Disqus - Latest Comments for Chuck_Westfall

Re: The end of onion-ring bokeh? Panasonic beats the curse of aspheric lenses

Chuck_Westfall — Fri, 02 May 2014 13:59:33 -0000

Strictly speaking, the world's first aspherical lens for SLR cameras was the OP Fisheye-Nikkor 10mm f/5.6. It was announced in 1968 and discontinued in 1976. However, the rear element of that lens extended so deeply into the camera body that it could only be used with the camera's reflex mirror locked up. It was also a manual diaphragm lens. Canon introduced the FD 55mm f/1.2 AL lens with a ground and polished aspherical element in March, 1971: It was the world's first interchangeable aspherical lens for SLR cameras that supported both reflex viewing and automatic diaphragm operation.

http://www.canon.com/camera...

Canon also developed glass molded aspherical lenses for SLRs as early as 1985, and followed that up with replica-type aspherical lenses (a molded aspherical coating bonded to a conventional spherical glass element) in the 1990s.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Wed, 15 Sep 2010 17:34:54 -0000

Kris,

Feel free to post your suggestions here. Constructive suggestions from this web site are forwarded to Canon R&D for their consideration.

The EOS-1D Mark IV has the ability to shut off its top dial during camera operation, but the 5D Mark II does not. I'll be happy to pass along your request for that feature, but if you want to be practical about it in the meantime, tape the dial to prevent it from moving once it's been set.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Wed, 14 Jul 2010 14:05:29 -0000

That's going to be up to Dirck Halstead, the founder of this web site. Please keep checking the home page of The Digital Journalist for updates. Meanwhile, you can continue posting questions here.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Wed, 14 Jul 2010 14:00:09 -0000

Hi, DeeDee:

On your first question, I would suggest using a soft, clean, paper towel to remove most of the water droplets. To avoid scratches, don't rub too hard. Your objective here is to let the paper towel absorb most of the water, understanding that there may be some moisture left over. Then use a clean, dry microfiber cloth to remove any residual moisture. If there's any "schmutz" on the viewfinder eyepiece, clean it off with a q-tip moistened (not saturated) with lens cleaning fluid, then use an air syringe to blow away any remaining fibers or lint. Before storing the camera, I would suggest removing the lens and checking the lens mount area to see if there's any moisture that needs to be removed before attaching a body cap. I would also suggest removing the battery pack and cleaning the periphery of the battery compartment and its cover. Last but not least, remove the rubber cap that covers the Extension System Terminal (see page 17 in the 5D Mark II instructions for location on the bottom of the camera), and make sure there isn't any moisture there either.

On question 2b, you can use the same basic techniques (paper towel first, then microfiber cloth) for cleaning the lens barrel, but use standard lens cleaning techniques for cleaning the filter or front element of the lens.

On question 2a, there is no published specification for how much rain a given lens can tolerate, but generally speaking, lenses like the EF 300/4L IS USM and EF 400/5.6L USM that were introduced before Canon started making L-series lenses with mount gaskets can still be used safely for short periods of time in light rain. However, if you plan on shooting in the rain with these lenses, especially for hours on end, I would strongly recommend covering at least the lens barrel if not the entire camera with a plastic bag secured by a strong rubber band. You should also use a high-quality UV or clear screw-in filter to protect the front element, and I would also recommend extending the lens hood in an effort to prevent image degradation caused by water droplets landing on the filter or front element. It should go without saying that you should avoid changing lenses, memory cards or battery packs while shooting in the rain, but I'll say it here just as a reminder.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 11 Jun 2010 09:18:31 -0000

If it turns out that individual calibrations are required for different focal lengths on a zoom lens, those calibrations are done on the lens itself, not the camera body. However, Canon's camera service technicians have many more AF calibration methods for EOS cameras at their disposal than just the user-accessible AF Microadjustment feature. For example, they can calibrate AF points individually. They can also check and adjust, when necessary, mechanical components such as the reflex mirror and submirror assemblies, whose alignment is critical to AF performance. They can also check and adjust the distance from the lens mount to the focal plane, and make sure that both of those components are truly parallel to each other.

