I have read the reviews, know the price difference, but have not used either lens.

Yes, I want sharp and the ability to use the 1.4x or 2x.

Has anyone had experience with either lens or both?

I haven't used either, outside of a tradeshow booth, but I used to own the 200/2.8L II and a 2x Extender. With that combo, autofocus became very slow and the images were noticeably softer than with the naked lens. If you go with the f/4 lens, then I don't believe that AF will even work with the 2x Extender and you'll need a lot of light for the f/8 combo. I'd definitely not go past 1.4x times with the f/4 lens. Even with the f/2.8 lens, the 2x Extender might soften things more than you like.

I used the Mk II extender. Maybe the new, Mk III is sharper and supports improved AF.

Interesting I have heard by two photographers I know that the new 300 2.8 and 2xIII work like a dream.

Agree the f4 would not be worth extending.

Interesting I have heard by two photographers I know that the new 300 2.8 and 2xIII work like a dream...

That may very well be. I owned the 200L II and 2x II before the III was released. The 300/2.8 starts out sharper than the 200, and Canon says they improved the Mk III extender sharpness and quickness.

Still, if I had to do it again, I would have bought the 1.4x extender, rather than the 2x - at least for the 200L and the Mk II generation of extenders.

But it really depends... If you are shooting sports photos, you want quick AF and can crop, so 1.4x might be the right choice. If you're shooting video, AF doesn't matter and cropping isn't an option for an HD output, so 2x is fine if f/5.6 isn't too slow. Also, the sharpness isn't as critical for video as it is for photos. I wanted both. ;)

I think the extender is a second thought and one I would not even consider until I choose the lens. 1.4x could be fine. It would be used 90% for stills on the MKIII in demanding conditions. And it would be used on the C300 in rare locked down shots.

I need to find out how much better the f4 is then the older f2.8 and newer f2.8.

Most Canon still shooters I know in my industry say the 2.8 is the sharpest lens Canon has made for DSLR. So how much better is the new on then the old 2.8. Big price difference.

Here are the head to head comparisons (mouse over to see the 2nd lens). First resolution...

Canon EF 300mm f/4.0 L IS USM Lens Image Quality (http://thedigitalpicture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=111&Camera=453&Sample=0&FLI=0&API=0&LensComp=249&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=2)

Canon EF 300mm f/2.8 L IS USM Lens Image Quality (http://thedigitalpicture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=249&Camera=453&Sample=0&FLI=0&API=0&LensComp=739&CameraComp=0&FLIComp=0&APIComp=0)

Canon EF 300mm f/2.8 L IS II USM Lens Image Quality (http://thedigitalpicture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=739&Camera=453&Sample=0&FLI=0&API=2&LensComp=111&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=0)

And then vignetting...

Canon EF 300mm f/4.0 L IS USM Lens Vignetting Test Results (http://thedigitalpicture.com/Reviews/Lens-Vignetting-Test-Results.aspx?Lens=111&FLI=0&API=0&LensComp=249&FLIComp=0&APIComp=1&Camera=9&CameraComp=9)

Canon EF 300mm f/2.8 L IS USM Lens Vignetting Test Results (http://thedigitalpicture.com/Reviews/Lens-Vignetting-Test-Results.aspx?Lens=249&FLI=0&API=0&LensComp=739&FLIComp=0&APIComp=0&Camera=9&CameraComp=453)

Canon EF 300mm f/2.8 L IS II USM Lens Vignetting Test Results (http://thedigitalpicture.com/Reviews/Lens-Vignetting-Test-Results.aspx?FLI=0&API=1&FLIComp=0&APIComp=0&Lens=739&Camera=453&LensComp=111)

As I see it, they're all killer lenses. Me? I might go for the older f/2.8.

The f/4 performs well, but the other two are better at f/4. No surprise. I like speed, so I'm drawn to the faster glass.

The f/2.8 lenses both rock, but the II is freaking amazing in the mid an corner areas. Geez! That said, I wouldn't be buying that lens for f/2.8 shots of landscapes and images of detailed walls. I'd be shooting sports, wildlife, and/or people with a large aperture. And for those shots I want the subject sharp and the corners will be a DOF blur. And who needs sharp corners for that? If I'm shooting for corner to corner detail across a canyon, I'm stopping down to f/8 and any of the lenses will sing at that setting.

According to the review...
Canon EF 300mm f/2.8 L IS II USM Lens Review (http://thedigitalpicture.com/Reviews/Canon-EF-300mm-f-2.8-L-IS-II-USM-Lens-Review.aspx)
...the newer lens gives better IS, but the older lens does as well if not better for AF.

