Photography

Canon Users Check Out CHDK

2008-05-16T03:54:00.000-07:00

CHDK is a software hack for Canon cameras that adds a great deal of functionality to low-end models. Because it is software that loads into memory and executes as opposed to a firmware modification, it does not pose any risk of bricking your camera. Simply restart your camera and functionality is restored to normal.

I have a Canon Powershot S2 IS, and there are a number of aspects of the camera that I have found very irritating. While this software can't fix the mediocre lens and sensor, it does allow you to get the absolute maximum performance they are capable of.

I enjoy night photography, but the combination of a maximum ISO rating of 400 and 15 second exposure maximum wasn't sufficient for many low light night situations. Also, the sensor is noisy and low contrast subjects show some noise even at ISO 50, and the camera firmware gives you no method of setting it lower.

While the software can't overcome physical limitations of the camera, it does overcome some nasty software limitations. I can now take exposures up to 64 seconds. During low light night photography the difference between 15 second and 64 second exposures is more dramatic than one might think. It really has made a difference in terms of the scope of things I can photograph at night.

Prior to this I recently discovered what I have come to learn is called "frame stacking", adding together the image data from multiple frames to simulate a longer exposure, there is nothing that prevents frame stacking from being applied to 64 second exposures further expanding the dark light capabilities of the camera.

When there is adequate light, I can now take advantage of lower ISO values to get less noisy images. Unfortunately, the image sensor in the S2 IS model does not seem to be capable of more than ISO 400, however, even ISO 400 is so noisy with this sensor that it's marginally usable.

CHDK also allows you to use the full mechanical range of the lenses F-stop settings. Unfortunately this only results in a very modest extension on the S2 IS because the lens is not capable of much more than F8.

CHDK adds the capability to capture raw images on Canon models. Older low-end Canon cameras and most newer Canon cameras do not have this capability built-in. This is useful if you are going to be doing post-processing since it preserves the full dynamic range of the captured image and there is no distortion or data loss resulting from jpeg encoding. You are then free to encode the image however you feel fit in external software.

The raw feature however does not give you the same quality as a good DSLR, the reason is that the sensors used on low end Canon cameras are only 10 bits/channel and tiny. 10 bits/channel limits dynamic range and the low size of the sensor limits light gathering capability and thus limits sensitivity and noise immunity. A DSLR will generally have a sensor that provides 12 bits/channel and generally has a larger sensor that can gather more light and provide a higher quality image with less lighting.

Another nice feature that is added is a realtime histogram. Before, I could only guess at night exposure, take the image, look at the image and the histogram, and then adjust and try again. Now, I can get the exposure close on the first exposure. This has resulted in a much larger percentage of my night shots being usable.

Another nice feature, CHKD offers the ability to monitor how much battery is left either in percentage or in terms of battery voltage. The existing battery monitor was almost useless when operating off of NiMH batteries as it gave only three values, full, half-full, and empty, and because NiMH is only 1.2 volts/cell the meter would only be "full" for the first few minutes of operation. It would then be half for the majority of operation and about three minutes before shutdown, it would be empty.

Now, I have a meter that reads 0-100%, and I can adjust the voltage thresholds for full and empty so I can have it reflect the NiMH batteries I use rather than Alkaline batteries. This gives me a much better idea of how much power I have left and helps avoid unexpected interruptions.

CHKD added some very nice video compression capability, the constant bit rate compression used by cannon was fixed at 1MB/S and video recorded at that compression ratio was good quality but with the 1GB limit it didn't even allow half-hours worth of video to be recorded in high quality. With the variable bit rate; I have found I can get reasonable quality and close to two hours of video on a 2GB card. The unit will still only allow one hour at a time to be recorded, even though it overcomes the 1GB file limit, an hour limit seems to be built into the units firmware. Fixed bit rate options ranging from .25MB/s to 3.0MB/s are available allowing even higher quality video than the original.

CHKD gives the user a great deal of control over what information is displayed, and there is a great deal of flexibility in how this information is displayed.

CHKD also has a built-in BASIC interpreter that allows users to write scripts to provide more complex functions and a multitude of such scripts exist, including motion detection. The motion detection is fast enough even for capturing lightning strikes. I have not had a chance to test scripts yet but will report back in the future when I do.

