I have a k5iis, and am hoping for a bit of advice on the AF Fine adjustment for different lenses. I've read the manual, but I'm a bit unclear how it works.

I've previously set adjustments for a DA55-300 and a DA18-135 using the adjust one setting, and that's been ok. I now want to add an adjustment for an old manual lens I've bought off Ebay (Cosina 100mm macro). I understand that this lens isn't recognised by the camera so I need to use the "adjust all" option. My question is whether when I set this, will it affect the other lenses with "adjust one" settings? The manual states:

"Even when an adjustment value has been saved using [Apply One], if you press the OK button with [Apply All] selected in Step 3, the [Apply All] value
is used instead of the [Apply One] value."

My DA55-300 is set to +6. If my cosina needs -4 (it may not, I haven't tested it yet), would that mean I need to leave the 55-300 at +6, change it to +10, or will the "adjust one" setting be completely ignored anyway?

Thanks in advance for any advice.

Lens arrived yesterday, well packed and in good condition. Hopefully I'll get to try it out tomorrow.

Many Thanks

Hi,

I'm interested in the 18-135. I've pm'ed you.

Sigma 18-250 lens arrived today. Well packed and in perfect condition. Many thanks.

PM sent the 18=250.

I'll try again. Your lens is F2.8 wide open, but your camera thinks it's f1.2 due to some issue with the contacts on the teleconverter.
When you alter the aperture via the camera, it doesn't actually tell the lens the aperture it wants. What it tells it is how many stops from the maximum to reduce by. Therefore, if your camera thinks it's F1.2 wide open, and you tell it you want f2.8, it is actually telling the lens how many steps to reduce by.
I realise I assumed f1.2-2.8 was 4 steps (1.2-1.4-1.7-2-2.8 ), and you may have more available options than that, but the principal is the same. You are telling the lens to reduce x steps from the maximum aperture, not to go to a specific aperture value.
Therefore, if your camera says f1.2, and the lens is actually f2.8, then when you reduce to f2.8 on the camera, the lens will have reduced the same number of steps to a higher f value. (I think I was wrong about f11, and it is actually closer to f6.7). That explains the different dof between the f1.2 and f2.8 exif shots. They are actually at f2.8 and something closer to f6.7.

The way Iunderstand it is that the lens transmits the info on largest aperture and number of stops to smallest. In this case, incorrectly f1.2. When you set aperture to f2.8 on the camera you are actually telling the lens to decrease aperture by 4 stops, so although the exif says f2.8 (f1.2 + 4 stops) you are actually shooting at f11 (f2.8 + 4 stops).

It shouldn't be anything to worry about. Does tha camera recognise the lens properly without the teleconverter? If so I guess its something to do with the contacts between the lens and the converter.
I think the only issue might be a problem with exposure, dependng on what mode you use. Manual and green button should be ok, but I think that some other modes might get it wrong if they are calculating for a stopped down lens.
I'm no expert though, so I could possibly be talking complete rubbish.
Maybe everything will work but your exif data will show a very expensive, rare lens.
Your photos certainly look ok.

It looks as if the lens electrical contacts have somehow all been shorted. If you look here: http://www.bdimitrov.de/kmp/technology/K-mount/Ka.html there is a table that shows the combination of contacts for each aperture range. If all of them are shorted then the camera will think it has a f1.2-f22 lens fitted.

Has this now sold?
If not, I'd like it for my daughter, who is doing her art GCSE, and seems to be using my camera more than I am at the moment.