And, yes, the newer lens with the 2x Extender III looks to be magnificent. I might stick with 1.4x for the older lens, but 2x looks to be amazing with the new glass.

As for minimum focus distance, the f/4 lens wins hands down, so it might be the best closeup lens. The older f/2.8 is pretty weak for minimum focus distance.

All of the choices look to be excellent. The new f/2.8 is other-worldly. But do the sharp corners, better IS, and shorter MFD matter? It all depends on what you shoot.

Fortunately, there is no bad decision here - especially since top glass is more stable than government bonds. :)

Thanks Jon for taking the time to put together the info. I am done for the day and on the road tomorrow. Will check it out in more detail tomorrow evening.

OK I am still waiting on a render.

I agree with your comments most of the time the edges will be blurred. And speed is great when i shoot at dusk or sunrise. So now to try them first hand.

I think the f2.8 version could be found for 1/2 the price of f2.8 II.

Paul (OP):

I am not sure the reason you are buying a 300mm lens. Let me share a few comments & they do not apply, so be it.

1. I have a 400mm F5.6 lens I use mainly to shoot surf photography. I considered buying the more expensive 400mm lens (bigger aperture) or the 500mm lens. When I checked the actual clarity of each lens, my lens performed well & cost a fraction of the others. After owning & comparing my lens to the ones I lusted for, I realized I was happy I ended up not laying out over 6 grand for soomething that does only slightly better at what I use it for.

2. I shot my 400mm for an hour, then the next hour with my friends 500mm F4 shot the same surf spot. At times I used my 1.4 extender. The bottom line is the more I shot with his expensive 500mm lens, the more I realized the cost & weight (hassle when traveling) was not as wonderful as I thought it would be. Cropping with my 400mm lens did not reduce the quality of the photo significantly enough to merit paying 5X as much for the lens 500mm lens IMO. If he traded me straight across, of course I would take his but not sure it is worth even $1500 more to me vs the $4500 more it cost then my 400mm.

3. When using a 1.4 extender, the auto-focus is too slow IMO. To be blunt, when shooting far away like I do, I found auto-focus ruins as many photos as it helps simply because the light reflecting off the water trips up the auto-focus by focusing on a reflection out of focal range of my subject. When manually focusing, I can keep the focus correct from where the surfers take off & end their ride/kick out. Basically shooting in manual focus is not a big negative for me.

4. I have used my 2X extender & of course the reduction in quality is noticeable. The 1.4X is fine, 2X is a reduction I do not prefer to use. What I found out is when you get to the point of needing 800mm lens, the 500mm comes up a bit short as well & now you are dealing with something like a $8000-$10,000 lens (have not checked the prices lately). For me, at this point, better to take my 70-200mm lens, throw my 1.4 extender if needed & shot from a boat, get a better angle vs using a lens that needs to be 800mm or crop it so much. Yes, I might have to pay $20 a day to shoot from a boat but better to pay $20 than a massive amount for a 800mm lens etc.

5. My friend that let me use his 500mm lens is a professional photographer & shoots 1300 photos a day at this surf spot & then sells them to wanting surfers. I am certain the difference in a 400mm cropped photo vs a 500mm photo would not make a difference in who bought a photo & besides those that simply love to debate about lens would care about the difference between the two.

6. I think there is a bigger difference between the Canon 100-400mm lens vs my prime 400mm lens than the 400mm f5.6 I own vs the 500mm prime f4 I shot with. You will find the 100-400mm lens is very soft around the edges compared to a prime.

7. Regarding surf photography, the F4 vs f5.6 is more about light then clarity IMO. Even when it is overcast in Calif & 6am., I can shoot at over 1/1000 of a second & moe often shooting at over 1//2000 which is more then fast enough. The worse I have to do in low light situations is push my ISO up to 400. I really cannot justify paying so much more for 1 f stop.

All of this makes me feel that unless you are shooting for national geography, are obsessed with having the largest aperture for bragging rights, or simply money is no issue, the more expensive 400mm/500mm lens are not needed.

I enlarge photos 20x30 all the time, they look great. My main point is everything in life is a compromise be it size & quality of lens, size of aperture, & cost of equipment vs need for quality. Everyone varies in needs & desires. For me, you can see I compromised with a 400mm prime @ f5.6 vs a 500mm prime F4. The bottom line is if you are happy with what compromise you made, then you made the right choice. I have found the person shooting the photos & their ability to capture the surfer at the right time etc is much more important than the f5.6 400mm vs f4 500mm issue.

