Olympus 14-35, 35-100 zoom lens owners

monkeyking

monkeyking

Well-known member
Try this simple test on your AF100:

Turn on camera, set lens to manual iris and set F stop to any stop except wide open. Slowly zoom lens back and forth from wide to tight and vice versa.
Listen carefully . Do you hear a tiny click as you rotate the lens? Watch the LCD screen or EVF while zooming. Do you see the F stop value change a tiny bit when you hear that click? Do you see the image get a little brighter or a little darker when you hear that click?
If you do , the lens is not maintaining the set F stop throughtout the zoom. The tiny click is the sound of the iris changing when it should be silent and constant.
I observe this iris glitch using both of my lenses , both Panasonic & Olympus lens adapters, both AF100 & GH1 cameras. On the GH1 camera, the glitch is observable in video as well as still modes.
AF100 and lenses have current version firmware but my guess is that Olympus must issue a firmware update to address this issue.
Share your test results here.

chris
 
I don't have the lens' but I don't think your going to get a firmware update out of olympus to 'fix' the issue. While the len' is f2 throughout it's zoom range, it's a complicated lens and is designed for still photos. i don't think it's high on olympus' priority to get it to work well for video unfortunately.

Since they don't hold focus while zooming anyways, are you really going to zoom while recording?
 
monkeyking said:
Try this simple test on your AF100:

If you do , the lens is not maintaining the set F stop throughtout the zoom. The tiny click is the sound of the iris changing when it should be silent and constant.
Click to expand...

If the F stop is constant, but the focal length changes, the iris cannot be constant. For a longer focal length you need a wider aperture to retain the the same F stop. F stop is a ratio of focal length to aperture.
 
These are the lenses mentioned a lot as the run and gun ones for people with a broadcast camera background getting into the AF100, right?
 
The iris glitch occurs only when using F stops Other than F2. No issue shooting wide open - stays at F2 all the way.
 
I hear the clicks as well, but it is only a big problem if you are stopping through several f-stops in a quick zoom or pan.
 
It seams theses lenses together with the AF does click once everytime you go through the zoom range in either direction. When opening up iris it also for a brief moment tells you it's F1.8! Seams to be a clitch of some sort. After F7 or so it seams to go away also. My GH1 behaves almost the same but it even clicks on F2.0 but after F4.0 it seams to not change on the 14-35.
 
Thanks for the confirmation and other observations Editman. I guess we'll be hearing from others here soon enough.
 
editman said:
It seams theses lenses together with the AF does click once everytime you go through the zoom range in either direction. When opening up iris it also for a brief moment tells you it's F1.8! Seams to be a clitch of some sort. After F7 or so it seams to go away also. My GH1 behaves almost the same but it even clicks on F2.0 but after F4.0 it seams to not change on the 14-35.
Click to expand...
That's interesting. I frequent dpreview forums quite a bit, and it seems that many fourthird lens' are actually brighter than they operate at. For example, many think the 7-14 is closer to f/2.8, but electronically is limited to f4. by disconnecting the communication (slightly loosening the lens), the iris opens up even more.

Back to this topic. Since the f2 zooms are so complex (some say overengineered) in the way the lens' groups shift around (this lens is super sharp btw!), I could imagine that somewhere in the zoom range, it could actually be brighter than f/2, maybe just as it transitions a movement.

Just a theory.
 
It's probably not surprising that the lenses don't work smoothly when stopped down while zooming because they weren't designed to work that way. As Joesiv pointed out, the problem is that they are DSLR lenses. On a DSLR the lens always stays at the widest aperture setting as you compose/zoom/focus. It's not until you press the shutter release button (or DOF preview button) that the aperture actually stops down to the desired aperture. I wouldn't expect Olympus to fix this issue.
 
More annoying than the click when changing aperture is the visual shift in aperture you see if you try to shoot in auto iris. I did some testing for the first time today with the lens and it is not made for auto iris. Not that it gets used much but I thought I'd give it a try.
 
joesiv said:
That's interesting. I frequent dpreview forums quite a bit, and it seems that many fourthird lens' are actually brighter than they operate at. For example, many think the 7-14 is closer to f/2.8, but electronically is limited to f4. by disconnecting the communication (slightly loosening the lens), the iris opens up even more.
Click to expand...

Are those users sure that they're not just allowing some light to bleed in, like when freelensing?

I'm wanting to use the AF as both a studio camera supplemented with a couple of GH2s, and also as a run-n-gun. I've used the HVX for run-n-gun for the past few years, and I'm very comfortable using it like that. My style of shooting involves 24p Cine-D gamma, cinelike matrix, all manual zoom/WB/iris/shutter degree/focus (except I highly rely on the auto-focus button sometimes to pull the focus real quick as I move. I've used tripods, but I actually got really comfortable with stabilizing the camera pressed just below my shoulder. I'm worried about using the AF w/ 14-140 for run-n-gun not because I like auto focus or servo-zoom, but because I'm worried about (1) the focus not pulling fast and accurate with the push button auto-focus like on the HVX, especially with the larger sensor/shallower DOF, and (2) because I'm worried that the size and weight of the camera won't allow for adequate stabilization, and won't mesh with my style of pressing the camera against my lower shoulder like the butt of a rifle.
 
Besides the clicking, how do you guys like shooting with the 35-100? I have the 14-35, and I am looking for something in the higher range of 50-85. Looks like this might fit the bill pretty good. Any other options out there that I don't know about?

Edit: Started new thread with question
 
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