[Gazzajagman]

The main benefits of the mkIII over the mkII is that the mkIII has newer coatings and is less dust and finger print prone...whihc easily happens when juggling lens caps and teleconverters. It's also built a bit better too. IQ wise, there's a small marginal improvement over the MKII but nothing dramatic. Contrast is said to be a bit better with the mkIII too.
The mkII TC's stack together, I've been told that the mkIII's do not (although I can't confirm this).
I'm still using the mkII converters and I'm quite happy with them.

[Roy C]

Originally Posted by Gazzajagman

The main benefits of the mkIII over the mkII is that the mkIII has newer coatings and is less dust and finger print prone...whihc easily happens when juggling lens caps and teleconverters. It's also built a bit better too. IQ wise, there's a small marginal improvement over the MKII but nothing dramatic. Contrast is said to be a bit better with the mkIII too.
The mkII TC's stack together, I've been told that the mkIII's do not (although I can't confirm this).
I'm still using the mkII converters and I'm quite happy with them.

To get the best out of the new converters you do need one of the new superteles for which they were developed from everything I read, Although they do work OK with existing lenses the IQ gain is marginal like you say.

Every report I have read by users of the new 300/2.8(and 400/2.8) + MkIII 2x tc say that the combo is a significant improvement but not so with the 1.4x tc.
I would not upgrade to a new 2x tc if using an existing lens but most certainly would do so with one of the new lenses.

You are right about the new tc's not stacking but this can be overcome by using a small extension tube between the two or by using a non Canon 1.4x like the Kenko pro (not heard if this would work OK with the new lenses though although I see no reason why it would not).

[GYRob]

Originally Posted by Lisa W

Rob, valid points. I currently have the 400 DO and feel it is a little soft and the contrast is not the best for birding - even when bumped up in camera and post processing. I have some lenses hanging around that I haven't been using, so if I could sell them and cover the majority of the cost I can see moving up to the faster lens. If I can't I'll just hang on.

if weight is not a problem sell the DO and get a 300f2.8 isL Not nessasarly the new one your Do should just about get enough cash, then a couple of the older tc.s
I doult it would cost you much extra .
Rob.

[shanagan99]

I have the 200 2.8 IS with the 1.4 fitted and its brilliant I use handheld mostly but have a lightweight monopod fitted all the time which i use as necessary for macro and birding when its a matter of waiting a while... my thoughts of the 2x is to fit when sitting in a hide for the longer shots where i can rest the weight on the hide opening ... I have been told its just as good to use what i have and crop more. But if the 2x still gives good shots with my lens i would get one soon as ? what do you think knowing how it would be used ?

[johnf3f]

Originally Posted by Lisa W

Rob, valid points. I currently have the 400 DO and feel it is a little soft and the contrast is not the best for birding - even when bumped up in camera and post processing. I have some lenses hanging around that I haven't been using, so if I could sell them and cover the majority of the cost I can see moving up to the faster lens. If I can't I'll just hang on.

Surprised at you describing the 400 DO as a little soft. I have tried 2 used examples and they were the sharpest long telephotos I have tried. True the 400 DO loses out in colour and contrast ( I believe this is due to the DO optics) but they were both sharper than my 600 F4 IS when the image was cropped to equivalent field of view.
I was VERY surprised as this was the opposite of what I was expecting, having read the reviews. I prefer the IQ on the 600 F4 IS but the 2 400 DO's I tried were sharper and had better resolution on both my 1D4 and friends 1D3!
This left me very confused and wanting one! However the low cantrast and muted colour would put me off using extenders much, I just want the light weight!

[Hor Kee]

Originally Posted by johnf3f

Surprised at you describing the 400 DO as a little soft. I have tried 2 used examples and they were the sharpest long telephotos I have tried. True the 400 DO loses out in colour and contrast ( I believe this is due to the DO optics) but they were both sharper than my 600 F4 IS when the image was cropped to equivalent field of view.
I was VERY surprised as this was the opposite of what I was expecting, having read the reviews. I prefer the IQ on the 600 F4 IS but the 2 400 DO's I tried were sharper and had better resolution on both my 1D4 and friends 1D3!
This left me very confused and wanting one! However the low cantrast and muted colour would put me off using extenders much, I just want the light weight!

From my dad's experience, the DO can have serious front or back focus issues, likely due to the DO element itself. My dad eventually sold his to an owner of a 7D with focus micro-adjust. Even when adjusted with -15, it was still not sufficient to correct the focus anomaly. Perhaps sending the lens back to Canon for calibration will help.

