I myself along with many others are trying to make a decision in regards to this cam. $3000 may be nothing to you, but its $5000 +tax in my country, + matte box + batteries + filters ect... . Or put in another way a lot of money for someone who doesn't get paid to use ultra high end cameras all day.

We all value your input as you are possibly the most qualified person who has ever commented on this cam at any length. Some of the things you have said, the DVX comparison for example, are 180 degrees from some others. We all here have a high degree of enthusiasm for this cam, so we tend to question everything. Usually with no disrespect intended.
Ken

I don't recall saying small sensors were capable of superior overall performance. I simply said that sensor size did not determine DOF. This fact is not controversial but it is often misunderstood by non-technical types.

A very good discussion of lenses, including DOF, can be found here (http://www.photo.net/learn/optics/lensTutorial). You will see in the DOF equations that sensor size of a format is never mentioned. This is intuitively obvious, of course, and fully supports my claim.

Nevertheless, the claim that was made was that both cameras in question had identical sensor sizes, yet one exhibited significantly different DOF than the other. If that is true, then there are only three explanations: (1) the observer is mistaken, (2) f-stop and focal length, and therefore physical aperture, were not held constant, or (3) there is something wrong with the DVX100 lens. The third option is unlikely. More likely it was a testing error or a consequence of the substantial difference in video format. Generally speaking, the higher resolution format would be expected to give less perceived DOF, the opposite of what was reported.

On a separate issue, I found this quote unusual:
Bottom line is, the DVX100's full 480P vertical resolution is comparable to the HD10's HDV 720P resolution.
Sure they're comparable but the comparison is unfavorable! In order to accept that the DVX100 provides similar or better vertical resolution (as was implied) you would have to accept that the JVC is a tremendous underperformer for 720p (roughly 1/2 to 2/3 the potential of the format). I doubt that seriously. It would be pretty bad if the JVC couldn't resolve better than 360x240 lines in 1280x720 pixels.

Gentlemen,

If I have to do any more editing to this thread, I'll simply lock it and be done with it. Please retain the highest degree of mutual respect and civility and courteousness at all times. If you see something rude, don't bother responding to it because it won't last very long (flames are always edited out of dvinfo.net).

For Craig:

Just because that photo.net article doesn't mention sensor size, doesn't discount the fact that sensor size *does indeed* impact DoF. Once again, please see Jeff Donald's Ultimate Depth-of-Field Skinny (http://www.dvinfo.net/articles/optics/dofskinny.php). The man has been teaching optical science for many years and his article spells out very well the factors which determine or alter DoF (including CCD size as well as focal length). Or, see this page on photo.net (http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=001h5r): "larger sensors have less depth-of-field." Hope this helps,

Jon,

Did you turn the TELE MACRO setting to ON (default OFF) on the HD10U before shooting the samples we got from Chris?

Originally posted by Chris Hurd :
There is some serious misinformation in this thread concerning DoF (depth-of-field). CCD size as well as focal length do have an impact on DOF, it is not simply a function of magnification and focal length. For more information about how CCD size and focal length can impact DoF, see our Ultimate Depth-of-Field Skinny (http://www.dvinfo.net/articles/optics/dofskinny.php), part of our Optical Science series by instructor Jeff Donald.

Sorry, Chris, but you are incorrect. I read through Jeff's article briefly and it looks OK, but I prefer this article (http://www.photo.net/learn/optics/lensTutorial) since it is far more complete. In any event, focal length only effects magnification (target size in Jeff's article) and the proportion of front-to-back DOF. Magnification is already mentioned, and front versus back doesn't matter in the discussion of total DOF. Jeff's article largely supports my claims.

The fact is that "target size" changes somewhat between formats for identical perspectives, but at higher magnifications it is offset by the lowered acceptable diffraction tolerance. Larger sensors are actually capable of better DOF in macro than smaller ones. I suspect people here don't concern thenselves with macro too much, but macro DOF issues are more difficult (i.e. intractable) than wide or normal perspectives.

The real concern, and the one Jeff makes an example of, is trying to restrict DOF. Prosumer devices have integral lenses that place limits on the range of DOF they can achieve. This is a practical concern and does not reflect what any sensor is capable of. It's a mistake to extrapolate an experience with one or several specific cameras into a generalization of any camera with that sensor size, yet that's just what Jon has done.

Larger sensors make it easier to achieve limited DOF not because the sensors have inherent DOF qualities, but because they allow the use of lenses that are more appropriate for that kind of shooting. This is a practical issue, not a technical one.

