Holy crap Sgpro FF 5mm - 7mm play

yea but hes torquing the gear......

if theres somuch resisitance from the focus ring on the lens, its set up wrong...... it should move smoothly....
 
I think thats the way they tested all of the FF and the redrock only has 1-2mm , chroziel .5-1mm, petroff 1-1.5mm. He stressed that the gears used in the sgpro are all plastic. I am so disappointed after watching the test, as I was about ready to buy the sgpro FF.

Why not the Redrock FF then? The entire section of redrock port is glued onto the knob itself. With time, and the use of whip and crank, it will come loose and the entire "insert" will just fall off. Yes it did happened to my ex redrock FF as well as other ppl's redrock FF.
 
There are several parts of travel in a FF system our test is designed to uncover both points of weakness. One is any play in the knob before the gearing kicks in and transfers the energy to the internal gearing. the second failure point is the internal gearing itself. This test test the potential failure of both points and the potential for your marking on the lens to walk. Keep in mind that when working with any FF unit the absolute most effective use is to make your markings on the lens itself. Look for us to test Zacutos new FF system coming up as well.

PS
Matt said the gearing "felt" as though it was plastic. We didn't pull the gearing apart to verify that, so I just want to make sure that is clarified.
 
The gear that meshes with the lens gear is a very light weight aluminum. I agree it does look plastic, and I thought the same but it is not.

The gearbox inside the SGff is a standard, off the shelf item, which I happen to have previously used for other projects.

Il just go and cut one open and see whats inside it....
 
we were referencing the internal gearing not the lens gear. But hey cut that baby open if you want, love to see the internals :)
 
Upon first inspection the gears looked metalic, but having blasted the grease off with compressed air, they are some kind of plastic. They are sttill in the casing, all I did was drill a little peepy hole in the case. its very hard plastic, i cant shave it or scratch it with scalpel but it is plastic. Probably some kind of resiny stuff.

Ive never had a problem though, my SGff gets about 1-1.5mm play...

It was likely he didnt adjust it properly, theres a collar under the knob to adjust the backlash.

Just for referance the knob on the FF is incredbile quality, it is plastic (but so is a £2000 arri one), the disk that the knob is bolted to is machined aluminium, but the knob itself is injection moulded plastic, and its very solid. no mould split or sprue marks, its very well made, no complaints there at all.
 
I have since identified the gear material to be acetal homopolymer. Another gearbox is available from the same manufacturer with exactly the same external dimensions with steel internal gears.
 
I have to agree - I had my new SGpro delivered within 24hrs of Freshdv posting the review. At first I thought they must have a broken unit - no way I get anything like the play on the review.

I would remove the knob + disk etc and check the setting of the collar as hoarp mentioned above. Also check to see if the small screws that hold the gear and the knob are tight against the 'flat' part of the shaft. (though as you mention in the review that the gears turn in sync with the knob I don't think its that)

Can someone correct me here if I am wrong - but the RR uses the same gearbox? (or at least the metal version)

I am very happy with the SGPro - its build quality is great and I measure the play at approx 2mm.
 
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I have to admit that I was a little surprized as well, when seeing the review. I don't have any experience with this FF myself, but I've followed its development a bit online. I seem to recall that Wayne used the same gearbox as the RR FF but with a slight modification. It's been selling for quite a while (6 months?) now and when it was released I don't remember reading (reviews/user feedback) about it having that much play.

Cheers


PS: Kandal, not to criticize FreshDV as I appreciate what you guys are trying to do over there, but the SGpro FF review could have been a little bit more 'in-depth', like the other ones you did last year.
 
First, I should thank Wayne at Shoot35 for offering a follow focus unit in addition to an SGPro adapter for our testing blitz some time ago. He has been cooperative and most gracious in providing gear and we at FreshDV greatly appreciate it.

Regarding the questions posed in this thread about our SGfollow focus review. No, we did not make any adjustments to the SGfollow focus other than what you would do to properly mate any follow focus to a lens. Admittedly, it's been months since we shot that segment, but I do not recall any directions in the box when the unit arrive for testing either (correct me if I'm wrong, Kendal). Nor can I find any notes about backlash/adjustement sent to me via e-mail. Had there been directions as such, Kendal and I would have adjusted the unit. So if we've erred there, this is the first I am hearing about it.

A few comments:
1. We have been 100% up front and clear about our testing methodology for follow focus units. The other follow focus video reviews have been publicly available for nearly a year now. There is zero ambiguity about what we will do when testing the units. If you were shipping a follow focus to FreshDV for testing, wouldn't you first ensure it was a reliable and well-adjusted unit? I know I would. That being said, we have no reason to believe our test unit was a faulty or maladjusted follow focus.

2. Wayne at Shoot35 was the first to know when I posted the video review...we generally send a courtesy e-mail to the manufacturer of any product that we review. I have not heard back with any sort of criticism or questions, and as such I still have had no reason to believe we tested the unit improperly.

3. When conducting our gear "play" test, we simply hold the lens still and apply a little torque on the focus knob. It's not rocket science. We don't overtorque the gear any more than a stiff cine/PL zoom lens would on a cold day. Sure, maybe you are using smooth, loose still image lenses (many are), but we don't know that. FreshDV cannot account for individual user variables, we can only hold everyone up to the highest standard of professional gear, in this case the analogue to a large, stiff cine lens. In short, I do not believe our torque test is unfair, nor do I feel we've mis-tested the unit in question.​

I'm CC'ing this thread to Wayne at Shoot35 (in case he hasn't seen it) and would be happy to answer any questions or concerns either via e-mail privately or here on this forum. Thanks for all the feedback.
 
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We appreciate the input here and would like to thank Matt and Kendal at FreshDV for taking their time to test the SGfollow focus.

Our modification to the gearbox reduces 'backlash' between the internal gears to virtually nothing, what you are seeing in the FreshDV review is 'flex' in the system which is quite different and as Matt mentioned would only be a problem if you have a really sticky lens.

We are indeed using the delrin geared version of the huco gearbox, we are going to test the steel geared version to see if this reduces the amount of flex.
 
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