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Aaron Jones Sr. September 14th, 2014 01:14 PM

Electric Follow Focus
 
Has any tried this with there manual operations:

DSLR Lens Controller Electric Follow Focus Control For Baseplate

The one thing as i transition to manual i still want to zoom in and out with out the footage being unusable for the period of the zoom. I currently have the Tamron 17-50mm and when I try and zoom with it in a slow motion it gets a little jerky where there is not a smooth transition from one zoom frame to another. So I was looking for the electric follow focus kits as maybe a solution. Just wondering if any one else has had any experience with them?

Chris Harding September 14th, 2014 05:38 PM

Re: Electric Follow Focus
 
Hi Aaron

Powered focus will not help you there at all as all it does is allow you to turn a control as opposed to turning the lens barrel which is harder. Bear in mind that most zooms like we have are NOT parfocal so if you are in focus at 50mm you won't be in focus at 18mm optically but you depth of field might be sufficient to actually keep you in focus!! You have to understand depth of field first!!!

Use the online DOF calculator to work out what's in focus and what is not as follows.

Online Depth of Field Calculator

Let's say we are standing 20' from a wedding ceremony and we want to know what's in focus at both 18mm right thru to 50mm

With the lens wide open at F2.8 you are in focus from 10' right out to infinity ..great!! start zooming up to 50mm . Now zoom up to 25mm and you will see you are in focus between 13' and 42' Go right up to 50mm and you are now only in focus between 17' and 23' so the DOF gets tinier as you zoom.

Also as you stop down the lens the DOF increases. I can set my Tamron 10mm lens to a focus of 2.5' and then wander around and film and I will always be in focus as long as I don't go closer than 2'!!

If you need easier focussing then just get a standard follow focus unit which simply transfers the focus ring to a control knob on your camera .... Cine City have them. www.thecinecity.com

You can make life a lot easier too with a clip-on level to get to the lens easier and they work on the zoom ring too!!!

Chris

Aaron Jones Sr. September 14th, 2014 10:43 PM

Re: Electric Follow Focus
 
Hi Chris,

Thanks for the advice... I can find the follow focus all over the net but the Clip on level you mention i'm not familiar with. What exactly is that?

Chris Harding September 14th, 2014 11:52 PM

Re: Electric Follow Focus
 
Here we go

:::: Welcome to VARAVON ::::

Also try google and put in "DIY Follow Focus" There are tons of neat solutions out there!! I made my own with two "o" rings but I don't really want a rail under my camera even so doing it DIY is cheap!!

B&H have quite a few different manual system too!!

Do you HAVE to have a powered one??? It just seems an overkill and every time you change lenses you have to readjust the powered unit. With the levers it's quick and easy and you can have one of the zoom ring too!!

Some guys have used jar openers too and they seem to work well!!!

Time to get inventive????

Chris

Aaron Jones Sr. September 15th, 2014 02:25 AM

Re: Electric Follow Focus
 
I have two Sling Follow Focus levers on the way from Amazon... Thanks for the tip. Looking into the DIY Follow Focus now. I like DIY stuff and I have made a few things so far just because I like that sort of thing.

Chris Harding September 15th, 2014 05:09 PM

Re: Electric Follow Focus
 
If you maybe want to go one step further and not spend a lot of money then this might work well. It's pretty cheap so I don't know how good it is but I might even throw $50 at it and see how it works.??

Neewer Follow Focus CN 90F With Gear Ring Belt F DSLR Cameras Camcorders ES 13 | eBay

Chris

Aaron Jones Sr. September 15th, 2014 05:41 PM

Re: Electric Follow Focus
 
I definitely would like to try one of these. As i read the reviews on this i see that most reviewers say that it is like a cheap toy. But NEEWER makes more quality ones that get good reviews. Looking at this one it would seem that it makes noise and maybe hard to fine tune and dial in to that sweet spot. Just a observation looking at it. the groves in the gear look large and maybe move in larger increments instead of small smooth myopic ones.

Chris Harding September 15th, 2014 08:58 PM

Re: Electric Follow Focus
 
Hi Aaron

It you are patient then just hang in there ..I'll probably order one this week when the guy I sold my stock lens to, pays me. I'm not expecting a miracle at that price but who knows ..it might just work.

I'll let you know and keep you updated. I'll have to mod my current rail system too as to save weight I made it with 12.5mm tubing not the normal 15mm so the diameter and spacing might be out.

Chris

Chris Harding September 16th, 2014 05:28 AM

Re: Electric Follow Focus
 
Just ordered the "el-cheapo" follow focus so when it comes I'll stick it on the rail and see if it's worth using.

Your comments about gear pitch are quite valid Aaron!! There must be a bit of play between the teeth so we will see how bad they actually are!!

I also saw a follow focus that uses a continuous belt ... that might interest you? I would say the there would be no "slack" to mess up your focus so that might work better??

You also get the friction ones that have no play but they are mostly DIY jobs. The idea is to mount a skateboard wheel on a bracket and have it at 45 degrees to the lens focus ring. As you turn the wheel it turns the lens ring purely by friction ... the brackets might be awkward to make though!!

Will keep you posted.

Chris

Aaron Jones Sr. September 16th, 2014 02:32 PM

Re: Electric Follow Focus
 
Awesome, i look forward to your findings... Just as a note i do have some roller blade wheels i bought last year looking to make a DIY dolly mod for my tripod and on PVC rails. I never got around to making it but still have the wheels.

Currently I'm looking to find a descent rail base right now to start from. Kind of hard to decide. Kind of taking my time to find at the right price.

Chris Harding September 16th, 2014 05:34 PM

Re: Electric Follow Focus
 
Hi Aaron

I have a Camtree rail system .. I think it was $110 from India and has the usual 15mm rails plus a camera mount and a tripod mount ... It looks smart but the camera mount doesn't lock as well as I would like it too.

It all depends on whether you need to be able to switch the camera from handheld to tripod? I don't as I have two cameras so the rail is on my B-Camera which is either handheld or on Stedicam.

Just make sure your rails themselves are long enough!! Check the distance from the camera tripod hole right up to the front of your longest lens. My Sigma 18-35 is quite lengthy and the focus ring is quite a distance up front so make sure the rails will actually get there if you are going to put a follow focus there.

My follow focus seller here says he has shipped so that means it will get here in 6 days from today.

Chris

Steve Bobilin September 16th, 2014 08:29 PM

Re: Electric Follow Focus
 
Quote:

Originally Posted by Aaron Jones Sr. (Post 1861710)
Just as a note i do have some roller blade wheels i bought last year looking to make a DIY dolly mod for my tripod and on PVC rails. I never got around to making it but still have the wheels.

Here is a really good DIY video I based my dolly on.

Aaron Jones Sr. September 16th, 2014 08:57 PM

Re: Electric Follow Focus
 
Chris that is a very nice video for a dolly. I really like the fact that he has cross members that connects with both sides of the rails together. i did think of doing that and nor did the video i seen have that done. It looks neater and purposely done. I think i have found a Rod base i want to try out HERE I would have to buy the rods separate but I can get them the length i want them to be. The only thing I do not like about this base is the adjustment on the rod holders. They only have one screw holding each side and I'm not sure if i like that or not. Either way i can get it where i like it and just drill and tap permanent screws to fix them in place.


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