# EF24-70 F2.8L MKII soft edges?



## LesC (May 11, 2017)

I've had my EF24-70 F2.8L MKII lens for about 2 1/2 years now and I've never been convinced it's a stunning as reviews suggest it is. It's permanently fitted to my EOS 6D and having been into photography for 25years + I like to think I know the technique side of thing at least (but happy to stand corrected)

I've had some very sharp images from it but now and again I'll get some such as the example below that just look soft at the edges. Performance seems to be inconsistent but I can't nail it down to any particular settings ie certain focal lengths, F stop etc.

I'll admit that at fullscreen on my 24" monitor photos such as the example below look fine; it's only at say over 50% and particularly at 100% that the softness really shows. I'd just like to gauge if there is something wrong with the lens, my technique or if I'm just expecting too much? I've had some shots taken with the humble EOS100D (SL1) + 18-135 lens that have _seemed_ sharper although admittedly although I've not done any scientific tests on identical scenes and the sensor has a smaller pixel count so at 100% appears smaller on screen that shots from the 6D.

I should add that I've sent sample shots to both my (well respected) camera dealer & to Canon who both felt it was OK and last year the lens was checked by Canon for sharpness/alignment when it went in to have filter thread replaced after a knock. It was passed as OK and indeed I've had some lovely sharp images from it since.

So on to the sample images & selected crops. It was taken in woods around midday on a cloudy day at focal length of 55mm @ F16, shutter speed of 2 secs, ISO 100. Lee landscape polariser fitter & camera was tripod mounted with cable release used. There was a light breeze hence movement in the foliage but no where near enough to move the trees. I focused on the left of the two nearest trees which was about 3m + way. Possible a little near than needed (hyperfocal distance should be 6.36m) but at F16, the area of softness (shaded red) was nowhere near infinity and appears softer than other areas even further away? 

Picture was shot in RAW & converted to JPG to post here but no other processing carried out.

*Original image* is the untouched image straight from the camera but had to convert to jpg & reduce quality to 8 (High) in Photoshop to reduce filesize in order to post here. If anyone wants to see the original RAW file I can post it on Flickr/Dropbox etc for download.

*Photo 1 full image* shows the whole photo with sections shown in crops highlighted to show positioning.

*Red section 100%* shows a 100% crop that I feel is too soft.

*Blue section 100%* shows a 100% crop of an area at around the same distance that appears sharp(er) to me.

At the end of the day I have little choice in what to do - either sell it or keep it; it's no longer under warranty and Canon say it's fine. I'm tempted to go for the new 24-105 F4l MKII to see what the difference if any is although I know in theory at least that my lens should be superior.

I suppose it does what I want it to do for most of the time, just that for the cost I expected outstanding results at all times. So thoughts greatly appreciated please - does it seem ok/within parameters (as Canon would say) or am I just expecting too much? Or is it my technique?


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## Larsskv (May 11, 2017)

I believe the main problem with your sample image is softness due to diffraction.

I am on my fourth copy of the 24-70 f2.8 LII. The first copy was damaged when my tripod fell over. My first copy and the one I have now is fairly good even in the corners, but are not perfect. My second copy was a little bit worse, and left something to be desired. My third copy was very bad in the upper right part from 24mm to maybe 50mm. 

I got the 16-35 LIII on a rebate a few weeks ago. It far outperforms the 24-70 f2.8LII in corner sharpness at 24, 28 and 35mm, and becomes even better when both lenses are stopped down. It is as sharp as my 35LII when both are stopped down to f5.6.


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## Pookie (May 11, 2017)

Larsskv said:


> I believe the main problem with your sample image is softness due to diffraction.



def... shooting for 25+ years and not aware of this? 

cloudy day at focal length of 55mm @ F16, shutter speed of 2 secs


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## LesC (May 11, 2017)

Thanks guys - was _aware_ of diffraction but didn't expect the effect to be that noticeable 

So what should I have done - F11 & focus further into the scene?

As to the 2 sec shutter speed - is that relevant as camera was tripod mounted??


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## Pookie (May 11, 2017)

LesC said:


> Thanks guys - was _aware_ of diffraction but didn't expect the effect to be that noticeable
> 
> So what should I have done - F11 & focus further into the scene?
> 
> As to the 2 sec shutter speed - is that relevant as camera was tripod mounted??



Your best return by graph is not F11 across the entire field...


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## Sporgon (May 11, 2017)

Irrespective of defraction it looks like a centering issue to me.


