Hi

A wild guess from me is that the diameter of the optics doesn't matter so much. Think of it this way: Point your camcorder to an object which fills the screen, for example a wall of a house. The light that falls in to the camcorder from that wall is not dependant of the lens diameter. It does not become more light from the wall if the diameter is larger, the amount of light is only dependant of the source.

I guess that a larger diameter on a lens gives less optical problems within the zoom range, for example chromatic and spheric aberation, and also gives the manufacturer larger room for compensating for such problems and also build a more rugged system with higher quality. A larger diameter might reduce for light loss within the lens system though, so perhaps it does matter in some cases.

As I don't have a degree in optics this is only wild guesses as I said. :-)

Regards,

/Bo

I was hoping that a larger diameter would allow more light to hit the sensors so in low lit envorinments you are allowing more light into the censor hence less need to add gain etc.

Just a hope :)

The larger front element is often an indication of greater lens speed. Much so in in telelphotos, because there is a minimum diameter needed to give a certain maximum aperture. The formula is focal length / front optic diameter = maximum aperture. So if a 600mm lens is to have an f4 aperture that means the front optic needs to be 150mm across at the minimum.

According to the specs the Canon lens is f1.6 and the EX1 is f1.9, so barely anything in it. It could be that the Canon is constant f1.6 through the range though, and the EX1 drops to f2.8 or so at the long end? Don't know.

Steve

F-stops are for focal ratio, t-stops are for transmission. While unlikely, a certain f2 lens could allow more light than an f1.8. Sensor size is usually the most important factor in light sensitivity, so it's very likely that despite the slower f-stop, the EX1 is ultimately more sensitive. This is an issue that can only be resolved empirically.

It's not a constant-aperture lens, no. It stops down to f/2.8 at full telephoto. However that is the fastest they've ever done at the long end of the lens. The equivalent 35mm still photography field-of-view at full telephoto is almost 530mm. Canon doesn't even make an EF 500mm f/2.8. Pretty impressive, in my opinion!

Well, it is far easier to make a low f stop lens for a smaller sensor as the f stop is defined as the focal length divided by the iris diameter. For a given angle of view, a smaller sensor will require a lower focal length lens, meaning a lower f stop.

People often confuse f stop for a physical measurement, which it isn't. It isn't actually the f stop which dictates DOF either, it is the physical iris diameter. f 2.8 on a wide lens will give deep DOF whereas on a telephoto will give shallow DOF; that is because the iris diameter on the telephoto lens will be greater.

The ultimate example of iris controlling DOF is a pinhole camera, where no lens is even required, yet everything is in focus.

Not disagreeing with your post Chris, just clarifying in case people interpret it wrongly.

82mm filter is really large! A good one will set you back over $100.00. I actually had to google this to see if they made an 82mm, and they do.

Otherwise I was going to install a Pella window in front of the lens, if and when I procure camera.

Jonathan

On the lens, My contacts at Canon told me that the engineers had designed the 18x lens to mimic the typical 18x lens used by many of the 2/3" shooters of news and sports. In other words, the shooters know exactly what their tele and wide views are. If you were to remove their 2/3" from their shoulder and replace it with a 300/305, it is the exact same field of view....the wide all the way through to the tele that they are used to. Smart thinking.....

Jim Martin
Filmtools.com

I played with the 300/305 for a bit at Cine Gear. Ergonomics are similar to the XL/XH models. The rep indicated that the lens (with a healthy 29.5mm wide angle...35mm equivilant) had much less CA than the
XH-A1. This lens has HARD STOPS for ZOOM and FOCUS in the manual mode...a huge plus!
The plethora of menu adjustments should provide a large number of great in camera "looks" that can be stored on an SD card. I have always liked Canon's implementation of OIS and this camera does not disappoint in that regard.
Couple of things that didn't really thrill me:
I found it difficult to see/center the entire viewfinder image, even with the rubber eye cup folded back. When the diopter adjustment was set so that the center was sharp, the left edge was soft. This is probably just an issue with the VF on this particular camera sample, as I've never seen it on a Canon before.
No firewire port. Do services like UStream need the reliability of firewire, or will USB 2.0 suffice (given the shared bandwidth of USB ports) on a laptop? Streaming would likely be done using the 25mbs 1440x1080 mode, anyway.
All in all, a really nice camera; and that 50mb 4:2:2 codec is going to make compositing a lot easier in greenscreen work, extensive CC/grading, etc. Sure hope it will work with Vegas Pro.

