Lens moves during focus pull. Any suggestions?

V

VillageBoi

Active member
No idea if anyone here has tried using the following lenses with a follow focus -

Canon 18-55mm f3.5-5.6 - The stock lens that came with my 450D
Tamron 70-300mm f4-5.6 - Also bought with my 450D

I've use both lenses extensively for stills - had to learn with some form of glass :embarasse.

At the end of last year I bought a 7D and today my Proaim follow focus V2 with Rail system arrived. A very solid bit of kit, however, I have just noticed that 'starts' and 'stops' when pulling focus with the Proaim the image moves all over the place. At first I thought it was the proaim then I 'tried' and found out that the 2 lenses basically are crap! (That really answers my questions)

Held them in my hand and found out that they easily jiggle about - or shall I say have some 'play' in them. The 70-300 is worse. Lenses have Play???? Huh! Is it normal for the mentioned lenses to do that? I know, I know I do have to invest in 'proper' glass. Just thought I could use them until I can afford better lenses.

I also can't try my other cheapo - canon 50mm 1.8 as none of the lens gears can be fitted onto its odd focusing ring shape. It does not have any of the play the other lenses have.

Don't get me wrong, I have never needed to film with the 18-55 or the 70-300 yet (as I only use the 50mm 1.8 which is a zillion times better as per lowlight) but having a new toy and them being the only lenses that 'lens gears' fit on I have to ask if anyone does use them for focus pulls and if so... how? as I wouldn't mind using them for now during daylight.

Thanks in advance for any suggestions.
 
What you are describing is just one of the problems that is faced when you use a still lens in a cine situation. This is why cinema lenses cost so much more than still lenses.

A cinema lens will
- hold focus while you zoom
- maintain exposure while you zoom
- have minimal breathing characteristics for rack focus shots
- have little play or wiggle as you describe
- have a better focus throw
- have hard stops on the focus ring and proper markings

everything we are doing with DSLR's and still lenses is a hack so you just got to figure a way,
hunt down the best still lenses (usually primes), and ditch the equipment that isn't working for you
 
I've tried a bunch of Canon lenses and no "play" when using at good ff system like the cinefocus. Cheaper lenses are usually a poor choice when it comes to shoot motion video.
 
It's not play- that's called breathing. That will happen to some extent in any still lens. i.e. one that is not optimized for motion picture cinematography. Makes sense too- why should the maker of the lens care about how the lens looks while being focused in the middle of a shot. Because when taking stills only you'd never see that effect.

Noah
 
Noah, he's not talking about breathing. I have the same thing on my work 17-40 L lens. Basically the first moment of turning the focus ring results in a shift of the whole image up or down, as if the lens element is loose inside. This lens though, was abused and I always accredited this fault to a drop or two (I'm not the only user).
 
I'd love to see a shot- it really depends... I've seen horrific breathing on some still lenses...

Noah
 
Hey guys, thank you so much for your responses.

@ J Davis - Yes I know I really should use 'cinema' lenses to avoid all these issues but... yikes £££££! Maybe someday. Never say never. Having said that, gonna take your advice and ditch the crap lenses asap.

@ editman - I'd sure like the Arri FF I saw at BVE, London a few weeks ago. The Proaim is still good and the issue is the actual lenses themselves, went up the road and tried a friends lens - it was 'perfect'. Next thing for me to do is upgrade lenses. Thanks.

@ NoahK - It's not breathing in this case. The lenses are such crap that... how do I explain... the part of the lens with the focus ring actually moves... jiggles about IN the body of the same lens - if that makes any sense?? Kinda like a tube that fits into another tube but not flush enough to be stable so any pressure makes the front bit of the lens move around. Forgive my crap terminology in the post and replies.

@ Voytech - thanks, that's what I meant.

@ NoahK (again) - Actually from initial tests these 2 crap lenses don't really breath that bad. If at all I use them I just wont even try pulling focus. If I record a test I'll let you know where to find it.

My initial 50mm 1.8 test is - http://vimeo.com/8000672

Bit by bit I will upgrade most of the stuff I have but for now I don't think it's wrong to use what I have to get lots of practice. I just wanna go out there and shoot. And I hope y'all don't get mad when I say I also bought the coollcd.com 200 buck 7" HDish monitor.
I'm from a village and had to sell half a herd of goats to buy that s**t! lol

Thanks for taking the time to respond guys.
 
hey none of us can afford cine zooms, we all in the same boat, I've had a lot of luck with primes
when it comes to zooms I rent EOS 17-55, 24-70 or 24-105 and even then i use it more like a variable prime just to save time switching.

If u have the money check out zeiss primes in particular c/y mount or zf mount. They are the probably closest thing you'll get to cine.
 
J Davis said:
If u have the money check out zeiss primes in particular c/y mount or zf mount. They are the probably closest thing you'll get to cine.
Click to expand...

No idea what c/y mounts are. Will google after post. I know of zf's but heard ze's are the way to go..? Still boils down to 'if' I had the money right now :happy:

Shooting a film with my rig early next month and we are renting lenses.

Forgot to add - thinking of getting Nikon primes for starters like the 50mm 1.4 AI - just whatever I can lay my hands on, bank manager already wants me dead!
 
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Also worth checking out Leica R glass. Have a look at Ffords in Inverness, got my 21 Super Angulon and 180 Apo-Telyte from them. Both have long focus throws, the 21mm is something like 330 deg, the 180 about 300.
Dave
 
daveswan said:
Also worth checking out Leica R glass. Have a look at Ffords in Inverness, got my 21 Super Angulon and 180 Apo-Telyte from them. Both have long focus throws, the 21mm is something like 330 deg, the 180 about 300.
Dave
Click to expand...

Thanks Dave, just checked their online shop as I was 'curious' - yup, the one Leica R lens I saw was over £4500.00 - well outta my league for now.
 
yokotas13 said:
buy L lenses, you wont have this problem!
Click to expand...

L lenses aren't a "fix everything" solution. If you bothered to read the thread, post #5 states that the same issue is present in a 17-40 "El" lens.

I'm really getting tired of "buy L lenses, it will make everything better" posts. Especially when they don't contain any content whatsoever. Its almost as bad as the f/1.2 recommendations in "my first lens" threads.
 
say what you want, I have NO problems with ANY of my Ls.

i say buy L lenses becuase they are superior in pretty much every aspect than a non L. Thats why i dumped all my mediocre lenses and switched to Ls a few years ago. big investment, yes. but build quality is much better.
 
shaocaholica said:
L lenses aren't a "fix everything" solution. If you bothered to read the thread, post #5 states that the same issue is present in a 17-40 "El" lens.
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I do know 'L' lenses are not a 'fix everything' solution and I did read post 5, however, I do appreciate the input you guys are giving and will not dismiss suggestions that I asked for. I will, however, collate all this information and continue my own research.

Some L's will work and some won't!. Sorry someone made you buy or almost buy a 1.2 that, maybe, didn't work for you.
 
yokotas13 said:
say what you want, I have NO problems with ANY of my Ls.

i say buy L lenses becuase they are superior in pretty much every aspect than a non L. Thats why i dumped all my mediocre lenses and switched to Ls a few years ago. big investment, yes. but build quality is much better.
Click to expand...

I am looking at so many different lenses for filming - L's, the tokina 11-16, Tamron 17-50 2.8 vc, Samyang 1.4's - starter lenses until I can afford s**t hot ground sand :happy:
 
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