Tuesday, November 30, 2010

G6 and G12: RAW Noise and Reduction


Based on the in-camera JPEGs, it seems to me that the G12 is about two stops better than the G6 with respect to noise. But then I began to wonder if this apparent difference was actually due to noise reduction software in the G12. To test this hypothesis, I took another look at those images but this time from the RAW image files.

The above 100% crops (click to see full size) were processed from the RAW files using Adobe Camera Raw. The G12 profile for ACR is still a “beta” but is probably representative. Processing for both the G6 and G12 was as follows:

... as shot auto white balance
... auto toning
... medium contrast curve
... ACR sharpening at 80%, 1 radius, 30 detail, 60 mask
... 0 noise reduction in ACR
... default noise processing in Noiseware Pro.

This time I skipped the G12 ISO 800 and used ISO 1600 and 3200. The G6 ISO 400 image cleaned up nicely but the G12 still has less noise – I think about two stops improvement but perhaps only 1-1/2 stops.

Sunday, November 28, 2010

G6 vs G12: Noise


As noted previously, there seems to be little difference between the in-camera JPEGs produced by the G6 and G12 when the images are seen on screen (without pixel peeking) or viewed as an 8x10 print.  But those images were made at the lowest ISO settings.  What about comparing higher ISO results?

Fortunately, my low light test scene had remained relatively untouched since the comparisons between the G9 and G12 at high ISO settings.  The above shot was taken with the G6 at ISO 400, f4 and 0.6 seconds.  (Apparently about 2 stops less available light from the previous tests -- don't know why.)  Not too bad at first glance (click for enlarged view). I also re-tested the G12 under the same lighting conditions.

Next, we yield again to temptation and take a peek at the pixels.  The assembled comparison below shows various 100% crops from both the G6 and G12 (click for enlarged view).

Based on pixel peeping, one might say that the G6 is not usable at ISO 400 but as seen in the opening image, small image sizes could still be OK.  It appears to me that the G12 is about 2 stops better than the G6 with respect to noise.  That is, I'd prefer to use the G12 at ISO 1600 than to use the G6 at ISO 400.

Of course, the G6 has a one stop aperture advantage over the G12 but then the G12 has image stabilization for which is claimed a two stop improvement in shutter speed.

My conclusion is that, in spite of having fewer pixels, the G6 is "noisier" than the G12.  Whether the G12 noise reduction is due to improvements in sensor technology or noise reduction processing in-camera, I couldn't say (probably both).  Obviously, there is more to noise than pixel count or pixel density.

Friday, November 26, 2010

G6 vs G12 JPEGs

Although not exactly a shoot out, here are a couple of similar shots taken with the G6 and the G12. All shots are uncropped in-camera JPEGs but reduced in size for blog use. All shots were taken handheld in Av mode at the lowest ISO setting and without any exposure compensation. In other words, a "trust the camera" mode.

First, the G6:

Then the G12 (slightly zoomed in to produce roughly the same scene);

Next the G6 at full telephoto:

Then the G12 at full telephoto:

You might well wonder "What's the point?" and that is the point:  At these reduced image sizes from automatically processed files and translated by the Internet, there is little difference between these -- and many other -- cameras.  Perhaps, better said, somewhat similar cameras, especially from the same manufacturer, produce similarly good results for general use on the Internet.

More generally, how should images be compared?  In my mind, the comparison should be made with respect to how the images will be used.  I have no problem with limiting some cameras to small displays onscreen and reaching for a larger format when the objective is a large print.  In the case of this G6 and G12 comparison, my next step was to make 8x10 inch prints from the in-camera JPEGs.  Both the G6 and G12 prints looked fine; in fact, almost indistinguishable.  Whereas an 8x10 from my 4MP G3 was sometimes a bit of a push, I conclude that 7MP is "enough" for an 8x10 (provided, of course, that those seven million pixels are "good" pixels").

(I've taken pictures of this same scene and made comparisons between other cameras as well.)

Wednesday, November 24, 2010

G6: Pictures


Here are some pictures of my "new" G6.  As could be better seen in the comparison to the G3, G9 and G12, the G6 is relatively large.