Ken

Ken the files do work with Sony Vegas 9. I had no problems editing the files.

The XF300 appears to be an amazing camera, and that 4" LCD is like a gift from heaven as it replaces the poor LCD from the Sony HDV models (Z5, Z7).

The only thing Canon seem to have forgotten is a PUSH AUTO IRIS on the handgrip :(

Mark,

There is a push auto iris button on the LH side of the camera - exactly where it is easy to reach.

Bottom right of the picture (attached)

All the controls are beautifully laid out IMO. More pics (already posted) XF305

Nick.

Hi Nick yes I know, but doing the kind of ob doc work I do and having a Push-Auto-Iris on the hangrip makes life much easier.

Hopefully Canon will bring out firmware so you can assign the Push-Auto-Iris to assign button 6 which is on the handgrip for Magnification.

poor LCD?
 

Mark, why do you say "poor LCD on Z5, Z7"? The XF series has superior LCD (resolution, size) but not astronomically in comparison. Maybe you were confusing with Canon A1's LCD or older models of the other brands...

Hi Cristian, from the videos and photos of the XF300 the LCD it appears to be very bright (as well as high rez etc)

I personally find the Z5 & Z7's LCD's useless outdoors when doing run and gun etc. I know others have too.

An interesting thought Mark - we all use these cameras in such different ways.

Nick.

If I recall correctly, that test was designed to measure the relative sensitivities at 0dB gain. From that an effective ISO figure can be worked out - at 0dB. So far, so good.

That's not the same thing as "the sensitivity of the camera". For the latter you need to specify noise levels at the measurement value, and it seems that the HPX300/370 has higher noise than an EX at the same gain setting. Put another way, you can get away with using more gain on an EX than on a 300/370 for comparable quality, and that means it will have an advantage of more than 1/4 stop in low light in real usage.

He did do tests at +12db and noted that the EX was slightly lower noise.

Quote from his article "in 1080p mode the HPX370 wins the low-light battle. However, when you start pushing the gain, the Sony appears to have a cleaner gain circuit than the HPX370 does. I found the noise difference to be substantial and in the HPX370's favor at -3dB, but when both were set on +12dB it appeared that the Sony was slightly lower noise than the HPX370. Of course, I should have been trying the HPX370 on 9dB to match the Sony at 12dB; that might have equalized them out".

I get the impression that any differences will be fairly minor and so not a big deciding factor (ie much less so than form factor or codec for instance).

Steve

Yes, you are right on the outdoors usability of Sony LCD's. But you don' know how good is the Canon's LCD in practice, it's only an assumption that is better in bright conditions. We will have to wait and see.

Well, it might have "equalized them out" in terms of noise in the picture, but any gain reduction would have meant then needing more illumination on the scene for the 370 to maintain exposure parity! Whichever way you look at it, it puts the HPX370 at a disadvantage compared to the EX.

There are reports that a difference between the 300 and the 370 is that the 370 gets the noise level down by some form of electronic noise reduction. Unfortunately it comes at a price, and it seems to be an overall softening of the picture and a slight "plasticky" look. You don't get anything for nothing, and when all else is equal there is no substitute for larger chips.
In respect of chip size, then if all else is equal, a 1/2" will have a 1 stop advantage over a 1/3" camera. Whether that manifests itself as low light advantage, noise level, less need for artificial noise reduction, or a combination of the three will depend but I think it's wrong to call it "minor".

In respects of form factor then maybe the Sony PMW320 is a better comparison to Panasonics HPX370 - and that is true for such as cost, weight, size etc as well. I don't pretend to like the form factor of the EX1, but it does seem that in picture quality terms the HPX370 is beaten overall by the EX1 - despite the latter being much smaller, lighter and cheaper. I put that down fair and square to the 1/3" v 1/2" issue.