[shanagan99]

great posts lads but doesnt answer my question

[Roy C]

Originally Posted by shanagan99

I have the 200 2.8 IS with the 1.4 fitted and its brilliant I use handheld mostly but have a lightweight monopod fitted all the time which i use as necessary for macro and birding when its a matter of waiting a while... my thoughts of the 2x is to fit when sitting in a hide for the longer shots where i can rest the weight on the hide opening ... I have been told its just as good to use what i have and crop more. But if the 2x still gives good shots with my lens i would get one soon as ? what do you think knowing how it would be used ?

You will capture more detail with a converter than cropping heavier - you may be able to crop and get a sharpish shot but you will never be able to put detail into a shot that was not there to begin with! so NO, cropping is not a substitute for more focal length.

[GYRob]

Originally Posted by shanagan99

so i have the canon 300 2.8 IS with a 1.4 converter would you reccomend using a 2x with this lens or would there be little to gain ? I take bird and wildlife shots !

yes it works best on this lens.
Rob.

[Roy C]

Originally Posted by shanagan99

great posts lads but doesnt answer my question

Hi, I answered your query about if it was worth getting a2x tc for the 300/2.8 back in post #17.
I have also answered your question about cropping v tc (I am guessing you meant 300/2.8 and not 200mm).

Just to re-cap:

a) Yes it is certainly worth getting a 2x tc for the 300/2.8

b) Extra focal length (by way of a converter) will always capture more detail than cropping - no amount of cropping will get detail that was not captured to begin with!

Just as a sampler of the 300/2.8 ability to take converters here are a few shots taken with Stacked tc's (1.4x + 2x) giving 840mm - all taken with the 7D. Not for everyday use but handy when you are reach limited. Note just using the 2x tc is obviously a lot better

[Lisa W]

Surprised at you describing the 400 DO as a little soft. I have tried 2 used examples and they were the sharpest long telephotos I have tried. True the 400 DO loses out in colour and contrast ( I believe this is due to the DO optics) but they were both sharper than my 600 F4 IS when the image was cropped to equivalent field of view.
I was VERY surprised as this was the opposite of what I was expecting, having read the reviews. I prefer the IQ on the 600 F4 IS but the 2 400 DO's I tried were sharper and had better resolution on both my 1D4 and friends 1D3!

John, maybe I ought to have another go at microfocusing, I have a problem doing that as my eyesight is pretty bad (not correctable to 20-20 with glasses). Actually I'll be visiting a friend this summer who should be able to help with that.

[frinky]

Originally Posted by Roy C

You will capture more detail with a converter than cropping heavier - you may be able to crop and get a sharpish shot but you will never be able to put detail into a shot that was not there to begin with! so NO, cropping is not a substitute for more focal length.

Adding a converter will also degrade image quality to some extent, reduce the amount of light (and so increase noise or shake from lower shutter speeds), reduce autofocus speed and accuracy or lose autofocus completely, and make it harder to keep moving subjects in frame if you're close enough. All of which can end up with a shot with less detail than cropping.

That said with suitable conditions and care one should get better results, there is a nice comparison half way down this page but there's no free lunch (with a 500/4 almost welded to a 1.4iii I wish there was ;0).

[Roy C]

Originally Posted by frinky

Adding a converter will also degrade image quality to some extent, reduce the amount of light (and so increase noise or shake from lower shutter speeds), reduce autofocus speed and accuracy or lose autofocus completely, and make it harder to keep moving subjects in frame if you're close enough. All of which can end up with a shot with less detail than cropping.

That said with suitable conditions and care one should get better results, there is a nice comparison half way down this page but there's no free lunch (with a 500/4 almost welded to a 1.4iii I wish there was ;0).

I agree to a certain extent but remember the 300/2.8 is just about the very best lens for taking converters. There are obvious things to bare in mind when using a converter like using a faster shutter speed than you would with the bare lens, It can also pay to use good support (which is why I always used a tripod when using a 2x tc on the 300/2.8 IS), also stopping down a bit almost always helps when using a converter - even with the 300/2.8 + 1.4x tc I usually stopped down to f5.6.