Although some must like it, I don't care for the mode dial being on the back of the G6.  I very much prefer that it be on top as it is in the G3, G9 and G12.

The articulated display screen was not included in the G9 and I missed it very much.  The articulated display on the G12 is significantly larger, brighter and higher resolution.

The hand grip on the G6 was larger than the one on the G3.  The G9 had no grip at all which led to Richard Franiec creating and marketing an add-on grip.  Canon must have been listening because the grip returned -- albeit in a much smaller size.

The G3 and G6 have informational displays on top whereas the G9 and G12 do not; however, I have to admit that I quickly became accustomed to the control dials on top and informational display on the back LCD of the G9 and G12

Monday, November 22, 2010

G: 3, 6, 9, 12


Canon introduced the PowerShot G series with the G1 in September 2000. Since then, there have been ten G series cameras; the current version is the G12. For various reasons, usually said to be “bad luck”, there was no G4 or G8. This means that the G12 could have been marketed as the “Tenth Anniversary Edition”; however, it was not. Strange.

I began my G experience with the G3, still have it and use it on occasion. I learned a lot about photography in general and digital photography in particular by using the G3. This blog was begun a few years after getting the G3 but does include posts about the G3.

Although greatly tempted by the G6, my next G was the G9 and I've written about it extensively. In fact, counting the labels, there are 132 posts in this blog that are labeled G9. I still have my G9 (as you might guess, I tend to keep cameras!). It is a fun camera and my goal – nearly achieved – was to squeeze every bit of performance from it that I possibly could. I've now transferred that goal to the G12.

I've not regretted skipping the G5 and, without RAW, did not consider the G7. But that skipped G6 remained a missing link until last week when I was able to find a good one. Now that I have a working G6, I'll play with it alongside the G12 for a few weeks. Meanwhile, here's a summary comparison of the main features of the G3, G6, G9, G12.


Saturday, November 20, 2010

G12: Name your camera

My G12 is rarely connected to my computer. I normally use BreezeBrowser Downloader Pro when downloading images to my computer directly from the memory card.  But the G12 must be directly connected to your computer in order to “name” it.

I remembered that entering my name into the G9 was awkward but did not remember the procedure. I did not have my name in the G12 until a few days ago. When I connected the G12 to my computer, nothing popped up. I then opened and ran "Camera Window" and fumbled around a while. Finally, I clicked on the "Preferences" icon (upper right of window, next to the ? icon). Then clicked on "Connected Camera" to add my name. Even though the text box was empty, I couldn't type in it until I clicked on "Edit". Finally, clicked on "Set" and exited the procedure.

This reminds me of a forum message from a few years ago. A guy discovered that he was considered to be the photographer for some porn photos but he had not taken those pictures. In fact, he had sold the camera. However, he had entered his name into the camera as the owner and did not remove his name when he sold the camera.  Be warned!

G12: Complete review at Imaging Resource

Don't know how I missed it, but Imaging Resource has published their review and tests for the Canon G12.  This is a complete review including tests and hands on experiences.  Well worth reading.

Wednesday, November 17, 2010

G12: Gordy Strap


According to me, a wrist strap is just right for the G series cameras. In fact, I don’t understand why Canon doesn’t include a wrist strap in the box. I almost never use the included neck strap. For my G3 and G9, I used Canon camcorder wrist straps. There are also many variations of third party wrist straps. After browsing around, I finally decided on the Gordy strap from Gordon Coale.

The Gordy strap is stout, easily installed, looks good and feels good. I also like the idea of supporting an individual’s creative efforts and, besides, everyone should support “Gordon”.

The Gordy strap is available in standard or longer lengths. The standard is about right for me but someone with larger wrists or hands will want the long version.

On the other hand, I also ordered and paid for a wrist strap from “Cool Lanyards”. Sadly, that merchandise has not been delivered and I’m not the only one complaining. I’ve contacted their customer support and received a reply via email but still no wrist strap. Apparently Cool Lanyards was once a legitimate business but I suspect is now a scam – best stay away.

