Follow Focus - Gear Lash

C

Christopher Barry

Veteran
1. I understand that RedRock improved their Follow Focus with Rev 3, as per this FreshDV review. The gear lash is said to have gone down from 4mm to 5mm (Rev 2), to about 1.5mm to 2.0mm of gear lash with Rev 3.

2. The next FF I am considering is a Cavision. Can anyone advise what, if any, gear lash exists, or perhaps someone who has used both can provide a comparative comment/opinion?

3. Cavision, what whips (connection) does it take? Can you use the RedRock whips?

4. Cavision, how do you adjust the arm tilt? Is it spring loaded or screw adjustment or does that lever on the barrel release the arm, you adjust and then position the lever back to lock down the arm position?

Thanks.
 
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Hi Christopher:

1. Adam C (Taormina on DVX User) has the Cavision FF and loves it. I have not asked him specifically about this issue but you can. He has lots of posts on the 35mm adapter board.

2. Have you read the new issue of DV Magazine? They have a review of five FF units and rated the Red Rock very highly. They did also test the Petroff recommended by Jim as well. http://www.dv.com/reviews/reviews_item.php?articleId=196603447

I am going for the Red Rock because a single sided FF is fine for my needs (the Cavision is available in single side or dual side but costs considerably more than the Red Rock).

It's tough to chose, they all look good for the $$. But stack on all of the other toys I need for my HVX and I have to go economical.

Best,

Dan
 
Hey guys we tried to get a Cavision to review but the wouldn't let us have a unit. I will say for the money the RedRock (Rev 3) was easliy the best value for the money. Comparing very closely with the Chrosziel and other high end units. I will say I have a Cavision Matte Box and in general am not overly excited about Cavisions product line. By the end of next week we will have extensive video reviews posted on FreshDV.com showcasing all of the testing we put each unit through and showcasing the function and design of every unit. Along the same lines you guys might be interested in our 3 Part series on the art of pulling focus:

http://www.freshdv.com/tutorials/


Part 3 will go up sometime tomorrow. Feedback always welcomed to help keep it Fresh!!!
 
Christopher Barry said:
2. The next FF I am considering is a Cavision. Can anyone advise what, if any, gear lash exists, or perhaps someone who has used both can provide a comparative comment/opinion?

3. Cavision, what whips (connection) does it take? Can you use the RedRock whips?

4. Cavision, how do you adjust the arm tilt? Is it spring loaded or screw adjustment or does that lever on the barrel release the arm, you adjust and then position the lever back to lock down the arm position?

Thanks.
Click to expand...

The cavision FF has no perceptible lash whatsoever. Maybe it's hard to believe, but the unit feels like it has metal to metal gears inside (it doesn't) - there is no play at all. The unit is made of all metal minus the gears. It can be easily upgraded to a double wheel FF if you need that capability. Can't say enough about it.

I actually don't know what whips it takes. Obviously it has a connector for them - I haven't had a need to use them yet but will look soon. I don't think redrock's whips are long enough anyways. what's the point of having the AC that's 8-10" away?

I use two adjustments on the FF. Firstly, one lever on the rails to adjust it fore or aft on th rail. Single lever, no binding, smooth operation. Some of my lenses are long enough to require this movement.

The second adjustment is a single lever, non-spring loaded that controls the arm. you can actually move the arm through an arc of about 90 degrees to get the right position. It works well in any position. You have to understand when I change lenses, I adjust the arm almost every time as the barrel diameters are slightly different. It works very well.

Hope that helps,

Adam
 
The thing that gets me about the redrock is this: (warning - I have an offensive opinion.)...When the first units came out, they had an ungodly amount of lash. I didn't experience this, I just read about it. It was still enough to make me think that these guys released that POS before all the bugs were worked out of it, and permanently soured it for me. Now all is well, I suppose. But I'd never buy one, even though I own and am happy with my other redrock stuff.

That may seem harsh, but considering a poor 1st AC can ruin your movie, or a really great 1st AC with a shitty follow focus like a redrock version 1 can ruin your movie, it's a serious topic.

Here I'm shooting with a lens like my 50mm 1.2, when set at wide open has a DOF so critical that if the talent farts he'll be out of focus, and we're dealing with lash on the FF!!!!!

Not on my set.

end rant.
 