Again, I do not know your needs so some or all of this maybe worthless information.

Jeff,

Thanks you for taking the time to response, that is the first hand input I am after.

My shooting is on the water boat to boat and in the helicopter shooting boats, just like most of my video. And even at times shooting surfing from the shore. A lot of time I can get away with the 70-200 but most of the time I feel the 300 would be perfect when the boats are big or when there is a fleet and you can't get close enough.

Your points about f2.8 vs f4 for me are spot on what I am dealing with on the water. I bet know one would know the difference if I shot with f4 or f2.8 since there is alway light and reflection only adds to the light. Also the 5D MKIII has a great useable ISO range.

Makes sense with the AF not working well with 1.4x. I live by manual focus with my video and have no problem doing that for long stills. Are you using the II or III in the 1.4x extender?

Off to make the donuts for the day. Thanks again Jeff your post has been very helpful.

OK back from Rule Camera in Boston checking out my rig choice for the C300 and buying a few items.

Then I went to Andrew at the rental desk who has helped me out for years and knows his stuff, as they all do at Rule. His suggestion is buy the new 70-200 f/2.8L II and the 2x III extender. He said the combo is great and they do not rent the 300 due to cost of lens and how few times they will rent it.

Well I am going to buy the 70-200 anyway so I will see if I can rent the 1.4x III and 2x III to check them out.
Be nice to try the 300 f/4 at the same time if possible. Andrew did give me a rental house local that has all of them, so maybe a long weekend with nice foliage and both cameras.

It will be a week or so but will post what I find out.

I have the Canon 300mm F4 IS lens and it is very sharp. I was surprised how nice the lens was considering it only costs about $1400. The IS works very well when shooting in low light. I have also used it on my 5DM3 when shooting video and it is wonderful for interviews when you really want the background to drop off.

Daniel appreciate the input.

You say the lens is sharp when shooting video. Do you use it for stills often? Next week I get a chance to use a buddies 300 f/4 so I should answer my own question but always nice to have owners input.

Here is an image I took with the 300mm f/4L IS lens plus the 1.4x extender. The exif data shows a stop of 7.1 but considering the extender adds a stop the lens itself is only stopped down to about f/5.

Thanks Chris,

Which 1.4x extender is it the I, II, or III?

It was v2.

Great thank for the quick response.

Someone mentioned poor AF with the Canon 2X. I am afraid I don't own any of the 5D options, but I wonder if the latest 5D3 would be better for AF with a 2X. I am basing this on my 1D bodies (1DsMK3 and 1DMK4) both of which have surprisingly good AF performanace with a Canon 1x and cheap after-market 2X converters mounted together with a 70-200mm f2.8 - and this was looking at the moon, so hardly a bright and contrasty scene.

I beleive the 5D3 has an excellent AF system, so I suspect would be as good as my 1D bodies in this respect.

I find AF pretty good with the Canon 2X converter. I even use it on the Sigma 120-300mm f/2.8 OS (latest image stabiliser version) and it works great for stills (although I use manual most of the time for video).

The Canon 300mm f/2.8 is a superb lens and slightly sharper than the f/4 IS L version, although I do like the lightweight and compactness of the smaller lens, plus close-focus semi- 'macro' of the f/4. The f/4 IS L is a bit slower than the 2.8 L version in auto-focus, and also much slower than the Sigma f/2.8.

I actually much prefer the Nikon Nikkor f/2.8 ED-IFN compared to the Canon 300mm f/2.8 L version, but in reality all provide sharp photos...and video is so much lower resolution than stills, that you would never spot the difference. So it all boils down to handling and light-gathering power.

Yeah, the 5D2 AF is a 2nd class citizen compared to the 1D line and the 5D3. Adding the 2x Extender II slowed things down to a crawl on the 5D2. The Mk III extenders are faster, and the 5D3 is much faster, so even though the extender will still slow things down, the overall speed is likely still very good.

I'd imagine that it depends on what you shoot. If it's smooth and at a distance, no problem. If it's unpredictable and close, every millisecond counts.

But yeah, on the 5D2 with the 2x II, AF became frustratingly slow at times.

Daniel appreciate the input.

You say the lens is sharp when shooting video. Do you use it for stills often? Next week I get a chance to use a buddies 300 f/4 so I should answer my own question but always nice to have owners input.

Paul,

Yes I find that the lens is sharp. It is much sharper than the Canon 70-200 2.8 L (version 1) that I also use.

