Advice: Bump at the back element of the nikon 70-200 lens


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Adzz

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Jun 20, 2004
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Hi, just gotten the 70-200 vr lens today and tried taking some images. Maybe its because I accidentally boosted the ISO up to 800, I notice that this image seems weird.


F2.8 1/125sec VR on, normal

It seems to be sharper at the top then the centre which is supposed to the focusing point. Also, it seem to be brighter at the centre, much brighter, is it a glare?

Secondly, while looking at the lens, the back area of the lens displayed a bump, as shown in the image, will it affect the image quality?




Is this normal of this 70-200 lens?
 

Gymrat76

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May 10, 2004
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Bump is normal, same thing on my lens.

Does the brightness and top-sharpness show up in other photos? Not to be insulting, but is it possible you were using the top focus box? At f2.8 your DoF is rather narrow, perhaps your focus was off?:dunno:
 

Zerstorer

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Jul 8, 2002
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Take more shots, if they all turn out like that, it could be misaligned lens elements.
 

Adzz

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Zerstorer said:
Take more shots, if they all turn out like that, it could be misaligned lens elements.
what are the signs of misaligned lens elements? I will probably be shooting tmrw to try it out? is there any subjects i should focus on to test the lens? or specific apearture etc...
 

ahbeng

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Gymrat76 said:
Bump is normal, same thing on my lens.

Does the brightness and top-sharpness show up in other photos? Not to be insulting, but is it possible you were using the top focus box? At f2.8 your DoF is rather narrow, perhaps your focus was off?:dunno:
a few things i see from the pics:
1) the color seems dull
2) a layer fog at lower part of the pic

to narrow down your investigation, my questions is
1) are all ther other pics like this
2) other lens have this problem

let me know when you find out what is the cause, i am interested to know.
 

gooseberry

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Mar 11, 2004
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Adzz said:
what are the signs of misaligned lens elements? I will probably be shooting tmrw to try it out? is there any subjects i should focus on to test the lens? or specific apearture etc...
Try the same settings as the picture above for a start... you mention that only this pic seems weird - how about other pictures ?
 

Zerstorer

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Adzz said:
what are the signs of misaligned lens elements? I will probably be shooting tmrw to try it out? is there any subjects i should focus on to test the lens? or specific apearture etc...
If one part of the image is persistently sharper at all settings, regardless of aperture or focal point. This should be consistent across all images.
 

Spyer2

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Did you zoom in 200mm with F2.8? Like Gymrat76 said F2.8 the DoF is narrow, I also have problem on the image sharpness when using F2.8 with 200mm. But i do not have the half bright symptom..
 

Adzz

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ahbeng said:
a few things i see from the pics:
1) the color seems dull
2) a layer fog at lower part of the pic

to narrow down your investigation, my questions is
1) are all ther other pics like this
2) other lens have this problem

let me know when you find out what is the cause, i am interested to know.
I guess it is due to the fact that I am using Adobe RGB color profile on the D70, which explains the duller pic. I shot 3 images, all appear to have a growing circle in the middle.

But at iso 200, and a slightly faster shutter speed of 1/100, the color is dull only, but consistent throughout.
 

espn

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Dec 20, 2002
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Dude, check your front filter. The shot looks hazy to me. I took a lot of shots that time using a t-loaned 70-200VR at f/2.8, sharpness is not a big issue for resized images even at 200mm. Your image seems to be a bit dull in colours and hazy.

Alternatively, bring down to NC tomorrow evening :) I can take home and test for you :devil: (j/k)
 

2100

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Mar 3, 2004
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Heh......cannot really see from such a small pic. Maybe you can shoot at a flat piece of thing like a pic on the wall. And bigger please. If it seems hazy, ghosting, most probably a piece of glass element went off the optical axis. I kena before.... What i mean is, you look for lines with high contrast, like white and black edges. Does the white bleed and form a secondary image on the black?

Try to shoot at f5 and other focal lengths, is it gone? Try to shoot in bright light, fast enough shutter (or mount on tripod) with VR turned off first to isolate things first, btw. You need to confirm the optical quality and see if you did not get a lemon copy.
 

Adzz

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Jun 20, 2004
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Hi! I figured that my focusing zone was on top, resulting in the wrong focusing point. That should be the likely reason. As for the glare in the middle, I have no idea why it was so, probably a flare as some of you mention.

I tried this lens yesterday, and it works perfectly, if only I could be more proficient in my M Mode and brought my wide angle lens with me. Haha! Sharpness should be there. I am beginning to like the VR function already. :)
 

sehsuan

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are you sure, that there wasn't a wall or anything that popped up ever so slightly into your view when you shot? it does happen to me...
 

Adzz

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sehsuan said:
are you sure, that there wasn't a wall or anything that popped up ever so slightly into your view when you shot? it does happen to me...
I am pretty sure about the wrong focusing zone that was used, (top instead of the middle). For the flare, the only reason I could think of as what you said, is that I am shooting behind a window, with AL frames, the windows are open. Perhaps, the window frame resulted in that.

I tried the lens outside, no such problems. I guess that night was a major screw up. Hehe... :)
 

marlin

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Adzz said:
I am pretty sure about the wrong focusing zone that was used, (top instead of the middle). For the flare, the only reason I could think of as what you said, is that I am shooting behind a window, with AL frames, the windows are open. Perhaps, the window frame resulted in that.

I tried the lens outside, no such problems. I guess that night was a major screw up. Hehe... :)

perhaps next time when u post , give more details of ur shooting conditions and environment and take more test shots this way ppl would be be able to help better and faster...
 

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