Monday, January 28, 2008

Cable Release for the G9

My Canon G3 (yes, G3) came with a wireless remote and even though it was not used a lot, it sometimes came in handy. The remote was useful enough that when it broke, I bought a generic substitute. The G9 has no such remote – wireless or otherwise. That is, the G9 had nothing until Richard Franiec took on the challenge of making a mechanical cable release adapter. Right, a mechanical cable release!

Richard’s design is amazing simple. His adapter, precision machined of black Delrin, simply snaps onto the shutter release of the G9 (and G7). Well, actually there is no “snap” -- more like a push. Screw in that old cable release (you did keep it, didn’t you?) and you’re ready to trigger the G9 without touching it.

If you’ve lost your old release (or never had one), you can get a new one for about $15 to $25 depending on length. Typically, cable lengths are about 10 to 20 inches but some are up to 60 inches. There are even pneumatic versions up to 20 feet long!

Before getting Richard’s “Custom Mechanical Cable Release Adapter” (no wonder he calls it CMCRA), I used the two second delay to trigger the G9 when it was fixed on a tripod. The two second delay works very well but the cable release just feels more natural.

Richard has other products for the G9; I use them all.

For more information about Richard’s accessories for the Canon G7 and G9, check MyCanonG7, Kleptography or contact Richard directly at

Sunday, January 27, 2008

An Overview of JPEG

A previous post introduced the basic ideas of raw and JPEG image files. This post is about JPEG. I’m no expert on JPEG so my understanding and the following explanation is probably an oversimplification but, even so, may be a useful starting point for many new photographers.

Most of the pictures that we see every day were made from JPEG files. Almost every picture on the Internet is a JPEG. The photo sharing websites require or prefer JPEGs. The local discount digital photo printshop requires JPEGs. Many photo contests and online galleries require JPEG files. Your digital camera – even if it is an expensive DSLR – shoots JPEGs and probably defaults to JPEGs; in fact, your digicam may shoot only in JPEG mode. Photojournalists are likely to be required to shoot in JPEG mode. The micro-stock agencies post JPEG images for downloading. So, what is a JPEG?

Instead of going into the full definition of JPEG with all the mathematical details and possible variations, for our purposes there are three important features of a JPEG file: 1) JPEG is a data file for storing digital images, 2) JPEG is an 8 bit data file and 3) JPEG is a lossy data file.

In computerspeak, current digital cameras can capture 10, 12 or even 14 bits of information from every pixel. When this captured information is to be stored in an 8 bit data file, some of it must be discarded. Even without going into all the details of “bits” the intuitive conclusion is correct: A JPEG data file does not contain all the information originally captured by the camera. This is troublesome to some people; however, monitors and printers are actually 8 bit devices.

Instead of storing all the 8 bit data, the size (and quality) of the JPEG data file is further reduced by discarding data that might not be noticable to the human eye or interpretation. This is called “lossy” compression and is an ingenious method of reducing file sizes. Before the image is saved to the JPEG data file, a “quality” is specified. At the highest quality, very little data is discarded. In Photoshop, JPEG quality is specified from 1 (lowest quality) to 12 (highest quality). The first image shown in this posting was saved at a Photoshop quality of 1; its file size is 34 KB. This image was saved at 6; its file size is 70 KB (click for a larger image). These images are 100% crops based on the in-camera JPEG taken at the same time as this previously shown raw capture from this photo.

Obviously, a JPEG image file is extremely useful. We all benefit from JPEG. In the next posting, I’ll give an overview of the JPEG image files and options for the Canon G9 .


Thursday, January 24, 2008

G9 vs Leica M8?

A fun read and excellent article about a user's experience with the Canon G9 is currently posted on my favorite website, Luminous Landscape.

Wednesday, January 23, 2008

G9: In the Raw and/or JPEG

Shortly after pressing that shutter button, the internal computer chip in your digital camera begins to process the data collected by the sensor and then saves that data as a “picture” in the form of a data file on the memory card. Most likely, that data file is either a JPEG or a raw file format. JPEG is an acronym for Joint Photograpic Experts Group . JPEG files have “jpg” as the filename extension; for example, myfile.jpg is the filename of a JPEG image. Whereas JPEG files follow international standards, a raw file is proprietary to the particular camera manufacturer according to their needs. Therefore, many devices have software to read and process JPEG images but few can deal with raw images because all the raw image files are different.

In the case of the Canon G9, the raw image files have the filename extension cr2; for example, myfile.cr2 is (probably) a Canon raw image file. However, just because the filename has the .cr2 extension does not necessarily mean that it came from a Canon G9 camera because all the current Canon cameras having raw capability save their raw images with a cr2 filename extension. My G3 used a crw filename extension.

