I went out today and tested the 300 2.8 IS+Canon 1.4x Converter. So, on my 1Ds II I had a 420 f/4 IS. I have tested the 300 2.8 IS by itself and it is TACK sharp (even wide open). However, the shots I got at the Wildlife Refuge today were not impressive. All three shots were taken at 420mm and were stopped down 1/3-2/3 of a stop. From the 1.4x reviews, I didn't think I needed to stop down beyond that for sharp images. The photos have been cropped about 50% from the original file. Is the 1.4x I have a bad copy? The shutter speeds for these shots were beyond 1/1000th of a second. ISO was between 320 & 800. My 100-400 @ 400 produced much sharper images than these. Any thoughts would be appreciated.

They seem okay- was this with the 1.4x II or the 1.4x I?
Either way, the 300 2.8 IS itself is too good- whenever you compare the images with the extender to those taken without the extender, they seem worse just by comparison.
Was the focus correct? Or do they seem misfocused slightly?

Right away on the first and third photos I notice just a touch of front focusing.

Will Patterson wrote:
Right away on the first and third photos I notice just a touch of front focusing.

Have to agree with Will here, I noticed the same thing. My 300 f/2.8 + 1.4 will produce a very sharp image.

Did you focus correctly ? What's Cfn 17 set to ? Center point only or....
Were you in Ai-Servo ?
To me , in #1 and #3, you seem fairly close to the birds for the AF to be thrown off...if peripheral AF points were being used. Can you do Zoombrowser and show us the focus points ?

I get very good results with both converters. I seem to get better shots when I over expose a bit especially with the 2x.

With the exception of the 2nd shot, the other two are not good tests for wide open apertures as the subject is nowhere near parallel the sensor. You would definitely need to stop down further in that situation, especially at closer distances.

1 and 3 are front-focused. 2 looks pretty damn sharp to me.

If No. 1 were front focused the tail on the bird would be sharp and it is not. I think they are fine and you have a little camera shake on the first. Your Exif shows it to be the slowest shutter speed of the three.

Lance
www.pbase.com/lancemoreland

This combo can be shot wide open, though it does benefit a tad by being stopped down even 1/3 to 2/3 of a stop as you have mentioned.

Ben Horne wrote:
This combo can be shot wide open, though it does benefit a tad by being stopped down even 1/3 to 2/3 of a stop as you have mentioned.

I also agree.

I think this is a case of slight focus error, not TC softness - that combo is tack sharp.

lancemoreland wrote:
If No. 1 were front focused the tail on the bird would be sharp and it is not. I think they are fine and you have a little camera shake on the first. Your Exif shows it to be the slowest shutter speed of the three.

Lance
www.pbase.com/lancemoreland

The shoulders of both birds are tack sharp, not their eye, so unless he was focusing on their shoulders instead of their eyes, then it's front focusing.

Will Patterson wrote:
Right away on the first and third photos I notice just a touch of front focusing.

+1

Will Patterson wrote:


The shoulders of both birds are tack sharp,

That was my point. The OP doesn't say that he focused on the birds eyes and recomposed. The center of all images are sharp. I think his combo is fine. A little smaller aperture (greater depth of field) and the entire bird would be sharp

Lance
www.pbase.com/lancemoreland

I shoot with that combo all of the time and it's SHARP. Just FYI. Hope you can fix the problem. Take care, Mike

Higher ISO shots are harder to get tack sharp. If you had IS on, did you wait for it to totally engauge PRIOR to taking the shot?

Matt

I'll push what the others have said a bit further: I don't shoot with this combo much, but I shoot with a 2x a lot, and good shots are at least as sharp as this. A 1.4x shouldn't do this to a 300/2.8IS; you've got either a soft TC, some sort of technique problem, or just had dumb luck that day.

To help eliminate focusing error, try shooting multiple shots of the same subject, refocusing after each. The focus preset rocker is handy for this: set it to infinity, then when shooting, touch the rocker, focus, and fire. Repeat this a few times and you're likely to see small variations in focus distance with each shot. One will usually be sharper than the rest.

To eliminate hand shake, keep the shutter speed as fast as possible. With my 5D (similar noise to the 1Ds2) I was happy to shoot ISO800 if it meant I could keep my shutter speed above 1/1000sec. Only when I hit ISO1600 did I notice that image started becoming softer due to noise reduction... and then I'd rather machine gun a bunch of frames and hope IS saved me. That usually works for me down to 1/400sec or so with my 2x. But you should shoot some test shots to see at what shutter speed hand shake is completely eliminated for your hands, and strive to reach that shutter speed.

You might also try shooting from a tripod if you have a stable enough setup for this kit. You can get more repeatable results with a tripod than handheld. And if you've got a willing subject and access to a camera with Live View, you can absolutely NAIL focus, and see what your lens can really do.

Also keep in mind that the super short DOF at long focal lengths mean that focus/recomposing will give you back focus. With your shoulder level with the center of your monitor, reach your arm out and touch the top of your monitor. Now move your arm down so it's horizontal. Your finger would push through the monitor when your arm is horizontal. This is the problem with focus/recompose--you're putting the plane of focus behind the subject. You can mitigate this by selecting a focus point that lets you focus with little/no recomposing.

Finally, FWIW, I notice very little difference in sharpness when stopping down with a 1.4x attached. So little that it's barely worth mentioning. If shooting wide open means you can keep your shutter speed up to your target and shoot ISO400 instead of ISO800, I say shoot wide open. You'll gain more from lower noise than you'll lose from lens softness. So long as that gives you sufficient DOF, of course.

I hope you find some solution that helps your images. Shooting with long tele lenses has a steep learning curve, so experiment liberally, and don't give up!

CKrueger wrote:
I'll push what the others have said a bit further: I don't shoot with this combo much, but I shoot with a 2x a lot, and good shots are at least as sharp as this. A 1.4x shouldn't do this to a 300/2.8IS; you've got either a soft TC, some sort of technique problem, or just had dumb luck that day.



+1

There is marginal difference at best in the "pixel peeping mode" between a 300/2.8 IS only and a 300/2.8 IS + 1.4x. I use the 300/2.8 IS + 2x combination a lot more frequently and this combination is sharp when stopped down a 1/3 or more.

The use of the phrase "front focusing" is misleading and almost certainly wrong here.

It looks to me like the AF point was on the body of the bird in one and three instead of the eye - that's not front focusing.

keithreeder wrote:
The use of the phrase "front focusing" is misleading and almost certainly wrong here.

It looks to me like the AF point was on the body of the bird in one and three instead of the eye - that's not front focusing.

I don't find it misleading, I just think it is implied or assumed that the eye was the focus target.

Marc