In this case, though, the bottom line is that when an AF calibration problem can be isolated to a specific camera/lens combination, it's best to analyze both components at the same time to ensure proper performance.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Wed, 12 May 2010 09:38:24 -0000

Dear Mr. Beierlein:

I will pass along your report to Canon Inc. for their consideration. Thanks for bringing it to my attention!

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Tue, 04 May 2010 09:41:47 -0000

It's hard to say at this point. My best suggestion would be to check the home page of this web site for updates on its status. Meanwhile, you can submit equipment questions or comments at another web site where I participate:

http://www.prophotohome.com...

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Thu, 25 Mar 2010 23:44:11 -0000

Clearly, the main target of the 2.0.3/2.0.4 firmware update for the 5D Mark II was the enhancement of the camera's video functions. From that perspective, it's a huge improvement on earlier versions. There has been no official comment from Canon Inc. concerning the absence of other user-requested features, but 5D Mark II owners can upload peripheral illumination correction data for new EF lenses such as the EF100mm f/2.8L Macro IS USM lens through the latest version of EOS Utility software. EU 2.8 is now available as a software update through Canon U.S.A.'s web site:

http://www.usa.canon.com/co...

Be sure to specify your OS in the pulldown menu on the Drivers & Downloads tab to see the list of available software updates. You can also download a manual for EU 2.8 if you need to see how to upload peripheral illumination correction data to your camera.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Thu, 18 Mar 2010 11:50:08 -0000

If the EOS Digital Rebel/300D Digital is operating normally, its image sensor is covered by the camera's focal plane shutter when the lens is removed from the body, unless the camera has been set for sensor cleaning. In that case, the mirror flips up and the shutter opens to expose the sensor when the SET button is pressed.

What you may be seeing when you lift the main reflex mirror is the sub-mirror that's positioned behind it. That is a completely different component than the focal plane shutter, which is located at the rear of the mirror chamber.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 12 Mar 2010 11:40:42 -0000

The EOS 5D Mark II was designed earlier than the 7D, 1D Mark IV and Rebel T2i, and its chip set does not support framing rates higher than 30 fps. I would suggest that you should not anticipate seeing 60 fps frame rates made available for the 5D Mark II.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 01 Mar 2010 10:33:00 -0000

Hi, John:

I'll be happy to pass along your request to Canon Inc. R&D. In the meantime, if you want more protection than the standard rear lens cap offers, your best bet is to improvise. One way of doing that is to wrap your lenses with a soft protective cloth, or in some cases you can use a soft lens pouch to accomplish the same thing. Enter "Domke Lens Wrap" into your favorite search engine to see some examples of the wrappers I'm talking about.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 22 Feb 2010 13:22:31 -0000

Hi, John:

I sincerely appreciate your interest, but I cannot comment on Canon's future plans or products. Thanks for reading Tech Tips!

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Tue, 16 Feb 2010 10:39:35 -0000

Hi, Phil:

If the lens distance range setting is not the issue, the next thing to check is the orientation of the focusing point you were using relative to the subject contrast. Keep in mind that all of the off-center focusing points on the 5D Mark II are single-axis rather than cross-type. They cannot AF on subject contrast that is parallel to their orientation. To see an illustration of these points, please refer to page 32 of the EOS 5D Mark II/50D white paper document, available here:

http://www.usa.canon.com/dl...

If you're having difficulty using an off-center focusing point with the 5D Mark II, try turning the camera sideways to change the orientation of the focusing point relative to the subject. Also, when photographing low-contrast subject matter like human skin, sometimes it's better to focus on the edge of the face rather than placing the focusing point completely on the skin.

Hope that helps!

