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 on: January 22, 2015, 02:21:37 PM 
Started by Frank Kolwicz - Last post by Frank Kolwicz
It's been a long, downhill, bumpy ride, but I've finally gotten back to where I was before I broke my 600/4(I) a couple of years ago.

The latest batch of images from my fully up-dated hardware now produces more actual in-focus images than I got from the earlier 5dii/EF600-f/4L IS(I)/1.4x system, but not the more than $10K worth more. I would still be using the same Canon crop-sensor bodies as now, but, if only Canon had not refused to repair the optics on that dropped lens, I could have avoided the expense of all those rentals and the new (used) 600IS(II) lens.

The only real benefit I've gotten from that experience and serious expense is a somewhat larger percentage of perfectly focussed images and the loss of about 3 lbs pulling my right shoulder out of joint when I heft the rig up onto my window mount.

Thanks loads, Canon.

 on: January 19, 2015, 08:52:20 PM 
Started by Frank Kolwicz - Last post by Frank Kolwicz
I only photograph birds and only with the 600+1.4x/7dii and 70d and a 100-400L and 70d; I prefer the soft light of overcast skies and often work in the rain, snow, sleet and fog (but not wind). You can see that I have rather demanding conditions and I also expect quality images good enough to make display prints.

I've used 4 or 5 Mark I versions of the 600/4 with a 5dII and I wouldn't say that I have experienced remarkable improvements with the 7dii, in fact I found more variability in resulting images from one sample of lens to another, much more in two cases!

But on the 7dii the ability to select a very small focussing spot is most welcome as my subjects often require picking out the head or eye of a bird when the whole animal only occupies 1/8th of the image area or less at times. With the full-size single square AF box selected, I often can't be sure whether the system is picking up the head or the tail of a bird  and examining the resulting files shows this variability.

On the other hand, the supposed improvement due to the mode 3 setting on the 600/4LIS(II) for moving subjects, much heralded by some reviewers, has been a total disappointment, as has tracking ability with something as simple as an on-coming swimming duck (in mode 3, even allowing for microfocus being slightly off).

Also, on the 7dii I'm disappointed that they didn't include the articulated LCD of the 70d which I find very helpful, along with LiveView, to find birds at extreme high and low angles from my car window (a major reason I bought 2 of them and am keeping one). I've had to buy an angle finder for $250 to do that job with the 7dii and not nearly as well.

Despite everything I've read in reviews, I don't get near-perfect sharpness on 90% of my images, when examined at actual pixels (100% view). It is improved compared to my previous cameras and I guess that's all I can reasonably expect doing birds in Oregon's gloomy winters. I hate the look of flash and would rather miss some good shots than produce lots of ugly ones.

 on: January 19, 2015, 12:13:27 PM 
Started by Frank Kolwicz - Last post by marcfs
Canon new lens and bodies are offering significant improvement over previous equipment.
7 Mark II-  lots of pluses, with focusing speed and accuracy being among them; in this area the 7D Mark II contains Canon’s most advanced focusing system
Long Lenses – again much better than previous models; 100 – 400 Mark II very superior to Version 1
If you have tried any of the other canon Mark II lenses you will experience major improvements.


Marc Schoenholz

 on: January 16, 2015, 05:02:24 PM 
Started by Frank Kolwicz - Last post by Frank Kolwicz
I've been using Canon 5dii and 70d bodies with EF600/4 lenses for birds (different versions over the past some years) and was never all that impressed with AF accuracy, although with enough multiple frames I did get a few acceptable images to be satisfactory. During that time I didn't feel like I should have to spend the big bucks for the top of the line 1 series bodies, that the cheaper, simpler models should suit me well enough.

Canon finally put the better AF system in a body I'm will to pay for, the 7dii, and I was very surprised at the difference it made in accuracy compared to the 70d (+/- 1/3 dof versus 1 dof) with my EF600/4 IS (II).

