Hi Def Shimmering

[Black Lab]

I Googled "CMOS vs CCD" and found an article with the following being the summary:

CMOS imagers offer superior integration, power dissipation and system size at the expense of image quality (particularly in low light) and flexibility. They are the technology of choice for high-volume, space-constrained applications where image quality requirements are low. This makes them a natural fit for security cameras, PC videoconferencing, wireless handheld device videoconferencing, bar-code scanners, fax machines, consumer scanners, toys, biometrics and some automotive invehicle uses.
CCDs offer superior image quality and flexibility at the expense of system size. They remain the most suitable technology for high-end imaging applications, such as digital photography, broadcast television, high-performance industrial imaging, and most scientific and medical
applications. Furthermore, flexibility means users can achieve greater system differentiation with CCDs than with CMOS imagers.
Sustainable cost between the two technologies is approximately equal. This is a major contradiction to the traditional marketing pitch of virtually all of the solely CMOS imager companies.

Since I do a lot of work with fast panning I guess I will look for camcorders with CCD sensors.

[kw]

I'm happy with my cmos sensor HV20 Canon. If there is shimmering or cmos rolling shutter problem (can't say I've experienced that yet even with my shaky handheld panning) that it's no worse than the panning one gets from a Hollywood movie!

[kw]

I forgot to mention that perhaps the shimmering is more of a problem on a PAL camera vs NTSC since it's only running 25fps anyway vs 30. Just a thought.

[Zippy]

Hi guys:

The arguments of CCD vs. CMOS are not quite as simple as that - it's like saying that Subaru make better cars than Ford. You have to compare model with model, and weigh up the features that are important to you.

And the "shimmering" effect is not necessarily an effect of a rolling shutter, although often this can be the case, and would appear to be in the example. It can, amongst other things also be due to compression artifacts caused by the pre-emptive encoding.

As a very rough rule of thumb, yes, CMOS sensors are more prone to black-level noise - i.e. they go all noisy in low light, but the similar effect can also be seen on CCD sensors. As a passing matter of interest (?) I have just disposed of a Fuji CCD still camera (s9600) because I was appauled by the level of CCD noise.

There is a marketing hype that many people have fallen for (especially in the stills market) that more pixels is better. This is not always the case. The physical size of the sensor is a major factor too. One of the things that has happened over the last few years, especially in the consumer level market, is that manufacturers have been cramming more and more pixels onto pieces of silicon of the same size, thus reducing the effective size of each pixel. As a rough rule-of-thumb, the smaller the charge well on the CCD (or the equivalent for CMOS technology) the less dynamic range it will have, and the greater susceptibility to (especially black-level) noise.

My little panasonic SD1 has 3 1/6th inch sensors, and black-level noise is very noticeable in low light ... a bit of a pain as I do a lot of underground video work, but at least the camera comes in at a sensible budget. I've had a brief encounter with some guys who work for a Uk animation studio. The stills camera we were looking at had a 35mm peltier cooled CCD sensor - but was "only" 8MP. Loadsa money

Yes, if you're after super-duper quality for fast moving subjects a CCD sensor with a glocal shutter will probably be what you're after. Now then... where's that elusive lottery win

Seriously though, the tricky bit (in my humble opinion) is actually making sensible comparisons between cameras. When I bought my SD1, I went to loads of shops - most assistants didn't know how to turn the thing on, few shops had batteries charged, and none were representative of the conditions I film in. And reviewing footage on a 3" TFT doesn;t actually give you much indication of the true quality of the shots. Reading reviews helps, but it's no substitute for actually using the beast in question!

Hope this helps

Zippy!

[Zippy]

... and just to add some justification to my last post:

http://www.dalsa.com/mv/knowledge/CCD_vs_CMOS.aspx

Zippy!

[Black Lab]

Of course I would compare features of the different cams I am interested in. But this shimmering, or rolling shutter, seems to be very prevalent in CMOS cams, so that is a definite deal breaker for me.

And by the way Zippy, that website that you linked is exactly where I obtained the CMOS vs CCD quote above.

[2Dogs]

Seriously though, the tricky bit (in my humble opinion) is actually making sensible comparisons between cameras. When I bought my SD1, I went to loads of shops - most assistants didn't know how to turn the thing on, few shops had batteries charged, and none were representative of the conditions I film in. And reviewing footage on a 3" TFT doesn't actually give you much indication of the true quality of the shots. Reading reviews helps, but it's no substitute for actually using the beast in question!

Boy, you aren't kidding! It just amazes me that digital cameras and camcorders are sold in dimly lit areas, (usually by fluorescent lighting) with sales staff that know very little. I've found myself going into my local big box stores armed not only with an SDHC card but also at times my laptop and USB and Firewire cables, and even a Mini-DV tape. It generally creates some consternation with the sales staff, but I've been able to get sample clips from various cameras and camcorders. It's sad that stores cater only to the lowest level of buyer, whom they expect to buy something without trying it out. I could be even more hard-nosed, of course, and buy something with the express intent of trying it out and then returning it - but I feel that's not really ethical.

Mind you, Zippy, if you started using fluorescent lights in your caving expeditions, the store lighting might approximate to a very good replication of your subterranean exploits!

[Zippy]

Hi all...

And by the way Zippy, that website that you linked is exactly where I obtained the CMOS vs CCD quote above

I though it must have been, but try as I might, I couldn't spot the exact quote you'd picked out!! We've used Dalsa cameras at work - they're excellent (although not necessarily what you'd want for your home movies).

Mind you, Zippy, if you started using fluorescent lights in your caving expeditions, the store lighting might approximate to a very good replication of your subterranean exploits!

We already have it covered! http://www.ledcavinglamp.co.uk

I could be even more hard-nosed, of course, and buy something with the express intent of trying it out and then returning it - but I feel that's not really ethical.

Now there's an idea Do you think they'd notice if the camera got returned all covered in mud & filth?



Zippy!

[Black Lab]

I though it must have been, but try as I might, I couldn't spot the exact quote you'd picked out!!

FYI - It was one of the links on the right column, which opened a pdf.