There is much more to CHDK, click on the title of this article to be taken to the CHDK Wiki which provides more information.

This photo is an example of one that would have been impossible without this software. It is taken only with moonlight and some light from a nearby homes porch light. Yes, there is some noise, but it would have been totally impossible without the additional two F-stops that the longer exposure time buys.

Overcoming Exposure Time Limitations - Night Photograph

2008-05-11T01:07:00.001-07:00

Tonight the sky looking towards Vashon and Bainbridge has some very interesting color and cloud patterns, but it is quite dark. A 15 second exposure at ASA 50 would barely produce a few lights in the sky and increasing to ASA 400 results in intolerable noise. The Canon S2 IS supports a maximum exposure of 15 seconds.

I took nine 15 second exposures without moving the camera or changing the settings and then added them together with PaintShop XI. I loaded each image into a separate layer and used the "screen" blend mode.

Here is my 2 minute 15 second exposure which captured the colorful sky very well. This was taken at 10:35 PM, about an hour and a half after sunset. The sky color is a mixture of moonlight, sodium vapor street light, mercury vapor street light, and other artificial lighting reflecting off of the clouds.

Experiments

2007-09-16T16:36:00.000-07:00

Corner

Empty

Recent Photos

2007-08-05T23:13:00.000-07:00

There are some random photos I've taken recently.

Kirkland Waterfront Park at Night

This is taken from a dock on Lake Washington at night. The lights in the park were sodium vapor. I used the custom white balance function on my camera to adjust to the color of the sodium vapor light.

The results are interesting in that neutral colors appear as if they were illuminated by white light but the colors appeared cold and washed out. Trees looked gray, the grass appeared green but a washed out green.

I used an effect in PaintShop Pro under film effects that is called "Warm Earth Tones". Doing so shifted the color of the sidewalk back to a slightly ruddy reddish color but not to the extreme of unadjusted sodium vapor lighting. Overall though the colors looked more natural than they did.

I have mixed feelings about outdoor lighting. Sometimes I think it would be nice if they switched to a good metal halide lamp for outdoor lighting, similar efficiency but much nicer color rendition, but then I remember I sold my telescope years ago when the light pollution became so bad that it was essentially rendered useless.

Big Bend Tree, River, Mountains

I took this photograph from behind a cabin on the Skykomish river in Big Bend. My oldest son is leasing the cabin from my mother in law and living there.

205th Eastward

I took this while stuck in traffic after leaving Aurora Village on 205th Street. I like the depth of the previous image and this one. Click on the image to see a big version which you really need to get the full effect.

Tripod Repair

2007-07-26T13:45:00.001-07:00

I went down to Kirkland last night and took a few pictures to test my tripod repair. I didn't get camera shake on any of them so it looks as if my repair was successful.

For those who haven't been following this blog, I have a tripod that has a removable piece that attaches to the camera for quick release. The shoe that it sits in had a rubber mat to provide tension so that it was a tight fit but that fell out at some point leaving the piece attached in the camera free to move around in the shoe causing camera shake.

I used some of the fabric portion of stick-on Velcro as a substitute for the rubber mat and it seems to provide a nice snug fit that completely solved this problem. The only shake I experienced last night is that I took some photos from a dock and occasionally waves from the lake would hit the underside of the dock hard enough to move it.

Seattle First Hill at Dusk photographed from Kirkland

Downtown Seattle at Night

Lake Washington Shoreline at Night

Click on any of these to see an enlarged version. The middle one especially but also the last benefit from this as there is a lot of detail not visible in the smaller image. The first image I think I did something accidentally bad like in Paintshop with the high pass filter and over emphasized the fine detail distorting the image.

When adjusting sharpness detail, if you have things not sharp enough, not enough high frequency content, a point will blur into a smudge. If conversely you have too much, then a bright point will get a dark ring around it. This can happen if you set the sharpness too high or if you accidentally run a high pass filter twice.

I've pretty much worked out a formula that compensates for this camera without overshoot which consists of running the high pass filter with a setting of two pixels and strength of 35, then a setting of one pixel with a strength of 70. This combination seems to compensate for the camera just about perfectly. I suspect I ran one an additional time on the first image.

