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Old Apr 27, 2006, 7:57 AM   #31
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sue6389

I see your problem. That blurry image was taken at maximum optical zoom (equivalent to 432mm) + 4x Digital Zoom.

As I suspected, shutter speed was one contributing factor. In that lighting, the camera was using a 1/100 second shutter speed.

You effective focal length was approximately 1700mm after the Dgital Zoom (which is basically cropping an image, then enlarging it again).

The "rule of thumb" for hand holding a camera is 1/focal length. So, with that lighting and ISO speed, you'd have wanted shutter speeds of 1/1700 second (17 times as fast as the camera used) without IS. Even with IS, you'd be well outside of the design tolerances of the system.

For that matter, even without Digital Zoom, some users need to take extra care at focal lengths that long. Not everyone holds a camera as steady as others. You would have been right on the "edge" of the design tolerance for IS, even without using digital zoom.

Digital Zoom also degrades an image. Basically, when you use it, it's cropping a photo to make it look like more optical zoom is being used. Then, it enlarges it again to the image size you're shooting at. I keep it turned off on cameras I use with it, just to make sure I don't use it by accident.

If you use 2x Digital Zoom, you end up with only 1/4 the number of pixels captured by the camera's sensor (not 1/2 the number, since resolution is like area where you multiply width x height to compute it).

With 4x Digital Zoom, you end up with 1/16 the number of pixels captured by the camera before it enlarges again.

So, basically, the camera cropped the image to 648 x 486 (less than 1/2 megapixel) then enlarged it again back up 2592 x 1944.

2592 / 4 = 648
1944 / 4 = 486

That process degrades image quality. So, the use of digital zoom, combined with very slow shutter speeds for the effective focal length, resulted in a blurry image.

You would have experienced the same problems with another camera using the same settings.

My advise would be not to use Digital Zoom unless you really have to. Then, get out and take some photos so you're more accustomed to the camera.

Make sure you've got IS turned on (Shoot Only mode is probably your best bet), and if shooting into shadows, keep camera shake in mind (IS can help a LOT, but it's designed to work miracles at focal lengths that long. Technique still comes into the picture (smoothly squeeze the shutter button to help the camera out).

Camera shake is magnified as your focal lengths get longer (more zoom). You were not shooting at focal lengths anywhere near this long with your Maxxum. You were probably using film speed that was higher than the ISO speed these ultra zoom models use too (the higher the ISO speed, the faster the shutter speeds can be for the same lighting and aperture).

IOW, I would practice some with the camera so that you're more familiar with it's behavior. Your skill as a photographer, especially when trying to take shots at focal lengths that long, are going to be far more important than the differences between very similar camera models.

That's going to take practice.

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Old Apr 27, 2006, 8:21 AM   #32
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P.S.

If you leave digital zoom turned off, you can crop an image using software to accomplish the same effect.

But, you'd want to keep degradation in mind if you need to enlarge it again for printing. More often than not, if I need to use this technique, I'll use the Lanczos algorithm in the resize screens in Irfanview (you'll see it as one of the slow choices on the resize screen).

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Old Apr 27, 2006, 8:30 AM   #33
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Thanks Jim. So anything past the 12x is best to avoid (for now anyhow). I've printed out your advice/suggestions, and will go out tonight and do my homework.

And thank you for being so patient.
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Old Apr 27, 2006, 8:35 AM   #34
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Right. Short Answer:

Don't use the Digital Zoom.

It's going to degrade your image quality (for more than one reason) in many conditions. Digital Zoom is a marketing scam. It's only cropping an image then enlarging again.

Sony has a "smart digital zoom" feature which can crop only (cuts out the center portion to make it look like more optical zoom was used). But, you have to shoot in lower resolution modes to use it.

You can do the same thing using software with your Canon (crop an image).


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Old Apr 27, 2006, 9:34 AM   #35
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One more comment...

In addition to the samples we have showing photos of the same subjects from both cameras (Sony DSC-H1 and Canon S2 IS), you can sometimes find some other examples around the net.

Here is someone else that took photos of the same subjects in the same conditions with both models:

Canon S2 IS and Sony DSC-H1 Shootout

If you look for things like fringing, you'll see it in both cameras in some conditions. For example, this image from the Sony:

http://dwpeters.smugmug.com/gallery/1037479/1/48168834

Same subject with the Canon:

http://dwpeters.smugmug.com/gallery/1037480/1/48135118

In the end, this person chose the H1 (but found pros and cons to both). Each user is going to have their own preferences in a camera,.

There is very little difference in these two cameras from an image quality perspective, and an untrained eye probably wouldn't notice any at all at most viewing sizes.

I'd practice with it before going on your trip. No camera is going to give perfect results in all conditions.

