Does my lens need calibration?

I am playing around with my 70-200 IS, and I am not quite happy with the image quality. I don't know if it is me, or the lens, or the camera, and it is not as sharp as I expected. From this site, the 100% crop on ISO chart shows that it should be as sharp as the 50 F1.4 @ F2.8. However, I can tell my 50mm is sharper. Here are some test shots. All photos taken on a cloudy day with my XS, center point focus, hand held, IS on, @ 200mm F/4, shutter speed faster than 1/300s, without lens hood, with a Hoya Pro 1 digital UV filter. I test it with live view, zoom in and MF, and can't get better picture. So, I don't think it is focusing issue. Also, I did other test with and without UV filter, image is about the same. So, I don't think it is because of the filter also.

The images are view using Canon DPP, then zoom in 100%, and do a print screen.

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

I can't see any of your images.

Sorry ... I am modifying because the images are too small. I updated it. And here are 2 more. These 2 are taken with hood and UV filter on.

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

Hmm. The picture of the stop sign bolt is fine. The others aren't entirely ok, although passable.

I think you are experiencing the fact that the 70-200 F/4L IS at 200 mm is not as sharp close to MFD as it is slightly further away. At shorter FLs it excels at shorter distances too.

Furthermore, I doubt it is sharper than the 50 F/1.4 at F/2.8. Similarly sharp, yes. It does show CA, while the 50 doesn't. The 50 has slightly less contrast, yes, but contrast only adds apparent sharpness. And the 70-200 at 200 is a different type of lens than the 50 mm at 50 mm. You can't compare the two: 200 mm is 4X linear magnification compared to 50, which means 16X in area. IOW, you only see 1/16 of the frame taken with the 50 from the same spot.

I'd suggest you try a little USM on your semi-macro shots, and see how that works out.

Kind regards, Wim

Yes, only the stop sign bolt looks good ... And here are a couple more to explore the effect of filter. And pictures are taken with hood, with tripod, IS off, shoot with timer, @200mm F4. With and without filter are about the same. So, I conclude it is not because of my filter. My ultimate question. Is it normal? If not, I am going to send it to Canon.

1st - without filter, 2nd - with filter.

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

gte357s wrote in post #8465848
Yes, only the stop sign bolt looks good ... And here are a couple more to explore the effect of filter. And pictures are taken with hood, with tripod, IS off, shoot with timer. My ultimate question. Is it normal? If not, I am going to send it to Canon.

without filter


with filter

It is reported as being normal by several people. Personally, I have never noticed anything like this. When I do semi-macro ro macro with the 70-200 I normally use F/8 or smaller apertures.

However, from the few close-up shots I have done at 200 mm with my specimen, I would say mine is slightly sharper at 200 mm close to MFD.

BTW, you do need a sturdy tripod at 200 mm, I don't know what you use, obviously, but even a good tripod in a little wind at only 50 mm will result in slight blur caused by oscillations induced by the wind.

Kind regards, Wim

Thanks for your reply. Yes, my tripod is not a sturdy one ... I tried increase to F5.6, no significant improve. Let me try F8.

gte357s wrote in post #8465906
Thanks for your reply. Yes, my tripod is not a sturdy one ... I tried increase to F5.6, no significant improve. Let me try F8.

If your tripod is not a sturdy one, try putting the camera on a table or chair, the floor even. A test with a tripod that isn't sturdy essentially invalidates any conclusions about sharpness from tthat test.

Kind regards, Wim

The last two with police car is so much worse than other images. Why would it be ?

gte357s wrote in post #8465416
I am playing around with my 70-200 IS, and I am not quite happy with the image quality. ... Here are some test shots. All photos taken on a cloudy day with my XS, center point focus, hand held, IS on, @ 200mm F/4, shutter speed faster than 1/300s, without lens hood, with a Hoya Pro 1 digital UV filter. I test it with live view, zoom in and MF, and can't get better picture. So, I don't think it is focusing issue. Also, I did other test with and without UV filter, image is about the same. So, I don't think it is because of the filter also.

The images are view using Canon DPP, then zoom in 100%, and do a print screen.

STOP!!!! You are reviewing images at 100%...from an XS that means that (assuming you are using a 1280 pixel wide 19" monitor with about 15" long dimension) the image you would be seeing is as if you were looking from about 24" at a print which had been magnified about 52x, to a final size of 31 x 46" and no sane person would expect razor sharpness at the magnification (yes, insane dSLR users think it should be sharp at super magnification).

What does it look like if you simply fill your monitor with the full image? Bluriness at that nominal magnification about about 16x should not be objectionable.

Vad wrote in post #8466053
The last two with police car is so much worse than other images. Why would it be ?

Well, I don't know. Maybe because it is closer to the car. Or maybe because of the tripod not sturdy enough. For those shots, I use tripod, IS off, and use a timer to reduce shake.

Wilt wrote in post #8466144
STOP!!!! You are reviewing images at 100%...from an XS that means that (assuming you are using a 1280 pixel wide 19" monitor with about 15" long dimension) the image you would be seeing is as if you were looking from about 24" at a print which had been magnified about 52x, to a final size of 31 x 46" and no sane person would expect razor sharpness at the magnification (yes, insane dSLR users think it should be sharp at super magnification).

What does it look like if you simply fill your monitor with the full image? Bluriness at that nominal magnification about about 16x should not be objectionable.

Well .. without zoom in, it looks ok, but I can still see a difference compare to my 50mm, and still not as sharp as I expect by seeing other people's picture. For example, the shot of an owl and other photos in this page. Those are what I am expecting. So, I don't know if it is my skill, or the camera, or the lens.

Here I set up a 'test', using a row of VCR tape boxes, with each box set forward (closer to the camera, from left to right) by 1/2". I placed a ruler against the box fronts, at an incline to the focal plane, to aid in assessment of focus. I aligned the 9" mark of the ruler to the box front which I used as a focus target. In this example, I put the 70-200 f/4L IS lens at 70mm f/4, I was 7' away from my target object. This was shot at ISO 400, with 1/160 (over 2x the FL value, since you have a tripod which might be questionable, the speed I used was higher than the hand holding guideline!)


Here is the full image taken (resized to 900 x 600 for POTN posting)...

I am very confused now. It seems it is not because of the lens. I somehow can get some sharp photos. Now, it seems it is the limitation or nature of the lens or camera. And no matter how I try, can't get a sharp image of the police car. So, it seems it is the AF system of my camera. It seems I can't expect this lens to do macro type of work. Here are some more shots.

A shot to simulate the video tape test (fit to screen, 50% and 100% crop). The 50% crop still very sharp, but becomes soft viewing at 100%

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

A couple more.

A soft image at 100%

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

HTTP response: NOT FOUND | MIME changed to 'image/jpeg'

Is this image sharp enough by the stands of this lens?