[SMeK]

Hello.

Is it normal to get visible difference in exposure on different aperature?

Here some examples:

1. 16-45 wide open f4.0



2. 16-45 f6.3



3. DA 35 f4.0 for comprasion



Camarea is K5is, same thing on K-x.

DA 35 is pretty constant, more or less.

Ty.

---------- Post added 18-08-15 at 12:17 ----------

exif

1.

Filename - 1.jpg
Make - PENTAX
Model - PENTAX K-5 II s
Orientation - Top left
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
Software - K-5 II s Ver 1.07
DateTime - 2015:08:18 11:35:39
Artist -
YCbCrPositioning - Co-Sited
Copyright -
ExifOffset - 706
ExposureTime - 1/2500 seconds
FNumber - 4.00
ExposureProgram - Aperture priority
ISOSpeedRatings - 320
ExifVersion - 0230
DateTimeOriginal - 2015:08:18 11:35:39
DateTimeDigitized - 2015:08:18 11:35:39
ComponentsConfiguration - YCbCr
ExposureBiasValue - 0.00
MeteringMode - Multi-segment
Flash - Flash not fired, compulsory flash mode
FocalLength - 34.00 mm
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 1000
ExifImageHeight - 662
InteroperabilityOffset - 54468
SensingMethod - One-chip color area sensor
FileSource - Other
SceneType - Other
CustomRendered - Normal process
ExposureMode - Auto
White Balance - Auto
FocalLengthIn35mmFilm - 51 mm
SceneCaptureType - Standard
Contrast - Hard
Saturation - Normal
Sharpness - Hard
SubjectDistanceRange - Distant view

GPS information: -
GPSVersionID - 2.3.0.0

Maker Note (Vendor): -
Mode - Auto
Quality - 5
ISO - 320
White Balance - Auto
Lens Type - smc PENTAX-DA 16-45mm F4 ED AL

Thumbnail: -
Compression - 6 (JPG)
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
JpegIFOffset - 54610
JpegIFByteCount - 7170

2.

Filename - 2.jpg
Make - PENTAX
Model - PENTAX K-5 II s
Orientation - Top left
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
Software - K-5 II s Ver 1.07
DateTime - 2015:08:18 11:35:43
Artist -
YCbCrPositioning - Co-Sited
Copyright -
ExifOffset - 706
ExposureTime - 1/1250 seconds
FNumber - 6.30
ExposureProgram - Aperture priority
ISOSpeedRatings - 320
ExifVersion - 0230
DateTimeOriginal - 2015:08:18 11:35:43
DateTimeDigitized - 2015:08:18 11:35:43
ComponentsConfiguration - YCbCr
ExposureBiasValue - 0.00
MeteringMode - Multi-segment
Flash - Flash not fired, compulsory flash mode
FocalLength - 34.00 mm
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 1000
ExifImageHeight - 662
InteroperabilityOffset - 54468
SensingMethod - One-chip color area sensor
FileSource - Other
SceneType - Other
CustomRendered - Normal process
ExposureMode - Auto
White Balance - Auto
FocalLengthIn35mmFilm - 51 mm
SceneCaptureType - Standard
Contrast - Hard
Saturation - Normal
Sharpness - Hard
SubjectDistanceRange - Distant view

GPS information: -
GPSVersionID - 2.3.0.0

Maker Note (Vendor): -
Mode - Auto
Quality - 5
ISO - 320
White Balance - Auto
Lens Type - smc PENTAX-DA 16-45mm F4 ED AL

Thumbnail: -
Compression - 6 (JPG)
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
JpegIFOffset - 54610
JpegIFByteCount - 6921

3.

Filename - 3.jpg
Make - PENTAX
Model - PENTAX K-5 II s
Orientation - Top left
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
Software - K-5 II s Ver 1.07
DateTime - 2015:08:18 11:36:21
Artist -
YCbCrPositioning - Co-Sited
Copyright -
ExifOffset - 706
ExposureTime - 1/4000 seconds
FNumber - 4.00
ExposureProgram - Aperture priority
ISOSpeedRatings - 320
ExifVersion - 0230
DateTimeOriginal - 2015:08:18 11:36:21
DateTimeDigitized - 2015:08:18 11:36:21
ComponentsConfiguration - YCbCr
ExposureBiasValue - 0.00
MeteringMode - Multi-segment
Flash - Flash not fired, compulsory flash mode
FocalLength - 35.00 mm
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 1000
ExifImageHeight - 662
InteroperabilityOffset - 54468
SensingMethod - One-chip color area sensor
FileSource - Other
SceneType - Other
CustomRendered - Normal process
ExposureMode - Auto
White Balance - Auto
FocalLengthIn35mmFilm - 52 mm
SceneCaptureType - Standard
Contrast - Hard
Saturation - Normal
Sharpness - Hard
SubjectDistanceRange - Distant view

GPS information: -
GPSVersionID - 2.3.0.0

Maker Note (Vendor): -
Mode - Auto
Quality - 5
ISO - 320
White Balance - Auto
Lens Type - unknown (7, 214; 32, 0)

Thumbnail: -
Compression - 6 (JPG)
XResolution - 300
YResolution - 300
ResolutionUnit - Inch
JpegIFOffset - 54610
JpegIFByteCount - 7296

[BlakeShellman]

I like the one taken at F6.3 better

[Fogel70]

I believe it's normal with minor variation on exposure between shots (1/3 stop difference in exposure as in above examples).
But I don't think it's connected to aperture used. Do you always see the same thing?

As all three shots have slightly different composition it's hard to say what makes the difference. I could be the light meter that makes different decisions because the shots are different. Or it could be some setting you use that make the difference, FI if "link AE to AF point" or "AE-L with AF locked" are enabled.

Do you use the lens hood on DA 16-45? If not, it might be flares that affect the first shot making the lower contrast in the first shot.

[SMeK]

Yes, it happens always. I use hood. I must check AE to AF poind but AE-L with AF locked is not enabled.

---------- Post added 18-08-15 at 14:28 ----------

Third photo is bit different, ignore it, I moved camera when switched lens...

[IchabodCrane]

The metering suggests the 2nd image should be 1/3 stop darker than the first. If you think that 1/3 stop difference is correct (you can check by changing one on your computer by that amount to see if both are then the same) then you can probably conclude the exposure difference is not due to a mechanical issue.