wickerprints wrote:
I'm just gonna put this out there as a whimsical prediction, so that when various results do come in, I might be able to refer back to this post to see how accurate my predictions were.
First, I'm going to predict that the visible differences between the 1.4x II and 1.4x III are going to be very, small. On the 300/2.8L IS (I), the center will be very nearly unchanged in sharpness. The periphery will likely see a small improvement in lateral CA, but not eliminated.
Overall, Mark I telephoto primes won't see much improvement with the 1.4x III compared to the II; the most noticeable differences will be slightly better corner performance.
The 2x III, however, will be more noticeably improved over the 2x II. Corner performance in particular will be significantly better, with less CA and better resolving power. However, center performance again will be only marginally better. Overall, the improvements will be modest, but easily observable at 100% crop....Show more →
What are your predictions in terms of AF performance??
I found a Canon website which raises doubt IMHO that the Mk III extenders will be much of an improvement especially in terms of AF performance, when used with earlier model EF lens (that is non-Mk II super telephotos). And I had almost placed my orders for one of each.
Extenders EF 1.4X III and EF 2X III have been newly developed in conjunction with the new Series II Image Stabilizer EF super-telephoto lenses. They can also be used with all previously announced extender-compatible EF lenses, but maximum performance is achieved when they are used with the new 300mm, 400mm, 500mm and 600mm lenses. The following sections provide more detailed information.
Image Quality
There are two significant improvements related to image quality when using the new Series III Extenders with the new IS II super-telephoto lenses:
Anomalous dispersion glass elements are used in both new extenders to effectively reduce chromatic aberration to the greatest possible extent. This results in higher resolution and contrast, especially when the new extenders are used with IS II super-telephoto lenses.
Each Series III Extender features a newly developed microcomputer that increases AF precision when the extenders are used with an IS II super-telephoto lens. AF precision remains the same as the Series II Extenders when the Series III Extenders are used with earlier extender-compatible EF lenses.
As a result of these improvements, users of the new IS II super-telephoto lenses can expect significantly improved image quality when using Series III Extenders.
genefixer wrote:
I found a Canon website which raises doubt IMHO that the Mk III extenders will be much of an improvement especially in terms of AF performance, when used with earlier model EF lens (that is non-Mk II super telephotos). And I had almost placed my orders for one of each.
Extenders EF 1.4X III and EF 2X III have been newly developed in conjunction with the new Series II Image Stabilizer EF super-telephoto lenses. They can also be used with all previously announced extender-compatible EF lenses, but maximum performance is achieved when they are used with the new 300mm, 400mm, 500mm and 600mm lenses. The following sections provide more detailed information.
Image Quality
There are two significant improvements related to image quality when using the new Series III Extenders with the new IS II super-telephoto lenses:
Anomalous dispersion glass elements are used in both new extenders to effectively reduce chromatic aberration to the greatest possible extent. This results in higher resolution and contrast, especially when the new extenders are used with IS II super-telephoto lenses.
Each Series III Extender features a newly developed microcomputer that increases AF precision when the extenders are used with an IS II super-telephoto lens. AF precision remains the same as the Series II Extenders when the Series III Extenders are used with earlier extender-compatible EF lenses.
As a result of these improvements, users of the new IS II super-telephoto lenses can expect significantly improved image quality when using Series III Extenders....Show more →
Yep, that seems to be the long and the short of it. I shot some pics of the eclipse with the version II 2x extender on my 500 mm lens and noticed some significant CA that the 500 normally doesn't have. I'm sure the newer one will reduce that, but I'm also sure the new extenders aren't the panacea some are looking for.
PetKal wrote:
Not easy for an engineer to ignore the trivial construction detail, eh ?
However, I think we'd primarily like to hear an assessment of the IQ impact the new TC makes. The proof of the pudding is in the eating.
Whatever it takes too keep this thread on top, and to camouflage my impatience
Since we have such generous people on this board that are willing to put time into testing and presenting the results, we cant scare them away with our inner thoughts: "Come on, where are the results? I have refreshed my browser 100 times the last hour, but nothing happens!"
nsarcastic wrote:
Yep, that seems to be the long and the short of it. I shot some pics of the eclipse with the version II 2x extender on my 500 mm lens and noticed some significant CA that the 500 normally doesn't have. I'm sure the newer one will reduce that, but I'm also sure the new extenders aren't the panacea some are looking for.