So, what’s the difference between JPEG and raw and why worry about it? Well, there is – or can be – a lot of difference but you don’t have to worry about it unless you want to. On the other hand, if you are concerned about maximizing image quality, developing a personal or customized look and generally pushing the limits of photography, then you should learn to process raw image files. The raw image file is sometimes described as the digital version of a (film) negative whereas the JPEG image coming straight out of the camera is more like a machine processed print from that negative. Although debatable and not strictly true, this description and comparison is easily understood. This picture is a 100% crop (click for larger view) from the raw file of a previously used scene; it has had no (as far as I can tell) post processing. Kind of ugly, fuzzy and noisy, isn't it?

It is very important to realize that your camera makes its JPEG from the raw data in about a second or so. I call this image the "in-camera" JPEG. You can make your own JPEG from the raw file by using any editor that can read the proprietary raw file. This is what I do; of course, it takes me quite a bit longer than one second. So, most of the time, my final product is a JPEG file and, for my best efforts, a print made from that JPEG file.

One advantage of learning about raw image processing is that you are then entitled to participate in the endless debates about whether raw or JPEG is “best” or, for that matter, even worthwhile. In the great raw vs JPEG debate, when someone states that they've thoroughly investigated, studied and tested to come to the conclusion that JPEG is "good enough" or that their own JPEGs are "as good as" their own raw post processed images then I believe them. When someone states that they get better results using raw and post processing (my own experience) then I believe them as well.

(This is another post that will be continued and also used as a reference and link).

Friday, January 18, 2008

G9: Flash with Gadgets

The G9 accepts external flash and that means: Gadgets! Photographers seem to love flash gadgets. I have several and want more because they promise to solve my flash problems. But which gadget to get next? Which of the gadgets that I already have is actually the best?

Time for a little testing: G9, Canon 580EX, various attachments, a simple scene in a small bedroom. For consistency, do as many do and set the camera on Program Mode, low ISO (100), auto white balance, flash set at ETTL, use the in-camera jpg without any additional processing.

Rounding up the usual suspects, I arranged them so that some shadows would be cast on the walls. Here’s the first shot. The flash was provided from the built-in flash on the G9. Not too bad – better than I expected! Shadows are hard but almost hidden because the subjects are at approximately the same height as the flash. Exposure seems OK but the histogram indicates (to me) about one stop underexposed. The wall on the right is a little bit bright. No red eye! Let’s try the big flash.

With the Canon 580EX mounted on the G9 and pointed directly at the subject, the result is about the same as using the built-in flash. The 580EX sits high on top of the G9 so the shadows have dropped a little and are more visible. The wall on the right is still a bit bright. The histogram still indicates underexposure – a little less than one stop. Time for a bounce.

This picture was taken with the 580EX pointed straight up at the ceiling. Lots of differences here. The color is a bit off; oh yeah, the ceiling really isn’t white. It’s a kind of creamy color; like the walls but lighter. Shadows are almost gone. I like this but would have to change the color balance (good thing I shot in raw + jpg). The histogram still indicates underexposure. There’s a little white card on the 580EX for directing some of the bounce flash forward, time to pull it out.

The little white card on the 580EX is intriguing. At first glance, there’s no difference between this picture, made with the white card extended, and the previous one. Take a closer look. There’s a little more shadow just behind Elmo. How about that -- that little card really does work!

With the background work done, it’s time for a gadget! Many people swear by the simple Sto-Fen attachment. I’ve had one for years but use it infrequently because it really seems to eat light. The Sto-Fen must be ordered specifically for a particular flash but once you get the right one (and heat it with a hair dryer to expand it the first time) it slides easily onto the 580EX thereafter. For this shot , the 580EX, with the Sto-Fen, was pointed straight up. Well, look at this! The Sto-Fen creates harsher shadows than the simple bounce flash! Or did it? The shadow behind Elmo is more visible but the shadow from the headboard at the extreme right has almost disappeared. Some describe the Sto-Fen as producing a “bare bulb” effect by casting light all over the room. The colors are perhaps a little better. The histogram still indicates about the same underexposure – perhaps a little better.

Some photographers use the Sto-Fen at a 45 degree angle instead of pointed straight up. Here's that variation. With the Sto-Fen (really the flash head) at a 45 degree angle, the shadows look a little more harsh to me. Still underexposed according to the histogram. I don’t see a benefit here (mental note: point the Sto-Fen up).