Night Photography

2007-07-20T17:09:00.001-07:00

I went down to Alki recently, primarily with the intent of taking some pictures of KNND's setup for my radio blog but I also wanted to take some night shots.

Unfortunately, what I didn't realize was that my tripod had lost a piece. It's got a quick release mount for the camera and the piece that attaches to the camera sits in the head of the tripod originally on a kind of rubberized mat.

Well, that mat was glued in apparently not well and fell out and went unnoticed except that when I went to use the tripod the camera wouldn't stay still on the head. I have since repaired it by using a piece of the fabric portion of stick on Velcro which provides the necessary tension to hold the little camera mount plate stable.

But some of my pictures that day got some camera shake in them as a result because I hadn't figure out what was wrong with the tripod yet.

4th of July Fireworks

2007-07-05T23:55:00.000-07:00

This year I had a fair degree of success at photographing fireworks. The settings I used were approximately F3.5, 3.2 second exposure, and 400 ASA film speed.

I started with a 50 ASA setting but that proved inadequately sensitive. 400 ASA was good for most, might have been a little too sensitive for some resulting in color wash-out, but overall was probably a good compromise.

I took many more. You can see them on my July 4th gallery page.

Macro

2007-07-02T19:25:00.000-07:00

I've been playing with the macro capability on the Powershot S2 IS camera a bit lately. The following is a close-up photograph of a tiny flower being worked by a bee that, although I keep hearing has been dying off, seems to still be quite plentiful here in western Washington.

A limitation of the Powershot S2 IS shows up in this photograph. It is impossible to stop the lens down more than F8 and thus impossible to get a decent depth of field. A macro lens I have for my 35mm camera stops down to F22 which gives a depth of field just short of a pinhole camera.

Yes, I know I can't expect as much from a $300 digicam. Still I don't understand some of Canon's design decisions, particularly with respect to the lens on this camera.

Most Popular Image

2007-07-01T19:59:00.000-07:00

I've put over 700 images up on my gallery since I got the Cannon Powershot S2 IS. This one is one of the very first pictures I took, messing around at Golden Gardens just after I got the camera. It is also the most popular image on the gallery, viewed more than any other.

Girl In Water

Moire Pattern

2007-06-30T11:33:00.000-07:00

There is a type of color distortion present in digital cameras that can under certain circumstances be mistaken for chromatic aberration but it manifests itself differently. It is what is known as a Moire pattern.

Moire pattern first presented itself in color television as a result of overlap of sideband information in the NTSC color broadcasting system. In that system, color information overlaps high frequency (fine detail) video information and so fine repeating details, such as a plaid shirt or pen striped suit, would result in a rainbow effect.

Digital cameras also are subject to Moire pattern but for a different reason. In digital cameras, the pixels each respond to a specific color, red, green, or blue. The geometric pattern that they are laid out in can result in banding when a high contrast line cuts the pattern.

In the following example, the fence top rail wasn't quite horizontal in the original photo and was made horizontal with the straighten tool. Because it was originally at an angle, it cut the pattern of pixels at a slight angle and acquired this rainbow banding as a result.

It should be noted that this is a small portion of a much larger picture and without being blown up and having the color exaggerated it probably would have gone unnoticed.

The strongly predictable nature of the Moire pattern from a digital camera makes it very amiable to software removal. The internal firmware of many cameras do this well enough that you may never notice this, but if you do, know that you can fix it using external software.

In this case, I used Paintshop Pro X's Adjustments->Add/Remove Noise->Moire Pattern removal. While I was at it, I also adjusted the brightness curve because the original looked kind of dark and dreary to me, that's a matter of personal taste or in my case, lack thereof. The important thing to notice is the banding is gone.

Chromatic Aberration

2007-06-27T14:21:00.000-07:00

Chromatic aberration is an ugly effect that manifests as colored fringes around high contrast areas of photographs.

Here is an example of chromatic aberration. This shot was taken with a Canon Powershot S2 IS at maximum zoom on a day with direct sunlight.

Normally, chromatic aberration is non-existent in the very center of an image and gets worse as you move towards the edges. This is not the case in this example only because it was cropped from a larger picture.

