Cheap Chinese MB

Vitaliy_Kiselev

As far as I know none of currently sold such MB have filter problems.
Also 4x4 filters are not 100x100 filters, they are slightly larger. Larger trays are not for 4x5 filters also.

Vitaliy_Kiselev

It is now present in the rigs deal as part of complete rig.

We'll have it presented separately in MB deals soon.

Tam

I have one of these matte boxes. The filter trays definitely have issues with using 4x5.65 glass (4mm thick filters). The trays are plastic and do not grip the filter properly, meaning they will fall out easily. THe 4x4 adapter plates which are meant to fit 4x4 (100mmx100mm) filters do not work very well either - sliding from side to side when the tray is rotated. I suspect this would be a problem regardless of the filter type. After I talked to shop about this they have amended their site to say that the trays work with filters less than 3mm thick. I am in discussions with them about a re-designed filter tray, but nothing as yet.

vicharris

I've had one of these for 8 months or so from Redstar and it's held up pretty well. I used it on a few productions and one tough FOX promo and the only thing that happened was one of the filter trays broke when I dropped it. They are VERY fragile but what can you expect at $250. The trays are off centered as one reviewer said but I've used 4x5.65 glass so far and not seen any problems with wide angles and I've used the extra wide convertor on my old HVX200 and had no problems. I can see where one would have a problem with the 4x4's for sure. So far it's not a bad purchase and it sure blocks out a lot of light.

Roberto

@vicharris

Thanks for the advice. Mine arrived a few days ago and I'm giving it dry runs indoors with all my lenses. I'd appreciate any links to good-value 4x.65 filters (ND, gradient, etc). Also, it's nice to see the matte box's lower hinged bar is there, ready to screw-in a bottom flag. Is a 4th flag available as an option? Are filter tray replacements available? [Edit: I notice Red Star can be contacted re parts; I got mine as a grab-it deal and forgot who sells them].

One thing do I see as a compulsory modification: the inner hood is unacceptably reflective. Its surface should really be etched to a matte black and if necessary coated with black flock photographic paint. I'll probably just scuff the surface with coarse steel wool or emery.

Roberto

Good news for LA7200 Owners - This mattebox will allow the anamorphic adapter to fit in, from the front, using the largest rubber donut at the rear to exclude light.

And there's still room at the front for one filter! (Inserting the second, [rear] filter slider makes the LA7200 too tight a fit - but could possibly be machined)

Roberto

Step 2: Modding MB so as to insert LA7200 from the rear.

OK so I'm satisfied the LA7200 works with the mattebox. (FYI, the Panasonic 14mm pancake + LA7200 has to be moved forward past the front filter holder in order to avoid being slightly cropped at the sides. Any lens longer than that should work from further back).

Still, I am not prepared to spend that hour setting it up again and again. I'm quite happy to file 4 small notches so as to enable easy insertion from the back, rear adjustment to enable the 2-filters option, full use of the swing-away mechanism and after all, it's my mattebox and I'll try if I want to... [edit] OK, done. Success!

vicharris

@roberto

I haven't contacted Redstar about parts but it seems you've found that answer. Good deal! As far as good deals on 4x5.65 glass, I just ordered mine from B&H. I've tried Ebay to get good deals but by the time the damn auction ends, the price is 80-90% of the original! So I say just buy it new and not risk any defects. I'm actually looking into Lightworks Vari ND instead of buying multiple glass for the mattebox but the reviews seem to be all over the place with those type of NDs.

The one thing I still am not a fan of with this MB is when it's closed, it doesn't lock in place. If you tilt down the MB rotates out a half inch or so, pulling away from the lens. I can't image it with two filters in. Do you have the same problem and I'm not sure if this occurs with all swing away MBs.

Roberto

@vicharris

Tell us how the Vari ND goes.

Re swing-away play: it sounds like either your spring locking-pin (blue knob) has either developed play due to use (ie oval-shaped recessed hole instead of original round) or else it never entered the hole in the first place. If it has suffered that much wear already, then all us owners should watch out: make sure the lock-pin has really clicked back home before use - and maybe even start using an elastic band or something which will relieve that single pin of all that load.

Thanks for the alert and again, tell us how you go.

Roberto

There are lots of adjustments available on the matte box already. I don't have your cage, sorry. But here is just one of my (LA7200) trial-only setups: it's front-heavy at present but I am confident I'll find something just right because my rail rig also enables lots of movement in all directions.

vicharris

@roberto

The MB had that play in it from day one! Maybe I just got a bad one but I tried to shore it up but it just seemed like that's the way it is. Does yours have any play?

Also just looked at your setup. Does look front heavy! I have the Pro Aim Rail System that helps that situation out a little. I'll post a pic when I take one so you can see what I'm talking about.

Roberto

@vicharris

First take a look at the locking pin, its locating hole and then maybe also the hinges. They should look like mine. The locating hole is actually a hardened steel bushing with a machine-drilled straight sided inner hole - and a splined outside. This bushing has been pressed into the softer alloy bracket. The pin is bevelled to a near-conical tip.

If there's no play to be found in those bits, try to spot just what is moving as you tilt the tripod forward.

[My rig is only front-heavy to do lots of lens-tests, lol! I'll make the camera and MB straddle the tripod head later].

Roberto

I asked [Vitaily's] seller if they could supply an extra French flag to fit to the bottom bracket: they quoted $29 and have posted it with the shoulder rig I also bought from them in last week's deal.

vicharris

@roberto It's the pin inside the locking point. It seems the pin doesn't extend in the machined hole deep enough. Guess I'll just attach it with a velcro strap. It's not like I don't have velcro all over the place anyways!

BTW, thanks for the info on the bottom flag!

Roberto

@vicharris

If the locking pin is stuck, try a drop of penetrating oil. Otherwise it's either not long enough, pointy enough or maybe the aluminium bracket it pokes through is too thick, the hole is off-centre or not deep enough.

Can you ask for a replacement part? I'd have got the drill out by now if I thought the hole could be re-bevelled. Likewise, if the swing-bracket is too thick, it can be shaved thinner.

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