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## LesC (May 11, 2017)

Pookie said:


> LesC said:
> 
> 
> > Thanks guys - was _aware_ of diffraction but didn't expect the effect to be that noticeable
> ...



True, but F5.6 or F8 won't necessarily give enough DOF?


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## Deleted member 91053 (May 11, 2017)

I would agree with Sporgon. Mine is sharp all over the image!


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## Mt Spokane Photography (May 11, 2017)

One of the things I like is the edge to edge sharpness. While not perfect at the edges, they are very good, far better than your photo.

Check for decentering, you can print out a star chart, shoot it, and decentering will be obvious.

http://www.bealecorner.org/red/test-patterns/


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## LesC (May 11, 2017)

Mt Spokane Photography said:


> One of the things I like is the edge to edge sharpness. While not perfect at the edges, they are very good, far better than your photo.
> 
> Check for decentering, you can print out a star chart, shoot it, and decentering will be obvious.
> 
> http://www.bealecorner.org/red/test-patterns/



Thanks for this. I only have an A4 printer but presume I just need to focus close enough to fill the frame. Any particular settings ie F stop to use or will decentering be obvious at any aperture if present? I guess I need to use one of the two Star 'Bars' charts?


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## pwp (May 12, 2017)

Thanks OP for bring attention to this. My 24-70 f/2.8II has very good edge to edge sharpness. Like many photographers my primes in this focal range became obsolete overnight and were quickly sold. 

My shooting style tends to use a range from f/2.8-5.6 and rarely beyond. The results are plain stellar. But when I go past f/5.6, the results can disappoint. Shots at f/8 are nowhere near as crisp as f/5.6, f/11 cannot be relied on for commercial quality output and I'd never consider shooting at f/16 as your example image was. 

Is this simply a characteristic of this lens to optimise performance in the wider apertures at the expense of the narrower apertures or should I be taking my lens down to CPS for a health check?

-pw


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## Pookie (May 12, 2017)

LesC said:


> I should add that I've sent sample shots to both my (well respected) camera dealer & to Canon who both felt it was OK and last year *the lens was checked by Canon for sharpness/alignment* when it went in to have filter thread replaced after a knock.* It was passed as OK and indeed I've had some lovely sharp images from it since*.



Does sound like technique and diffraction would be the problem... then again, I've got 3 copies of this lens and none look like this, only take mine out to f/8 and on rare occasions f/11. It's never seen f/16.

Hyperfocal should be around 60ft @ f/5.6, 40ft @ f/8, 30ft @f/11, and 20ft @ f/16.... I bet you could have backed up a bit, chose better and went for hyperfocal for a crispier image.


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## JPAZ (May 12, 2017)

Mine spends most of its time at f /7.1 or faster and I've not noticed this. When I get issues with sharpness, it is usually my fault cause I am using a low shutter speed hand-held. I'd re-do some test shots at a larger aperture and see if that solves the issue. If not, agree it could be a de-centering issue. One final thought, I've gotten some poor results with stellar lenses shot through a lousy UV filter. Did you have anything mounted on the front?


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## LesC (May 12, 2017)

Had both a Hoya Pro 1d skylight filter and a Lee landscape polariser fitted neither of which have given any problems on any lenses before. I'll try some test shots to see what I get under test conditions. 

Am I right in assuming that if decentering is a problem it would be more apparent at smaller apertures, say F8 rather than F16?

Should it be apparent at all focal length too?


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## JPAZ (May 12, 2017)

A couple of things to look at.......

https://www.lensrentals.com/blog/2012/05/testing-for-a-decentered-lens-an-old-technique-gets-a-makeover/

http://blog.kasson.com/the-last-word/simple-decentering-test/


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## LesC (May 12, 2017)

Thanks for that; I'd printed out a star chart but didn't realise that was what I'm supposed to do - I just tokk a series of properly focused shots at various apertures! 

I'll try again tomorrow


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## Mikehit (May 12, 2017)

I find it hard to believe that f16 on a FF camera will give diffraction that bad. The two extracts are about the same distance apart from the camera but the one at the edge is far, far worse. 

This article illustrates effects of diffraction all the way to f32 and IMO this is nowhere near what LesC has seen. 


https://photographylife.com/what-is-diffraction-in-photography/


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## bholliman (May 13, 2017)

Mikehit said:


> I find it hard to believe that f16 on a FF camera will give diffraction that bad. The two extracts are about the same distance apart from the camera but the one at the edge is far, far worse.
> 
> This article illustrates effects of diffraction all the way to f32 and IMO this is nowhere near what LesC has seen.
> 
> ...