Lenses work by refracting light. Shorter wavelengths are refracted to a less degree than longer wavelengths. This causes light at the red end of the spectrum to not focus in the same place as light at the blue end of the spectrum. This manifests itself as a red fringe on one side of a high contrast line and a blue or blue-green fringe around the other. The blue-green fringes are often less noticeable.

Various techniques are used in modern lenses to reduce this effect. Special "achromatic" glasses which have refractive indexes that vary with wavelength reduce this effect. Also, lens elements can be arranged such that one element cancels chromatic aberration induced in another.

There is a broad range of lens qualities, the old adage that you get what you pay for applies. Generally speaking, chromatic aberration gets worse with focal length because there is more magnification to magnify any aberration in the first elements. With telephoto lenses, reflector lenses (mirrors) don't have chromatic aberration, refractive (glass) lenses do. Glass lenses have higher contrast than reflector lenses.

Zoom lenses are more problematic than fixed lenses because of the changing relationship of the elements which makes it difficult to use the aberration in one element to cancel that of another. The Canon S2 IS is particularly bad in this regard because it has a 12x optical zoom with a max focal length of 432 mm.

That said; I really wish I had a decent SLR with a set of decent fixed focal length lenses because on the Canon Powershot S2 IS this problem is substantial and ruins a lot of what could have been good photos.

Here is another example of chromatic aberration followed by attempted software fixes.

Paintshop Pro X has a feature called chromatic aberration removal (I'm sure Photoshop and other similar programs also have this but I'm too poor for Photoshop, Paintshop is inexpensive). To use it, you invoke it then select the fringe area. It removes and tries to extrapolate the correct color where the fringe was.

Two bad things often happen. One, the color of the fringe includes colors close to colors in the photo and they get removed as well. Here is an example.

The other thing that can happen is that the software can substitute the wrong color when it replaces the fringe.

I took another shot at it and was able to remove most of the fringes and only do minor damage to the skin.

I was able to do less damage by selecting different points in the fringe which had a slightly different color and the overall results were better. Some images just plain are not repairable and I wouldn't consider this one repaired sufficiently for anything but the most casual purposes.

Bikinis

2007-06-27T01:44:00.000-07:00

I'm pretty sure the entire female population of Kirkland was in bikini's on waterfront today.

Reorganized Gallery

2007-06-24T18:06:00.000-07:00

I've totally reorganized my photo gallery again. I need to be able to find photos for web work and what not and it was just totally too jumbled. I know this photograph totally ignores the thirds rule but I really don't like formula art, music or photos or anything else.

Eagle In Flight

2007-06-13T23:13:00.000-07:00

I had taken my wife down to a class in Sandpoint just off of Lake Washington in Seattle to get her food handlers card, and while waiting I went to Matthews Beach just north. I was sitting at the edge of the lake following swallows with my camera just to practice keeping a moving object in sight when all the sudden I had an Eagle in the view finder and took this photograph.

At the Beach

2007-06-01T22:57:00.000-07:00

Pro Beach Volleyball?

You mean people actually get paid for that? Tough life.

Slack-Line

This is cool. Something I've never heard of before called a Slackline. Basically, it attaches between two trees and then you walk it. Like a tight rope except it's a flat band.

Digital Camera Batteries

2007-05-29T19:21:00.001-07:00

There is a lot of talk on the net about digital camera batteries. If you've got a digital camera that uses AA batteries and you prefer to use nickel metal hydride rechargeable batteries, then I would strongly recommend PoweriZer brand "Professional for Digital Camera" batteries.

The performance of these batteries is nothing less than incredible. I've used these batteries in two different cameras for almost four years and their performance has remained phenomenal.

I bought a Minolta DiMage Z1 in the late summer of 2003, with an extended warranty. It came with a set of Alkaline batteries which it completely sucked dead in fifteen minutes. I quickly realized that feeding it Alkaline batteries was going to be an extraordinarily expensive proposition so I went and bought a set of Radio Shack NiMH rechargeable batteries. They only gave me 15-20 minutes per charge which was quite frustrating.

