[adwb]

Hi guys, is it possible with a M series lens to use the meter in a K5 to get the correct exposure?

I have been given a a tokina 135 mm lens to try but it not only does not seem to meter thus requiring a hand meter but also the aperture no mater what its set to seems to stay wide open at f2.8 the iris works as does the lever on the lens to open and close but it dose not seem to stop down if set to f8 or f16 or whatever .

I have the setting in the menu C 4:.27 set to using so the shutter works an in P mode it seems to meter ok but because the aperture it is not changing essentially it is useless

i'm sure on my K10 that I no longer have a manul lens worked ok

[Adam]

Here are the instructions: https://www.pentaxforums.com/forums/54-pentax-lens-articles/110657-how-use-me...k-x-k-7-a.html

[adwb]

Thanks Adam I also just remembered to press the green button in manual mode just before you posted thanks again.

[marcusBMG]

I've been writing up some info on this

Using manual focus lenses on Pentax (and Samsung)DSLR's

I would be parrticularly interested to hear how your exposures work out with M42 lenses in Av mode, and any other point you learn pertinent to a K5 (like with an anodised/painted mount lens...)

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Last edited by marcusBMG; 01-21-2014 at 10:07 AM.

[Lowell Goudge]

I've been writing up some info on this

Using manual focus lenses on Pentax (and Samsung)DSLR's

I would be parrticularly interested to hear how your exposures work out with M42 lenses in Av mode, and any other point you learn pertinent to a K5 (like with an anodised/painted mount lens...)

You should add something on metering accuracy and how to measure it.

I have done quite a bit using the cameras I own to assess the metering accuracy of MF lenses on pentax cameras

[adwb]

first the lens I have is a k mount I believe the M42 are screw mounts and behave differently.

so being a k mount in AV mode the lens stays wide open [f2.8] and the expose obtained automatically is fine and accurate

the exposure selected in centre metering is consistent through all stops but in spot mode there is a tendency to over expose from f11 to f16

this tested on a tripod aiming at a blue clear sky with light cloud patches and is not only visible obvious but you can see the histogram start to shift to the right slightly between 5.6 and 11 and between 11 and 22 it becomes very obvious

Marcus with regard to you post you gave the link to, my only comment is the font you have selected makes trading hard especially on smaller screens like ipads.
.

[marcusBMG]

Marcus with regard to you post you gave the link to, my only comment is the font you have selected makes trading hard especially on smaller screens like ipads.

Thanks for pointing that out BION i dont have an ipad to check ...
Font is a cursive one from the google selection... Font too small, or lacks clarity or both?? Does my adaptall page look better?
http://www.tremyfoel.co.uk/photography/Adaptall/TamronAdaptallInfo.html

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Last edited by marcusBMG; 01-22-2014 at 11:09 AM. Reason: adaptall page link

[stevebrot]

I've been writing up some info on this

Using manual focus lenses on Pentax (and Samsung)DSLR's

I would be parrticularly interested to hear how your exposures work out with M42 lenses in Av mode, and any other point you learn pertinent to a K5 (like with an anodised/painted mount lens...)

You should clarify that what you have termed the "Takumar pin" is actually only found on SMC and S-M-C Takumars where it is used to support open-aperture metering on bodies that also support that feature.


Steve

[marcusBMG]

You should clarify that what you have termed the "Takumar pin" is actually only found on SMC and S-M-C Takumars where it is used to support open-aperture metering on bodies that also support that feature.


Steve

OK thanks for that Steve.

May I suggest you guys PM me since this is digressing from the OP's subject

[adwb]

Thanks for pointing that out BION i dont have an ipad to check ...
Font is a cursive one from the google selection... Font too small, or lacks clarity or both?? Does my adaptall page look better?
Information page on Tamron adaptall, adaptall-2 system and lenses

it is a bit small and like all cursive script it look pretty but makes on any screen hard reading, you are better served using Tahoma or any of the screen friendly ones.

[adwb]

OK thanks for that Steve.

May I suggest you guys PM me since this is digressing from the OP's subject

don't mind it was a daft post any way if i engaged brain I would have remembered green button and manual and never posted

[marcusBMG]

How do you like trebuchet?

Using manual focus lenses on Pentax (and Samsung)DSLR's

[adwb]

Much better

[marcusBMG]

Much better

Great

[arkav]

Thanks Adam I also just remembered to press the green button in manual mode just before you posted thanks again.

I believe you can also meter using the DOF preview position of the on/off switch of the K5. ( doesn't work on K-30 )