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Old Apr 27, 2006, 11:42 AM   #36
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I think Jim covered it all, Sue. And yes, no digital zoom! Good luck with your S2 and happy shooting. I'm looking forward to see the photos from your trip.
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Old Apr 27, 2006, 2:40 PM   #37
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If you want a quality shot you can't use digital zoom and you must get close. Even then, taking photos of highly active small birds with the S2/H1/FZ7 in anything but good light at anything more than about 4m or 12 feet is really a hit and miss afair. Maybe 1 shot in 30 is worth keeping. The hit rate would be higher in open country - if you can get close enough. If a subject will keep still, the problems are greatly reduced. The same Stitchbird/Hihi image I posted was the result of several days attempts - on each trip I'd have to speed up to half and hour sitting at feeders and up to 3 hours walking between them - so this is what you're up for.

Don't use manual focus - use auto-focus, but pre-focus and focus-lock on the branch or feeder. If you do use manual focus, with the S2 you can use the manual focus to get in the ballpark, and then use the Set-button to let the auto-focus fine tune the focus point.

If you want to do better my guess would be that a DSLR with a 300-400mm lens might increase the chances. With the right lens you may be able to achieve much higher shutter speeds - and if you can keep the shutter speed up high, image stabilisation might not be necessary. I haven't tried a DSLR - so this is pure speculation. I'd expect the hit rate to improve some, but in my case it might only drop to 1 in 20. I think a professional bird photographer was quoted at 1 in 100 hit rate for a professional quality image.


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Old Apr 27, 2006, 5:28 PM   #38
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I thought I was done discussing the S2 (vs H1) but I guess not. I totally disagree with you, mchnz. I have two out of the three cameras you mentioned (the S2 and H1) and my experience has been such that I hardly ever miss a shot with the H1, despite the light conditionand/or the subject.Ithink that1 shot in 30 is about right with the S2 but not the H1.I'm pro quality, not pro brand.The S2 can and does take wonderful pictures (see Shaun's postings on various forums). If I did not think so, I would not have bought it in the first place. However, I must admit that its performanceleaves a lotto be desired (unfortunately) and that became very obvious to me after I got the H1. Following Jim's rational (to compare photos taken by two different cameras, the subject and conditions must be the same), I think you can onlymake statements abouttwo different cameras if you owe them and have personal experience taking photos with them, not by their specs or simplyby their reviews. None of the reviews out thereshows sample shots of live animals. They are all static shots of buildings and boats. How you canaccurately evaluate AF from building shots is beyond me. Let's put this way, any camera producing blurred pictures of a building being photographed in bright daylight,is garbage and I very much doubt people will buy them.
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Old Apr 27, 2006, 9:18 PM   #39
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I was specifically talking about

taking photos of highly active small birds .. in anything but good light at anything more than about 4m or 12 feet ..

without flash and with a desire for results similar to the image I posted. Which is to say the image must look good at around 1280x1024 resolution. I wasn't promoting any one camera over another - but there are obvious limitations to x12 point and shoot cameras.

The sensitivity of these cameras at ISO 100 is such that at x12 zoom, with the subject in the shade, the shutter speed will normally be well below 1/500 sec. Really active birds are difficult to photograph under these circumstances - all shots will contain some subject motion blur. Birds that have a less active habit are easier. If you hang around a feeder, birds will often pause on near by branches on entry or exit - this helps heaps.

ISO's above 100 have unacceptable noise - so that's not an option. Perhaps ISO 200 is OK as a last resort - better than no shot at all.

When using x12 zoom beyond 4m, a subject like a small bird becomes quite small. Cropping becomes difficult because any amount of noise, shake, or subject movement becomes very noticeable. For many small birds in bush/forrest, x12 zoom is probably not enough - how many birds allow you to get within 4m? Only a DSLR has the sensitivity to allow more than x12 in less than good light - plus with a DSLR's sensitity you can crop more. Note that with a DSLR, post-processing is said to be almost a necessity - so you have to be comfortable with that.

As for other larger subjects. I don't have much trouble with shooting any of the other subjects on my flickr pages ( http://www.flickr.com/photos/[email protected] ) - mainly noise in the shadows (which is par for the course on these small sensor, high mega-pixel cameras). I normally underexpose - I don't like overblown highlights - so I do expect to post-process images for contrast/brightness/gamma.

To sum up - get close, hope the bird holds still, and take your chances. Here is an example subject in total shade, x12 zoom, ISO 100, under exposed to keep the speed up, 1/30 sec, post processed to fix the under exposure):


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Old Apr 27, 2006, 11:18 PM   #40
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I hardly ever use flash, specially when I photograph wild life. I have the H1 ISO set at 64 most of the time and I also use the Sony DH1758 1.7x tele as well as the full 12x zoom when I take pictures of live animals. As long as it's not too dark, I can focus on just about anything at any distance pretty accurately (see example - the bird is at the top of an 80 foot tall willow tree between all sorts of branches and in the shade. Obviously I cropped a bit to showit a bit closer). All I have to do is set the AF to spot. It's dead on!
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