I'll tell you this much we shot our part three of pulling focus tutorial with Bob Sanchez a first AC with a sterling reputation here in Chicago he has done alot of the features that come in to town. We shot with an 85mm Zeiss wide open and he pulled flawlessly at the end I asked his professional opnion on the unit and he liked it alot said their was no issues at all on his end, and the price really surprised him. I think RR learned their lesson about pushing a product to market before its ready but it this case rev 3 isn't even the same unit really. To leave a company no room to improve and fix a product doesn't make much sense to me.
 
Jim, Petroff and Chroziel, I hear both are great products in that price range. Thanks for the suggestion to consider.

Dan, I always appreciate reading your view on A/V matters. RedRock and Cavision came to mind, as cost effective and possibly reasonable quality, although there are many different views, experiences and expectations out there. Redrock does seem like exceptional value.

Kendal, what can I say, FreshDV has provided me with so much great information over the last year, after I found you guys on the net. The cool thing about your reviews is that you often show me more than a photo of a product (often from one angle also - limiting). Viewing a lot of new products is not always possible here in Australia. The remaining 1.5mm to 2.0mm back lash now in RedRock FF, seems to read as acceptable, after the view expressed by Bob Sanchez (part 1 & 2 interview, interesting and educational!) Red Rock FF is still an option for me to consider. Thanks for the follow up info Kendal.

Adam, you were the first person who came to mind for positive feedback on the Cavision FF, also Eric of Overland Films comes to mind. Can no perceptible lash be measured in millimeters? I like the adjustable rotating arm feature, as I already have a wired servo motor FF unit, which is spring loaded, and this allows me to position different parts of the lens, which I find does make a difference, depending on the lens. The plastic gears kind of concerns me for longevity and a stiff lens might not be good for it in the long run. My lenses mostly have Arri gears (mod 0.8) so I would need to replace the base Cavision unit Fujinon or Canon gear with a Cine gear(s). I like the fact you can buy 28mm to 44mm (4 in total) Cine replacements gears to use on different lens diameters and rotation requirements for sensitivity and accuracy. What I would like to know is how do you change the gears? Is it a slide on and off situation, or do you screw on and off the gear? Screws/wear and tear concerns me.

Both the RedRock FF and Cavision FF still interest me. A few more answers and I will take the plunge on one. :dankk2:guys!
 
FWIW, I'm on an Arri dual FF and full Preston wireless system right now which is pretty plush - okay... it's beyond sexy. About $20k of sexy to be exact.

The Cavision single and dual unit compares favorably to the Arri FF from a performance standpoint. The Cavision unit is well-manufactured and features no discernable backlash. If other manufacturers tell you backlash is acceptable in any degree, they are selling a defective product. There is no room for backlash on a follow-focus. At all.

:)

The wheels and marking disks are appropriately sized and the unit is substantial.

That said, there are differences in materials (not a deal-breaker), finish and tolerances (very minor, as the Cavision is a relatively simple unit).

The Arri unit has ingenious configuration options, with multiple diameter / offsets mounting built into the single iris rods crossbar. When I discuss Cavision's products with customers, I compare them directly to competitor products that mainstream productions use. When I sell their matteboxes, I will always tell customers that the Cavision units are getting better with each new generation and that we use them on our own 1/3" form-factor cameras and that we have never had a customer return one - ever.

They're not a MB20 or a Chrosziel, but they are more than functional and beyond affordable by comparison.

e
 
Christopher Barry said:
Adam, you were the first person who came to mind for positive feedback on the Cavision FF, also Eric of Overland Films comes to mind. Can no perceptible lash be measured in millimeters? I like the adjustable rotating arm feature, as I already have a wired servo motor FF unit, which is spring loaded, and this allows me to position different parts of the lens, which I find does make a difference, depending on the lens. The plastic gears kind of concerns me for longevity and a stiff lens might not be good for it in the long run. My lenses mostly have Arri gears (mod 0.8) so I would need to replace the base Cavision unit Fujinon or Canon gear with a Cine gear(s). I like the fact you can buy 28mm to 44mm (4 in total) Cine replacements gears to use on different lens diameters and rotation requirements for sensitivity and accuracy. What I would like to know is how do you change the gears? Is it a slide on and off situation, or do you screw on and off the gear? Screws/wear and tear concerns me.