It became clear that I was going to have to buy multiple sets, but Radio Shacks were pricey so I went looking on the web for something more reasonable. I found a 24-pack of PoweriZer "Professional for Digital Camera" batteries, rated at 2250 MaH for $24 (with free shipping), so basically $1/battery which was about 1/5th Rat Shack's price.

These batteries provided about four hours of service in the Minolta DiMage Z1, or about 300 photos depending on how much active shooting / idle time. After about two years of usage, the Minolta broke and so I sent it in for warranty repair. Good Guys managed to lose the camera, or accidentally sell it, and after a year finally admitted to it and it was replaced with the Cannon PowerShot S2 IS, which overall is a superior camera except I think the Minolta lens was better (the Cannon PowerShot S2 IS tens to be subject to chromatic aberration and vignetting under certain circumstances).

With the Cannon, I get at least eight hours of camera time with these batteries. I can fill up a 1GB memory card, with 500 or 600 (sometimes more depending upon resolution) shots, download to the computer on battery power, clear the card, and still have battery power left over.

These batteries are four years old and still going strong. While I bought enough to have multiple sets in practice I never use them. One set stays in the camera because I can shoot all day on one set.

I have no affiliation with the companies that manufacture or distribute these batteries. I have just been very happy with the performance of these cells and they're inexpensive. They are made in China but they way outperform the Radio Shack cells and from what I've read most of what else is out there.

I've read many instance of people using 2600 MaH batteries and only getting 100-300 shots with the PowerShot S2 IS, while I'm getting 500-600 plus (and probably more if I had more than a 1GB memory card) with these batteries rated at 2250 MaH. I've read of people having to replace batteries only 2-3 years old, I use these heavily and they're still going strong towards the end of a fourth year. Absolutely no hint of decreasing capacity.

New Panasonic CMOS Image Sensor

2007-05-19T20:04:00.000-07:00

A May 15th press release article, on Panasonic's website, describes a new image sensor technology that looks pretty promising.

Most of the time when I read a press release on a companies website, I take it with a bag of rock salt because a grain just won't do it. However, I believe this technology offers some genuine benefits.

Existing sensors use dyed polymer (plastic) filters to filter red, green, or blue light onto appropriate sensors and polymer (plastic) micro-lenses to focus light onto the photosensitive portion of the pixel. Such a thin layer of dye is readily bleached by UV light. Even with UV filters enough UV gets through to damage the dye filters over time causing digital cameras color rendition to degrade with time.

With existing CMOS sensors, the actual light sensitive region only occupies about 30% of the chip surface so to improve sensitivity they use micro lenses over the individual pixels to gather light from a larger area and focus it on the pixel. This is not without it's own problems because the micro lenses are less effective for light coming at them from an angle rather than straight on and thus pixels away fro the center of the image receive less light assuming the micro lenses are identical.

In addition to the limitations of this technology in terms of durability and image quality, the use of polymer on silicon is expensive. Everything has to be just so in order for the micro lenses to properly overlay the individual pixel sensors uniformly.

Panasonic has eliminated the need for polymer on silicon by incorporating sub-wavelength features on the chip die allowing for the construction of Fresnel like micro lenses and light filters directly out of silicon. Since the filters rely on physical structures, they are not susceptible to UV induced fading. Since the lenses are made using standard photo lithography techniques, they can be can be customized for their position on the sensor surface and compensate for the angle of incident light.

Since the new CMOS sensor should be cheaper to manufacturer it might just find it's way into some of the lower end cameras presently utilizing CCD image devices.

Everything I've read says that CCD's have higher sensitivity and lower noise than CMOS devices, but my own experience has been exactly the opposite. This might have to do with the fact that I like to do a lot of night photography and utilize long exposures so much of my utilization is atypical.

Happy Mother's Day

2007-05-12T20:05:00.000-07:00

I made this for my mother from a photo I took yesterday.

Robin

2007-05-11T23:33:00.000-07:00

Not An Eagle
Perched On The Neighbors Carport Roof

Eagle

2007-05-07T11:16:00.000-07:00

I took this picture at Juanita Beach in Kirkland Washington. I've never seen an Eagle not in captivity before. They are a very majestic and impressive bird.

