lens marking on camcorder

[dniwkh]

Hi,

I just bought a sony PJ650V.

I am wondering what are the markings on the front of the camera, it says 1,8/2,9-34,8

I am assuming that 1,8 is the max aperture while the 2,9-34,8 is the focal length of the lens.

Is from the 2,9 I can get the crop factor of the sensor inside.

Example, it is spec at 26.8mm at widest so the sensor size is roughly 2.9/26.8 vs FF.

Is that correct?

 

[astrocom]

Ouch that hurts - trying to understand what you are asking that is

Yes I think you are right that 1.8 is the max aperture.
2.9-34.8 is the focal length and your PJ650V should have 12X Optical Zoom (34.8/2.9 = 12).
I am assuming the PJ650 uses the same 6.3mm sensor as my NX30. Crop factors are calculated base on the diagonal sizes of the sensors.

For example a standard 35mm sensor is 36mmx24mm (Diagonally it's 43.3mm). So if the sensor of your PJ650V is 6.3mm, then the crop factor is 43.3/6.3 = 6.87X.
Then the zoom factor of PJ650 that is equivalent to a 35mm still camera will be about 20mm - 240mm (2.9*6.87=approx. 20mm) & (34.8*6.87= approx. 240mm).

The sensor size of your videocam can be found near the last few pages of the manual where the specifications are.

You can find more info at:
Making (some) sense out of sensor sizes: Digital Photography Review

 

[dniwkh]

no the PJ650 uses a smaller sensor.
according to this website
http://store.sony.com/p/Sony-32GB-Full-HD-Projector-Camcorder/en/p/HDRPJ650V#specifications

my sensor is 1/3.9" (4.6mm). This is weird because 1/3.9" is not 4.6mm....

if I use 4.6mm diagonal, then all the numbers add up.

The new camcorders all have different sensor size. The PJ760V is 6.3mm, PJ660V is 4.6mm while the entry level is 3.1mm.

Maybe I should have gotten an older model with a larger sensor since all I wanted was the balanced steady shot. Got my PJ660V for $1480 in singapore.

 

[ricohflex]

My old video cams are very obsolete. Much worse than yours.

Your PJ660V has a sensor that is 7.68 square mm in area. It cost $1480. Yours come with a 12x zoom lens built in.

My friend just bought a used Canon 5D Mk2 in mint condition for $1,600.

He can use it for video.

Of course one has to have the lenses for 5D Mk2 already. Which if one needs to buy separately, cost money.

However, the Canon 5D Mk2 full frame sensor is about 864 square mm in area.

That is about 112 times the size of the sensor of the Sony HDR PJ660V. Presumably, it helps with the image quality in some small way.

Agreed that one is a specialised video camera and the other is not. Comparing apples with oranges.

The 5D Mk2 with lens set up is more bulky compared to PJ660V.

Another friend said that knowledgeable users are buying Canon 5D Mk2 and using them with Carl Zeiss Contax lenses - for video.

 

[astrocom]

I would say after having spent the money, don't let yourself down by comparing specs unless you have paying clients that demand better. Now that you have a tool in your hands, focus on the craft. Have you used other cams and did the video quality make any difference to you? Do you hav e post processing process/equipment that you feel was a letdown because of the video quality? If not thats's fine. Enjoy what you do.

I am a hobbyist and upgraded to an NX30 after by chance I got a paid assignment. The video quality was of course better but it did not make me a better videographer than when I was using a consumer video cam but I plan on improving as I use it and then upgrade again when I feel I am better and want to up the challenge.