please correct me, if am wrong.
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In 1:1 pixel mode a center portion of an 18 MP sensor is extracted, so there is no resolution loss due to aliasing, but lens must be sharp enough to resolve this 1920 x 1080 extract, which covers a little over 12% of the sensor. As a rule of thumb, if a lens is sharp enough to take photos (when 100% crops are examined) it is sharp enough for Ext. Tele Function (1:1 pixel mode).
 
Vitaliy Kiselev said:
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.
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I came across an interesting feature on the GF1 last night while doing the testing Vitaliy suggested. It appears that the GF1/GH1 have an extra optical zoom feature. It allows a 2x zoom in 1920x1080 still image mode. It is not a 1:1 pixel mapping mode and it is only available for stills. However, it can give you a good idea of what will be possible with the extended teleconverter feature of the GH2.

What will be really interesting to see is what happens when you stack the zooms on each other. I wonder what the 45-200mm lens or my 400mm MF lens would look like with the 3.9x zoom or with the 3.9x + 2x digital zoom? You could get some pretty tight videos with those combinations.

Here is a link to some of the sample images I took when trying to simulate the extended teleconversion feature.


http://www.dpreview.com/galleries/4222674355/albums/extended-teleconversion
 
Hmmm... Fujinon 12.5-75mm f1.2 is designed for 2/3" sensor. M43 sensor is 4/3". So the lens negates 2x crop from 2.6x cropping. Then it becomes 20-120mm in m43 format. That is less wide and less long than the kit zoom. DOF is f/1.9 in m43 format. That's 2-3 times faster than the kit zoom. Hopefully its center cropping is sharp enough. If yes, this could be my indoor event shooting lens. Sometimes there is no time to switch primes.

Now it's waiting game.
 
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I think it should be more like 32.5-195mm after a 2.6x crop. If you set it to 12.5mm and don't teleconvert, you're getting the image cast by a 12.5mm lens -- it just doesn't cover the entire sensor. Simply multiplying either extreme by 2.6 should give you accurate numbers.
 
The lens can't cover the entire m43 sensor. 4/3":2/3" = 2:1. When 2.6x ETC (extra tele conv) feature is applied, it's only 1.6x cropping for the lens. Multiply 1.6 on the range and f-number. The Fujinon lens becomes 20-120mm f/1.9 in m43 format.

2.6x multiplier applies to those lenses that cover entire m43 sensor. 1/2" tv lenses have 1x multiplier. It covers just enough of 2.6x ETC sensor area. That's why the ETC feature is a godsend for those tv lens owners.

I prefer 2/3" tv lenses over 1/2" as its center will be sharper.
 
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I recognize that it won't cover the sensor. On a 2/3" sensor, the 12.5-75mm range is equivalent to 25-147 on a 4/3s camera. By applying a 2.6x conversion, you're effectively using a sensor with an 8.3mm diagonal -- in other words you're cutting into normal FOV of a 2/3" sensor (which has an 11mm diagonal.)

If I do (11/8.3)x25, I get 33.13. (11/8.3)x147, and I get 194.82. Rounded off, I get an effective range of 33-195mm, the equivalent of 66-390mm on a 35mm sensor.

Because you have to cut past the intended focal range of lens, it seems to me that 1/2" sensor lenses are a somewhat better match for the tele-conversion feature, since the sensors they were made for had a 8mm diagonal.
 
All correct except the 1st part. Before 2.6x conversion, 12.5-75mm on 2/3" sensor is still 12.5-75mm on m43 sensor.

Yeah... I will stop talking about FOV.
 
Sure, but it also doesn't fill the sensor. A 12.5-75mm lens on a 2/3" sensor camera is the equivalent, FOV-wise, of a 49-295mm lens on a 35mm camera. If the teleconversion feature could do 2x instead of 2.6x, that's about the range you'd get in terms of FOV, but instead it zooms further in.

Sounds good, no more FOV talk, starting now.
 
svecher said:
In 1:1 pixel mode a center portion of an 18 MP sensor is extracted, so there is no resolution loss due to aliasing, but lens must be sharp enough to resolve this 1920 x 1080 extract, which covers a little over 12% of the sensor. As a rule of thumb, if a lens is sharp enough to take photos (when 100% crops are examined) it is sharp enough for Ext. Tele Function (1:1 pixel mode).
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Thanks. That make sense.
 
If you want to get an idea of what the quality of the crop mode movie might look like, imaging-resource posted a small one in VGA size on their website when they reviewed the T2i. The link to the actual crop movie is:

http://216.18.212.226/PRODS/T2I/FULLRES/YMVI_2556.MOV

You can also go to their website to see what an standard VGA movie looks like (it's a lot sharper). To me the crop mode looks exactly like a bunch of stills viewed at 100% because, well, that's what it is.
 
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