Home · Register · Software · Software · Join Upload & Sell

Moderated by: Fred Miranda
Username  

  New fredmiranda.com Mobile Site
  New Feature: SMS Notification alert
  New Feature: Buy & Sell Watchlist
  

FM Forums | Canon Forum | Join Upload & Sell

1       2       3      
4
       5       end
  

canon 2x III owners, are you satisfied?
  
 
Mikehit
Offline
• •
Upload & Sell: On
p.4 #1 · p.4 #1 · canon 2x III owners, are you satisfied?


jcolwell wrote:
You're right, it's the product of the two magnification factors. BTW, the "1.4" is actually the square root of 2, and so two 1.4x extenders makes it exactly 2x.


It depends if the tc is 1.4x or 1.414141414x (the latter is the square root of 2). So 1.4 x 1.4 = 1.96 which accounts for the missing 16mm.....


I had to find some way of avoiding work...



Sep 22, 2017 at 08:41 AM
alundeb
Online
• • • • •
Upload & Sell: On
p.4 #2 · p.4 #2 · canon 2x III owners, are you satisfied?


Mikehit wrote:
It depends if the tc is 1.4x or 1.414141414x (the latter is the square root of 2). So 1.4 x 1.4 = 1.96 which accounts for the missing 16mm.....

I had to find some way of avoiding work...




1.4 and 2.0 are marketing specifications. Actual specifcations are allowed to be +/- 5%. I am not sure about the exact magnification. And it may even vary with focus distance...

I try to work as well, but writing documentation is boring...



Sep 22, 2017 at 08:45 AM
jcolwell
Offline
• • • • • • •
Upload & Sell: On
p.4 #3 · p.4 #3 · canon 2x III owners, are you satisfied?


Mikehit wrote:
It depends if the tc is 1.4x or 1.414141414x (the latter is the square root of 2)....


The square root of two is 1.141421356237...

The square root of two is involved because a 1.4x Extender magnifies the central 1/2 of the area of the image coming from the lens, to fill the normal image field. As a result, the area is doubled, which is associated with an increase of diameter (on which f-stop and etc. are based) by a factor of square root of 2. A 2x Extender magnifies the central 1/4 of the original image, and so the magnification is root(2) * root(2) = 2.0, exactly.



Sep 22, 2017 at 11:45 AM
alundeb
Online
• • • • •
Upload & Sell: On
p.4 #4 · p.4 #4 · canon 2x III owners, are you satisfied?


The square root of 2, to 10 million digits


Sep 22, 2017 at 11:56 AM
molson
Offline
• • • • • •
Upload & Sell: On
p.4 #5 · p.4 #5 · canon 2x III owners, are you satisfied?


therealthings wrote:
I'm looking into getting a 2x converter III for my 600 II. But i'm not sure if it's a good buy. I have seen a few images from Ari and he seems to be ok with it but rather not use it. However, i would like to read more opinions. Please share your thoughts.

Regards,

Marcus


It seemed to work okay for me...





  Canon EOS 5DS R    EF500mm f/4L IS II USM +2x III lens    1000mm    f/8.0    1/13s    100 ISO    0.0 EV  




Sep 22, 2017 at 05:34 PM
speedmaster20d
Offline
• • • •
Upload & Sell: On
p.4 #6 · p.4 #6 · canon 2x III owners, are you satisfied?


therealthings wrote:
I'm looking into getting a 2x converter III for my 600 II. But i'm not sure if it's a good buy. I have seen a few images from Ari and he seems to be ok with it but rather not use it. However, i would like to read more opinions. Please share your thoughts.

Regards,

Marcus


Hi Marcus, I have never said I would rather not use it. In fact I recommend and use it heavily with my 400 DO II, with the 600II I don't find myself needing 1200mm that often but when I do it rocks and it is tack sharp wide open

best




Sep 22, 2017 at 07:48 PM
therealthings
Offline
• • •
Upload & Sell: Off
p.4 #7 · p.4 #7 · canon 2x III owners, are you satisfied?




speedmaster20d wrote:
Hi Marcus, I have never said I would rather not use it. In fact I recommend and use it heavily with my 400 DO II, with the 600II I don't find myself needing 1200mm that often but when I do it rocks and it is tack sharp wide open

best



Hi Ari, i have read 2 posts in the past that suggested you were no fan of using the TC. Here is a quote from Artur Morris website:

Patrick and Arash
Thanks a stack to both Patrick Sparkman and Arash Harzeghi for allowing me to use their great images here. As an aside, I am pretty sure that Arash, with his great concern for extremely sharp fine detail, would rarely if ever use the 2X III TC with his 600II while Patrick often reaches for his 2X. I will be in Patrick’s camp on the 2X.


It is true that you didn't said it and it was Art's assumption. I still have to find the other article. But anyway, i'm happy to read now that you are satisfied with it!