With the 300/2.8 + 1.4 tc the AF is still lighting fast and the IQ loses almost nothing (still at f4 so AF is still good) . As for moving subjects I always use AI servo and back button focusing which helps a lot IMO. When using the 300/2.8 + 2x tc using a focus limiter helps enormously with AF speed of course.The one area where I never found the 300/2.8 + 2x that good was BIF (OK for slow flyers but that's about all) by all accounts the new 300/2.8 MkII lens + MkIII 2x tc is now making BIF a lot better. At the end of the day if one is not going to use converters with the 300/2.8 then you just as well get rid of them, there are of course certain lenses where I would never advocate using a tc with but that's another debate.

Like you said, with care you will get better results than cropping. BTW I am the worlds greatest cropper myself and often use web images at near 100% crop - I even used to crop fairly heavily when using a 2x tc at times (see also the Coot shot in my previous post which was taken with stacked converters and is still heavily cropped LOL).
There are certain lenses that I would never advocate using a tc with but if you are not going to use them with the 300/2.8 then you just as well get rid of them.

[andrew_s]

Cropping vs Converters:

A lens is capable of a certain spatial resolution. If you add a converter to a lens, the spatial resolution of the final image will be reduced by the converter strength (i.e halved for a 2x converter), plus a little for any aberrations introduced by the converter itself.
If the lens produces an image with blurs, a converter will result in an image with bigger blurs.

A sensor is capable of recording up to a certain spatial resolution. The smaller the pixels, the higher the spatial resolution it will record.

If the bare lens will produce a higher resolution than the sensor will record, then there is extra detail available and a converter is worthwhile, but if the lens resolution is lower than the sensor resolution, there's no point in paying for a converter and you may as well crop.

Thus, if you have a basic £200-£400 70-300 lens, a converter is pointless.
If you have a stellar 300/2.8, converters are well worth the money.
In between, you would probably find that a 100-400 would make a 1.4x converter worthwhile on a 30D, but if you use a 7D, it's marginal whether a converter is worth the money.

[Roy C]

I must admit I know nothing about spatial res but what you say certainly make sense Andrew. The piece about "A sensor is capable of recording up to a certain spatial resolution. The smaller the pixels, the higher the spatial resolution it will record." is very interesting and something I have never thought about before in relation to converters.
I have both a 40D and 7D so what you are saying is that the 40D should produce the best results when using a converter - I may make a few test shots in controlled conditions to try this out with my 400/5.6 (which I rarely use with converters for obvious reasons)

I have always taken a very simple approach and gone mainly by the speed and type of lens when it comes to using converters,
In general I find:-

Primes are better than zooms - that not to say that you cannot get good results with a zoom and converter, some of the f2.8 zooms are pretty good these days and I sometimes use a 70-200/4 IS with a 1.4x tc with reasonable success.

for a 1.4x tc you need f4 or faster for best results - f5.6 lenses are very marginal IMO

For a 2x tc you need f2.8 - with f4 lenses being marginal.

[Gazzajagman]

There's another consideration with all teleconverters, the AF speed and accuracy is generally reduced when compared to the native lens. If I'm trying to capture a bird in take off or a bird in flight, then using a cropping method will offer greater AF capacity over a teleconverter option. The image will be brighter too, meaning less reliance on a higher ISO but as Andrew pointed out, the pixel resolution will be lower. With a lens like a 500mm f4 IS L, the reduction in AF Speed and optical resolution are still within the usable limits of the lens/camera/getting-the-shot requirements. But compared to a consumer zoom, only the photographer can decide where their compromises are and what is tollerable.
In recent months, I've questioned my need for a 7D against a cropped 5DIII image. The cropped image is a lot smaller (approx 8mp compared to 18mp from the 7D). AF wise, the 7D is better at tracking the higher effective magnification, the 5DIII is fantastic but it's tracking a larger area...although the spot focus feature is extreamly good. But were the 5DIII excels over the 7D is with it's ISO handling. I'm not happy with the banding and general noise over 400 iso, but the 5DIII is really usable upto and beyond 1600 iso.
Adding a 1.4x to a 5DIII doesn't quite offer me the same reach as a native 7D's 1.62x crop. Add the lower AF capability and reduced Image Quality (blurring, vignetting and lowered contrast), it's not an easy choice and certainly the shooting conditions have a large factor to play.

[shanagan99]

My camera is the canon 60 D with canon 300 2.8 is lens !! what is a focus limiter and how does it work please ?

[hampers]

Originally Posted by shanagan99

My camera is the canon 60 D with canon 300 2.8 is lens !! what is a focus limiter and how does it work please ?