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 12 Feb 2010 15:09:55 -0000

Hi, James:

I wouldn't put it quite that way, but there's a pretty good possibility you'll soon be seeing some comments from working pros who've used the 1D Mark IV recently.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 12 Feb 2010 15:05:17 -0000

Hi, Phil:

Before you send the 70-200 in for service, take a quick look at the focusing distance range switch on the side of the lens. It's possible that it may have been set for a minimum focusing distance of 2.5 meters (approx. 8.25 feet) rather than 1.4 meters (approx. 4.6 feet). If so, you wouldn't have been able to autofocus on a subject closer than 2.5 meters. As you know, the 28-70L lens has no such switch.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Tue, 09 Feb 2010 18:20:59 -0000

Thanks for the information, Eric. Did you happen to notice the battery charge level on the camera when these instances occurred? Also, are you using the accessory battery grip? If there's a temporary loss of electrical contact or the battery charge level is extremely low, there's a possibility that the camera could essentially "reboot," causing the sensor cleaning mechanism to activate.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Tue, 09 Feb 2010 14:35:51 -0000

Hi, Patrick: Please see my replies to Dan. Your input is appreciated!

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Tue, 09 Feb 2010 14:34:01 -0000

Hi, Dan: I've now read the forum thread you referenced, and it appears to me that reactions to the performance of the EOS-1D Mark IV with Firmware 1.0.6 are decidedly mixed, at least in that particular group of users. Some are perfectly happy with the new firmware, while others are not. Canon is monitoring many web forums for additional user comments, and I would anticipate that there will be further input from professional photographers covering major sports events like the Super Bowl and the Winter Olympics. Canon will be in a better position to determine if there is any need for further firmware updates once this input has been gathered. Thanks for your report!

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 08 Feb 2010 14:23:19 -0000

Hi, Dan:

In the process of updating my laptop a couple of weeks ago, our IT Department inadvertently messed up my remote access to e-mail. As a result, I did not receive anything from you last week while I was out of the office on a business trip. I'm back now, but the bottom line is, I haven't had time to read your information yet and probably won't be able to get to it until later on this afternoon. Sorry if that's not soon enough for you.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 08 Feb 2010 11:01:53 -0000

When the firmware update for the 5D Mark II was announced on October 20, 2009 Canon clearly stated that it would be released during the 1st Half of 2010. The release schedule is still on target.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 08 Feb 2010 10:09:41 -0000

Hi, Dan & Patrick:

If you are unhappy with the performance of firmware 1.0.6, I would suggest that you contact Canon's Service Department.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Mon, 08 Feb 2010 09:33:06 -0000

>>I assume that the flash output is calculated based on that [distance] data.<<

Not necessarily. When the flash head is aimed directly at the subject, distance data is compared to preflash illumination reflected from the subject as well as several other factors. The E-TTL II algorithm calculates flash output based on analysis of all these factors.

>>If the focusing ring doesn’t show accurate distance, what distance the camera takes into account in E-TTL II?<<

The distance data used by E-TTL II is supplied by a distance encoder inside the lens that's not visible to the user. This encoder has finer resolution than the scale printed on the lens.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 22 Jan 2010 11:58:17 -0000

Thanks again for clarifying your concerns. You have some interesting preferences!

If I understand you correctly, are you suggesting that Canon should allow users to reconfigure the RAW+JPEG and Picture Style buttons? If so, what else do you suggest?

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 22 Jan 2010 10:51:41 -0000

It might take a bit of practice to adjust to the control layout I've suggested, but the DOF preview button on the camera body is definitely accessible with the middle finger of your left hand even when the camera is held vertically with BG-E7 attached. The only missing feature at that point is switching to a registered AF point by pressing a button, which you did not mention in your original inquiry. You can still select a focusing point with the multi-controller, though.

Thanks for the comments and suggestions about additional custom configurations. I'll be happy to pass them along to Canon's R&D group.

Re: Tech Tips - The Digital Journalist

Chuck_Westfall — Fri, 22 Jan 2010 09:31:43 -0000

Hi, Joseph:

Have you tried configuring the AE lock button as your FEL button? That would allow you to retain viewfinder electronic level control through the M.Fn button and AF stop through the AF-ON button. If you still need standard AE lock, you could configure the DOF preview button to provide that feature.