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(MPG4) Sanyo Xacti (all models)
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Old September 13th, 2006, 05:18 PM   #1
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Focus Issues?

I've got an issue with the focus of my HD1 at long distances, and wanted to see what other people thought prior to really digging into the problem.

The basic problem is that the camera never seems to have sharp focus for distant objects (down to at least 40m, as detailed below), with optically sharp details spilling over many pixels in 5MP mode. This happens regardless of the focus method. However at close distances (~10 cm) the sharpness is fine. I'm going to try to do some more tests to fill in the middle there and narrow down the problem, but I'd sure appreciate any input!

Here are the details I have so far:
I originally noticed a lack of sharpness in the high-contrast details of buildings at around ~200m, which I was shooting at the widest zoom setting. It's very noticeable in still (5MP) shooting, but I'd swear I'd first noticed it in HD video too. So I pulled out my 6MP still point-and-shoot camera for comparison, and was shocked at the difference in resolving power. On the HD1 I've tried various methods to focus it, including manual (set at different distances), auto, and the "zoom and lock" method suggested on this forum. I've tried stopping it down to the maximum f#. I've got the stabilization off, and am shooting from a stable tripod. I've seen this effect so far down to ~40m, and hope to try more later. Sharpness is "Normal" on the HD1, 5M-H mode, and ISO is auto (though I'd plan to play with this).

The blur looks to be a couple of pixels wide, and seems to show more on narrower objects.

As another test, I did about the same thing using a book at ~10 cm as the resolution target, and both cameras showed nice sharp edges, with ~1 pixel resolution.

Anyone have any experience like this? I'll post more when I've had a chance to do more tests.
James Butler is offline  
Old September 13th, 2006, 08:27 PM   #2
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HD1 focus issues

James Butler;

Your description of distant focus issues with your HD1 are identical to my assessment of the HD1. I assumed the cause of the focus problem to be a function of the small lens used by the HD1. Most small lens camcorders that I own lose definition when filming distant landscapes. Admittedly, however, the HD1 distant-focus problem may be slightly worse than what I experience with small-lens SD camcorders.

I've pretty much resigned myself to use the HD1 for filming nearby objects/scenes (within 20-30 yards). The HD1 is great when used with a tripod/monopod --- minimal panning, ... for filming storefronts, antique cars, groups of people within conversation range, etc. I've also, found it to do a decent job in low-light, indoor (incandescent light) scenes. especially if objects, or faces of people are adequately illuminated.

In short, I've concluded that the HD1 is not a nature, landscape camcorder. Instead, it is a well-designed and decent, close-range high-definition hybrid camera/camcorder.

HDG
Hawood Giles is offline  
Old September 13th, 2006, 09:29 PM   #3
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I haven't tried mine extensively yet. I just got it today :).....But Carlos's footage 124 shots has some distant shots and they appear to be in perfect focus. I find that most cameras will appear clearer on close up objects than far objects. That is simly due to the detail you actually see when something is close as to when its far away. When far away a whole tree is a few pixels. When close you get to see each individual leaf in detail. Like I said I did not try mine out yet, but Carlos's footage seems to be fine in the far shots.
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Old September 13th, 2006, 10:24 PM   #4
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Intelligent scene selection

Paul,

I agree that the 124 clip material presented by Carlos is spectacular -- overall. But, 95% of his material is close-range. The 5% distant footage that he sampled is wisely chosen to include large interim structures; non-glare/haze distant skyline; and no distant leafy trees. Many of my own similar scenes come close to the quality of Carlos footage. However, I do experience focus problems when shooting across a vast grassland with trees in the distance and a bright (white/cloudy) skyline. Likewise, I've had difficulty filming across a large lake with bank of trees on the distant, brightly lit horizon.

I think that the HD1 is capable of consistently obtaining excellent results, as long as the operator is mindful of the camera's weaknesses in certain light situations --- and avoids shooting scenes which contain focus and blurring aberrations. If the soon-to-be-released HD1a improves upon, or eliminates the focus problems that I've experienced, I definitely intend to buy the new Sanyo HD1a.

HDG
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Old September 13th, 2006, 11:43 PM   #5
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Well, I must say that Carlos did have leafy trees in the distance in a few shots and they looked in focus, he also had mountains with trees on them past a lake and a good shot of boats far away on a lake that all appeared in focus. I'll have to try my HD1 and compare my results with some of Carlos's shots. I sure hope mine is as in focus as his on distant shots because I'll be using it for distant shots quite often. Carlos's footage is what pushed me over the edge to buy this camera, I hope I made the right decision. So far I had limited time to use it, I just received it today and basially just checked to make sure it works. Wish me luck.

Paul
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Old September 14th, 2006, 06:41 AM   #6
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It sounds like an issue of shooting scenes that require the apeture to stop down to its smallest opening. If you had access to a neutral density filter allowing you to choose more mid-range apetures, the diffraction problem should theoretically go away, no?
Lynne Whelden is offline  
Old September 14th, 2006, 09:30 AM   #7
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Limited aperture range

Lynne Whelden;

The aperture range of the HD1 when shooting video is rather meager: f3.5 to f8 . Not a whole lot of room to manually adjust the iris at the extremes.

I reviewed several of my HD1 clips with potentially challenging "focus" characteristics. Interestingly, some are superb, if not perfect; others are unintentionally "blurred" at extreme focal lengths, i.e. real close, or very far away. As for the ND filter, it tends to over-blacken the overall scene, close-up, or far away. Example: filming under a canopy of trees in an otherwise sunny and bright environment. Result: tree leaves are indistinct and too black; sunlit regions of the scene are a mix of acceptable color and blown-out, or "blurred" content.

Worth noting is that all of my HD1 footage looks better on the computer than it does, when the MP4 files are transcoded to mpeg2 DVD and played on a widescreen TV (SD mode). The same HD1 footage improves somewhat when those clips are played from my Toshiba HD-A1 (high definition) player; although the improvement is nowhere near as great as what occurs with standard definition video shot with my SD miniDV camcorders (upconverted to 480p or 1080i).

HDG
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Old September 14th, 2006, 10:11 AM   #8
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Well I also have a Sony HDR-FX1 3CCD HD Handycam at my disposal. I will do some testing and compare the quality betweein it and the HD1. I don't expect the HD1 to keep up to the Bigger 3CCD Sony but I must say that so far from what I've seen of the HD1 footage, there is no comparison to our previous Standard Definition 3CCD Sony Camera. Standard definition DV just has way less pixels and definition to keep up with the HD1 detail. I'm not sure why you are getting better video quality out of a regular DV camera than the HD1...

Perhaps I can see it on night footage or bad lighting situation where the Standard DV camera bigger lens just allows more light in and the HD1 is at the highwst ISO setting creating a lot of grain. But on a bright sunny day when you're recording on ISO50 or so, there HD1 should have way more detail than a 720 by 480 resolution camera.

Paul
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