Metering problem?


Status
Not open for further replies.

rEveRie

New Member
Nov 19, 2005
289
0
0
Nikon
www.robbysucipto.com
I set the my camera, a D200 on aperture priority.

with AF-S 70-200 VR lens, i noticed there is a slight change in exposure between f/2.8 and f/10.
Tested this against various subjects with different tones, and it is consistently giving a slight change of exposure between apertures.

Changed to a AF 35mm f/2 lens, it results the same way.
Changed to a AF-s 12-24mm f/4, it is the same.

I loaded test pictures into nikon capture and observe the histogram, indeed there is a slight shift to the right for the smaller aperture.

I shifted the exposure compensation to mimick similar exposure and it is roughly around 0.10 EV difference between apertures.

I am not sure if this is a problem or it is meant to be this way?
I didn't do such test on my D70...

can some bros advise?
thanks
 

rebbot

Senior Member
Mar 24, 2005
1,828
0
0
rEveRie said:
I set the my camera, a D200 on aperture priority.

with AF-S 70-200 VR lens, i noticed there is a slight change in exposure between f/2.8 and f/10.
Tested this against various subjects with different tones, and it is consistently giving a slight change of exposure between apertures.

Changed to a AF 35mm f/2 lens, it results the same way.
Changed to a AF-s 12-24mm f/4, it is the same.

I loaded test pictures into nikon capture and observe the histogram, indeed there is a slight shift to the right for the smaller aperture.

I shifted the exposure compensation to mimick similar exposure and it is roughly around 0.10 EV difference between apertures.

I am not sure if this is a problem or it is meant to be this way?
I didn't do such test on my D70...

can some bros advise?
thanks
aperture does affect exposure if I understand what you are trying to ask. :)
 

rEveRie

New Member
Nov 19, 2005
289
0
0
Nikon
www.robbysucipto.com
rebbot said:
aperture does affect exposure if I understand what you are trying to ask. :)
hahaa...
pardon me for being unclear.

what I am trying to ask is, under aperture priority, under the same metering mode,
changes in aperture would not result in exposure changes because the shutter speed changes accordingly to achieve the consistent exposure of the same scene.
 

Zerstorer

Senior Member
Jul 8, 2002
3,438
0
36
Almost all lenses have slight exposure variations/inconsistencies across apertures. It would be the same on a D70 or a D2x.
 

rEveRie

New Member
Nov 19, 2005
289
0
0
Nikon
www.robbysucipto.com
Zerstorer said:
Almost all lenses have slight exposure variations/inconsistencies across apertures. It would be the same on a D70 or a D2x.
phew... glad to hear that.
thanks.

i tested on a canon A95 point and shoot, it doesnt seem to experience this tho'.
haha. anyway, i guess it's different since the lenses is made specifically for that body.
 

roti_prata

New Member
Jul 31, 2005
768
0
0
Bt Batok
rEveRie said:
the shutter speed changes accordingly to achieve the consistent exposure of the same scene.
the shutter speed cannot change accurately enough. for example 1/9.8 sec is required for identical exposure but the closest the camera can do is 1/10 so the pic will be slightly darker
 

rEveRie

New Member
Nov 19, 2005
289
0
0
Nikon
www.robbysucipto.com
roti_prata said:
the shutter speed cannot change accurately enough. for example 1/9.8 sec is required for identical exposure but the closest the camera can do is 1/10 so the pic will be slightly darker
yepz, I have considered this issue as well.
Do you think this is the predominant factor as compared to lens inconsistency?

I tried across faster shutter speeds and the results is the same, I understand that faster shutter speeds does not go down to exact number as well.
 

Zerstorer

Senior Member
Jul 8, 2002
3,438
0
36
roti_prata said:
the shutter speed cannot change accurately enough. for example 1/9.8 sec is required for identical exposure but the closest the camera can do is 1/10 so the pic will be slightly darker
No, shutter speeds are almost stepless. It's just the displays are rounded up to simplify matters.
 

rEveRie

New Member
Nov 19, 2005
289
0
0
Nikon
www.robbysucipto.com
just checked the images downloaded from the canon point and shoot camera, A95.
there is indeed slight shift of exposure as well.
from f/4 to f/8

same phenomena.
 

espn

Deregistered
Dec 20, 2002
21,899
0
0
Planet Nikon
Why worry so much.. just shoot first, talk later.
 

Status
Not open for further replies.