!
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I simply cannot measure any lash - don't know what else to say. The thing is, I'm just not that religious about this FF - it's simply very good and no frills. As far as the plastic gear goes, I'm not sure if metal will be better. I recently swapped mine out for a mod .8 gear since my redrock rings were geared that way. Swapping it is a function of sliding it onto a tapered shaft, and securing with one screw. It can actually be mounted on either side of the arm - the shaft is tapered and tapped both ends. If it took 10 seconds to change the gear I'd be surprised. Not sure how you could really wear the gear out. Even if you do, it's 19 bucks.

I have one very stiff lens, a 135mm Nikon and it seems to cope just fine.
 
Christopher Barry said:
Can no perceptible lash be measured in millimeters?
Click to expand...
Having measured the lash on the 5 units in our DV Mag review, I personally would say that "no perceptible lash" probably equals 1-2mm of play in the system. I feel I'm being conservative in that statement. By our measurements, the Chrosizel, Petroff, and Redrock (current rev gearbox) all fall within that performance benchmark.

No budget limitations? The Chrosziel is oh-so-sweet and extremely well engineered.
Some budget concerns? The Petroff is a very viable Chrosziel alternative, built rock solid.
For rock bottom bang for buck and ROI, my money is on the Redrock.

FYI, we've posted the Follow Focus Tutorial Part 3 (behind the scenes!), and will also share DV Mag review footage on the 5 units tested, by no later than tomorrow at our Reviews index.
 
Erik (sorry about the spelling in last post), Arri and Preston is primo gear. I looked at the Preston website and on-line videos some time ago, when discussion was happening on the REDuser forum. I drool for that setup, but beyond my real needs, of course. I will replace my existing wired servo FF with the RedRock wireless when it is released in due course. Thanks for the confirming feedback on the Cavision FF.

Adam, thanks again for giving me a run down on your observation of the Cavision FF. I think I was perhaps misinterpreting that the gear box of the Cavision FF was plastic. I understand the gear that drives the gear of the lens is plastic, however, can you or Erik confirm what material makes up the gear box and guts of the Cavision, ie, is it plastic or metal? I can live with plastic replaceable gears that drive my lenses. And thanks for confirming the attachment method. It sounds solid. I was concerned that a screw alone held the gear in place, not a combo of tapered shaft and locking screw. Regarding a whip for the Cavision, this different FF model Cavision photo shows a more side view, revealing what appears to be a standard whip attachment, such as the RedRock option.
 
Hi Matt. Thank you for that clarification. If all units you mention feel basically the same, then that is a good note for me to consider. The one thing I do like about the RedRock gear is, if I buy the FF, the wireless FF and Matte Box (the later two when released), there should be no issue with all the pieces working together, all attached at once. No doubt, RedRock is the most cost effective option. Thinking cap time.... cheers.
 
Christopher Barry said:
The one thing I do like about the RedRock gear is, if I buy the FF, the wireless FF and Matte Box (the later two when released), there should be no issue with all the pieces working together, all attached at once.
Click to expand...
True, but I wouldn't be concerned that either the Petroff or Chrosziel would be non-standard or not work with the forthcoming RR Remote and Matte Box. And I've seen enough images and information on the new Redrock gear to be confident they are being designed with compatibility and configurability in mind. Bottom line...choose the ff unit that meets your needs, I don't feel you'll run into a problem with compatibility on the above noted units. Best of luck in your search!
 
Hi Kendal:

Nice job and thanks for your hard work on these. A few suggestions from a fellow reviewer?

1. Need to state MSRP at beginning of clip
2. A little information about the manufacturer and who they are and what they do would be helpful

Keep up the good work.

Dan
 
I used the RR follow focus on many run and gun shoots using a 50mm nikon lens and at times a 105mm lens on the M2. usually wide open with very shallow DOF. It has no lash issues for me or any assists I have worked with.

Now the indiefocus I tried to use on my feature CRUSHED was a nightmare that slipped and had so much backlash that you could not have more than two marks as the pre-loading of the handle was too much to compensate for. We tossed it after one day of horrorible experience and a few too many botched takes. We pulled focus right off the lens for the rest of the shoot. A pain in the arse but at least is was accurate.

I was very skeptical about the RedRock FF after that cheap FF experience. I was shocked at how good the FF worked and continues to work. It was as good as the FF I rented from MPS only lighter. And for the price. 100% happy. Low cost isn't a deal if it cost you more in production costs.
 
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