S800 alternative props

BorisS

Drone Enthusiast
Those Red Bulls are looking strong. When you say Mclaren have lost the best driver, did you mean Alonso or Vettel? Just kidding. I know you meant Hamilton.

Back to the subject of the S800. I do own the S800 and Z15g. While I don't think it is perfect, I do think it works very well out of the box. The vibrations are a bit worrisome and the gimbal does have some odd initialization behavior. That being said, the system masks those problems very well. I also think DennyR's prop adapters will go along way to reducing the vibes. I just received mine and will be trying them in short order.

Here are some issues I have seen:
The minimum yaw rate for the WK-M needs to be a bit slower. When operating the Z15 in orientation lock mode, the yaw is too fast.

The Z15 video converter does not work with NTSC, only PAL

The props do lend themselves to vibrations either from their construction or aerodynamics. I occasionally get harmonics at different RPM's. Yes I have balanced them on a magnetic balancer in all orientations.

Initialization on the Z15 is not consistent. It does seem to correct itself after a short time.

The landing gear need to be retractable.

Forget balancing the original props. Even if balanced perfectly they have a tracking problem thus will always cause vibrations etc. It was announced somewhere that DJI themselves are looking into different props now. The same ones are available at himodel for a 1/3 or the DJI price by the way ! Already had the HImodel version in hands and they are the same !

Concerning the startup routine just noticed the same. Had a second GH2 Z15 at my place today and although the same FW they do a different dance ! One of the Z15 Gh2 actually also changes the way it calibrates itself, its always a little different. My GH2 Z15 always does the same routine thus strange one.


retractables were already shown at the photokina and will be released soon by DJI. Question though if for the GH2 version especially they make any sense. In 108050I I would try to avoid a lot of panning around.

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Concerning the Horizon level issue/speculation, I personally think its a little silly to pull out two videos were we have no background info how it was used, trims correct on the Radio, maybe gave a slight roll input during panning or tilt however the radio is setup etc. and stamp the zenmuse to have an issue staying level. Especially because all these were running on an old FW !

Boris
 
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BorisS

Drone Enthusiast
What if any changes have you guys made to the WK-M stability settings after changing props? More specifically the APC 14x4.7 and the Xoar 15x5

Best is just put the gains on your radio and test it out. The s800 with the zenmuse in combo has stopped the whole gains fiddling for me. One doesn't have the direct feedback anymore if these or those gains result in smoother footage, since the z15 smooths out the disturbance anyways. See what give you the best feeling and thats it more or less. I prefer lower gains than it can actually take or would need, because in my experience the higher the gains the shorter the flight times and the more the ESCs and motors warm up !

In general though with heavier props which the Xaor and the APCs are compared to the original CF DJI props the higher the gains showed be, if we were going by the old standard of not having a zenmuse the smooths it all out anyways !

Boris
 

Nicoleto

Member
Stacky

I think this horizon issue is a bit of sour grapes, If I were making commercial camera mounts I would be knocked sideways by the level of advanced technology that DJI are using. However, even if the horizon did move a fraction over a few mins. so what. The camera operator is supposed to be flying the camera all of the time and he would see and correct this.

As most TV broadcasters are using 720 HD these days one could say that even 1080 is overkill. Yet a lot of commercials are shot at 2 or even 4k to create a sort of status. I read recently about a scene test of all of the top cameras with some 5D's and below thrown in the mix. They were all edited by a top company and then a panel made up of directors was brought in to blindly evaluate the results. The top scorers were not the top cameras. Hacked GH-2's did well.

If you are shooting for a "coming to a cinema near you" production then yes 4.5 K red epic is the tool for the job. Not too much of that work outside of Hollywood I'm sure.