It is also easy to hand hold in low light. Paired with my Canon 5DM3 it makes a great pair when shooting low light event coverage.

Jeff,

Thanks you for taking the time to response, that is the first hand input I am after.

My shooting is on the water boat to boat and in the helicopter shooting boats, just like most of my video. And even at times shooting surfing from the shore. A lot of time I can get away with the 70-200 but most of the time I feel the 300 would be perfect when the boats are big or when there is a fleet and you can't get close enough.

Your points about f2.8 vs f4 for me are spot on what I am dealing with on the water. I bet know one would know the difference if I shot with f4 or f2.8 since there is alway light and reflection only adds to the light. Also the 5D MKIII has a great useable ISO range.

Makes sense with the AF not working well with 1.4x. I live by manual focus with my video and have no problem doing that for long stills. Are you using the II or III in the 1.4x extender?

Off to make the donuts for the day. Thanks again Jeff your post has been very helpful.

Paul:

I have a 1.4x EF Extender II. Has anyone seen a significant improvement with the III?

I had a chance to try the f/4 300 on the MKIII and thought it was great for stills. Did not try it on the C300 since my Movcam rig with rails comes this week.

As many have pointed out the MKIII is a huge step up in that ability to grab the quick focus over the MKII. Thanks Canon this is a huge help with the f/4 300 and I bet with extenders.

As for the extenders I have not had a chance to test any of them. If I was to just buy one it would be the 1.4x III. This is a extra 120mm and if I need longer then that I need longer glass. Also it should work well on the 70-200 which will fill a nice gap between the 200 and the 300. Sounds like I have made my decision.

I appreciate all the great input and advice from all of you. Thanks!

I have a 1.4x EF Extender II. Has anyone seen a significant improvement with the III?

Jeff, I have that exact version as well. By the way, I found the Canon EF 2x II extender way too soft (even for video) as I've mentioned elsewhere on DVinfo.

Here is a very good review that often compares the III and II versions of the Canon EF 1.4x Extenders. It's on a well respected camera site (albeit one primarily aimed at photographers rather than us video folks):

Canon EF 1.4x III Extender Review (http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-1.4x-III-Review.aspx)

Hope this helps.

Thanks Andy that was a good read. I will go for the 1.4xIII.

Jeff, I have that exact version as well. By the way, I found the Canon EF 2x II extender way too soft (even for video) as I've mentioned elsewhere on DVinfo.

Here is a very good review that often compares the III and II versions of the Canon EF 1.4x Extenders. It's on a well respected camera site (albeit one primarily aimed at photographers rather than us video folks):

Canon EF 1.4x III Extender Review (http://www.the-digital-picture.com/Reviews/Canon-Extender-EF-1.4x-III-Review.aspx)

Hope this helps.

Thank you for the link. I thought this was interesting "At review time, the price differential between the still-available version II extenders and the version IIIs is rather high. If the prices were equal, there would be no question that the III is the extender version to get. But, saving money is one of the reasons to buy an extender instead of a lens with a longer native focal length. And I'm sure that not everyone can justify the cost difference to go with the 1.4x III over the 1.4x II".

Jeff I think for the $100 difference it is worth every penny.

Just received the EF 70-200 2.8L IS II. Wow, I forgot how nice this lens is to use and fantastic stabilization.

Next week the 300 and 1.4x which should work very well on the 70-200.

Nice to finally have a glass selection to start using the MKIII on some still jobs.

Just an update to this thread for the people who spent the time to help me.

I have purchased the 1.4x III extender and EF 300 mm f/4L. Both will show up in the next two days.

The 5D MKIII has been a fantastic for stills with my current glass: EF 14 f/2.8L, EF 24-105 f/4L IS, EF 70-200 f/2.8L II. Next on the list is the EF 8-15, and 17mm tilt and shift. Sure more will be needed but that will get me through the next few jobs.

Thank you all for the help.

Gear arrived today and first test with the EF 300 f/4 IS and Extender 1.4x III on my 5D MKIII shows great promise. The zoom is very fast and the lens seems to be nice and sharp.

I did notice you do not want the lens switch on 1.5M distances with the extender, seems to get confused. With the switch on 2.5 is works great. This makes perfect sense to me. Also extender on the lens prior to lens on the camera is important.

Of course the lens with out the extender works fantastic and you save a stop. Surprised how small this lens is not much bigger then my 70-200 and feels lighter.

I think the MKIII focus is a very big help as we discussed.