The Lumiquest Pocket Bouncer reminds me of a big white card attached to the flash head. In fact, many photographers make their own. With the flash head pointed straight up, the main panel of the Pocket Bouncer is at roughly a 45 degree angle. Well, this is interesting. Using the Pocket Bouncer, the shadow is still behind Elmo and the histogram still indicates underexposure. The color balance has shifted and is a little better – probably because less light is being bounced around off those cream colored walls and ceiling. Not exactly what I was hoping for. In the future, I won’t be embarrassed by using the big Pocket Bouncer on top of the huge 580EX on top of the little G9.

The underexposure, apparent with every gadget and even with direct flash, did not surprise me. For all shots, the little white bunny was the focus point and therefore the ETTL information was taken there. But it seems to me that the Canon ETTL system almost always underexposes. This feeling goes back to the 380EX, 420EX, a Canon film SLR and my Canon G3. Many others seem to feel the same way (although some disagree). Therefore, except for this demonstration, I almost always increase the flash exposure compensation when using a Canon flash in ETTL mode. Up to this point, I’ve liked the simple bounce flash with white card extended, so here’s another one with that setup but with +1 flash exposure compensation. (Uhh, this one is actually a little overexposed but I’ll leave it in the posting to show humility and, besides, I’d already taken down the scene. )

Although all the above pictures are directly from the in-camera jpg, the G9 was actually set for raw + jpg. Next, I examined every raw file to see what else could be learned.

First of all, using Adobe Camera Raw (ACR) to process the raw files, I changed the white balance to “flash” instead of “auto”. For all the pictures, this essentially corrected the colors. Of course, the G9 could have been set for “flash” white balance (instead of auto) in the first place and the in-camera jpgs would have turned out OK.

What about the exposure? Based on the ACR automatic exposure adjustment, the built-in G9 flash underexposed this particular scene by about ¾ stop. The Lumiquest underexposed it by about ½ stop. All other configurations were underexposed by about ¼ stop. So my interpretation of the histogram and resulting flash exposure compensation was indeed off. A better adjustment would have been be to add about ½ stop of flash exposure instead of the one full stop that I added in the final picture. Even so, my +1 stop adjustment was OK according to ACR! In addition to the automatic exposure adjustment, ACR attempts to recover “overexposed” highlights. For that last shot, ACR did not adjust the “exposure” but did change the “recovery” and “brightness” settings.

So I like this one the best; it’s the raw conversion of the previous shot (bounce, card extended, +1 flash exposure, auto process in ACR from raw).

Lessons learned: Most of the time the basic bounce flash, perhaps with the white card extended, produces the most pleasing results for my tastes. Add about ½ stop of flash exposure compensation when using the Canon flash in ETTL mode. Conduct some additional testing out-of-doors; perhaps the Pocket Bouncer might prove more beneficial out-of-doors or in a large room. Continue to shoot in raw mode.

Note: Your own interpretation, tastes, preferences and mileage may vary considerably. These are easy tests to do. The results and conclusions could easily change with the subject and room size. Give it a try and let me know your conclusions.

(But I’ve just heard that good results can be achieved by making a diffuser from a one gallon milk jug placed on top of the flash, so ….)

Saturday, January 12, 2008

2007 in Review

This is my belated attempt to close out 2007 and begin 2008. LightDescription began just over a year ago ( as my platform for commenting on photography, posting photographs and learning about blogging. It has served that purpose well and I intend to continue the effort.

For the first nine months of 2007, LightDescription had only a few visits each day. In September, I became active in the special purpose website, MyCanonG7, as well as several photography discussion forums. In particular, with my interest in the Canon G series of cameras rekindled and with favorable publicity from MyCanonG7, LightDescription began to receive many more daily hits. For the calendar year, LightDescription had over eleven thousand hits from more than seven thousand visitors. Not too bad for the first year!

The MyCanonG7 website has been reformatted and reformulated to be less specific to the Canon G series cameras. Because I recently bought a Canon G9 camera, I’ve been blogging mostly about my efforts to learn and maximize the performance of the Canon G9. This theme will continue for a while and since the G9 is such a neat little camera I’ll be using it frequently to make a point (or, more likely, to show off!).

In 2007, impressed by an essay of Mike Johnston’s, I made a personal portfolio of my best photographic efforts prior to 2007. This past week, I’ve been reviewing my photos from 2007. Frankly, even after much study and effort, my 2007 portfolio is not the equal of my lifetime portfolio but, I suppose, that’s to be expected. Still, my 2007 portfolio has some nice shots and particularly so of family. I am becoming a better photographer.

The introductory shot above is one of my better ones from 2007. It might even make the cut for the lifetime portfolio. But my favorite is of my girls.


