March 02, 2015, 04:03:05 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Topics - Videoshooter

Pages: [1]
Lenses / Misbehaving Aperture on 24-105L
« on: March 08, 2014, 11:01:42 PM »
Hi All,

Just wanted to check if anybody has experienced the below problem before. I purchased the lens 2nd hand but the seller denies any knowledge of the problem (yeah, right!). I suspect a trip to Canon is in order for this lens but thought I'd run it by everyone here first in case there is some simple solution I've overlooked like shaking it vigorously or perhaps performing a rain dance.

My 24-105 f/4L is having problems with the aperture behaving erratically. When the camera is set to any aperture other than f/4, the iris will constantly change between several different settings. When zooming in, it gets darker (ie the lens doesn't compensate by widening the iris at longer focal lengths as it should to maintain the same aperture ratio. I'm not talking about a flicker, I'm talking about an obvious ~2-stop darkening of the image through the viewfinder) but when zooming out again it stays dark still.

The aperture setting in the camera is not reflective of what the lens iris is actually set to. Eg: the camera might read f/4 while the lens is actually at f/22. Changing the aperture does sometimes cause the iris to adjust, but only within the range of the camera - ie: if the camera reads f/5.6 but the lens is actually at f/22, I can only open up by one stop, because even though the lens is now only at f/16, the camera now thinks it is at it's limit of f/4 and so will not adjust it any further.

And as a precursor to all the usual generic responses, so far I've tried the following: same lens on multiple cameras, different lenses on same cameras, every combination of IS/AF on/off, cleaning the contacts on both the lens and cameras, camera powered by a fully-charged battery, in M mode, live view/movie mode and regular stills, and played around with the DOF preview button. Curiously, the DOF preview does not do anything but when using live-view AF via a half shutter press it does open the iris up to brighten the image, but only temporarlily. And yes, it is definitely the iris and not the shutterspeed/ISO messing up because a) it's in M mode with nothing on auto, and b) because I can see the iris blades flickering erratically through the front of the lens.

Thanks in advance for any help you can give me.... even if that help might be to tell me where my nearest Canon repair centre is!

Video & Movie / Webisodes for short film
« on: November 26, 2012, 02:59:12 AM »
I've been working on a short documentary and a lot of the leftover footage is being put into a series of webisodes - check them out and let me know what you think so far:

Lenses / Canon 17-55 f/2.8 IS vs 24-105 f/4L IS
« on: August 23, 2012, 10:30:15 AM »
Hi all,

I've just upgraded to the Canon 5DmkII and sold my 550D. I'm still keeping my 60D which will now go from being my A-camera to my B-camera. I've still got some budget to spend on lenses to shoot video, and was originally planning on getting a 17-55 f/2.8 IS to replace my Tamron 17-50 f/2.8. My main reason for upgrading is to get IS. Now I'm leaning towards keeping the 17-50 and adding a Canon 24-105, for the extra reach (espescially on the 60D) and the fact that it can be used on both cameras (and any future Canon cameras). I'm not interested in the 24-70 I or II due to (a) the price; and (b) no IS.

What I'd like to know is what real-life effect it will have on the quality of my videos. Everything I've read suggests the high ISO performance of the mkII gives a 1-stop advantage over the APS-C cameras; does this mean that shooting with the f/4 on the 5dmkII will give similar IQ to shooting with f/2.8 on the 60D, if all else is equal? Can I push the ISO of the 5dmkII further than on the 60D to compentate for the 1-stop aperture loss?

EOS Bodies - For Video / Which cheap telezoom for video?
« on: July 22, 2012, 08:57:03 AM »
A slightly different question to the regular onslaught of "Which L-series lens should I trade my wife for?"...

I'll be going on a trip later in the year where I might be bringing my girlfriend along with me as a 2nd shooter and assistant. I'll be working on some surfing web-clips for various websites and magazines, and am planning to have my girlfiend shoot a 2nd angle of the action. What I'll need for her is a lens that is light, and has relatively good IQ (though I understand the constraints of budget tele-zooms and am not expecting miracles - just something that will cut together with my Sigma 150-500mm without instantly being noticeable). I'll basically pre-set the focus for her, and set the camera to auto-ISO (blashpemy, I know!) so all she needs to do is hit record and pan. So MF ring quality is not an issue - nor is any other build quality seeing as the lens will pretty much be thrown away after the trip. Things that are an issue are weight, size and price.

The lens will be used only outdoors in daylight, and I'll leave the aperture at about f/8-11 in order to increase the DOF and put the lens into it's sweet spot.

So basically what I'm looking for is the best optics possible in the budget 70-300mm range, regardless of all other factors such as build quality, AF speed, USM, etc.

IS is also a consideration - with a big question being whether or not any of these lenses have an IS tripod mode that can handle pans well. The lens will always be used on a fairly decent tripod (manfrotto 502HD head) but again, my girlfriend is not a trained camera operator and will need any help she can get.

With all that in mind, can anybody recommend any particular brand/lens?

Thanks in advance!

Pages: [1]