How to shoot video on Pentax K-1 with manually self choosen aperture?

[RobvanO]

I'm looking for an instruction how to shoot video, using variable aperture.
Is there a way to shoot video with manually variable self-choosen aperture?

I want to shoot video using an old prime K-lens (SMC PENTAX-M 28mm 1:2,8). I want to choose the aperture by hand during shooting in video-mode. The lens has only an aperture ring, but in video-mode, also with f:16 the aperture seems to be constantly wide open.

The only way in which it seems possible to shoot video with variable aperture is using an old M42 screw mount lens, using a Pentax M42 screw mount adapter, in the manual mode (automatic / manual switch), .
Is there another way, so that I can also use the older M- and F-lenses (K-bajonet) and use the aperture during shooting video?

Sorry if I overlooked a thread with the answer, but I couldn´t find it untill now,,,,

 

[MightyMike]

I'm looking for an instruction how to shoot video, using variable aperture.
Is there a way to shoot video with manually variable self-choosen aperture?

I want to shoot video using an old prime K-lens (SMC PENTAX-M 28mm 1:2,8). I want to choose the aperture by hand during shooting in video-mode. The lens has only an aperture ring, but in video-mode, also with f:16 the aperture seems to be constantly wide open.

The only way in which it seems possible to shoot video with variable aperture is using an old M42 screw mount lens, using a Pentax M42 screw mount adapter, in the manual mode (automatic / manual switch), .
Is there another way, so that I can also use the older M- and F-lenses (K-bajonet) and use the aperture during shooting video?

Sorry if I overlooked a thread with the answer, but I couldn´t find it untill now,,,,

Looks like you have an issue with M-series and K-series lenses, the camera is setup to keep them wide open and only stop them down just before the exposure or you could use the green button in manual mode to get a stopped down meter reading but this is all only for single shot work. for video you have but 2 options 1) buy an A-series or newer equivalent lens, I have one for sale on the Pentax forums marketplace right now or 2) Something I don't recommend at all but you could cut off the aperture lever (or remove it surgically by opening the lens) and the lens become much like an M42 lens in that the only aperture control will be the aperture ring video or stills. Anyhow the SMC Pentax-A 28mm F2.8 is available if you want it.

 

[RobvanO]

Hello MightyMike,

Thanks for your reply, but it's not the answer I hoped for.
I hoped there would be a setting somewhere in the menu that would activate the stop-down of the aperture lever so that I can change the aperture while shooting video.
And I don't want to apply surgical interventions on my lenses.
Having read your reaction, the only way to do what I want seems to continue using old M42-lenses in manual mode.
Or has anyone else other reactions?

And in reaction on your offer, I have all the glass I need.

 

[KPM2]

Hello RobvanO

I tried video with my SMC M 50 mm f1.7 and my K1:

first let me say that I did nearly never a video with it my K5 and the K1 is new to me.

Therefore it can be that you must mean an other thing with your question....because it do work with my lens:

1.) I set the camera to TAv = I can select the aperture at the lens and the shutter speed at a wheel. I can see when I use the DOF switch how the histogramm look at my chosen aperture and when I close the aperture too much I can see that the camera start to be unable to find the right ISO for to adjust the exposure and the histogramm 'runs' to the left.

Without using the DOF-switch I can set the aperture how I will, the camera let the lens full open....but of course, it close it always during the video recording. That mean you can during the video recording also change your aperture and the camera try to find another ISO for the get the exposure right, or when your pan and the scene get brighter, the camera do change the ISO for to match the right exposure. This happens slowly. I tried also in the second video menu the point keep the highlights....it looks like the camera match than a little quicker the exposure, so that during a pan you get not so quick overexposed scenes, when they are brighter than the scene before.

2.) Av mode: it show no shutter speed, so that the K1 use now the shutter speed and ISO for to match the exposure. Using the DOF-switch like above.

3.) M mode: do not match the exposure when you change the aperture during the video. It stay on the setting you got via the green button metering you did bevor you start the video. It also did not help to push the green button again during the video record.

4.) Maybe you need a big Auto ISO range, for that the camera can find always the right ISO for to match the exposure.

5.) BTW: You can hear this 'klick...klick' in the audio, when you change the aperture of the M 50mm, so maybe a extern mico is a good idea.

6.) it would be nice if we would get the ISO displayed. Than we could know what ISO the camera just use....and if it use already the min or max possible ISO, so that we could know that we should not open or close the lens more than.

7.) You can use in the TAv, Av mode the AE-L button too: Than you fix the setting the camera use and the camera stops to match the exposure automatically. On that way you can control at once by yourself the exposure via changing the shutter speed or aperture.

best regards KPM2

 

[Wanganuibloke]

wow great reply !

makes me want to declick a lens and try video

 

[KPM2]

Hello again RobvanO

I wrote that maybe a extern micro could help to eliminate the sound of the aperture 'click' in the audio.....I tried it out with my extern micro and...no chance, you still hear it very well :-(

BTW: I tried the Movie SR and noticed, that when I pan, objects like a table do lost there form....they get stretched and compressed. Not sure if that will be very noticeable elswere. The Movie SR works otherwise not bad...compared to the handshake I see in the movie when I use my K1 without the Movie SR. But I have to say that I have not steady hands :-( .

BTW: it would be nice when a Fn button had a setting for Movie SR ON/OFF...than I could press the button to switch the Movie SR OFF before I start to pan...like I can do this on my video camera, than those strange stretch and compress - look would not happens during a pan.

- I had my 3-wheel at selecting the crop and I could change during the record between the FF and crop mode... nice when the prime lens do have not the right focal length for some situation.

Now I have a question to you: do you know if the AA-simulation do works in the video mode too ?

All in all, because I do no videos with a DSLR, my quick made test indoor video with the K1 did impressed me do to the low noise look it has ....wow !

best regards KPM2