Problem with Nikon 50mm 1.8 AF

On Feb 23, 2:35 pm, Paul Furman <pa... DeleteThis @-edgehill.net> wrote:
> Nicholas O. Lindan wrote:
> > "Paul Furman" <pa... DeleteThis @-edgehill.net> wrote
> >> "Steve" wrote
> >>> [50mm/85mm lens is/isn't stopping down correctly]
> >> If the aperture blades were sticking it'd be overexposed
>
> > Might it be possible that the aperture blades are sticking -
> > but on the 85mm: the 50mm is working OK but the '85 is
> > overexposing 1 stop?
>
> > Very strange, though.
>
> > Questions:
>
> > 1) If the lenses are demounted and you look through the lens as
> >    you turn the aperture ring do they both stop down about the
> >    same amount for each click of the ring?
Shooting a D50 in fulkl manual mode, outdoor (although same prob
occurs when using flash). The 85 actually seems to overexpose just a
tad relative to the kit lens, and I've had to use it at around -.3 or
-.7 to produce the best results. I tried setting shutter speed to
1sec, then look actuallyt watch the aperture close for all settings
between 1.8 and the max for each lens, and it doesn't look like
anything is sticking. I was wondering if something might actually be
miscalibrated?
Thanks.
-Steve



> > 2) If you set the rings for f8 and then slowly open and close
> >    the aperture with the aperture pin do they close down to
> >    same point all the time, what if the pin is flicked?
>
> > 3) What camera are you using and what mode is it on?
>
> 4) Does it underexpose wide open or only at certain apertures?
>
> Vignetting will make the corners somewhat darker when wide open but the
> center should be OK.- Hide quoted text -
>
> - Show quoted text -
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

Oh, and so far, this underexposure appears to hold for all apertures.
I think I will try to borrow a friend's 50mm, and see if the same
thing occurs...
-Steve
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

"Paul Furman" <paul-.RemoveThis@-edgehill.net> wrote
> "Steve" wrote
> > [50mm/85mm lens is/isn't stopping down correctly]
> If the aperture blades were sticking it'd be overexposed

Might it be possible that the aperture blades are sticking -
but on the 85mm: the 50mm is working OK but the '85 is
overexposing 1 stop?

Very strange, though.

Questions:

1) If the lenses are demounted and you look through the lens as
you turn the aperture ring do they both stop down about the
same amount for each click of the ring?

2) If you set the rings for f8 and then slowly open and close
the aperture with the aperture pin do they close down to
same point all the time, what if the pin is flicked?

3) What camera are you using and what mode is it on?

--
Nicholas O. Lindan, Cleveland, Ohio
Darkroom Automation: F-Stop Timers, Enlarging Meters
http://www.darkroomautomation.com/index.htm
n o lindan at ix dot netcom dot com
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

Nicholas O. Lindan wrote:
> "Paul Furman" <paul-.TakeThisOut@-edgehill.net> wrote
>> "Steve" wrote
>>> [50mm/85mm lens is/isn't stopping down correctly]
>> If the aperture blades were sticking it'd be overexposed
>
> Might it be possible that the aperture blades are sticking -
> but on the 85mm: the 50mm is working OK but the '85 is
> overexposing 1 stop?
>
> Very strange, though.
>
> Questions:
>
> 1) If the lenses are demounted and you look through the lens as
> you turn the aperture ring do they both stop down about the
> same amount for each click of the ring?
>
> 2) If you set the rings for f8 and then slowly open and close
> the aperture with the aperture pin do they close down to
> same point all the time, what if the pin is flicked?
>
> 3) What camera are you using and what mode is it on?

4) Does it underexpose wide open or only at certain apertures?

Vignetting will make the corners somewhat darker when wide open but the
center should be OK.
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

"Steve" <srjm72499 DeleteThis @gmail.com> wrote in message
news:d1b1862c-2b82-40d7-9a24-a09a27b1d2fa@q33g2000hsh.googlegroups.com...
> Oh, and so far, this underexposure appears to hold for all apertures.
> I think I will try to borrow a friend's 50mm, and see if the same
> thing occurs...
> -Steve
>
Try putting the camera on manual mode, opening the lens all the way, and,
using a light meter, adjust the lighting until the exposure should be right
on the money.....Then see how the pictures come out.

And, even before those pictures are developed, put another lens on the
camera and do the same thing. Are the adjustments different for the same
lighting level? If they are, then look for a filter on the front of the
lens. If no filter, then the lens must be defective.....Someone must have
messed with the elements, or put a coating on one of them......Or, the
aperture adjustments must have been messed up upon reassembly......Does the
aperture scale go all the way at both ends? i.e.: can you close it down all
the way, as well as open it up all the way?
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

"William Graham" <weg9 DeleteThis @comcast.net> wrote in message
news:lPidnWhQMaeACl3anZ2dnUVZ_vyinZ2d@comcast.com...
>
> "Steve" <srjm72499 DeleteThis @gmail.com> wrote in message
> news:d1b1862c-2b82-40d7-9a24-a09a27b1d2fa@q33g2000hsh.googlegroups.com...
>> Oh, and so far, this underexposure appears to hold for all apertures.
>> I think I will try to borrow a friend's 50mm, and see if the same
>> thing occurs...
>> -Steve
>>
> Try putting the camera on manual mode, opening the lens all the way, and,
> using a light meter, adjust the lighting until the exposure should be
> right on the money.....Then see how the pictures come out.
>
> And, even before those pictures are developed, put another lens on the
> camera and do the same thing. Are the adjustments different for the same
> lighting level? If they are, then look for a filter on the front of the
> lens. If no filter, then the lens must be defective.....Someone must have
> messed with the elements, or put a coating on one of them......Or, the
> aperture adjustments must have been messed up upon reassembly......Does
> the aperture scale go all the way at both ends? i.e.: can you close it
> down all the way, as well as open it up all the way?
>
There is another possibility.....The mount on Nikkors has a cutout on it
that tells the camera what the speed of the lens is......I forget just where
it is, but they mill a depression somewhere that tells the camera
this.....It could be that the lens has the wrong mount on it, or the
depression is filled up with crud, or something is wrong here, so the camera
thinks your lens if faster than it really is......
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF 

Steve try taking a reading of a white sheet o f paper which has even
illumination . Do not use matrix metering .

The Photographs you are taking the 50mm will include more "sky" and cause
the metering to under expose.
Are you using digital or Film. With Film te printers tend to compensate



"Steve" <srjm72499 DeleteThis @gmail.com> wrote in message
news:abe7f10c-ca50-4f75-af71-7b97b0f1afa6@q78g2000hsh.googlegroups.com...
>I recently purchased two used lenses from different sources, and just
> received them in the mail (yea!). Both are nikon: 85mm and 50mm 1.8
> lenses. However, when comparing images from the two, I'm noticing that
> the 50 is consistenly 1 exp position underexposed. I can compensate in
> the auto modes by bumping up the exposure, so I first thought this
> might just be a meteringt thing. However, I just tried a comparison
> shooting outdoor shots in full manual. For the same shutter speed
> (1/60), f/8 ap on the 85 gave the same as f/5 for the 50mm. f/8 on the
> 50 was a LOT darker...
>
> Is this normal, and if not, what can I do (short of getting rid of the
> lens) .
>
> Thanks.
> -Steve
 >> Stay informed about: Problem with Nikon 50mm 1.8 AF