"it does seem that in picture quality terms the HPX370 is beaten overall by the EX1" Does it? What's that impression based on? Not saying you're wrong, just haven't seen any evidence that clearly shows that.

"if all else is equal, a 1/2" will have a 1 stop advantage over a 1/3" camera" That's definitely a relevant point - all else is rarely equal, and as Barry Green's tests showed, there's actually very little in it. Not saying that I trust Barry Green more than anyone else, but I do get the feeling he's a fair commentator, and above all his is the only comparison I've seen!

"There are reports that a difference between the 300 and the 370 is that the 370 gets the noise level down by some form of electronic noise reduction" The only suggestion I've seen of that has been by me!!! I mentioned that in response to Andy Shipside's comparison but got no response. It certainly did seem to me,as you say, that the image was less noisy but a fair bit softer - just as you'd get if you put a still through Noise Ninja.

I really feel that a lot of people discount 1/3" needlessly. Even the depth of field argument is often not that big a deal. For example for most documentary stuff any shot you'd do at f4 on an EX1 will look the same on a 1/3" chip camera if you set it f2.8. It's only for drama focus pulls/shallow dof that it might be a bit of an issue IMO.

I think IF you've got a lens that you are happy with from f1.8 you've got a useable range of f1.8-f5.6 before you'll get any noticeable diffraction effects, so as long as you've got enough NDs to allow those wide apertures in your lighting situation then there's not a problem.

Just my opinions though, I fully respect anyone's opinions and disagreements!

Steve

By "all else equal" I was really thinking of such factors as CCD or CMOS? Total no of pixels on chip? Do the chips have microlenses? It's very difficult for manufacturers to defy the laws of physics as they apply to silicon - it's a bit like aircraft design, manufacturers put the numbers into computers and tend to get the same results, which is why all airliners tend to look much more similar now than they used to.

In this case, both the EX and the 300/370 are CMOS and 1920x1080. I believe the EX chips use microlenses, the 300/370 doesn't, so combined with the chip size difference the EX would be expected to have more than one stop intrinsic difference.

Now maybe Panasonic have access to alien technology which would explain why Barrys results don't match expectations. An alternative might be down to lineup - quite a few factors could affect the noise level, and it's possible to degrade certain performance factors to favour noise. Another alternative is if active noise reduction is used, which is down to the same thing - degrading other aspects of image quality in favour of reducing noise. So in this case "all else is not equal" benefits the HPX370 in one regard, diminishes it in another.
It used to be a case of going for 1/3" because you couldn't afford cameras with bigger chips. A general acceptance that 1/2" was better, 2/3" better still, but hey! I can't afford them and 1/3" is good enough for me. Alternatively size/weight was a crucial factor so 1/3" it had to be.

The EX changed all that by giving 1/2" chips in a camera at a price/size/weight that previously had been that for 1/3". It's ceases to be a case of quality versus price - it's one of why settle for less if you can get better for the same price?

That all seems reasonable David, you may well be right. But until you've done tests it's just supposition as to which is better. Barry's done that and I have no reason to doubt him.
Steve

This is all relatively moot, because the fact is, all things are not equal. Sensor size (in terms of 1/3 vs 1/2) is a tiny tiny part of the whole pie. Here's the difference between 1/2" (pink) & 1/3" (yellow) sensors:
http://i882.photobucket.com/albums/a...at115220AM.png
At that level, lens quality, codec, processing power & implementation and a host of other factors play a much more crucial role in determining overall IQ - and that's why Panny's HPX300's & 370's have been so successful at securing a majority market share in broadcast television vs any of the Sony XDCAM line (ex1, ex3 & even pmw350).

If bigger is always better, Sony should be winning the game. But they're not, and there's a reason for that.

I was able to use the Canon XF305 outside in bright light. The LCD performed very very well, although I always prefer to use a hoodman or the like. However, it is, without question, the best LCD on any camera that I've had the pleasure of using. It really is a step up.

The fact is that in terms of area a 1/2" sensor is twice as big as a 1/3" sensor. For chips of each size, each 1920x1080, that means each individual photosite will be more than twice as big in the 1/2" chip case. (It'll be more than twice because it's reasonable to assume the inter-site border will be the same in each case, hence takes up less percentage wise in the 1/2" case.) That means twice the light gathering power/photosite, and therefore an inherent advantage of at least a stop if the chips are otherwise the same.

