FX1 iris controls... not a happy customer

[Tom Hardwick]

Very true Serena, but back in the 70s Super-8 camera manufacturers such as Canon and Nikon were making 10x zooms with an f/1.4 maximum aperture that held throughout the zoom range. That's half a stop wider than the popular f/1.6 of today.

And all this while feeding a 'chip' (the Super-8 frame) that was almost exactly the same size as a current 1"/2.7 chip - just a tiny fraction smaller than a 1"/2 chip. Lots of us look on the half inch chip as a biggie.

tom.

[Serena Steuart]

Tom, I don't recall 10x f/1.4 zooms on S8, and would have thought that max apertures were more like f/2.0 and f/2.8. However I don't have any of the old literature to check! I remember being surprised to find that zooms for still cameras couldn't hold max aperture during the zoom, and somewhat disappointed when moving to video that the same thing was present there. http://www.visualproducts.com/store0...&Cat=8&Cat2=20

[Tom Hardwick]

My 1974 Canon 1014E had a 10x f/1,4 zoom (see? It's in the name) as did the Nikon R10. The sound on film 1014XL-S had the same. They're shown here:

http://super8guy.com/

tom.

[Serena Steuart]

Ah, well. Yet another reason to keep using film!

[Kevin Shaw]

Originally Posted by David Payne

Am i right in saying if i push either the iris, gain or shutter button i get the numerical value on the screen and this therefore means manual mode is activated...?

Not exactly: it only means you've manually locked the setting for whichever button you pushed. If you want a full manual exposure on an FX1 you have to push all three buttons for iris, shutter *and* gain, then set each of those to the values you want as indicated on the LCD or viewfinder. Otherwise the items you haven't locked will continue to auto-adjust, resulting in an incorrect exposure for strongly backlit subjects.

If you want to be able to quickly switch back and forth from auto to manual exposure on the FX1, lock any two of the three exposure items and switch the third on and off auto as needed. For example, lock the gain and shutter but leave the iris on auto until you need a manual exposure, then lock the iris and set it as needed. There is no single exposure-lock button on the FX1 like there is on some other video cameras (e.g. Canon GL1/GL2, Sony A1U, etc.).

[David J. Payne]

hmm thanks all for your advice..

i had another chance to play around with the camera this weekend. I found that occasionally when shooting in manual mode in a dark environment i can set manual iris to as open as possible, set shutter to 50 and leave gain how it is as i am put off by the picture noise i have gotten in the past by using gain on different cameras. Anyway, in this manual mode as far as I know the camera is set up to let as much light in as possible but occasionally when i flick back to auto lock, it gets brighter. How can this be? Is it something to do with the picture profile setting as I havent really ever bothered changing these.. I have always left it on PP3...

[Tom Hardwick]

You sure you've got that right - you flick back to auto lock and the recorded image gets brighter? I simply cannot see how this would happen, as in auto it will bump to max gain (+18dB) and widest aperture for the focal length in use. You're still on the default shutter speed, right?

tom.

[Douglas Spotted Eagle]

You've answered your own question. Picture profiles *usually* are set up to affect gamma, color. Clearly, your PP3 is reducing available light. Turn it off.

[Kevin Shaw]

Originally Posted by David Payne

Anyway, in this manual mode as far as I know the camera is set up to let as much light in as possible but occasionally when i flick back to auto lock, it gets brighter. How can this be?

When you switch back to auto mode that allows the gain to go back to maximum, which will make your picture brighter unless you had gain at the full +18db in manual mode. And as DSE said, make sure your camera settings aren't limiting the maximum gain amount - there's a setting which does exactly that for those who want auto-exposure with gain limited to some specific value.

[David J. Payne]

thanks again guys.. i should have worked out that the gain was boosting up in manual mode. Seems silly that it would do this outside in very very bright light tho? Do you know what I turn off in the specific picture profile to stop it limiting available light? I didnt know you could turn the PP off totally.. i thought you had to have one selected..

All things considered, I have just purchased a 2nd FX1 so once I work out how to use the light settings effectively I'm sure i'll be very happy.

[Tom Hardwick]

You certainly don't have to have any PP selected. They all move the image away from the default setting, which you may find perfectly acceptable.

[David J. Payne]

great.. so in theory with PP off, shutter set to 50 or 60, gain to +18 and iris as low as possible I should get the image as light as possible, is that correct? I will have another play around tonight but I think this issue should be solved now. Thanks a lot.

[Tom Hardwick]

That's sort of correct. Of course you can slow the shutter speed as well to get greater exposure of the chips, but you'll get subject and camera movement recorded as a blur. For static shots of a building at night, say, I often use 1/3 sec and f/5.6, and have the gain at zero.

tom.

[Boyd Ostroff]

Creating a picture profile with everything at the default EXCEPT turning on black stretch will help a little in dark places. But be sure you haven't selected either of the cinematone settings, you will lose as much as a full stop from them.

[Jim Michael]

Originally Posted by Tom Hardwick

That's sort of correct. Of course you can slow the shutter speed as well to get greater exposure of the chips, but you'll get subject and camera movement recorded as a blur. For static shots of a building at night, say, I often use 1/3 sec and f/5.6, and have the gain at zero.

tom.

How can your shutter speed be slower than your frame rate?