Agreed! I've owned a 24-70 f/2.8L II for 4 years and have occasionally shot at f/16. Diffraction softens the results a little (similar to what the TDP lens IQ tool shows below), but nothing like the OP's examples. There is something else going on to cause that level of softness.

http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=787&Camera=979&Sample=0&FLI=2&API=6&LensComp=787&CameraComp=979&SampleComp=0&FLIComp=2&APIComp=3


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## LesC (May 13, 2017)

First thing; many thanks to all who've added to this thread, your contributions are much appreciated & helped greatly.

OK, so I've done the decentering tests at various focal lengths and apertures with camera mounted on substantial tripod, liveview so mirror locked up and as level/perpendicular to chart as possible. As you can see from the images below, it seems decentering is not an issue.

However, I still think something is not quite right - the 3rd image , "Full frame 55mm F8" still appears to show the right hand side of the frame to be less sharp that the other side. An identical image at F16 shows much less difference between the left & right sides of the frame.

These shots were obviously taken at the minimum focus distance of the lens - about a foot away - so I'm assuming the effect is less obvious at greater distances so perhaps why for the majority of times I've not noticed a problem. And of course I'll admit some times 'operator error' may be a factor as more often than not I shoot without a tripod.

I also checked back to see what Canon had said when the lens was checked last year and they only said "lens checked for focus and sharpness" so not sure how much testing was actually done. I had also earlier (when I first had the lens) sent some images to Canon which ironically seemed to show some softness on the left side of the frame which they suggested was lens aberration which could be corrected in DPP.

So I'm left in a bit of a quandary - the lens appears at least at times somewhat less sharp on the right edge, however I have little confidence that Canon would even acknowledge there is an issue or even if they do, there's a risk they'll only make it worse. I may in the first instance email them some shots to see what they say.

In the long term, I may try either the Canon EF24-105L F4 IS MKII or wait for reviews of the soon to be release Sigma Art 24-70 F2.8 which also has IS. I feel a decent copy of either may give better results than my current 24-70. 

Seems to me that Canon's QC leaves something to be desired - I naively expected that by paying for the best I could safely assume the lens would be nigh-on perfect or at least very good. Seemingly not the case


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## Sporgon (May 13, 2017)

I guess you've got some elements out of alignment - "de-centered". Complicated lenses like the 24-70 don't take knocks well, and if you've given it a bang that's probably the cause of the problem, despite what Canon service have said.

I had a 5D that got dropped. Everything was OK except the camera started back focusing, which it hadn't done before. Canon service checked it and said it wasn't out of alignment. I find these problems happen when you have an issue which is great enough to be irritating, but only slight in technical terms.


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## LesC (May 14, 2017)

Sporgon said:


> I guess you've got some elements out of alignment - "de-centered". Complicated lenses like the 24-70 don't take knocks well, and if you've given it a bang that's probably the cause of the problem, despite what Canon service have said.
> 
> I had a 5D that got dropped. Everything was OK except the camera started back focusing, which it hadn't done before. Canon service checked it and said it wasn't out of alignment. I find these problems happen when you have an issue which is great enough to be irritating, but only slight in technical terms.



I think you're right although I was never blown away by the lens' quality even before the knock; before (as indeed after) I've had really nice sharp results with it & occasionally disappointing ones but annoyingly inconsistent enough to pin down the reason. The lens was of course attached to the 6D when it got knocked but I feel the issue is certainly with the lens. I need to use it for a trip in a couple of weeks but after then may contact Canon one more time but I have little faith in their UK repair centre.

Ultimately I think I'll need to get rid & cut my losses. Then I need to decide whether to risk another 24-70 F2.8L MKII, try a 24-105 F4 MKII or perhaps see what reviews are like for the Sigma Art version soon to be released - I rather like the idea of F2.8 and IS...


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## Larsskv (May 14, 2017)

It seems that your lens has some issues, but that is typical for most zoom lenses, and all of the 4 copies of the 24-70 f2.8LIi that I have had, have had some issues - and the copy I have now is much better than my last copy. I recommend this article from Roger Cicala at Lensrentals:

https://www.lensrentals.com/blog/2017/02/things-you-didnt-want-to-know-about-zoom-lenses/

Long story short, zoom lenses are rarely (never) evely good across the frame, at every focal length.


