From time to time, I see an "ERR 99" on the LCD data panel of my EOS Digital SLR. What does it mean?

ERR 99 appears to the user as a non-specific error code which can be caused by a wide range of malfunctions. However, Canon's Factory Service Centers have access to various diagnostic tools that allow them to determine the precise cause of an ERR 99 when it occurs. This makes it relatively easy for them to diagnose problems such as a malfunctioning camera component, but it's not a complete panacea because a variety of problems can be caused by the use of non-Canon accessories such as lenses, memory cards, battery packs, electronic flash units, etc. In cases like these, it is entirely possible that the Service Department won't be able to reproduce the ERR 99 when the accessory that caused it is not present while the equipment is being examined.

ERR 99s are not unique to any specific EOS model. Unless you are a service technician trained to service EOS Digital SLRs, it makes no sense to jump to any conclusions about the cause of an ERR 99 with these cameras. Experiencing error codes is a frustrating experience for any EOS user, but when the objective is getting the problems properly diagnosed and repaired, it is usually best to let the Factory Service Centers do their job.

I own two Speedlite 580EX units and a Speedlite Transmitter ST-E2. Shooting the two flashes indoors never seems to be an issue with the ST-E2 but take it outdoors and communication becomes very inconsistent even when staying within the distance limits as described in the manuals. For example, I shot some team photos last night. The 580s were on light stands 10 feet to the left and right with sensors pointed directly at me. The ST-E2 was on top of my 1D Mark II N --- sometimes both flashes would pop, other times, only one and occasionally neither. Everything set to ETTL on channel A. Should I be using a radio trigger for outdoor shooting? It seems like the only way to get both units to fire with any consistency.

If you want to get the most out of Canon's E-TTL wireless autoflash system when shooting outdoors, I would suggest using Speedlite 580EX or 580EX II as the master unit on the camera instead of Speedlite Transmitter ST-E2. This configuration will provide greater range and consistency in an outdoor set-up. Radio slaves also provide reliable communication, but they don't support E-TTL or E-TTL II.

You kindly answered a color management question for me earlier this year. I now have another. I recently purchased a Canon PIXMA Pro9500 printer. I use Canon DPP software as my RAW converter together with the Easy Photo Print Pro plug in. When opening Easy Photo Print Pro, is the image displayed for print a 'soft proof' that is an accurate representation of how the colors will print? I could not find any documentation that says yes or no to the above.

Did you get a chance to review the online tutorial for Easy Photo Print Pro? It can be downloaded here:

EPPProGuide_v1.3Einch.pdf

There is a lot of useful information in this document. One of the important parts is that if you choose to print directly from DPP software using EPP Pro, the image data can be used "as is" from DPP. Therefore, if you set up color management properly in DPP, you can expect it to be supported in EPP Pro. Color management is fairly straightforward in DPP. You can set the Preferences to use your own custom monitor profile and working color space, and you can also select a printer profile, a CMYK simulation mode, and a rendering intent. Proper adjustment of these settings will allow you to use your calibrated monitor for soft-proofing within DPP. The main tasks that need to be accomplished in EPP Pro are setting the correct paper size, printing layout, and paper in use. Let me know if this answers your question.

I currently own the EOS-1D Mark II and I am strongly looking at getting the EOS-1D Mark III body, which is almost my dream camera. There is ONE feature that so far NONE of the xD xxD or xxxD series of cameras have that my old EOS-1N RS had, which is the Pellicle Mirror. Is there a "D" series camera with that feature anywhere in the future? I know the EOS-1D Mark III is fast enough not to need one, but I'd prefer a camera that didn't sound like a machine gun while shooting fairly quiet dance routines. Also, I'm sure that not having a moving mirror would save some battery power, possibly save a few grams of weight, and make the camera slightly less complex. Some people might say that a mirror will lose about 2/3rds of a stop, but I would assume that the electronics can adjust for that difference.

When answering this same question about a year and a half ago in an earlier edition of Tech Tips (February 2006), I commented as follows:

"Pellicle mirror versions of any EOS Digital SLR are technically possible, but customer demand for them has not been overwhelming so far. I'm sure that Canon Inc. would consider them more seriously if more photographers started requesting them."

I haven't seen much evidence of increased customer demand for an EOS Digital SLR with a pellicle mirror since then, but recent models like the EOS-1D Mark III and the EOS 40D have come up with something called Live View mode that may be even better for some applications. Like a pellicle mirror camera, Live View mode does not use a moving mirror during its operation. This makes the camera quieter during burst mode shooting. However, unlike a pellicle mirror camera, there is no light loss in Live View mode. This provides potentially better image quality by eliminating the need for exposure compensation. Pellicle mirror cameras still have some advantages compared to Live View mode, such as the ability to see the subject during the exposure and the ability to use the camera's AF system. Therefore, it wouldn't make sense to rule out the possibility that Canon or some other manufacturer may eventually offer one. But I would suspect that we're likely to see further development of Live View mode to address its current shortcomings, which may eliminate the need for a pellicle mirror camera. Please note, this is strictly my personal opinion.