Celine

2007-04-25T17:13:00.000-07:00

Digital Manipulation of a Photograph of Celine

Mostly Unhappy

2007-04-23T19:26:00.000-07:00

I am mostly unhappy with my photos. I'm not happy with them frequently on technical grounds and frequently on composure grounds.

Technically, part of the issue is equipment and part of it is operator malfunction. On the equipment side of things, the camera that I use, a Canon Powershot S2 IS, suffers from two major problems. The sensor is noisy. Even on the lowest ISO setting (50 ASA) it can not produce a completely noise free image. Second, the lens has serious flaws. At the widest angle it has obnoxious vignetting. At the longest setting it has obnoxious chromatic aberration. I can remove much of the chromatic aberration using Paintshop Pro, but it's tedious to do a good job without hurting the image.

The lens extended out is 430mm 35mm equivalent. With my 35mm cameras, I've got a 500mm glass telephoto lens (not mirror type), and on it chromatic aberration is only noticeable if I stack a couple of 2:1 teleconverters in front of it making it 2000mm. And this was an off-brand not that expensive lens. I am disappointed that Canon feels that people who can't afford a DSLR should be consigned to bad optics.

So that's the technical issue on the camera side. Then there is the operator side. Usually I get the image focused, usually I get the exposure pretty good. Sometimes with night photography I have problems because the 15 second shutter speed limitation prevents me from getting an adequate exposure and also it can be difficult to focus at night because sometimes there just isn't enough light to see to focus manually and auto focus goes south if there isn't enough detail or contrast. In those cases I end up guessing the distances involved and manually focusing accordingly, and if time permits I'll bracket the focus. So while I usually get those things right, sometimes I don't.

Camera shake, I am always trying to push hand-held past half a dozen stops past the point where I should have used a tripod. The image stabilization helps a lot, it's probably good for a solid three stops. I find myself taking pictures that looked good in the tiny LCD monitor but when I load them into the computer there is motion blur.

Depth of field, not always conscious of this as I should be. The camera is also way too limiting in this regard. The iris only stops down to F8, you can't get a deep depth of field no matter what you do with this camera. So sometimes even when I am conscious of it I can't get the deep field I would like or if I'm photographing a person I can't blur the background as much as I would like. I can fake it in Paintshop but there again it's tedious.

What I am most unhappy about though is composition. I lose sight of context. I take a photo of something I think looks really cool, but I back and look at it and it is dull. I neglect sometimes to include things to provide context. I'm not aware of them when I'm present taking the pictures.

I know about the thirds rule but I hate formula photos so I often intentionally don't follow. Sometimes my deviation from formulas works out alright other times it sucks. More often than not the later.

I hope these things will come automatically with enough practice.

Broken Sky

2007-04-23T19:20:00.000-07:00

Strange Sky

Wave

2007-04-19T17:10:00.000-07:00

Wave at Richmond Beach

Canon Powershot S2 IS

2007-04-17T21:56:00.000-07:00

The Canon Powershot S2 IS is an older model. It has been superseded by the Powershot S3 IS.

CompUSA provided this camera as a replacement for a camera that they lost (or sold at a clearance sale accidentally) during a warranty repair. The camera it replaced was a Minolta dImage Z1.

The only real downside to the Canon verses the Minolta is that the optical quality of the lens on the Minolta was superior. The Minolta had a 6:1 optical zoom, the Canon has a 12:1 optical zoom. The Minolta produced high quality images, within the limitations of it's 3.2 megapixel sensor and inferior software, across the full range. The Canon suffers from chromatic aberration at long lens settings and vignetting at short lens settings which together limit the usefulness of all that zoom range.

Now that I've had the camera long enough to really become familiar with it I thought I'd write a little review for those of you contemplating a used S2 and in all probability it shares a lot of traits with the S3 since the design appears almost identical and the specifications are only slightly different.

There are three major things I dislike about the camera. The problems with the optics that I mentioned above, chromatic aberration and vignetting, a shutter speed limit of 15 seconds, an F-stop limit of F8 max, a six-leaf iris, and a noisy sensor.