Tuesday, January 8, 2008

G9: Flash Sync Speed

How did Elmo get stuck in that tree at night? Well, actually it was mid-day. This photo is an example of overpowering the sun with flash. The day was slightly cloudy but the G9 was set for ISO 80, 1/2500 second, f5.6 in manual exposure mode. Therefore Elmo, the tree and even the sky were significantly underexposed. A Nikon SB-28 was then mounted in the G9 hotshoe and also placed in manual mode at full power to provide “fill” flash. A bit of cloud in the background is still visible.

The G9 is officially described as limited to 1/250 second with external flash; however, it turns out that, if the G9 does not know about the external flash then it will work at higher sync speeds. In fact, the EXIF data for this shot indicates that flash is “off”!

The G9 recognizes Canon flashes but apparently gets confused if non-Canon equipment is attached to the hot shoe. With a Nikon SB-24 or 28 (and probably others, see the compatibility posting) in the hotshoe, the flash is fired regardless of the sync speed. This posting at Strobist explains the details in general.

Prior to photographing Elmo, I did a few experiments with a Nikon SB-28, SB-24 and Vivitar 285HV by shooting in a nearly dark room with the flash in the hot shoe and the G9 in manual mode. The G9 will sync with all these at 1/2500; however, it seems that the SB-28 and SB-24 “lose” the equivalent of about 1-1/2 stops at 1/2500. The Vivitar loses 2 stops. It also seems that this loss of flash efficiency is roughly proportional to shutter speed; that is, the Vivitar loses about 1 stop at 1/1000 second. The light from the flashes seemed evenly distributed even at the high shutter speeds – there was no mechanical obstruction of the light. So these flash units can be used at very high sync speeds but they will appear to be somewhat less powerful.

Note that the G9 does not permit shutter speeds faster than 1/1600 if the aperture is larger than f4.

With a Canon flash (580EX, 420EX or 380EX were tested) mounted in the hotshoe, the G9 resets from 1/500 to 1/250 when in manual exposure mode. The shutter speed is changed whether the flash is in ETTL or manual mode (580EX) unless the Canon flash itself is set to high speed sync mode. (Canon high speed sync is accomplished by pulsing the flash.)

… and I did get Elmo down from the tree after snapping his picture.


Friday, January 4, 2008

G9 Flash List

Matching an external flash to camera is a frequent topic on photography discussion forums. The G9 is so new, so versatile and so small that this question is being asked repeatedly about the G9. It finally occurred to me to address this question in my blog rather than continually attempt to answer individual questions.

The G9 has a hot shoe for external flash and, in general, works well with the Canon ETTL flash system except that ETTL does not work in the G9 Manual mode. Beware: Some Canon flashes and accessories cost nearly as much as the G9! Fortunately, the G9 also works with other flashes – even very inexpensive flashes.

Specifically mentioned in the Canon G9 Manual are: 220EX, 380EX, 420EX, 430EX, 550EX, 580EX, 580EX II (actual functionality varies). I have personally used a 380EX, 420EX and 580EX with my G9. Some examples are here, here and here.

Here is a link to an excellent reference for using Canon flash systems and other flashes on Canon cameras. Much of this information applies to the G9 as well.

I’ve started a G9-flash compatibility list (discussion thread) at

In the list below, I’m relying on personal experience as well as the referenced documentation and discussion for the Canon G7 or G9.

220EX, see
380EX, I have personally used the 380EX with my G9
420EX, I have personally used the 420EX with my G9
430EX, see
580EX, I have personally used the 580EX with my G9

Many non-Canon flashes will also work in some fashion with the G9.

Cowardly Disclaimer: Recent Canon cameras can be damaged by high flash trigger voltage. This is also true of many cameras. Before using older flashes with your new G9, check for compatibility. Here’s one reference:

20, see
28, see
36, see
C 20-C, “Photography with the Canon PowerShot G7”, Siegfried Sierlein, (

I routinely use the Nikon SB-28 on my G9. Although the SB-28 works only in manual mode (or its own auto mode) it is smaller than the Canon 580EX and works well on the G9.
SB-24, I have personally used the Nikon SB-24 with my G9.
SB-28, I have personally used the Nikon SB-28 with my G9.
SB-800, see

Sunpak PZ40X II, see

Be careful here! The exact model number is important!
I have personally used a Vivitar 285HV with my Canon G9. The 285HV is a relativity recent re-design of the old 283/285 Vivitar flashes. The 285HV has the reduced trigger voltage to protect new cameras such as the Canon G9. The old 283/285 may have high trigger voltage and damage the G9.

I hope to update and expand this list, so please participate in the discussion thread or add your comment to this post.