I've stumbled upon a technical question I think you may be able to help me with. A friend who is selling a used Canon DSLR claims that using slower shutter speeds (below 1/100) increases the shutter's longevity, or at least claims that using high shutter speeds decreases the shutter's durability. I disagreed and argued that the number of shutter actuations is the same and that the shutter speed used is irrelevant. Could you settle this argument for us and let me know if shutter longevity is affected by the shutter speeds used?

With a focal plane shutter camera, shutter life is not affected by the shutter speed in use. This is because the travel times for the first and second shutter curtains are always exactly the same at every shutter speed, thus there is no difference in stress on the shutter mechanism simply by changing the shutter speed. However, shutter life can be affected to some degree by the framing rate, in other words, the number of frames per second. Every time the shutter is cocked, a mechanical spring must be wound, and this moving part is subject to deterioration over time through normal wear and tear. Generally speaking, shutters in modern SLR cameras will last longest if the camera is set for single frame advance rather than motor-driven continuous sequences.

Chuck, I really enjoy your Tech Tips column (and I'm not even a Canon shooter). Last month's question about low-light focus made me wonder whether sonar focus (which I think Polaroid used at one time) might be a better choice for "cave" photographers. If you could focus by sonar you could also set the flash by the distance information and require no pre-flash, thus making fast and accurate flash shooting in conditions that are iffy with today's equipment. Sonar ranging apparently works well. What is the possibility of marrying it into a future version of some pro-rank camera?

As you point out, sonar focusing has some advantages over the phase detection AF systems used in most current SLR cameras. I'm sure the technology could be adopted for SLRs, but there would be several obstacles to overcome. These would include limiting the measurement area, while at the same time being able to deal with distant subjects or even near ones that don't reflect sound energy very well if at all. I am in favor of any technology that advances the state of the art in autofocusing, but I'm not sure if sonar meets that challenge.

It seems clear that Canon EF-S lenses have been made for small sensor cameras like the EOS 30D to get the best pictures out of them... but is that really true? To make my point clear, if I have a 30D, will I get better image quality with an EF-S lens (like the EF-S17-85 f/4-5.6 IS ) or with an L-series lens like the EF24-105 f/4L IS? If I'm better off with an L-series lens could you explain why?

In many cases, Canon tries to offer users a choice of "good, better, or best" in SLR lenses, especially at the most popular focal lengths. When it comes to standard zoom lenses for EOS Digital SLRs with APS-C sensors, such as the Digital Rebel series as well as the 20D, 30D, and 40D, there are 3 Canon lenses that fit this description:

EF-S 18-55mm f/3.5-5.6 II (Good)
EF-S 17-85mm f/4-5.6 IS USM (Better)
EF-S 17-55mm f/2.8 IS USM (Best)

As you might expect, not only are there differences in specifications like focal length range and maximum aperture, but there are also differences in terms of image quality and price. Concentrating on price for the moment, the EF-S 18-55mm lens is bundled with certain EOS DSLRs at a retail of $100 more than the body only price. The EF-S 17-85mm lens retails for about $499 at many popular retailers, while the EF-S 17-55mm lens retails for about $999 at the same locations.

With a retail price that's twice as much as the EF-S 17-85mm lens, it's easy to understand that the EF-S 17-55mm lens is not only faster but sharper. However, the EF-S 17-85mm lens is no slouch in terms of image quality. If you want to get an appreciation for the differences between the two lenses, I would suggest that you check out the test reports at SLRGEAR.COM:

http://www.slrgear.com/reviews/showproduct.php/product/353/cat/11

http://www.slrgear.com/reviews/showproduct.php/product/136/cat/11

These are good tests in the respect that they analyze not only sharpness but also chromatic aberration, vignetting, and distortion. They also show how image quality changes as focal lengths and apertures are varied, which can be very instructive when it comes to picking the right settings for optimum sharpness.

Another good Web site for lens tests is at The Digital Picture.com:

http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx

http://www.the-digital-picture.com/Reviews/Canon-EF-S-17-85mm-f-4-5.6-IS-USM-Lens-Review.aspx

You'll find a different take on both lenses here, with the added attraction of sample images and a very useful "ISO 12233" feature that lets you compare the sharpness of both lenses based on resolution charts. Once again, the 17-55mm lens is the best, but the 17-85mm lens puts in a decent performance. And if you don't mind stopping down to f/8, even the 18-55mm lens is pretty good.

My overall observation on these three lenses is that you get what you pay for. The EF-S 17-85mm lens is well worth its price, but you can buy better lenses if you don't mind spending more money.

The EF 24-105mm f/4L IS USM, being an "L" lens, falls into the same "best" category as the EF-S 17-55mm f/2.8 IS USM, with the main differences being a different focal length range and full-frame coverage. So, it's reasonable to say the EF 24-105 L IS is a better lens than the EF 17-85mm IS, but a more apt comparison lens for the EF 24-105L IS would be the EF-S 17-55mm f/2.8 IS USM. In this comparison, image quality and cost are quite similar between the two lenses. If you're an EOS 20D, 30D, 40D or Digital Rebel user, choosing between the two becomes a matter of personal preference in terms of focal length range and maximum aperture.

Thanks for reading Tech Tips! That’s it for now. See you in October!

You are invited to submit questions about photo equipment, imaging technology, or photo industry trends that may have a bearing on your work or interests. I cannot promise to answer everything, but I pledge to do my best to address the issues that concern you. (Please use the e-mail link provided at the end of this article.)