[geekette]

--does this make sense?

Doesn't the K-X and K-5 have fixed aperture for video? i.e. wide open on K mount lenses? With the M42 lens I can at least close it up a bit to allow for more depth of field so the person I am videoing has a little room to move around.

[luftfluss]

The level of exposure control available when shooting video with current SLRs varies widely. Many cameras -- especially those aimed at consumer use -- still opt to keep things simple with fully automatic exposure control. Manual exposure control is also now a reasonably common option, though, especially in prosumer and professional models. Like its predecessor, the Pentax K-5 offers somewhere in between these extremes, giving you a choice of either automatic or aperture-priority exposure modes. In Auto aperture mode, the camera adjusts the aperture as needed, but just like the K-7, doesn't report the current value on the LCD screen. (We'd still like to see Pentax change this behavior to allow aperture display regardless of exposure mode, at the videographer's option.) In aperture priority mode -- referred to in the menu system as Fixed Movie Aperture Control -- the current aperture is displayed in the lower left corner of the LCD screen, and can be changed by rotating the rear command dial. You can't adjust it during recording, but whatever value you set before you begin your clip is the one the camera will use. This is a great feature that gives a fair degree of creative control over the look of videos, although it doesn't go as far as some cameras in allowing direct control over shutter speed or aperture.

Pentax K-5 Camera Video - Full Review

I wonder how the K-5's video recording would work with a lens like the Helios 44-2, which has the 2 aperture rings, the most forward one allowing you to smoothly adjust aperture on the fly.

[geekette]

I just used my Helios 44-2 on my K-X in video mode. You just adjust the aperture to f16 then open/close up the aperture to your liking with the secondary stop down aperture adjustor. You can see the depth of field and lighting change on the fly. Like when it's wide open it's really bright... i close it up to f4 then it gets darker then the camera compensates for it and adjusts the light up (I guess with dynamic ISO or whatever). When you get to a certain point it just gets too dark and the camera can't compensate for it being that closed up--This is indoors with ambient lighting.

I am going to go try it outdoors now with it closed all the way to f16.

[geekette]

Just tried it outdoors! it works great! Same lighting at f2 vs f16.. the camera adjusts the lighting--and the depth of field increases dramatically

I just also tried it with my 18-55 DAL.. Although there is an aperture adjustment when in video mode it seems to be locked on a fixed non adjustable aperture setting--unlike my manual helios 44-2!

It seems useful to be able to film at f16 outdoors since the pentax cameras do not have video autofocus.

[luftfluss]

Glad it works well! I have the K-x & Helios, but I've never shot video.

I'd imagine you'd be able to do some real cool cinematography with that combo.

[MDegri]

Just tried it on a K-5 with a Pentacon 30mm f/3.5 M42 lens (with continuous aperture). It works! lighting adjusts up to f16. Will be fun to try it out properly.
Thanks for the tip!

[hoanpham]

m42 mount was preferred by canon users when shoting video. There was no AF in video earlier, normally cheaper lenses, and in some cases, better lenses and/or better suited lenses.

[Clavius]

I did some video at night yesterday with my new Porst 55 ƒ1.2. It's PK, but I've removed the aperture lever to make it work in AV mode. It's awesome!

[altopiet]

Any of the old manual Pentax mount lenses should work, you just have to remove the aperture lever, and to prevent the clicking noise when you adjust aperture while recording, the ball under the aperture ring.