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## LesC (May 14, 2017)

Larsskv said:


> It seems that your lens has some issues, but that is typical for most zoom lenses, and all of the 4 copies of the 24-70 f2.8LIi that I have had, have had some issues - and the copy I have now is much better than my last copy. I recommend this article from Roger Cicala at Lensrentals:
> 
> https://www.lensrentals.com/blog/2017/02/things-you-didnt-want-to-know-about-zoom-lenses/
> 
> Long story short, zoom lenses are rarely (never) evely good across the frame, at every focal length.



Thanks  Interesting article; maybe I'm expecting too much, who knows, but ironically it was also Roger Cicala who in his review of the 24-70 says"The Canon 24-70mm II is the best standard-range zoom ever made. By any manufacturer. Ever. It’s not close" and "If you need the absolute best, then this is what you need"

Trouble is, as you say there can be copy variation and so I find it's difficult to determine if a lens is a poor copy and if so where's the dividing line between poor & actually faulty? Even the comments on this thread suggest diffraction, technique or a fault as possible causes or perhaps as Canon would have it, it is 'within parameters' - I don't even know myself for certain and I guess that's what's frustrating. The fact that performance seems inconsistent doesn't help - I've veered between thinking it's definitely faulty or that it's my faulty technique somehow. BTW, how did you end up with 4 copies?

As most of us buy just the one copy of a lens it's difficult to work out how good or otherwise it is in comparison to others; I optimistically assumed that paying so much for a lens would almost guarantee all copies would be really good 

Think for now I'll hold fire for a while, see how it goes and may look at the sigma when it comes out as I do fancy IS. I'm also looking at getting the 6D MKII when it comes out so might pick up the EF24-105 F4L MKII if it's bundled in as a kit lens with a decent saving.


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## MJB (May 15, 2017)

I have not always been happy with my copy while using on my 5D Mk3, however when I got my 1DX Mk2 the image quality from this lens seemed much better.

My 5D works well with all my other lenses and have never been sure why this particular lens always seemed a bit soft on this camera.

Any suggestions?


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## pwp (May 15, 2017)

MJB said:


> I have not always been happy with my copy while using on my 5D Mk3, however when I got my 1DX Mk2 the image quality from this lens seemed much better.
> 
> My 5D works well with all my other lenses and have never been sure why this particular lens always seemed a bit soft on this camera.
> 
> Any suggestions?



AFMA variations?

-pw


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## LesC (May 15, 2017)

This may be a silly question, but ... how do you know if AFMA may help/be needed? And can AFMA be adjusted for different focal lengths? I admit I've not used it before for fear of making things worse 

When I got my 24-70 I checked focus by focusing on a point on a ruler at F2.8 and as that point appeared sharp assumed focus was ok. Even on my shoot that I experienced problems with (referred to earlier in this thread), I took some shots of bluebells close up at F2.8 that were sharp where I expected them to be.


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## ishootbokeh (May 15, 2017)

I'm on my second copy and I'm still not happy even after having it on for a service. Corners way too soft at 70mm for a lens this expensive. My Sigma 35 art just blows it away for edge to edge sharpness. Pity as I love it as an event lens setup, centre sharpness is great but for large groups I have to be careful with people near the edge of the frame.


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## LesC (May 15, 2017)

ishootbokeh said:


> I'm on my second copy and I'm still not happy even after having it on for a service. Corners way too soft at 70mm for a lens this expensive. My Sigma 35 art just blows it away for edge to edge sharpness. Pity as I love it as an event lens setup, centre sharpness is great but for large groups I have to be careful with people near the edge of the frame.



My thoughts exactly; I don't make my money from my photography but all the same expect more from such an expensive lens. 

Not sure whether to be relieved or disappointed that I'm not the only one


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## ishootbokeh (May 15, 2017)

Not just you for sure. I've tried MFA for hours on end to find the sweet spot but I feel thats not the issue as its excellent in the middle just not great at the corners at 24mm and poor at 70mm.

Out of all my lenses for sharpness on any Canon body my 70-200 IS II just nails it every time, sharp to the corners, worth every penny. No MFA needed either, great to be 100% confident when it matters, joy to use.

Maybe a 5dmk4/6dmk2 and a possible 24-70 2.8 IS II would be the dream AF/sharpness combo!


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## LesC (May 15, 2017)

Interesting to see what the Sigma Art 24-70 F2.8 with IS is like - due out soon I believe...


