canon 70-200 f2.8L IS II USM , need lens test

[Saffa]

Hi every one here ..

I'm kinda new in photography , i have this lens and not sure if it is sharp enough !

this photo is taken using tripod and timer so i guess there is no shake , i feel it is not sharp enough can you help me please ? is there any way to test the lens ?

please excuse my English .

lens 70-200 f2.8 IS II USM
aperture F4
shutter speed 1/4 sec
focal length 200mm

thanks

 

[jaomul]

Hard to say how sharp it is as uploaded photos may take a hit. Did you use autofocus or manual, if manual are you sure it's bang on, you might be to close for the lens to focus correct. Also you're at 1/4 second, I know you're on a tripod but did you use a timer or release cable, touching the shutter button on camera might just move it enough to give a not sharp photo

 

[robbins.photo]

A lot of factors influence the sharpness of the final photo. Using the tripod and timer to avoid camera shake helps, but you can achieve the same by using a higher shutter speed without the need for a tripod and timer. For a 70-200 mm lens if you keep your shutter speed to at least 1/200 you generally eliminate any problems with camera shake. If possible i like to double that and shoot at 1/400 when possible, i find it makes for nice sharp photos but of course you need to be mindful of your aperture and ISO depending on the shooting conditions.

But there are other factors involved as well, such as your distance from the object being photographed and your aperture settings. These influence your depth of field. A narrow depth of field will cause objects further away or closer than whatever the focal point chosen by the camera might have been to be blurrier than the focal point is, and of course the more narrow your depth of field the blurrier these will become.

As a general rule increase your aperture setting or "stopping down" the lens will give you more DOF and result in more of the photo appearing sharp, however again you have to balance this against your ISO and shutter speed settings to get the best results.

 

[Saffa]

thanks for your reply ... i used a timer to get rid of hand shack and auto focus ...
here is another photo taken from distance about 4 to 5 meter from subject

1/400 sec
iso 800
f 2.8
auto focus , spot metering if possible take a look oni it and i know its hard to say but is the sharpness acceptable for this photo ?

 

[manaheim]

Looks plenty sharp to me. On the first one it looks like your plane of focus is on the protector covering the lens on whatever that thing is. The specs of dust there are sharp.

Keep in mind higher ISO is going to affect your shots as well, and keep in mind that the lens is not going to be its sharpest at extremes of zoom and extremes of aperture. (So 2.8 is not going to be the sweet spot).

Lenses vary, but usually a couple stops down from wide open and about 1/3 zoomed in is where you're going to see the best from most lenses.

Finally, keep in mind that most digital cameras (yours included from the looks of it) have a physical anti-aliasing filter that are designed to intentionally soften the image. Strengths of these filters vary by quite a bit. You almost always want to run a sharpening pass on an image when taking it.

Finally finally, pixel peeping is almost always a bad idea. Particularly on a lens you just got.

 

[TCampbell]

You really need to use a focus target to evaluate performance.

It's an extremely good lens and, overall, probably the best 70-200mm f/2.8 in the industry (it's the only one that doesn't have a massive "breathing" problem.) But to evaluate focus accuracy you really need to use a target that can show if the camera is either front-focusing or back-focusing.

Here's an example...

I'm focused on that high-contrast target in the center of the image. The scale on the right side of the target is actually leaning back at a 45º angle tilting away. The "0" point on the scale is at the same distance as the high-contrast focus target. Everything below the zero is technically closer to the camera. Everything above the 0 is technically farther away from the camera.

When I tested this particular lens (this is a Canon EF 50mm f/1.2L USM) on my 5D III body I found that the lens was nailing the focus every time. But when I test this SAME lens on my 5D II body, I found that it was very slightly back-focusing and I had to change the auto-focus micro-adjustment by -2 units to achieve consistently accurate focus. (this is a small 1024 px wide image. But in the full resolution version you can zoom right in and check the focus accuracy.) Each camera can be different... which is why I test my lenses and enter the focus calibration for each body.

In your image, it "looks" nicely focused. When I zoom in it looks like it might be just a very tiny bit soft. But I can't tell if it's camera shake because you used a 1/4 second exposure time and even the mirror slap can cause that. The tripod has to be rock solid (the tripod I use for this tests are very beefy, heavy, "you wouldn't want to have to carry it on a long hike" tripods.) You can enable mirror lock-up mode on the camera (this requires that you press the shutter button twice... the first press swings up the mirror and lets the vibration settle... the second press takes the shot.) And of course just touching the camera to press the shutter button will induce some vibration.