April 21, 2014, 03:38:44 AM

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Messages - Steve Todd

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1
For some old west fun, and a great steak at a great price, try Pinnacle Peak Steak House in Trail Dust Town (N.E. Tucson).  And reremember, there is a both a West Saguaro National Park And an East SNP!  They are both excellent.  However, the west side is better for great sunsets! 

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Lenses / Lens Field of View Comparator on Canon DLC Site
« on: March 27, 2014, 09:53:30 AM »
Canon has posted a nifty new lens field of view comparator on their DLC site:


http://www.learn.usa.canon.com/resources/articles/Comparators/fov-comparator.shtml

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Photography Technique / Re: photographing motorsport particularly F1
« on: March 25, 2014, 11:23:59 AM »
Looks like you have gotten a lot of good suggestions/recommendations!  Having shot F-1, Indy Car, German Touring Car, Le Mans, and NASCAR since the late 60's; my only recommendation to add here, is NEVER turn you back to the cars if you are anywhere near the track!  I look back at the shots I took standing on the side of the track (no guard rails or anything between me and the cars) and think, how stupid was that!  Even when shooting from a protected spot, I've still had to duck behind cover to avoid flying stuff!  It's much safer today, but keeping a weary eye out and maintaing spatial awareness of what is happening on the track is still a must!  Best Wishes and be Safe!

4
EOS Bodies / AI Servo AF Versus One-Shot AF For Stationary Subjects
« on: March 25, 2014, 11:05:53 AM »
Having read several posts discussing the pros and cons of using AI Servo AF versus One-Shot AF for stationary subjects, I thought I'd ask the one guy who could best address this issue for us. 

He was kind enought to allow me to post his reply to my questions here:

Hi, Steve:

There are no differences in focusing speed, focusing accuracy, or focusing point selection algorithms between One-Shot AF and AI Servo AF with EOS DIgital SLR cameras, period.

The basic difference between them is that One-Shot AF locks focus as soon as it is complete, whereas AI Servo AF continues to track focus as long as it is active. This is why One-Shot AF is recommended for stationary subjects, while AI Servo AF is recommended for most types of moving subjects, especially those that move towards or away from the camera as opposed to lateral movement across the frame.

There are other differences between One-Shot AF and AI Servo AF that can affect some kinds of photography:

1) AI Servo AF allows photographers to release the shutter at will, regardless of whether focusing has been completed or not. This is intentional, in order to allow the photographer to prioritize capturing the peak moment regardless of focusing status. The trade-off is the fact that there is no guarantee that the focus will be sharp on a stationary subject in AI Servo AF, especially during handheld photography at close range with shallow depth of field. Under these specific conditions (one more time for emphasis, I am saying Stationary Subject, handheld photography at close range with shallow depth of field), One-Shot AF is a more reliable focusing method because it locks focus while AI Servo does not.

2) As light levels diminish, eventually AI Servo AF will cease to function before One-Shot AF does. This is because One-Shot AF allows a longer sampling period for AF measurement in low light than AI Servo does. (The AF measurement sampling period is analogous to a shutter speed for the AF sensor. The longer the sampling period, the greater the sensitivity.) Remember that the AF sensor in the camera has a low light threshold, typically EV -1 or -2 depending on the camera; this figure is quoted specifically for the center AF point with One-Shot AF. It's usually about 2 stops less than than with AI Servo AF, and even lower with off-center focusing points. Therefore, if maximum sensitivity for AF in low light is your priority, we strongly recommend One-Shot AF with the center focusing point.

Going back to point 1, current professional EOS models like the 1D C, 1D X and 5D Mark III give photographers more control over shutter release priority in AI Servo AF than older models. You'll notice that there are menu settings in the AF menu section for 'AI Servo 1st Image Priority' and 'AI Servo 2nd Image Priority.' These settings let you control how long the camera waits before releasing the shutter in AI Servo, which is better than older cameras like the 1D Mark IV or 5D Mark II. But it still lets the camera shoot when it is out of focus in AI Servo AF if you insist. In other words, shutter release in AI Servo AF is always a matter of "when," it is never a matter of "if" the subject is in focus.

The bottom line is simply this: AI Servo AF is *not* equivalent to One-Shot AF for stationary subjects in terms of shutter release priority, especially for handheld shots with shallow depth of field, and we never claimed that it was. That's why we offer both focusing modes.  This doesn't mean that AI Servo *can't* get it right.  It means that One-Shot AF is more reliable under these specific conditions.