Its one of the controls on the lens itself. On my 300f2.8 it has 3 settings, 2.5m to infinity, 6.5m to infinity and a mid range. Speeds af up considerably.

Phil

[shanagan99]

I was hoping u could limit the infinity distance because when i try and catch birds in flight it goes miles to far so i have to keep refocussing on a near distant object to bring the lens back to somewhere near the distance required ! as u gathered i am new to photography but am getting some great quality pics ..just need info rather than waste money un necessarily ..... seems the 2x extender is a good thing if used when needed ! would you agree ?

[hampers]

Originally Posted by shanagan99

I was hoping u could limit the infinity distance because when i try and catch birds in flight it goes miles to far so i have to keep refocussing on a near distant object to bring the lens back to somewhere near the distance required ! as u gathered i am new to photography but am getting some great quality pics ..just need info rather than waste money un necessarily ..... seems the 2x extender is a good thing if used when needed ! would you agree ?

I use the MkIII 2x 90% of time on my lens and its excellent. Do use the 300 sometimes for bif if they are close enough. Personally no qualms about using one, check out Roy C website he has some outstanding examples of using extenders.

Phil

[frinky]

Originally Posted by shanagan99

I was hoping u could limit the infinity distance because when i try and catch birds in flight it goes miles to far so i have to keep refocussing on a near distant object to bring the lens back to somewhere near the distance required ! as u gathered i am new to photography but am getting some great quality pics ..just need info rather than waste money un necessarily ..... seems the 2x extender is a good thing if used when needed ! would you agree ?

I find two options greatly reduce the number of times my camera focuses on the background when capturing BIF. The first is to use back-button focusing, the advantage being that once you've achieved focus let go of the back button while you take the shots (obviously more useful when the bird is flying parallel to you rather than to/away from you). On a 60D "C.Fn. IV-1 AF and metering buttons" set to 1 I think.

The other is to use the "C.Fn. III-1 Lens Drive when AF Impossible" option set to 1 Stop Focus Search. While you're focusing on a bird and stray on to the background, if it's a relatively featureless sky/clouds the camera won't hunt for focus, just stay where it is. The downside is the camera is less likely to lock on to things you do want, particularly if they're very far in front/behind of the current focus point.

My success with BIFs increased greatly after using these options (I have the Lens Drive when AF Impossible function in my user menu so I can quickly turn it on or off). You could register some of these BIF-specific settings, along with a suitable shutter speed etc in the camera user settings for use with the 'C' mode on the top dial (see bird, spin dial to C, start shooting).

[Lisa W]

For the time being the new 300 2.8 is out of reach. I decided to go ahead and buy the 2X III so that if/when I do trade up in lenses it will work well a newer model lens.
Anyway, converter arrived today, to late for the morning feeding frenzy in the yard, and late enough for the sun to be a real bother. Still, being the impatient soul that I am, I couldn't wait to try it. Attached are 3 shots that I took with the lens today. The third photo is a part of a statue from the back yard that I took since it was stationary (windy today so the birds were swaying a bit back and forth). I focused on the birds eyes, and the center circle on the statue. Overall for now I am satisfied with the converter. Definitely gets me closer with the 400mm.
I definitely appreciate all of the help and advice I received.
Lisa

[johnf3f]

Originally Posted by Lisa W

For the time being the new 300 2.8 is out of reach. I decided to go ahead and buy the 2X III so that if/when I do trade up in lenses it will work well a newer model lens.
Anyway, converter arrived today, to late for the morning feeding frenzy in the yard, and late enough for the sun to be a real bother. Still, being the impatient soul that I am, I couldn't wait to try it. Attached are 3 shots that I took with the lens today. The third photo is a part of a statue from the back yard that I took since it was stationary (windy today so the birds were swaying a bit back and forth). I focused on the birds eyes, and the center circle on the statue. Overall for now I am satisfied with the converter. Definitely gets me closer with the 400mm.
I definitely appreciate all of the help and advice I received.
Lisa

Hope you are pleased with the Mk3 converter - I am with mine and I am using it on F4 lenses - not normally recommended!

[Lisa W]

John, I am pleased. Haven't really got to play with it yet as work has overtaken me. But I think I'll get some good use out of it.

[arthursc]

When you consider that you can get a good S/H MKII for under £300 and from trusted retailers I can't see the point for a hobbist getting the MK III.

i'd rather pocket the extra and put in the jam jar for a higher spec lense.

regards
Colin