I've noticed a little of that on the 400/2.8 with the 2X also, and it isn't visible with the naked lens, or the lens with the 1.4X.
I think that the 2X will show the most significant improvement. The 1.4X Mk II is really good already, IMHO.
Here a little test executed today. I am not too much into testing and this is not scientific.
You will find a shot done with the old extender and one done with th enew extender placed on a 70-200 f/2.8L IS II, on tripod, stabilizer off, f/4, focus done on the middle straw that passes over the nose; focus was mode the this specific point. No sharpening was applied. Shot with a 1D MK IV.
I omade observations that the new one was not faster. I did not see differences in chromatic aberration.
And yes, the new one has 7 xcrews instead of 4 for the old one on the camera mount siside (that's for the engineers and I personnaly do not care at all...)
Asking permission before, shows a sign of respect for people. I do not denie the usefulness of the action, just the way it was done in this era of "I don't care"
The difference is pretty obvious to me. I have seen other examples that show that the III is sharper well.
I have the 2x II and 2x III shipping from B&H right now. When they arrive, I won't even open the II. It's going right back based on what I have seen the last few days on this forum and POTN.
Well you have the righ to your opinion but you do not have the right to play with my shots.
JD
Thank you for conducting your preliminary tests. It is most appreciated. That said, I'm sure Imagemaster meant no offense to put your images side-by-side; I personally found it to be very helpful to see the differences. Notice, for example, how you can see the fabric texture in the III version, but the same texture is much softer in the II version. That is very encouraging for the center sharpness.
As for the screws, I'm also glad that you have confirmed that there are more screws. This may appear to be insignificant or cosmetic, and for a smaller lens it may not matter, but for heavier lenses, it is a very encouraging sign. There have been reports of the old extenders becoming loose over time and requiring servicing to straighten them up again. So you can take comfort in the added reinforcement of your new Extender III.
Future tests I hope to see (not necessarily from you specifically) include a comparison of corner performance, which might be done by manually focusing in Live View. That would give us added valuable information about how the extenders affect image quality across the frame. But the results you have posted here are very positive, very positive indeed.
Totally agree with Imagemaster. I think if you were shooting a lens with a fingerprint on the front element, removing the fingerprint would provide about the same difference as going from an EXII to III. Or maybe changing filters from a Hoya to a B&W MRC would provide a similar improvement. Clearly not worth my investment but to each his own. Canon isn't blowing their horn either on what they will do for older lenses including the 70-200 2.8 II and they certainly would if there was a significant change.
Did you use tripod for testing? If not - the difference may result from camera movement. Lets hope tho there is such improvement in sharpness cause otherwise it would make no sense to go for the new version, paying significantly more for nothing (unless you plan to buy the lenses that are not available yet and cannot be tested to justify the purchase of TC III).
geniousc wrote:
Totally agree with Imagemaster. I think if you were shooting a lens with a fingerprint on the front element, removing the fingerprint would provide about the same difference as going from an EXII to III. Or maybe changing filters from a Hoya to a B&W MRC would provide a similar improvement.
Do you have some evidence to back your claim? Or are you going to just say things you think are true and present them as fact?
Clearly not worth my investment but to each his own. Canon isn't blowing their horn either on what they will do for older lenses including the 70-200 2.8 II and they certainly would if there was a significant change.
The fact that the center performance could even be improved at all is a very encouraging sign--it was already pretty damn good for the 1.4x II. If you want to save your $200 and stick with the old version on the basis of a single test of the center performance without ever having seen a comparison in the periphery, then you're more than welcome to. The rest of us are going to be patient and look for more reports to trickle in, rather than jump to conclusions.
John Daniel wrote:
You will find a shot done with the old extender and one done with the new extender placed on a 70-200 f/2.8L IS II, on tripod, stabilizer off, f/4, focus done on the middle straw that passes over the nose
jcbenner wrote:
So 7 screws on the mount between the TC and camera, but 4 screws on the mount between the TC and lens...
I guess most people connecting tc to the lens first and both to the body after. At this point damage might happen. I broke 1.4 mk II pin with 500L and I like new extender build better. Also happened that tc to body mount rotates bit since just 4 screws there.
wickerprints wrote:
Does that answer your question?
Must have been blind xD Thanks for the info.
Canon has great pricing advisers, as they're gonna squeeze a lot of cash from us for every tiny improvement. I'm happy I havent bought any TC yet, but now it will be a tough decision - TC MK II or III or maybe Kenko...