No matter how good or bad a manufacturer may make a camera with 1/3" chips, the same manufacturer making the same camera with 1/2" chips will inevitably be better - a lot better. You only have to compare Sonys EX with Sonys NX5. (They keep the photosite area the same, but the NX5 has about 1 megapixels/chip compared to double that for the EX.)

Hardly surprisingly, manufacturers who only sell 1/3" designs tend to disagree with that - at least in public. It's marketing, not science.

Oh you make me happy Brian on the confirmation of the LCD. Im going to 100% buy this beasty XF300.
The EX1 is just too awkward to use hand held days on end.

I will mainly shoot in 35mbs and for special occasions i.e very low light ive got the option to go 50mbs!!

Im still praying Canon will bring out some firmware to allow Push-Auto-Iris on the handgrip hehee :)

The DOF argument goes in favor of the EX-1. But the LCD w/ waveform monitor and vectorscope is going to make composing a good, well lit shot quite a bit easier on the Canon.

I wonder why Canon didn't go with 1/2" chips for their 300 / 305 models as it would of pleased more people for sure. I used an Canon L1 in Hi8 way back in 1991 that had a single 1/2" sensor that was better in low light than the XL1 or the XLH1 that I used since for wildlife filming.

As handy as this camera will be to pack around, the lack of lens power won't cut it for most wildlife shooting I do. I'm hoping for their interchangeable model soon ( anyone have an idea when? ), maybe they will surprise us with 1/2" chips. In the meantime I'll keep using my XLH1 that has never missed a beat.

Leon Lorenz
Canadian Wildlife Productions: Grizzly Bears, Bighorm Sheep in Alberta & BC Rockies DVD Videos

Well, maybe because 1/3" chip sensor allows long range zoom for an affordable price. As a wildlife cinematographer too, I prefer a 1/3"chip with a 18x zoom than a 1/3" chip with a 14x zoom.
Of course, an interchangeable lens would have been even better, but I bet that, if Canon make one, it won't have a 1/2"chip, because Canon wouldn't want to redesign the zoom.
I also keep my XLH1 with a NanoFlash and it rocks!

Agreed Ronan, and it's not just lens price it's also the size. A 100-300 f4 Sigma is a lot more compact than a 200-600 lens that would be the equivalent on a 2./3" sensor. Bigger lens, so bigger tripod too - before you know it you'll be in hospital with a broken back!
And with that in mind I'd suggest that the wildlife community should be crossing their fingers that Canon don't put 1/2" chips in an interchangeable lens model.
Steve

I think you're absolutely right about this. However, the same argument doesn't work when comparing cameras from separate manufacturers because of how many variables are involved in ultimate performance. That's why any argument stating that an EX1 is better than a XF300 because the EX1 simply because it has a marginally larger chip size just doesn't hold water. Truly, both cameras have pros and cons over each other - testing has shown that the EX1 has about a 1 stop light advantage over over the XF series, naturally due to it's larger sensor and photosites. A one stop light advantage does not necessarily make the EX1 a superior camera, unless all you care about is low-light ability (some may argue a shallower DOF feature of the EX series as well, but in my experience, there is no easily perceptible difference in DOF between 1/3" & 1/2"). Early images suggest better dynamic range & more resolution in the XF line (and certainly more color information via 4:2:2 out of the box). There's a lot of factors to consider here.

A lot of people/productions have very different needs when it comes to a video camera. In this day and age where nearly all cameras are way past "good enough", bigger is better regardless of all else is a failed argument.

Going back to the original poster's question about the sales guy pushing the Sony over the Canon b/c of the sensor size - well, from my experience working in sales, there's one simple reason for this: that sales guy can sell a Sony right now, today. He can't sell the Canon. Any decent salesman will always push a product he can sell immediately over one he can't sell for the next month or two. Which is just one of the reasons why I think it's very dangerous to take buying advice from a salesman (but that's getting into a whole other can of worms)!

