Continuos / Smooth aperture ring

[James Donnelly]

I could post this question in a more generic forum, but I think there are some pros hanging around in here so I'll just stay where I'm familiar.

I have seen reports of people modifying their lenses so that the aperture ring no longer clicks by taking out a ball bearing.

My question is, from a cinematography point of view, what type of shot requires a change of aperture while rolling?

[Joel Peregrine]

Hi James,

Originally Posted by James Donnelly

I could post this question in a more generic forum, but I think there are some pros hanging around in here so I'll just stay where I'm familiar.

I have seen reports of people modifying their lenses so that the aperture ring no longer clicks by taking out a ball bearing.

My question is, from a cinematography point of view, what type of shot requires a change of aperture while rolling?

Any shot where the camera is moving and the lighting conditions change, like going inside to outside or even between rooms with different light levels. More important obviously if you're on a steadicam and you want the iris changes to be smooth so you can use the shot.

[Ted Ramasola]

when lightings change , like moving in and out of a building. I would prefer putting the camera on AUTO ISO (something the traditional video camera can't do). this is more smoother and realistic as DOF would change when you adjust iris, unless this is your intention.

Having discovered this, I decided not to remove the ball bearings that makes the click on manual aperture lenses.

These DSLRs are really changing we look at and solve things.

[Sam Kanter]

>>when lightings change , like moving in and out of a building. I would prefer putting the camera on AUTO ISO (something the traditional video camera can't do). this is more smoother and realistic as DOF would change when you adjust iris, unless this is your intention.

Having discovered this, I decided not to remove the ball bearings that makes the click on manual aperture lenses.

These DSLRs are really changing we look at and solve things. <<

Why is there no option, on this BB, to quote the last message posted???

Getting back to subject - I agree that auto ISO works quite well and quickly for video if light changes. Definitely the way to go for some situations.

[George Angeludis]

This is very useful info Sam. About the ISO.

[James Donnelly]

Originally Posted by Sam Kanter

Why is there no option, on this BB, to quote the last message posted???

I noticed that too Sam. I get around it by hitting the little multi-quote button, then reply. Seems to do the trick.

Thanks for all the replies. Yes the auto ISO is a powerful feature I didn't at first appreciate. It brings the manual mode to life for stills. It's great that you can set a maximum too. For me, 'M' is the new 'AV', as I can control my DOF, and fix the shutter speed at 1/f to avoid shake, while letting the auto ISO correct the exposure.

Given the new light shed by the above posters, I can also see certain situations where smooth aperture would be preferable for video, for instance if you wanted to cap the ISO at level where it wouldn't have the latitude to do the shot without noise/dynamic range problems. I can also see that sometimes auto ISO and smooth aperture would work great together, say if you wanted to limit the DOF change.

After thought: Ted, since ISO is adjusted in 'stops' (as in doubling/halving light sensitivity) by the camera, isn't it the case that relying on auto ISO for a shot will cause the exposure to jump and cause a noticable stepping of perceived exposure?

I have lens I need to take apart to clean, and I'm pretty sure it will be minus one ball bearing soon.

[Joel Peregrine]

This is another really useful tool - acts like a smooth iris for when its very bright and 100 or 200 iso isn't enough to bring the light levels down:

Loving the Fader ND and Singh Ray Vari ND. Life savers in New Delhi! | Philip Bloom

This isn't the brand I have but it looks similar:

Fader ND Filter ( ND2 to ND400) 77mm Neutral Density - eBay (item 170472249803 end time May-12-10 12:31:51 PDT)

[Ted Ramasola]

Originally Posted by James Donnelly

After thought: Ted, since ISO is adjusted in 'stops' (as in doubling/halving light sensitivity) by the camera, isn't it the case that relying on auto ISO for a shot will cause the exposure to jump and cause a noticable stepping of perceived exposure?

I have lens I need to take apart to clean, and I'm pretty sure it will be minus one ball bearing soon.

I didnt notice it to jump. Its like "smooth transition" feature in some video cameras. I had a shot where I panned from a view outside a window to the interior of the room. It was an average speed pan. And it seemed smooth.

[John Wiley]

I just bought an old 200mm m42 lens to put on my GH1 and - a nice surprise - it has no aperture clicks, just one smooth transition! Very nice feature and I wish all lenses you do this! It's even better than on my FX7 which has very obvious steps when adjusting the iris.

[James Donnelly]

Which lens is that?