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## ishootbokeh (May 15, 2017)

LesC said:


> Interesting to see what the Sigma Art 24-70 F2.8 with IS is like - due out soon I believe...



Going to be very interesting indeed. I've been very impressed with Sigma art series lenses after a little MFA, great performance and good on your pocket too!


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## Larsskv (May 15, 2017)

LesC said:


> Larsskv said:
> 
> 
> > It seems that your lens has some issues, but that is typical for most zoom lenses, and all of the 4 copies of the 24-70 f2.8LIi that I have had, have had some issues - and the copy I have now is much better than my last copy. I recommend this article from Roger Cicala at Lensrentals:
> ...



Copy nr 1 damaged when my tripod tipped over.
Copy nr 2 sold to finance my 35LII + I also had the quite excellent 24-70 f4 L IS
Copy nr 3 was bought used and was really bad in the upper right corner. Sold it to buy the 50L.
Copy nr 4 bought new at a really good (Norwegian) price on sale. This was the first of my copies that could compete with the 24-70 f4 L IS in terms of corner sharpness. Sold the f4, and is a happy owner of this fourth copy. Still corners are never perfect with this last copy, especially on my 5Ds. My 16-35 f2.8 LIII is much better on comparable focal lengths and apertures.

I think all my copies of the 24-70 f2.8 LII in general have been really good at f2.8 and for photos with a blurry background, but it has been hard to find a copy that performs well for landscapes (because of lack of corner sharpness).


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## LesC (May 15, 2017)

Thanks; interesting - so you rate the EF24-70 F4L highly then?


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## Larsskv (May 15, 2017)

LesC said:


> Thanks; interesting - so you rate the EF24-70 F4L highly then?



The 24-70 f4 L IS is really good, and as good as a good copy of the f2.8 L II for landscapes, and is quite light and small. The 24-70 f2.8L II is a tiny bit sharper in center, has a little more contrast and clarity, and has nicer bokeh. I think the f2.8LII is the better all purpose zoom, but the f4 L IS provides very good value for money.


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## MJB (May 16, 2017)

I have tried AFMA and could still not get the results I was hoping for, reluctant to send it to Canon as it works well with the 1DX Mk2.


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## R1-7D (May 16, 2017)

I don't think you'll be able to properly tell if this is a decentering issue unless you shoot something that's all on the same focal plane, such as a brick wall.

Just looking at your original image, all the blue flowers in the foreground are sharp across the image, and they appear to be pretty much on the same plane. It is hard to tell with the trees in the background.


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## LesC (May 16, 2017)

R1-7D said:


> I don't think you'll be able to properly tell if this is a decentering issue unless you shoot something that's all on the same focal plane, such as a brick wall.
> 
> Just looking at your original image, all the blue flowers in the foreground are sharp across the image, and they appear to be pretty much on the same plane. It is hard to tell with the trees in the background.



Appreciate what you're saying but the two star chart shots (in focus & defocused) seem to suggest it's not decentering. However the 3rd image of the star chart shot at F8, if you view full size appears to be less sharp on the right side, to my eyes at least??


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## R1-7D (May 16, 2017)

LesC said:


> R1-7D said:
> 
> 
> > I don't think you'll be able to properly tell if this is a decentering issue unless you shoot something that's all on the same focal plane, such as a brick wall.
> ...



The left side of the third chart appears marginally sharper. There's some color or temperature differences, however, as well as differences in contrast between the left and right side of the image. This can play with the viewer's perception of sharpness. 

Have you run the lens through Reikan FoCal's Aperture Sharpness test? Perhaps your lens's sharpness falls off drastically at f/8. I know on my copy it's sharpest at f/3.2 and stays even until f/6.3, and then starts going down. If you're seeing this phenomenon at f/8, there's a chance that you're just noticing a very slight decentering of the element more so at that narrower aperture than at wider apertures.


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## LesC (May 16, 2017)

[/quote]

The left side of the third chart appears marginally sharper. There's some color or temperature differences, however, as well as differences in contrast between the left and right side of the image. This can play with the viewer's perception of sharpness. 

[/quote]

Good point; colour/temperature difference were I think due to my printer's dodgy B&W printing & the lack of contrast on the right side may be due to light from a window on the right...

Haven't got Reikan FoCal but now might be a good time to invest in it  I was looking in to it but seems it may have some issues with the EOS 6D ? See here: http://www.reikan.co.uk/focalweb/index.php/2013/02/focal-and-canon-6d-support-update/


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