Firstly, I wouldn't call the difference "marginal" - 1/2" chips are twice the area of 1/3", and the practical difference is more owing to the likelihood of the inter-photosite boundaries being a lower percentage of the total in the bigger chip case.

In principle you're absolutely correct, you can't say that any camera is necessarily better than another purely because of chip size. BUT, for two cameras with the same underlying technologies (no of pixels, CMOS/CCD, 3 chip/1 chip etc) the manufacturers of the larger chip version are starting off with a huge advantage in design terms, and whilst desirable, I don't think the 50Mbs codec will be anything like enough in itself to make up the difference. Whether Canon can pull anything else out of the bag remains to be seen - it's not impossible, but I'll believe it when I see it.

Whatever happens in practice, however good the XF300 turns out to be, there's no getting away from the fact that it would have been far better with 1/2" chips. If I'd heard that, it would be my clear expectation that we'd have a likely "EX1 killer", as it is we'll have to wait and see......

I have to agree with David. All things being equal the camera with 1/2" sensors should perform better in low light than a 1/3'' camera. Also wouldn't the larger sensor camera have a larger subject size at the same lens power? This shoud be a big plus for seeing and keeping fast moving small wildlife ( like flying birds ) in your viewfinder easier. I believe if Canon made a 1/2"sensor camera or larger they would have a huge market, I for one would buy it in a heartbeat. I looked at Sony's EX3 about a year ago and it looked very cheaply made compared to the Canon XLH1 which I now use.

Leon Lorenz
Canadian Wildlife Productions: Grizzly Bears, Bighorm Sheep in Alberta & BC Rockies DVD Videos

No, other way around. A smaller sensor will give you a larger subject in the frame @ same 'lens power.'

In regards to Canon pulling some other magic out of the bag, I will say this: When I was playing with the XF305 at Cinegear, I zoomed all the way in (18x), pointed at some high contrast vertical lines, and whip panned away at various speeds. I couldn't see any rolling cmos skew in the LCD. I'm sure there's some there, but compared to what I'm accustomed to seeing in the HPX300 & and the EX1/3 - massive difference. i don't know what they're doing, and i haven't heard a whisper of 'global shutter,' but I'm just saying there seemed to be far less rolling shutter than any other professional cmos camera I've ever used.

Also, I'm not convinced it's an EX1 killer - in fact, I don't think it is. But I would put it on par, as the EX1 certainly isn't an XF killer. And I can certainly see why some would choose it over the EX1.

another compare video and some more:

YouTube - CANON XF300 ?SONY XDCAM PVW EX-1 test.wmv

http://www.youtube.com/user/2009keiko#p/u

not mine, etc

I have borrowed an XF300 for a special project and got the chance to make a very quick comparison with the EX1 at normal gain settings. My colleague's exposure seems to be a fraction lower than mine, so I have lifted the EX gamma by 15% for the split screen shot. Aperture was f5.6 on both cameras, data rate at maximum and colour at defaults. From memory the Sony gain was minimum and XF300 was at -3dB.

The XF300 was very noticeably sharper at 1080 and there is none of the colour smearing that is obvious on the EX1 in the leaves and the grass behind the car.


I am very happy to upload the MXF file from the Canon for anyone interested, but my colleague requested that the EX clip is not put online.

Better than adding bulky downloads of static clips - here are the two full screen grabs at max quality jpeg for comparison:

The EX1 is the darker clip, the XF300 lighter - both are untouched grabs from the original camera files.

Nick.

Wow, that's pretty impressive.
I wonder how much is due to Detail settings? At f5.6 you'd expect both lenses to be pretty decent so that shouldn't make a massive difference I wouldn't have thought.
I'm quite surprised at how much better it does look.
Steve

Steve,

The camera was used on default settings (no CP set), so detail was at the default of zero (range -8 to 8). Time has been short, so I have not been able to investigate all the CP settings, but I understand that as a departure from previous cameras, some of the settings represent 'standards' removing some of the need to create custom looks.

Nick.

The road shows a lot more detail with the Canon. Would be interesting to see the same scene at wide open or tele or both and the EX with a Nano & 50mbps.

I would also be interested to see a DOF comparison between the two just to know for sure what difference there may be.