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-   -   The thing I dislike MOST about my EX1... (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/145325-thing-i-dislike-most-about-my-ex1.html)

Hanno Klein March 19th, 2009 11:06 AM

Hi,

for me i dislike the freaky jerky zoom when you try to do a slow zoom with using a Remote Control like the Bebob EX1 or the Manfrotto EX521. We have two EX1 cameras working perfect, but our new EX1 does the jerky zoom and sony say that is normal...mmh...so this i dislike it most. And i will never buy a EX1 again without testing it before.

-Hanno

Ted OMalley March 19th, 2009 11:32 AM

Isn't it nice that nobody has said "poor image quality" even once!

Many of these issues were addressed on the EX3 - audio buttons recessed together, LCD, etc. However, the power switch is still VERY stupid.

Keith Moreau March 19th, 2009 11:35 AM

I'd love to have the expanded focus out through the external video ports, would be so much more useful for focusing.

Piotr Wozniacki March 19th, 2009 11:37 AM

Quote:

Originally Posted by Keith Moreau (Post 1030318)
I'd love to have the expanded focus out through the external video ports, would be so much more useful for focusing.

Yeah... Ideally with zebras, peaking, histogram and dof bar, too.

Andy Nickless March 19th, 2009 02:48 PM

Quote:

Originally Posted by Ted OMalley (Post 1030316)
Isn't it nice that nobody has said "poor image quality" even once!

Sorry to disagree Ted.
If you scroll up you'll see my post above.

Quote:

If you inadvertently set your iris to anything over f6.7, the image is soft to say the least.

David C. Williams March 19th, 2009 03:55 PM

Quote:

Originally Posted by Andy Nickless (Post 1024684)
OK - I'm going to cheat (and rant) a little.

Here's another thing I dislike most about the EX1 - in fact, about every video camera I've owned to date (I can't afford those interchangeable lenses and for my work I need a small camera anyway).

Sony along with all the other manufacturers fit lenses that have f-stop (iris) settings from about f1.9 to f16.

But these lenses are UNUSABLE from f8 to f16.
If you inadvertently set your iris to anything over f6.7, the image is soft to say the least.

So WHY do they all do this?
(What's the point - apart from conning the poor buyer / operator)?

They don't intentionally make it soft :) There is no lens on the planet that would help you, unless they somehow disobeyed the laws of physics.
It has to do with the optical low pass filter, the size of the sensor, and the iris. Once you stop down past around 5.6 your getting to the point where green light, the major sharpness component of vision, starts to become partially blocked. So your resolution drops.
The smaller the sensor, the tighter the optical low pass filter size, the earlier the f-stop begins to affect the resolution. It begins roughly at F4 on 1/3, F5.6 on 1/2 and F8 on 2/3.
You haven't been conned, you just weren't paying attention during high school physics :) Look up Airy Disc.

Tom Hardwick March 20th, 2009 01:32 AM

Quote:

Originally Posted by David C. Williams (Post 1030424)
It has to do with the optical low pass filter, the size of the sensor, and the iris.

Not sure about optical low pass filters but you're seeing diffraction losses coming in to play, where light rays - that should remain straight to form a sharp image - bend when they meet a sharp, hard-edged surface such as the iris blades.

So diffraction begins as soon as you start to stop down the lens and it's only the first couple of stops that removes the vignetting and internal flare that disguises the fact that diffraction has started to take hold.

My old VX2000 has iris blades that would stop down (in auto) to f/16, f/22 and even f/45 before they closed completely. For those that would ignore the silent scream for the NDs, it meant you still got correctly exposed (but very soft) footage.

So no need to rant Andy - as David says, it's the laws of optics at work.

tom.

Piotr Wozniacki March 20th, 2009 02:47 AM

Quote:

Originally Posted by David C. Williams (Post 1030424)
The smaller the sensor, the tighter the optical low pass filter size, the earlier the f-stop begins to affect the resolution. It begins roughly at F4 on 1/3, F5.6 on 1/2 and F8 on 2/3.

Interestingly, with my old good V1E diffraction effect kicked in also at F6.7-F8, even though it has 1/4" imagers (vs 1/2" of the EX1), so I'd say the EX1 becomes soft a bit too early.

David C. Williams March 20th, 2009 02:52 AM

The OLPF is where it's blocked, but that's directly correlated to sensor size. It's the narrowest point the photon has to pass through.
1/2" CMOS is roughly 7mm wide. 7/1920 @ 0.0036 or @ 3600nm per photosite. The OLPF filters out detail twice that pitch @ 7200. When the Airy Disk get bigger than the photosite, you get diffraction limiting on your resolution.
Airy Disk = 1.22 Green = 550nm - 1.22*550*5.6 F-Stop = @ 3750nm. The diameter is @ 7500nm, bigger than the OLPF and resolution loss occurs.


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