The chromatic aberration I can mostly fix in software. PaintShop Pro has a chromatic aberration removal tool that works quite well but is time consuming to use effectively. The vignetting is another matter. If the subject contrast is high then it's not too noticeable, but for low contrast subjects like clear skies it is very noticeable. The lens is a bit longer than I would like at the widest angle setting so I find myself often using the very widest angle where vignetting is the worst. Given the predictable nature of vignetting I'm surprised PaintShop doesn't have a tool for this and that the camera firmware doesn't compensate.

At night sometimes 15 seconds is not enough exposure even at 400 ASA, and because of noise I prefer to not use anything above 50 ASA. Even 50 ASA isn't completely clean. Some longer shutter speed options out to several minutes would really be a large bonus. A higher ASA film setting would not be useful without a higher quality lower noise sensor.

The lens can't be stopped down below F8. This makes it impossible to get a large depth of field. I used to have a Mamiya 35 mm camera, and some of the lenses I could stop down to F22 if I wanted to and have virtually everything in focus.

The six leaf shutter of the Canon Powershot S2 IS also causes six pointed star artifacts on city lights at night. I really think they cheesed out on the lens of this camera, that's really it's biggest weakness, but sensor noise is also a significant problem. In addition to the usual "noise" (fine grained snow), the sensor also seems to be prone to "stuck pixels", red or blue almost always, that stick "on" in low light. At first I thought these were just defective pixels but they change from time to time. If they were fixed it would be easier to deal with in software.

There are things I really like about the camera. The software that derives an image from the sensor is vastly superior to that which was in the Minolta. It squeezes a lot more resolution out of those 5.3 megapixels than the Minolta managed out of 3.2 megapixels given the simple ratio. That to say the image is much sharper than the upgrade from 3.2 to 5.2 megapixels would indicate. Canon seems to do a much better job of extracting chroma and luminance information from the pixel array cleanly.

It may be this in part that reveals the flaws in the topics. The resolution on the Minolta may not have been good enough for the chromatic aberration to be noticeable.

Image stabilization is an incredibly useful feature. It substantially improves what you can get away with and makes hand held photography possible sometimes with exposures as much as second long. That depends of coarse upon conditions, but it's easily two or three stops more than what I could get away with without it. Image stabilization works particularly well for video giving video shoots a much more professional appearance. The zoom is also operational when shooting video and it is quiet enough that it doesn't noticeably affect the sound.

The audio in the Canon is actually very good quality, not what I'd expect for in body microphones. The Minolta had only 8 KHz sampling (telephone company quality), the Canon will sample up to 44 KHz 16-bit stereo (CD quality). The microphones manage to produce reasonably good base and uncolored crisp highs.

The Canon has buttons for most things important so that it is possible to make adjustments rapidly. It also responds to the shutter very quickly if focused in advance. This means a lot more photo opportunities that would have been lost with the Minolta due to having to do everything with one set of buttons through menus.

Another strong feature of the Canon is that it is a real power miser. The only times I've had batteries go dead on me is when I first used a set of nickel metal hydrides that had been sitting a year without use and another time when I had the automatic shut-off disabled and it accidentally got turned on and left on until they were drained.

I've taken more than 300 images on one battery charge and until recently that was all I could fit on the SD memory card. Recently a friend gifted me a 1GB card that I've yet to fill up so I don't know if the card or batteries will exhaust first now.

Neither the Canon Powershot S2 IS nor the Minolta dImage Z1 had a hot shoe or an external jack for a remote flash. Neither had a provision for a remote shutter release that didn't require a computer. These seem like fairly simple things that a good design would incorporate. Both had a video output jack. If I had a choice between video and a remote shutter release and flash control, I'd take the latter.

The Cannon Powershot IS autofocus sometimes functions erratically. I can take a number of pictures of the same subject using autofocus and most will be in focus but some will not. This can occasionally lead to a lost good photograph. It also doesn't seem to focus entirely accurately. I can sometimes obtain better results if I am not in a hurry by focusing manually.

The operational temperature is listed as 32-104F. I have operated the camera at temperatures below freezing and it showed no ill effects.

All in all, this camera is a mixed bag. Battery life is excellent. The image stabilization really is a major plus. The firmware is good. The controls are good. The flexibility is good but not quite as good as I'd like. The lens quality and sensor quality leave something to be desired. I like the overall aesthetics of the camera. If I had the same amount of money to spend again I don't know if I'd go this route or not.