I suggest that anyone considering a long fast lens also plan on using a body with the better AF system.

 on: January 10, 2015, 11:16:12 PM 
Started by mjperini - Last post by Bob Atkins
Yes, currently  EOS Utility3.x only supports these cameras:

EOS 7D Mark II

I don't know if Canon intend to extend this selection, as they did with DPP 4.0. I know that in the previous version of the EOS Utility they made a big thing out of support for all EOS cameras back to the D30, so they may be planning to extend version 3 to other camera bodies. As far as I know they haven't commented on that, but I may have missed it if they did.

 on: January 09, 2015, 11:44:27 AM 
Started by mjperini - Last post by mjperini
Canon Europe has done a nice article on the new EOS Utility 3,
which has many new features, and new integration with DPP4 as well as wiFi
You can find it Here:

Unfortunately, only the newest Canon cameras are supported.
I use EOS Utility 2 for Tethered shooting with my 1Ds III ,7D, & 40D none of which are supported.

A didappointing trend for free but very useful utility software.
I also saw a note elsewhere that Neither application works with Apple's Yosemite

 on: January 08, 2015, 01:11:21 PM 
Started by KeithB - Last post by KeithB
So the answer is: its complicated.

I guess you can make the image circle any size you want by playing with the lens->sensor distance, which might be the piece I am missing.

 on: January 08, 2015, 01:02:04 AM 
Started by KeithB - Last post by Bob Atkins
Not really. Obviously the larger the sensor the larger the image circle that is required to cover it. However the size of the image circle depends on the lens design. A 20mm f2.8 for a full frame sensor would likely be physically larger than a 20mm f2.8 for an APS-C sensor, but you can't really relate "front element diameter" to "sensor size" or "image circle" in any direct, linear manner. They are not directly proportional. It depends on the lens design and the diameter and position of internal aperture stops (and/or lens elements). You can use smaller diameter lens elements for smaller sensors which require smaller image circles. In theory this should lead to cheaper lenses...

If you scale focal length with sensor size, then a 50/2 APS-C lens needs a front element at least 25mm in diameter, whereas the "equivalent" FF  80/2 lens needs a front element at least 40mm in diameter. For medium and telephoto lenses this holds true, but for very wide angle lenses you can't calculate front element size from focal length and aperture. A 10mm f4 lens is going to be more like 70mm in diameter than the 2.5mm you'd calculate just from dividing the focal length by the aperture.

 on: January 07, 2015, 08:50:05 AM 
Started by KeithB - Last post by KeithB
I guess what I am asking is:
Is there a formula to determine the "correct" size (i.e., size of the image circle) of a set of optics? For example, for my S90 I have a really tiny lens, while my Rebel needs a larger lens, even for the same F stop. To make it concrete, the S-90 has a 6-22.5 mm zoom with an fstop of f/2-f/4.9. An equivalent lens for my rebel, would be huge - probably the size of the EF-S 10-22. Now the EF-S 10-22 should work fine on the S-90, but the S-90 lens would not work on the rebel. Is there a simple formula to determine how "big" a lens needs to be to work on a given sensor size?

 on: January 06, 2015, 02:38:21 PM 
Started by KeithB - Last post by Bob Atkins
It's the image brightness on the film/sensor plane that counts. It doesn't matter whether the sensor sees all of it or just a part if it, the "number of photons per" is the same, so the exposure is the same.

An analogy would be rainfall. If it's raining at 1" per hour, it doesn't matter whether you collect water in a 12" bucket or a 3" cup, you still get 1" per hour.

The larger sensor does capture more light, but it's spread out over a larger area, so the exposure (which depends on light per unit area) is the same as for a smaller sensor which captures less total light, but over a smaller area.

Nothing changes when you use a AFF lens on APS-C. The actual focal length is the same and the aperture is the same. The only thing that actually changes is the angle of view, which can be (and usually is) though of as a change in "effective focal length relative to full frame". Depth of field changes only because of the way it's defined, which is based on a certain print size, not a certain degree of magnification of the original image.

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