Sunday, November 14, 2010

G12: Going Wide


Whereas my G9 was obviously designed for both wide angle and telephoto add-on converter lenses, the G12 apparently is not designed for wide angle converter lenses.  I say this simply because the G9 menu included a setting for wide angle converter but the G12 menu does not.  In addition, the G12 instruction manual includes the Canon TC-DC58D telephoto converter but not the wide angle converter and Canon does not list wide angle converters as accessories for the G12.

On the other hand, Canon does not say "Don't never, ever use a wide angle converter lens with the G12!" and I happen to already have the Canon wide angle converter lens WC-DC58B which is a 0.75x converter.  When used with my G9, the WC-DC58B produced a focal length of 26mm (in comparison to full frame 35mm film cameras).  With the G12, the same converter lens would produce a focal length of 21mm -- if it worked.

Of course, the WC-DC58B does work with the G12.  As shown in the above photo, the 21mme view is quite wider than the natural 28mme of the G12.   The inside view is from previous photos of the ski lake and the wider view is with the 21mme attached.  (Photo made by superimposing pictures and drawing an outline around the 28mme picture.)  The trick to getting the wide angle converter to work is proper mounting on the camera.

Vignetting can be a problem in mounting wide angle converters to the G12.  To mount auxiliary lenses and filters to my G12, I use the Lensmate adapter system.  In the Lensmate system, the "A" adapter is shorter than simple one piece adapters but is long enough to mount the WC-DC58B wide angle converter lens and also has the proper 58mm threads.  To get the above photo, I carefully screwed the converter lens into the adapter while continuously chanting "DO NOT ZOOM!  DO NOT ZOOM!".  It seems to me that this combination works.

To test the reports of vignetting, I next tried the WC-DC58B on the full Lensmate adapter (A+B components).  Yes, vignetting is a problem because the converter lens is not close to the camera lens.  With a little zooming, the vignetting disappears but so does the advantage of the wide angle. 

Although I've read reports of difficulty in focusing the G12 when the wide angle lens is attached, I've not found focusing to be a problem -- perhaps because I use the small Flexizone frame with my G12 just as I used it with the G9.  Of course, depth of field is really deep at 21mme!

On the other hand, reports of focus problems might actually be a result of reduced image quality.   The convenience and price is great but, just as in the days of film, these simple screw-on converters have adverse effects on image quality.

My conclusion is that I'll occasionally use the WC-DC58B with the Lensmate "A" adapter on my G12  (DO NOT ZOOM!) for convenience but my preference is to stitch multiple images when the goal is an enlarged print. 

Saturday, November 6, 2010

G12: Back to the Lake

With the Lensmate adapters, a polarizing filter and a graduated neutral density filter, I returned to the ski lake scene to make comparative pictures.  The G12 was mounted on a tripod and set for ISO 80, Av mode, f4 and the widest angle (28mme) focal length.  The actual exposure varied with the filters.  I tried to work quickly but still took several minutes.

The photo below is the base case without any filters.  Shutter speed was 1/125 second.  Notice the nice reflection in the lake; however some of the dark areas lack detail.

The photo below was made by adding the graduated neutral density filter.  Notice that some of the reflection has disappeared.  I think that the lighting changed slightly but I didn't notice it at the time.    Shutter speed was 1/160 second.

The next picture is with the polarizing filter.  The effect of polarization can be seen in the LCD display screen.  I rotated the filter to darken the sky and bring out the clouds.  Exposure was 1/40 second.  Nice, but notice that the reflection is significantly reduced.

Finally, without using filters, I made nine images for constructing an HDR picture.  I set auto exposure bracketing at -2, 0, +2 to get three shots; then changed to -1 exposure compensation and repeated; then changed to +1 exposure compensation and repeated.  This procedure gives exposures at -3, -2, -1, 0, +1, +2, +3 and two duplicates.  I used the seven shots to make an HDR 32 bit image using Photomatix and, with a bit of trial and error, selected the tone mapped version called "Compressor".  A little more post processing in Photoshop produced the version below.

For the HDR image, I did pump up the color saturation a bit but was attempting to tone down the sky and bring out the shadows without creating the overdone appearance that gives HDR a bad name.

The HDR part of the project was a last minute decision (I was in a hurry to set up for Halloween) and I completely forgot about using the G12 "HDR" function so that comparison will have to wait a while.