Hope that helps.


    Chuck Westfall
Advisor, Technical Information
ITCG Prof Client Relations Division
Canon U.S.A., Inc.
One Canon Park, Melville, NY 11747







5
EOS Bodies / Interesting Read For 1DX and 5D3 Owners
« on: March 24, 2014, 09:40:31 AM »
Interesting read on the 1DX and 5D3 AF Systems.  You might have already read this, but I thought it was worth posting for those who haven't:


http://www.learn.usa.canon.com/resources/articles/2011/1dx_af_precision_crosstype_article.shtml


6
EOS Bodies / Re: EOS-1D X, Dual Back Button AF
« on: March 22, 2014, 11:57:26 AM »
Thanks Viggo for helping Sanj to understand how the method I described works through your great example!  I'd hoped my original post had explained the process.  However, I guess I could have done a better job of explaining it.  That's what happens when you try to describe your thoughts on a technical subject...you know what you want to say, but your explanation doesn't adequately convey your thoughts to others.  Thanks again!  And happy shooting!

7
EOS Bodies / EOS-1D X, Dual Back Button AF
« on: March 09, 2014, 12:38:35 PM »
Having used the back button AF method for several years, I thought I would try the dual back button feature made possible by the recent 2.0.3 firmware update.  Until the new firmware update, I separated the AF Start function from the Shutter Button using the normal back button method.  My focusing method was to have the AF-ON button set for AI-Servo AF.  If I wanted to quickly lock the focus, I would simply focus using AI-Servo AF, release my thumb from the button, reframe the subject and shoot.  I could have just switched between the two modes by pressing the AF Drive button on the top deck and use the Main Dial to switch between One-Shot AF and AI Servo AF.  However, that just wasen't quick enough for my shoot style.

Prior to the new firmware update, you could program one of the programable buttons to toggle between AI-Servo AF and One-Shot AF.  However, that required me to press the button set to toggle between the two AF modes (I used the Multi-function 2 button), with my second finger (middle finger) while using my thumb to press the AF-ON button to focus and my index finger (pointing finger) to release the shutter.  That's not good either.  Sure, I could have also left the shutter button to the default setting (AF and Metering Start-Shutter Release), but I still like separating those functions.

With the new firmware update, you can now program the AF-ON button to AI-Servo and the AE lock button to One-Shot AF.  Once set, they are then dedicated to perform those functions when pressed and held in regardless of what is set on the top LCD panel.  Having used this now for a few weeks, I find it the perfect match for my style of shooting.

To program these functions, use page 343 of the updated EOS-1D X Manual (downloadable from the Canon USA website).  Simply use Custon Function 5 (Operation, Custom Controls) To make the programming changes to the buttons. 

BTW, I programed the MF2 button for Spot AF and the DOF button for AE Lock, as I rarely use the DOF button anyway.  I also program the M-Fn button next to the shutter button for the Viewfinder electronic level function.

Using the two back buttons for instant AF selection and activation, together with the Shutter button only used for metering and shutter release, add a great new operational capability to the already wonderful camera.  I just wish I could setup my 1D4 to do the same!

I realize this was a rather lengthy explanation, but I know I like it spelled out fully when someone suggests a new method to me!  Hope this helps!  It is definitely worth trying!


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EOS Bodies / Re: New EOS-1D X, 4x5 Flipbook Now Available
« on: February 23, 2014, 09:44:13 AM »
You all are most welcome!

I don't remember such publications for 1-Series bodies prior to the 1D4.  Canon did publish an AF Guidebook for the 1DMk IV along with one of their excellent "White Paper" documents.

BTW, the full-size 1DX AF Guidebook that I listed on a previous post is still available at this link:  It's at the bottom of the page as a PDF.

http://www.learn.usa.canon.com/resources/articles/2012/1dx_guidebook.shtml

9
Photography Technique / Re: HDR (and DR) Question
« on: February 22, 2014, 02:16:49 PM »
I'm like you, I just size-up the scene and make my decision based on how much contrast it contains.

I have found that 2-stops works pretty well!  I have shot several hand-held (highest continious shooting speed) in full sunlight that turned out very well when using the "Auto Align" feature in DPP.  However, I would use a tripod and the slow continuous shooting speed setting for scenes with less than full sunlight.

