[andy271]

Hi guys hope someone can help Ive been using a manual focus lenscalled the Zeiss 35mm f2 zk mount which I purchased off a chap onhere Ive been using it hand held and normally only do tripod shootingbut decided I wanted to try hand held photography anyhow I am usingback focus the af button but when the green hexagon focuses I stillhave to press the shutter button even though I hold the af button isthis because its a mf lens
Also does the greenhexagon have to be still for a couple of seconds then press theshutter button

[stevebrot]

Are you trying to do catch-in focus? The AF button does not act as a shutter release. Make sure catch-in focus is enabled (c4 menu) and the camera is in AF-S mode with AF/MF switch in the AF position. Hold the shutter button down and use manual focus. The shutter will release when focus is attained.


Steve

[andy271]

hi steve no i just want to use back focus button af to take the shot ...here is a video i watched so was hoping pentax was the same

You Tube

You Tube

[stevebrot]

Added:

If you are just trying to use manual focus confirmation (green hexagon) using the AF system, set the AF/MF switch to MF. Half press of the shutter will turn on the AF system to enable the green hexagon, unless the AF/AE-L button is configured to AF2. In that case, press the AF/AE-L button to enable the hexagon.


Steve

[pschlute]

Hi guys hope someone can help Ive been using a manual focus lenscalled the Zeiss 35mm f2 zk mount which I purchased off a chap onhere Ive been using it hand held and normally only do tripod shootingbut decided I wanted to try hand held photography anyhow I am usingback focus the af button but when the green hexagon focuses I stillhave to press the shutter button even though I hold the af button isthis because its a mf lens
Also does the greenhexagon have to be still for a couple of seconds then press theshutter button

Back-button AF does just that....auto focusses. To take the shot you use the shutter release button.

[stevebrot]

hi steve no i just want to use back focus button af to take the shot

The video is using an auto-focus lens. Just to be clear, your Zeiss ZK 35/2 is a manual focus lens and does not do AF. See note above to enable green hexagon when set up for exclusive back button focus (AF2).


Steve

[pschlute]

hi steve no i just want to use back focus button af to take the shot ...here is a video i watched so was hoping pentax was the same

Pentax is exactly the same. In that video he focusses with the AF back button and takes the shot with the shutter button.

---------- Post added 04-09-21 at 07:48 PM ----------

Just to be clear, your Zeiss 35/2 is a manual focus lens and does not do AF.

Only just realised he is using a MF lens. He needs to use the shutter button to take the picture, same as every other camera on the planet. Back button does not operate the shutter

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Last edited by pschlute; 04-09-2021 at 12:26 PM.

[andy271]

Thanks guys i understand now my mind has been all over the place asive been struggling with the Zeiss lens in another post I went outtoday and used the af button to confirm focus wait until the greenlight stays solid then press the shutter button and have got muchmore sharp shots
For some reason theZeiss is all over the place with exposure but I think if I use thegreen button on the k-1 im hoping that will get the correct exposure
and on another notewhen I try to af fine tune the lens the charts I have are a little tosmall to observe what is sharp and what isn’t i.e. front and backfocus it isn’t a problem with a 50mm but 35 is fairly difficult tosee the chart even zoomed in I don’t know what im going to do itsdriving me crazy

[stevebrot]

For some reason theZeiss is all over the place with exposure but I think if I use thegreen button on the k-1 im hoping that will get the correct exposure

Put the aperture ring in the "A" position.

and on another notewhen I try to af fine tune the lens the charts I have are a little tosmall to observe what is sharp

The best advice I can give is to quit trying. You cannot do AF fine tune for a manual focus lens, even for focus confirmation using the green hexagon. Your ZK lens does not provide an ID to the camera to pair with the adjustment number. There is a workaround using a global (all lenses) correction and saved USER modes, but that is a whole 'nother discussion.


Steve

[andy271]

Ive don’t the tests Steve with my chart but its a bit awkward as i want to be 5.5 feet away and the chart is small Ive done the apply all with the Zeiss lens if the exposure is off it doesn’t create that Zeiss micro contrast but if your exposure is good i can see its there i wont give up until all my testing is done and if the Pentax struggles in live view with exposure i may just sell up i love the Pentax camera and Pentax and the users are great and helpful so this is a last resort but im getting frustrated with the system

[One3rdEV]

Hey Andy- I watched the video:

As previously stated by others, the video is using auto focus type lenses and pressing the rear focus button is activating the lens motors to find focus. After reframing the image (change in camera angle) the shutter button is then pressed to actually take the picture. Towards the end of the video in the night scene he uses the same technique and refers to it as manual focusing to avoid focus hunting. His reference to manual focusing once again actually means he wants his focus point fixed and to not change when he reframes the picture which could lead to focus hunting which he demonstrates (note that he is still using an autofocus lens, because a true manual lens would be incapable of being camera driven and consequently hunting).

Note that when using rear focus button with a Pentax camera and an autofocus lens:
- Rear button focus must be activated in the menu.
- Shutter half-press focus should be deactivated in the menu (otherwise the process of pressing the shutter button to take the picture will typically change focus to the reframed point the sensor is seeing).

Still regarding the video you were referencing:

If a manual focus lens were used then rotating the lens focus ring while pressing the rear focus button until the green hexagon illuminates to indicate that focus is obtained. Then the rear focus button no longer needs to be pressed and the shutter release button must be pressed to take the picture.

No comment regarding the use of rear button focusing and tracking such as in the soccer examples. I have never experimented using the rear button focusing on sports other than in a focus once and reframe perspective.

Now regarding use of a Manual Focus Lens:

I would highly recommend you experiment using both of the techniques that Stevebrot mentioned. You may likely find at least one of these to be beneficial.

Apparently my previous comments are very elementary and way behind the conversation.

For AF Fine point adjustment with the 35mm lens you may need to abandon using a small target technique and try a different technique. Search for alternative strategies here at the forums. Also after finding the right global setting then keep in mind his suggest of assigning it to a user mode.

[andy271]

hanks one3rdev i kept my finger on the rear focus then pressed the shutter i will remember i don’t need to keep my finger on it
Yes af fine tune not easy with 35mm lens
Ill keep trying i goto the same spot everyday so i have a reference and will carry on idid get better results today hand held with the af button method and making sure the green hexagon is still
The problem i came across was Zeiss was overexposing the image so i may try the green button on the k-1 and see if it makes a difference

[Transit]

Are you in the "A" position on the lens dial ?
metering mode ? spot, centre weighted etc ?

[andy271]

Hi transit yes its on the lens multi segment and spot

[Transit]

cool. Is the aperture control working from camera ?

---------- Post added 10th Apr 2021 at 11:35 AM ----------

Ive don’t the tests Steve with my chart but its a bit awkward as i want to be 5.5 feet away and the chart is small Ive done the apply all with the Zeiss lens if the exposure is off it doesn’t create that Zeiss micro contrast but if your exposure is good i can see its there i wont give up until all my testing is done and if the Pentax struggles in live view with exposure i may just sell up i love the Pentax camera and Pentax and the users are great and helpful so this is a last resort but im getting frustrated with the system

there can be influence of light coming in through the optical viewfinder when in lv
they used to include a wee cover to blank it out, dunno if they still do

keep at it you'll get it sorted