Thursday, November 4, 2010

G12: Lens Adapters


The flexibility of the G12 is greatly enhanced by using a lens adapter. With the right lens adapter, the G12 can be fitted with filters, close-up lenses, wide angle converter lenses and telephoto converter lenses. Although Canon makes its own adapter, the LA-DC58K, I decided to use the Lensmate adapter, Canon G12/G11/G10 Adapter, which comes in three sections: A, B, C (see above photo, left-to-right). Lensmate developed their system in response to vignetting complaints about the Canon system and answers some questions in a FAQ page. I decided on the Lensmate system based on my favorable experience with Lensmate adapters on my G9.

In the Lensmate system, Part A is the base and is always used as the connection to the camera body. Part B terminates in a 58mm filter thread and is the same outside diameter as Part A. Part C flares to a diameter larger than Part A and terminates in a 72mm filter thread adapter. The basic idea is that Part B is used to mount telephoto adapters and close-up or macro lenses whereas Part C is used to avoid vignetting at wide angle focal lengths. Part A can actually be used alone to mount filters or wide angle converters; however, care must be taken to avoid zooming the lens into the filter or conversion lens. I bought the full set of A, B, C adapters.

With the A and B parts, filter size is the same as for the other G series cameras so I already have the polarizing and graduated neutral density filters. The 72mm filter for part C is quite large but I have 77mm filters used with DSLR lenses. I could get adapter rings but am considering a Cokin system with adjustable graduated neutral density filters. It seems to me that polarizing filters do not create even effects for wide angle lenses.

The above photo is the G12 as fitted with A and C adapters.  There are handling, protection and perception advantages when the adapter is mounted on the G series and some users prefer to use an adapter all the time. I normally use the adapter only when necessary.

Monday, November 1, 2010

G12: Halloween


I couldn’t resist rigging up the G12 to grab a few Halloween shots. Because of low light (wouldn’t be Halloween otherwise, right?) the pictures would probably show a lot of noise and motion blur but that would be OK. Besides, these were just for fun.

Custom modes are great for saving the setup. I placed the G12 about 10 feet away from the candy hand-off spot, set the widest angle focal length and focused manually. The power saving function was turned off and the display was turned off. The camera was in Av mode at f5.6, ISO 800 and shooting RAW + JPEG. These settings were saved as custom mode C1.

The shot above is seriously cropped (using about 1/4 the full size) from the RAW image and then downrezzed to 800x600.  It was taken at ISO 800, f5.6 and 1 second exposure.  Noise reduction was applied in Adobe Camera Raw (ACR).

Actually, I messed up – or, better said – can make improvements next time with the experience gained. For starters, I should have used Auto ISO and set the maximum ISO at 3200. Sure, the images might be noisy but so what? By using f5.6, the depth of field is from 2.5 feet to infinity when the focus is set for 10 feet. But even at f2.8 the depth of field is from 4.1 feet to infinity! I should have set f2.8 for the low light and set focus at the hyperfocal distance of 7 feet to achieve focus from 3.5 feet to infinity.

Finally, I forgot that the slowest shutter speed for the G series in Av mode is 1 second. This has been a frequent complaint about G series cameras. Of course, no little goblin is going to remain in one place for more than a second anyway so the 1 second limit did not really cost me any pictures.

The G12 was triggered by the Yongnuo RF-602 wireless trigger. Normally used with flash, the RF-602 can also trigger the G12. When fitted to the G12 with the Yongnuo shutter connecting cord LS-02/C1, the RF-602 acts much the same as the Canon wired remote RS60-E3. In addition to its hotshoe connections, the RF-602 transmitter has a button that can be pressed to activate the receiver. It even has the “half pressed” shutter button function!

The G12 battery, an NB-7L clone, easily lasted the setup time plus roughly 75 minutes of being ON without the G12 power saving feature. Of course, the display was OFF. In fact, I’d used the G12 earlier that day for about 15 minutes and then viewed the results of the Halloween shoot for another 15 minutes later that night. I don’t remember how much battery power was left but nothing was blinking.

Too bad I didn’t get a great picture but wait ‘til next year!