With regards to the two stills:
First of all, I would have expected the JVC frame to be 1280 across,not 720.
To compare detail of a lower spacial resolution image with a higher one, the lower one is typically resized up to the bigger ones size. It's safer to upsize, because you are not crushing out possible detail that way.
The older clips posted were done the right way, the DXV footage was sized up to the 1280 size of the JVC.
Naturally, the DV diehards hate that type of test, as DV looks totally out of focus that way. That's life. When up do a film out, it all gets sized up to academy or whatever, so no biggie.

The DOF is very different, OK, got that.

The HD10 image still looks like it shows more detail in the logo on the green bottle, and the sunglasses case. Just a tad. Hard to tell at 'web cam' resolution (720), it's just too mosaic-ed in the details.

As far as the picture rights and posting stuff, too bad you didn't have a few seconds to swing the camera 'off set' and at a road case or grip truck, or a porta potty, to eliminate the rights issue. I understand the situation was probably pretty stressful anyhow, you were probably pushing peoples patience with the 'toy' camera there anyway.

If anyone is in LA and would like to shoot some tests, I have a HD10 to test with. Heck, I can shoot some 35mm movie film too, which I'll scan as 2K Cineon format, just to see what that looks like, of the exact same scene. Some of the new Kodak stock as pretty much no grain, at 2K res. ( 2048 x 1556 pixels )
-Les

The size of the sensor has an effect on Circle of Confusion (CoC). CoC is a factor in DOF. Magnification is a part of DOF as DOF is determined by distance to subject and the focal length of the lens.

Craig's analysis of the observed differences is probably correct. We are dealing with a very subjective media. The five factors that determine DOF include the subjective nature of personal observation (see factor E in the article (http://www.dvinfo.net/articles/optics/dofskinny.php)). The critical analysis that many of you are looking for need to be observed under a more controlled situation. Don't make inference's from personal observations that are not your own. It's an argument that is never won.

<<<-- Originally posted by Chris Hurd :
For Craig:

Just because that photo.net article doesn't mention sensor size, doesn't discount the fact that sensor size *does indeed* impact DoF. Once again, please see Jeff Donald's Ultimate Depth-of-Field Skinny (http://www.dvinfo.net/articles/optics/dofskinny.php). The man has been teaching optical science for many years and his article spells out very well the factors which determine or alter DoF (including CCD size as well as focal length). Or, see this page on photo.net (http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=001h5r): "larger sensors have less depth-of-field." Hope this helps, -->>>

The photo.net article is definitive as far as I know. I'd be curious to know if Jeff thinks it is incorrect. At first glance, I'd didn't see anything in Jeff's article inconsistent with it, and I'd be curious to know if Jeff disagrees with it.

The Kevin Borden reference just demonstrates than many people believe sensor sizes have inherent DOF field properties. They don't. They just record the image rendered on them. The size does determine the required magnification for a given perspective, but that is all.

P.S.

Twice now I've been caught composing while someone else was posting. This time by Jeff.

I think there is some difficulty with terminology between here and the still folks (although the optics work the same). Sometimes terminology alone can cause big arguments.

Sensor size has nothing to do with DOF. Craig's right.

Think about it: the lens resolves the image and then projects it onto a surface: it doesn't know nor care what that surface is. It could be a 1/3" CCD, or a 2/3" CCD, or a piece of film, or a piece of ground glass, or a blank wall, it doesn't matter. All DOF is resolved and settled within the lens. The sensor just records what the lens projects.

The CoC is related to the amount of magnification an image will undergo. The image (as projected by the lens) will be identical either way. The circle of confusion is just a guideline to adhere to when thinking about how much magnification you're going to put the image under.

Here's another way to look at it: put a Nikon lens on a 35mm movie camera, and shoot a frame of film with it. Then put that same lens, in the exact same position, on a Bealieu Super 8mm camera with Nikon adapter. Shoot the same scene. Then take the 35mm film frame, and cut out the central 6mm x 4mm area, and compare it to the Super8 frame. THEY WILL BE IDENTICAL. Absolutely grain-for-grain identical. Blow them up to the same size, and they will look identical.

Finally, regarding Jon's two shots: I have no doubt whatsoever that the JVC had a smaller aperture than the DVX did. That is, quite simply, the only rational explanation for the differences observed in these shots. Especially when you consider that the DVX would have needed to be zoomed out *wider* than the JVC in order to capture the same framing and field of view (due to the 4:3 DVX vs. the 16:9 JVC).

Sensor size has nothing to do with DOF.

Until you print it, project it or transmit it to a TV. Then differences in CoC, as a variable of film size, chip size etc., will have an effect on DOF.

Since this is a video forum and people's work will be viewed on a TV or projection screen (magnified), it is misleading to ignore CoC and it's impact.

Originally posted by Jeff Donald :
Until you print it, project it or transmit it to a TV. Then differences in CoC, as a variable of film size, chip size etc., will have an effect on DOF.