Hope this helps.

10
EOS Bodies / New EOS-1D X, 4x5 Flipbook Now Available
« on: February 22, 2014, 11:57:25 AM »
Use this link to download Canon's new 4"x5" flipbook for the 1DX:

Sorry, here's a better link:   The PDF is at the bottom of the page.

http://www.learn.usa.canon.com/resources/articles/2013/eos1dx_firmware_upgrade.shtml?cm_mmc=EM-_-EO-_-140203-_-Firmware&WT.mc_id=EM1402EO03004&RID=1-G3KRH5&CON=1-CDC-179&PRO=&CID=1-G3AJD5


New photos and simplified explanation of new features contained in the recent firmware 2.0.3 release.

11
EOS Bodies / Canon CPS Irvine Experience
« on: February 16, 2014, 11:36:51 AM »
I have read several posts on CR from people that said they had experienced problems with the Canon Factory Service Center in Irvine, CA.  Well, I don't believe it's just me, but I have never been anything but completely satisfied with the folks at Irvine.  I've used them for over 16-years now and they never fail to amaze me with their excellent customer service, and professional product repair/clean & check procedures. 

Although I live in Albuquerque, New Mexico, I make several trips out to the coast each year.  The Canon Irvine facility is located just 20min. from where my Daughter lives, making it very convenient for me to drop my gear off and get it serviced while I enjoy the great California weather.  Additionally, I save a bunch on shipping and insurance costs this way too!

On my trip out there last week, I needed to have my 1DX and 1D4 bodies cleaned and checked.  The 1D4 also required adjustment, as it took a large amount of MFA (-10 to -16) on most of my telephoto lenses to attain sharp focus!  I had never checked this fully, as I had a second 1D4 that I used almost exclusively and only used wide-angle lenses with this body.  Although the body was obuiously in "as new" condition and the shutter actuation count was exactly 1,000, I was informed that there would be a service fee ($100+) for that body.

Lesson learned, always fully check new bodies thoroughly before the warrantee expires!  Fortunately for me, after reviewing my CPS account and discussing the issue with CPS management, they performed the service at no charge.  Additionally, they completed work on my bodies well ahead of the projected three-day turn around.  They certainly didn't have to do all this for me, but they did!  Just one more example where the Canon Irvine folks went above and beyond for one of their customers.



12
You're most welcome Neuro!

13
The following link will take you to the revised 1DX AF Guide Book: 

http://www.learn.usa.canon.com/resources/articles/2012/1dx_guidebook.shtml

Lots of good stuff per the firmware 2.0.3 update!  PDF to download the guide is at the bottom of the page.

14
EOS Bodies / Best Sensor Cleaning Products
« on: February 06, 2014, 11:14:13 AM »
Although I get two cleaning and function checks each year as part of my CPS membership, I find it's just not enough to keep up with the crud that ends up on my camera sensors.  Even using extreme measures (changing lenses in the car or indoors whenever possible) to keep dust out of the bodies, and blow cleaning, just doesen't cut it!  Although Canon does a good job of cleaning, the hastle of getting the bodies out to them every year is not simple or cheap either!

I'd like to master the art of dry and wet sensor cleaning.  I'm a little reluctant to venture into doing that myself, as I have read of people having to send their cameras to a Canon service center for cleaning or repair after trying to clean their sensors themselves. 

However, I believe many of you sucessfully and routenely clean your sensors yourselves and must have recommendations on what wet and dry (more than just using a blower) methods and products work the best, so any suggestions would be greatly appreciated!  BTW, I have reviewed the methods used on the Lens Rental site, but would still like to hear what has worked for you!

15
Lenses / Re: Review: Canon EOS 100-400 f/4.5-5.6 L IS USM by DxO Mark
« on: January 29, 2014, 10:05:27 AM »
I purchased mine in 1999 after using one of the CPS loaner lenses at the Daytona 500.  It served me well with my EOS-1v film bodies.  However, I have had mixed results with Digital bodies.  It required -15 MA on my 1D4 bodies to be reasonably sharp and when the 1.4x III is add, the results are very disappointing.  On my 1DX body, it required only -2 MA, but still isn't terrific.  However, on my 5DII body (no MA capability) it is pretty sharp?  I like the coverage, but I hope a version "II" is in the works!

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