Sep 23, 2017 at 05:49 AM
speedmaster20d
Offline
• • • •
Upload & Sell: On
p.4 #8 · p.4 #8 · canon 2x III owners, are you satisfied?


therealthings wrote:
Hi Ari, i have read 2 posts in the past that suggested you were no fan of using the TC. Here is a quote from Artur Morris website:

Patrick and Arash
Thanks a stack to both Patrick Sparkman and Arash Harzeghi for allowing me to use their great images here. As an aside, I am pretty sure that Arash, with his great concern for extremely sharp fine detail, would rarely if ever use the 2X III TC with his 600II while Patrick often reaches for his 2X. I will be in Patrick’s camp on the 2X.


It is true that you
...Show more



Hi Marcus, that was Artie's opinion not mine. I have said many times that IMO the 2XIII is tack sharp with any of the series II super-telephoto lenses. This is one of the major advantages of the Canon system over its only competition when it comes to these long focal lengths.

here is a 100% unsharpened crop from RAW for example.







Edited on Sep 23, 2017 at 09:51 PM · View previous versions



Sep 23, 2017 at 07:53 PM
Greg Lavaty
Offline
• •
Upload & Sell: Off
p.4 #9 · p.4 #9 · canon 2x III owners, are you satisfied?


Thanks very much for sharing this Ari, that looks about like what I get from mine. At least I feel more comfortable that I'm not doing something wrong.


Sep 23, 2017 at 08:13 PM
therealthings
Offline
• • •
Upload & Sell: Off
p.4 #10 · p.4 #10 · canon 2x III owners, are you satisfied?




speedmaster20d wrote:
Hi Marcus, that was Artie's opinion not mine. I have said many times that IMO the 2XIII is tack sharp with any of the series II super-telephoto lenses. This is one of the major advantages of the Canon system over its only competition when it comes to these long focal lengths.

here is an 100% unsharpened crop for example.


I'm happy you clarified it Ari. And thanks for sharing the crop.



Sep 23, 2017 at 09:26 PM
 

Search in Used Dept. 



armd
Offline
• •
Upload & Sell: On
p.4 #11 · p.4 #11 · canon 2x III owners, are you satisfied?


Ari, have you noticed any issues with pairing the 2x III with a 5dmkiv? I'm wondering if it is a voltage issue but my long lenses are fine de novo or with a 1.4x III - requiring no MA - but with the 2x III, I have to dial in a fair amount of MA and notice more AF inconsistencies.


Sep 25, 2017 at 01:16 PM
Charlie52
Offline
• •
Upload & Sell: On
p.4 #12 · p.4 #12 · canon 2x III owners, are you satisfied?


Same here. I need to do some MA on 2.0 III + 600V2. Just curious what sort of MA did you come up with?


Sep 25, 2017 at 04:15 PM
speedmaster20d
Offline
• • • •
Upload & Sell: On
p.4 #13 · p.4 #13 · canon 2x III owners, are you satisfied?


armd wrote:
Ari, have you noticed any issues with pairing the 2x III with a 5dmkiv? I'm wondering if it is a voltage issue but my long lenses are fine de novo or with a 1.4x III - requiring no MA - but with the 2x III, I have to dial in a fair amount of MA and notice more AF inconsistencies.


Hi,

I don't have any issues with my 5D4 and the 2XIII. I mentioned in my 5D4 review that the AF is very accurate if a bit too slow for my applications. You can try cleaning the contacts on both sides with IPA solution if you think the contacts may be bad.

BTW, most of the time MA is not really needed, when you step up to very long focal lengths like 1200mm there are a number of effects that you have to take into account when assessing the accuracy of the focus. I wrote this article on my blog a while ago that tries to explain some of these issues. For what is worth the MA setting is set to 0 on all of my super-telephoto lenses/TC combinations.


http://arihazeghiphotography.com/blog/focus-micro-adjustment-is-it-always-needed/

hope this helps



Sep 25, 2017 at 05:14 PM
armd
Offline
• •
Upload & Sell: On
p.4 #14 · p.4 #14 · canon 2x III owners, are you satisfied?


Great article Ari and I appreciate your observations about the effects of atmospheric distortion and related issues. If the images were "soft" as you described with no critical focus, one could attribute my findings to distortion however, I've noticed an increasing number of FF images where the AF is clearly on the subject and the area of critical focus is several cm in front of the AF point. When I try static calibration (either LV or MLU/viewfinder) it has a tendency to FF though it's not always consistent - and dialing in MA doesn't seem to solve the problem, making me wonder whether it is an issue with the TC or some voltage issues related to the 5dmkiv? I just sold my 1dx so I can't test the TC on that and the issue occurs on both 5d bodies. Perhaps a trip to CPS is warranted?

Another poster asked how much FF am I dialing in? That's part of the issue, because it doesn't seem to require a consistent amount. Last week it was +1 and then I shot this weekend and the images were FF'ed. I tried calibrating it again and it seemed to be between +3-+5 with variable consistency.

Since I have your ear, do you use mode 3 of IS as Art suggests for BIF handholding/tripod or do you switch back and forth? For anything 600mm and shorter, I'm preferring to handhold when I'm out scouting or on the move and am impressed how good the IS is.



