difference in exposure btw 2 lenses


Jan 10, 2010
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#1
hi need some advises here, couldnt find any thread regarding this.

i took a spot with the same settings, shutter speed, aperture with oly 17mm f2.8 and a pana 14-45mm f3.5.
the oly lens turn out to be more over exposure than the pana under the same settings.
is it due to the specs of the lens? or i just have to play ard with e shutter speed to compensate?
on top of tt i drop e oly lens from knee level, it does worrry me alittle.
 

daredevil123

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Oct 25, 2005
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lil red dot
#2
hi need some advises here, couldnt find any thread regarding this.

i took a spot with the same settings, shutter speed, aperture with oly 17mm f2.8 and a pana 14-45mm f3.5.
the oly lens turn out to be more over exposure than the pana under the same settings.
is it due to the specs of the lens? or i just have to play ard with e shutter speed to compensate?
on top of tt i drop e oly lens from knee level, it does worrry me alittle.
Did u turn off auto iso?
 

Rashkae

Senior Member
Nov 28, 2005
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#3
What focal length, what metering, what aperture, Auto ISO on or off?
 

Jan 10, 2010
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#4
Focal length at 17mm
f4.0.
ISO set at 250.
Metering at ESP.
 

sw99x

New Member
Jul 10, 2011
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#5
are u in manual mode? you fixed all the above settings, and then took the shot using the 2 lens?
if so, then its right. because the f2.8 lens lets in more light, thus overexposed.
 

Jan 10, 2010
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#6
are u in manual mode? you fixed all the above settings, and then took the shot using the 2 lens?
if so, then its right. because the f2.8 lens lets in more light, thus overexposed.
Yup, manual mode.setted everythin n shoot e same spot. Oh icic.. Tts just ease my worries =)
 

edutilos-

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Dec 28, 2010
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#7
are u in manual mode? you fixed all the above settings, and then took the shot using the 2 lens?
if so, then its right. because the f2.8 lens lets in more light, thus overexposed.
This doesn't seem right.

The f/2.8 lens lets in more light at f/2.8.

But he set both lenses at f/4.0.

Suggest TS post the two photographs with EXIF intact.
 

Rashkae

Senior Member
Nov 28, 2005
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#8
are u in manual mode? you fixed all the above settings, and then took the shot using the 2 lens?
if so, then its right. because the f2.8 lens lets in more light, thus overexposed.
Definitely not right if both lenses are set to f/4. Then it should be identical
 

Jan 10, 2010
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#9
Shutter 1/5sec
Focal Length 17mm
Aperture F4.0
ISO 250
White balance Auto


Taken from Oly 17mm F2.8


Pana 14mm-35mm F3.5



looks identical after posting online though.. from the camera & window looks different
 

Last edited:
Mar 1, 2012
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#10
Probably an issue of same f value but different t value? After all, one is a zoom lens with more elements. Coating also affects.

Also could be flare (or lack of it) issue due to lens design.

But in any case, not a deal breaker right?
 

daredevil123

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Oct 25, 2005
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#11
Shutter 1/5sec
Focal Length 17mm
Aperture F4.0
ISO 250
White balance Auto

Taken from Oly 17mm F2.8

Pana 14mm-35mm F3.5

looks identical after posting online though.. from the camera & window looks different
Looks like a very small difference on my screen. There is a difference, the pana is darker, but very slight.
 

splim

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May 6, 2006
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#12
Shoot with different Aperture should show different results if you worry Aperture malfunction.

Other than that, it's external factors, e.g. add-on filter(s)
 

Jan 10, 2010
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#13
Yes, e background is slightly darker from e pana.

Splim, so a filter might be able to solve the glare?? N what abt e aperture? I shld try other aperture?
 

splim

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May 6, 2006
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#14
Yes, e background is slightly darker from e pana.

Splim, so a filter might be able to solve the glare?? N what abt e aperture? I shld try other aperture?
If there's a filter on the 14-45mm, your photo will be darker if it reflect off too much light, most likely from cheap filter.

Aperture means if you worry it's not working correctly, shoot from F2.8, 3.1, 3.5…. to F22, you should see the different from each setting.


Your lens should be ok but your test result could be cause of:
- Inferior filter(s) fitted on the lens, removed them.
- Shooting with sun light, you should know sun lights are not consistent when cloud passed by.
 

pinholecam

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Jul 23, 2007
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#15
Might be the difference in T-stop. (ie. how much light is loss in transmission passing thru the elements and design).
F-stop is just a function of focal length and aperture diameter.
Could also be design/test tolerances.
 

rhino123

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Sep 1, 2006
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#16
Actually... I don't see too much of a difference. Do note that both lenses shared different

1) Optic elements and element manufacturing
2) Coating
3) Manufacturing tolerance.

Do note that even with the same lens but different copy, you might also achieve very little differences between both lenses... so there really is nothing to worry about. Just know the characteristic of your lenses and adjust accordingly.
 

edutilos-

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Dec 28, 2010
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#17
It's not that different to be alarming. Just relax and enjoy your photography... No need to spend too much time comparing output unless it affects your shooting.
 

pinholecam

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Jul 23, 2007
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#18
It's not that different to be alarming. Just relax and enjoy your photography... No need to spend too much time comparing output unless it affects your shooting.
+1
Not big enough a diff, to matter.
Both are not the most expensive/notable of lenses in the m4/3 stable to loose hair over.

Just compose and take photos with them as what you've done so far :)
 

pinholecam

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#19
It's not that different to be alarming. Just relax and enjoy your photography... No need to spend too much time comparing output unless it affects your shooting.
+1
Not big enough a diff, to matter.
Both are not the most expensive/notable of lenses in the m4/3 stable to loose hair over.

Just compose and take photos with them as what you've done so far :)
 

Jan 10, 2010
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#20
thanks for all e advises =))

been playing around with the settings. however i notice the ghosting gets worst when i set e apenture higher.
other than tt everything is fine intially i tot was the drop tt cause the difference.
 

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