Exposure difference between Live view and ovf when using m42 tak 35mm f/3.5

DeanG · 02-01-2019, 02:19 PM

Very interesting, I can follow that. Thank you! I noticed about a 1 stop difference up to F/8, but at F/11 the exposure readings get closer. I seldom go smaller than F/8so I should be able to set exp comp and store it as a screwmount VF user mode and be good most of the time, or if I am working at a more leisurely pace, meter in live view.

Interesting discussions.

pschlute · 02-02-2019, 03:22 AM

Ok well it doesnt sound like the focus screen. I think you are just going to have to put it down to the defference between the two metering systems.

At least with DSLR's we have the advantage of the histogram. I always have mine displayed in instant preview. You can then quickly make an adjustment to the exposure depending what the histogram is telling you.

Not a Number · 02-02-2019, 05:04 AM

Try putting a bit of metal foil over the contacts. Hold it down with a bit of sticky tape before mounting the Takumar. Green button metering doesn't work on some bodies without an electrical contact on the mount. It shouldn't matter with screwmount but you never know.

Does the imbalance change depending on the scene/target you are shooting? Try using a gray card as the target.

Not a Number · 02-02-2019, 05:04 AM

Try putting a bit of metal foil over the contacts. Hold it down with a bit of sticky tape before mounting the Takumar. Green button metering doesn't work on some bodies without an electrical contact on the mount. It shouldn't matter with screwmount but you never know.

Does the imbalance change depending on the scene/target you are shooting? Try using a gray card as the target.

DeanG · 02-02-2019, 09:19 AM

Thanks, well I shorted out the contacts and the camera thought I was at f/8!

Time to quit worrying about it and take some photos. Easy enough to dial in some exp comp, thanks everyone for the theories and help, but I guess this screwmount lens reveals some difference with LV and VF metering in manual..I can live with that!

pschlute · 02-02-2019, 10:41 AM

Originally posted by DeanG

Thanks, well I shorted out the contacts and the camera thought I was at f/8!

Time to quit worrying about it and take some photos. Easy enough to dial in some exp comp, thanks everyone for the theories and help, but I guess this screwmount lens reveals some difference with LV and VF metering in manual..I can live with that!

When i get my k1 back from repair i will do some testing. I have 3 tak M42's including yours.

Not a Number · 02-02-2019, 11:01 AM - **1 Like**

Originally posted by DeanG

Thanks, well I shorted out the contacts and the camera thought I was at f/8!

The camera shouldn't show an f-stop but rather F- - unless the "A" pin is shorted out. The "A" pin on the body mount is recessed so you would have had to press the foil into the opening in order to do that. If it was shorted out you would be able to change the aperture setting with the eDial. The setting on the camera would have no relation to the setting on the aperture ring unless you set the ring to f8 as well.

If you didn't press some foil into the "A" pin opening then perhaps the "A" pin is shorting out on it's own. Does the viewfinder / LCD show a f-stop or F- - when the Takumar is mounted without the contacts shorted? Try cleaning the "A" pin.

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02-01-2019, 02:19 PM	#16
DeanG New Member Join Date: Jan 2019 Posts: 9 Original Poster	Very interesting, I can follow that. Thank you! I noticed about a 1 stop difference up to F/8, but at F/11 the exposure readings get closer. I seldom go smaller than F/8so I should be able to set exp comp and store it as a screwmount VF user mode and be good most of the time, or if I am working at a more leisurely pace, meter in live view. Interesting discussions.

02-02-2019, 03:22 AM	#17
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,219	Ok well it doesnt sound like the focus screen. I think you are just going to have to put it down to the defference between the two metering systems. At least with DSLR's we have the advantage of the histogram. I always have mine displayed in instant preview. You can then quickly make an adjustment to the exposure depending what the histogram is telling you.

02-02-2019, 05:04 AM	#18
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Try putting a bit of metal foil over the contacts. Hold it down with a bit of sticky tape before mounting the Takumar. Green button metering doesn't work on some bodies without an electrical contact on the mount. It shouldn't matter with screwmount but you never know. Does the imbalance change depending on the scene/target you are shooting? Try using a gray card as the target.

02-02-2019, 05:04 AM	#19
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Try putting a bit of metal foil over the contacts. Hold it down with a bit of sticky tape before mounting the Takumar. Green button metering doesn't work on some bodies without an electrical contact on the mount. It shouldn't matter with screwmount but you never know. Does the imbalance change depending on the scene/target you are shooting? Try using a gray card as the target.

02-02-2019, 09:19 AM	#20
DeanG New Member Join Date: Jan 2019 Posts: 9 Original Poster	Thanks, well I shorted out the contacts and the camera thought I was at f/8! Time to quit worrying about it and take some photos. Easy enough to dial in some exp comp, thanks everyone for the theories and help, but I guess this screwmount lens reveals some difference with LV and VF metering in manual..I can live with that!

02-02-2019, 10:41 AM	#21
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,219	Originally posted by DeanG Thanks, well I shorted out the contacts and the camera thought I was at f/8! Time to quit worrying about it and take some photos. Easy enough to dial in some exp comp, thanks everyone for the theories and help, but I guess this screwmount lens reveals some difference with LV and VF metering in manual..I can live with that! When i get my k1 back from repair i will do some testing. I have 3 tak M42's including yours.

02-02-2019, 11:01 AM - 1 Like	#22
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,526	Originally posted by DeanG Thanks, well I shorted out the contacts and the camera thought I was at f/8! The camera shouldn't show an f-stop but rather F- - unless the "A" pin is shorted out. The "A" pin on the body mount is recessed so you would have had to press the foil into the opening in order to do that. If it was shorted out you would be able to change the aperture setting with the eDial. The setting on the camera would have no relation to the setting on the aperture ring unless you set the ring to f8 as well. If you didn't press some foil into the "A" pin opening then perhaps the "A" pin is shorting out on it's own. Does the viewfinder / LCD show a f-stop or F- - when the Takumar is mounted without the contacts shorted? Try cleaning the "A" pin.