Sep 25, 2017 at 06:30 PM
armd
Offline
• •
Upload & Sell: On
p.4 #15 · p.4 #15 · canon 2x III owners, are you satisfied?


So, here is an example pulled up in DPP, 100% crop demonstrating the FF with the 2x TC III




AF point directly on the back of the little critter. See how the focal plane is several inches in front




Sep 25, 2017 at 09:30 PM
speedmaster20d
Offline
• • • •
Upload & Sell: On
p.4 #16 · p.4 #16 · canon 2x III owners, are you satisfied?


Hi,

A micro-adjustment of +/-1 will not make any difference in the AF accuracy, it is somewhat meaningless as the tolerance of the system is more than 1 unit. To see a meaningful difference you need a value of at least 5 ore more, with smaller values you are just seeing run-to-run noise. The AF system is not perfect and will always show some variation.

As the example above, I am not what can be concluded from it. The subject is too small, doesn't fully fill the AF sensor and is too close to a contrasty BG, it all looks sharp (or sharpened) to my eye and the focus is certainly not several inches away. You need to put your rig on a stable tripod and shoot a larger target placed at 45 degrees relative to the back of the camera so that you can reliably produce and measure a consistent focus shift.... I think your camera and lens are just fine.

I never use mode 3 for IS, the main purpose of IS for HH photography is to stabilize your finder when tracking BIF so mode 3 defeats this purpose (finder remains shaky as IS activates only when you fully press the shutter). I always used mode 2 IS


Hope this helps



Sep 25, 2017 at 10:38 PM
armd
Offline
• •
Upload & Sell: On
p.4 #17 · p.4 #17 · canon 2x III owners, are you satisfied?


Thank you for your insights. This was just an example yesterday when I went out to calibrate the TC to demonstrate what I thought was FF. It was confirmed when I placed it on my tripod and shot the FoCal target - I'm sorry I deleted the target images which placed the MA between +3-+5 (repeated it a couple of times).


Sep 25, 2017 at 10:54 PM
Vancouver47
Offline
• • •
Upload & Sell: On
p.4 #18 · p.4 #18 · canon 2x III owners, are you satisfied?


speedmaster20d wrote:
Hi,

A micro-adjustment of +/-1 will not make any difference in the AF accuracy, it is somewhat meaningless as the tolerance of the system is more than 1 unit. To see a meaningful difference you need a value of at least 5 ore more, with smaller values you are just seeing run-to-run noise. The AF system is not perfect and will always show some variation.


I'm not sure I entirely agree with your tolerance comment. I have set MA with my 1DxII and 600II, bare and with 1.4x and 2x TC's a number of times and end up with exactly the same adjustment number each time.

If the tolerate was as you suggest I would expect some variation in my MA results. However, I have seen some variation in other bodies.



Sep 26, 2017 at 02:11 AM
speedmaster20d
Offline
• • • •
Upload & Sell: On
p.4 #19 · p.4 #19 · canon 2x III owners, are you satisfied?


Vancouver47 wrote:
I'm not sure I entirely agree with your tolerance comment. I have set MA with my 1DxII and 600II, bare and with 1.4x and 2x TC's a number of times and end up with exactly the same adjustment number each time.

If the tolerate was as you suggest I would expect some variation in my MA results. However, I have seen some variation in other bodies.


There is some tolerance in every camera body, no camera is perfect or even near perfect including the 1DXII. I sure wish the focus was dead on 100% of the time but it's not just in case, but If you use software-based focus adjustment it takes multiple readings to average out the noise/variation so it reports the same value every time, but that doesn't mean a small value will make a visual difference in the output. One servo step barely even moves the focus element to make any difference. The only lens that I have MA'ed is my 70-200 f/4 IS, an older lens, and in this case the value is +12 for close range. Everything else I have dialed 0 and it works well for me It's easy to become paranoid with MA

best



Sep 26, 2017 at 02:49 AM
pshyvers
Online

Upload & Sell: Off
p.4 #20 · p.4 #20 · canon 2x III owners, are you satisfied?


It's the old trueness vs precision. If tolerance of focus lock is +/-5 steps, that would be your "precision", and you cannot change it. But your "trueness" you can adjust independently. This would never guarantee a single image would be sharp, but by moving the center of the curve to the right place, you could hypothetically increase your keeper rate.

https://en.wikipedia.org/wiki/Accuracy_and_precision#/media/File:Accuracy_(trueness_and_precision).svg

^ Precision is fixed, it's the tolerance. Trueness is your AFMA adjustment.

Software comes up with a consistent prescription because averaging enough shots finds the center of the PDF.

But, I do completely agree with the paranoid part.



Sep 27, 2017 at 06:46 PM
1       2       3      
4
       5       end






FM Forums | Canon Forum | Join Upload & Sell

1       2       3      
4
       5       end
    
 

You are not logged in. Login or Register

Username     Reset password