Since this is a video forum and people's work will be viewed on a TV or projection screen (magnified), it is misleading to ignore CoC and it's impact.

Assuming an identical projected size, the CoC on the imager will be smaller on the smaller imager in proportion to its reduced size. That reduction means that DOF is reduced, but that reduction is offset by the reduced magnification required of the optics to achieve the same perspective. The reduced sensor size means that diffraction effects must be similarly reduced. Since DOF is inversely proportional to the square of magnification and CoC and allowable diffraction are proportional to sensor size, the end result is a wash (except at high mags where effective aperture is different from physical). At low mags and identical physical apertures, the smaller sensor will have larger DOF in proportion to the ratio of sizes.

Craig, we're in agreement except I've never been to a theatre that projects 35mm film to a 32 inch diagonal. The Inverse Square Law does play a role, as you point out. If you see factor D in my article, the viewing distance (or size of screen, print etc.) has an apparent effect on DOF.

At low mags and identical physical apertures, the smaller sensor will have better DOF in proportion to the ratio of sizes.

If by better you mean a larger DOF, we're in agreement.

I suppose a target viewing size could be unreasonable for one format and not another, but you wouldn't need to compare their DOF performance then. If you wish to compare DOF characteristics of different formats, you must choose a common final viewing standard or the comparison won't make sense. You are correct, viewing angle/distance effects DOF but it does so equally on both formats in the comparison.

I changed "better" to "larger".

Hi Craig,

I notice that you own a JVC HD1 in addition to your Sony VX2000?

Do you ever shoot 16:9 on your VX2000? How are you incorporating the HD1 into your work? Will you be considering taking the HD1 underwater with you? Also, would you possibly have any spare time to produce a few side-by-side comparison images between the VX2000 and the HD1? They don't have to be swan song images or such, just a few side-by-sdie examples of any type of subject will do. I thought it would be helpful to get a tangible report of your experiences with the HD1 so far.

I understand if your schedule does not allow for this, but would certainly love to hear your feedback.

- don

you must choose a common final viewing standard or the comparison won't make sense.

And therein lies the problem with discussions of DOF and personal observations collected in an unscientific manner.

No standards were established at the beginning of the comparisons of the DVX100 and HD10. We must rely on Jon's experience and professionalism to convey his impressions of the cameras performance.

So... back to the DOF differing pics that Jon posted: Can the HD10 come close to the short DOF the DVX got in that shot?
I wonder if ND could shorten it that much?

For the academic types: A picture is worth 10^3 words. It's fun to chat about images, but posts of images and viewing them are where it's at.
"Where's the beef?" comes to mind.

-Les

The two cameras in question, if operated identically and are focused on the same subject, and the subject is of similar proportion, will produce identical DOF.

Define "operated identically".

The JVC has no readout of it's aperture setting, that complicates matters. I suppose you could ND the JVC until you see a drop in viewfinder exposure seen, and then assume it is at the widest f stop it can do. Then you have to assume that aperture is what JVC states as the minimum aperture. Too many assumptions for me.
In Jons sample pics, the JVC obviously had enough light to stop down. Says something about LUX ratings, but I don't want to open than can of worms either!
-Les


<<<-- Originally posted by Jeff Donald : The two cameras in question, if operated identically and are focused on the same subject, and the subject is of similar proportion, will produce identical DOF. -->>>

Les, operated identically is self explanatory.. If the operation of the camera requires too many assumptions for you to be comfortable, then the JVC is probably not the camera for you, at this time.

Ergonomics and features are just as important as picture quality in determining the suitability of a camera to an individual operator. Let alone suitability towards specific projects. If you have a project that requires the limits of shallow DOF then the HD10 may be a less desirable camera. Not because it cannot deliver the limits if it's range of DOF. But, because it is obviously more difficult to accurately reduce the cameras aperture setting. Combine this with the inability to reproduce exact settings i.e. no manual controls, and you have a camera that won't be suitable for everyones needs.

Whew, I'm sorry I opened a can of worms on this subject! My apologies to all, and thanks to Chris H. for stepping in!

heath

Jeff, please explain how the DOF can be held constant on both cameras , even if you operate them identically, if the effective ISO speed of the cameras CCD's are different. You must mean using ND's to control the f-stop , that's all I wanted to clarify.
Are you sure the lowest F number of the two cams in question is the same?
If not, you may not get the same DOF, ( no matter what ND ) I hope you know that!
For most casual users, fumbling with ND's is a hassle, but we do it to coax the consumer grade cams to do what we want.
I own the HD10. I know it's limitations, but it is the camera for me at this time, because it resolves closer to movie film, which I am used to working with digitally at 2 to 3K res starting in 1988.
I always wished for more resolution, and when I saw that in this JVC , I was sold.
No more 'web cam' DV res for me. Hallelujah!
-Les

Did some digging.
The Panasonic lens is f1.6
The JVC lens is f1.8.
The JVC's lowest possible DOF is higher than the DVX.

Les, the problem with most discussions of DOF is the theoretical aspects measured by formulas vs. the observed aspects of viewers. Using standard DOF calculators, the difference between F1.6 and F1.8 is pretty small at most distances and focal lengths. A subject distance of 15 feet and focal length of 10mm, the difference in DOF is just over 2 feet. Because of the subjective nature of individual viewing, the difference in DOF may not be visually apparent to most viewers.

I agree that multiple ND filters is not ideal. There are several operational features that are either missing or inconvenient in their use. This will lead many potential users to wait for the next generation. I can understand pioneers, like yourself, purchasing the HD10. It is a unique camera that offers many great features, but will challenge many, in it's more complicated operation.

Originally posted by Don Berube :

Hi Craig,

I notice that you own a JVC HD1 in addition to your Sony VX2000?

Do you ever shoot 16:9 on your VX2000? How are you incorporating the HD1 into your work? Will you be considering taking the HD1 underwater with you? Also, would you possibly have any spare time to produce a few side-by-side comparison images between the VX2000 and the HD1? They don't have to be swan song images or such, just a few side-by-sdie examples of any type of subject will do. I thought it would be helpful to get a tangible report of your experiences with the HD1 so far.

I understand if your schedule does not allow for this, but would certainly love to hear your feedback.

- don


I have not used the VX-2000 in 16:9 mode nor tried to combine footage from the two cameras.

I've worked with Gates to develop the JVC housing (which is now in early production). I haven't received my housing, though. I intend to use it mainly underwater but my first real underwater test won't be until February. Until then it will be pool tests only.

Don't use the VX2000 (or XL-1s) in 16:9 mode, the chips aren't powerful enough.

heath

Hi Heath,

I know this, I used to own a few VX2000's years ago.

I was referring to the VX2000 as it is one of the camcorders that Craig currently owns and utilizes in his work, aside from his newly-acquired HD1. Since there are a great deal of readers who are currently using VX2000's and similiar cameras, and since many readers are now interested in the "next-generation" of HDV camcorders which will by default generate 16:9 - thought it would be a nice example of what they can expect to experience when they inevitably start shooting in HDV. (>yikes< that was a l-o-n-g sentence!)

To clarify, the built-in electronically-interpolated 16:9 Mode from cameras that do not utilize true 16:9 chips is best used for small-frame video playback such as streaming video, multimedia presos, home video, etc. As Heath implies, "faux 16:9" is not quite good enough for full-frame professional broadcast applications such as television or DV filmmaking intended for the large screen.

However, it has been well documented that the 16:9 techniques implemented on the Panasonic DVX100, due to it's enhanced resolution and sharpness, is much more useable than most other DV handycams. I even used it on a recent 24P DV short I shot and was very happy with the results, all things considered. The new DVX100a promises to produce even better "faux 16:9".

- don

<<<-- Originally posted by Les Dit : Did some digging.
The Panasonic lens is f1.6
The JVC lens is f1.8.
The JVC's lowest possible DOF is higher than the DVX. -->>>

Well, yeah, but...

... what is the JVC's minimum aperture at full telephoto? The DVX's lens is not constant-aperture... you only get f/1.6 at the wide end (where the focal length means you're pretty much going to get infinite DOF anyway). At full telephoto the max you can get is f/2.8

I can't figure what the JVC is -- is it f/1.8 at the wide end, and f/1.9 at the tele? If so, combined with its maximum tele of 52mm (vs. the DVX's 45mm) the JVC should be able to deliver a shallower DOF than the DVX.

Barry,
I read that the JVC is constant throughout it's zoom range.
-Les

Great write-up, John. To contrast with your vast experience, I'm a bit of a wanna-be, and got time to see the HD10 in an all day demo (HD Roadshow, sponsored by Videography Mag/JVC) and training session, the day before the Gov't Video Expo last week in D.C..

Your comments about narrow range and easy wash-outs were also evident to us, but the speaker had a pat answer type phrase, each time we came to issues such as this: "Remember folks, this is a $3,000 HD camera". His way of saying, I guess, that a $3k camera will have many limitation compared to the "industry standard" cameras, but "look how much you get" for 3k.

I thought the colors were quite clean/clear, and I the reds, well, they were red, and NO bleed. I know we're gonna get one of these for our little shop, but plan to use it primarily in SD mode, since we have experience there, and probably can't afford the storage space for HD projects, just yet.

Just my thoughts. Great forum you guys have here,

Thanks, Jerry! We try to keep it friendly and informative!

heath