You are right Denny

Look at minute 26:59



Regards
Nick
 
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DennyR

Active Member
Nick that sums it up very nicely

A few years ago when I was shooting vertical mapping stuff from my old Wilga I was using a very dated 9x9 camera. Someone from the Environment agency called me and said that an inspector was going to check my aircraft in a few days to see if I was using FMC camera (a highly expensive mod that moves the film during exposure in accordance with your ground speed.) So I made a name plate with the letters FMC . When the guy came he stuck his head in the door looked at the camera and ticked the box. The work was always good enough before so why change it to suit the bureaucracy.
 

jes1111

Active Member
VERY interesting - thank you for pointing me to that series. Leaving aside all the irritating platitudes ("It's the plumber, not the wrench.") - you have to watch all three parts to get to the truth. Part 3 is the most revealing - where they show the scenes in ungraded and graded with the same lighting from each camera. Then, and only then, the truth jumps out at you. The more expensive cameras give you much better "clay" to work with. Period. Dynamic range, banding, aliasing - if you don't know what these are or don't care too much about them then an NEX5 or GH2 is just fine for you. If you are going to run down the 8th hole at at a golf club at midday on a sunny summer's day, then the NEX5 or GH2 are fine for you. If you want to get a great result under difficult/extreme lighting conditions - in low light or where there's a huge brightness range - and you don't want to spend hours and hours beating up your raw footage to overcome the failings of your camera... then spend some money on a better camera :)

Personally I loved the ARRI Alexa - its ungraded footage was exactly what I look for with the raw stills I work with - damn good "clay" with a fantastic dynamic range. I love how it held detail and colour in the shadows. I was, frankly, a little disappointed by the RED Epic - but that could be because an an architectural photographer I'm more concerned with keeping shadow detail than losing highlight detail: the Epic seemed to me to favour the highlights more. The GH2 and 7D produced exactly the images I'd expect - punchy, saturated right out of the camera but at the expense of detail in both highlights and (particularly) shadows. I felt the lower end Sonys had that overprocessed "video look". The C300 would probably be my choice for MR aerial work as the best balance of image/price/weight.

Coming back to the topic (kinda)... the GH2 produced highly credible results with a Fujinon 18-85 cine lens ($85,000 of lovely glass) and world-class colorists and post-production gear, not the Panasonic 16mm pancake lens and and a quick run through iMovie. It's this restriction on the glass that is, for me, the big issue with the Zenmuse and the dynamic range that's the limiting factor of the GH2.
 

DennyR

Active Member
... and it's exactly this which, to my mind, excludes it from the category of "pro gear". It's like the "idiot modes" on a camera - that kind of hand-holding by the manufacturer clearly indicates the target market.[/QUOTE]




If one were to make this gimbal fully adjustable so that it would fit a number of different cameras then it's design would have to be compromised in order to do that. Weight and accuracy would suffer.
 

jes1111

Active Member
If one were to make this gimbal fully adjustable so that it would fit a number of different cameras then it's design would have to be compromised in order to do that. Weight and accuracy would suffer.
Actually - looking at that video of re-balancing the Z15 - I have to disagree with you. It would add no significant additional weight to have made the over-bridge adjustable. The base plate arrangement as it exists is fine for fore/aft adjustment - again, could easily be made to do the same left/right (if it doesn't already). The lens ring is a curious thing - I would use the hotshoe as the top brace point. The only limitation is obviously the clearance at the back - but then I can't see the point of allowing the camera to rotate that far anyway - there's no valid reason for it to go within 45º either side of "facing backwards". The Zenmuse is already (I think) the heaviest gimbal in this field. It could definitely have been made lighter with some composites (but that would cost more to manufacture) but a bit of additional work could undoubtedly have made it adjustable whilst retaining its current weight. There would be a maximum weight limit, of course (which they could quote). I don't see why "accuracy" would have to suffer.
 

DennyR

Active Member
Actually - looking at that video of re-balancing the Z15 - I have to disagree with you. It would add no significant additional weight to have made the over-bridge adjustable. The base plate arrangement as it exists is fine for fore/aft adjustment - again, could easily be made to do the same left/right (if it doesn't already). The lens ring is a curious thing - I would use the hotshoe as the top brace point. The only limitation is obviously the clearance at the back - but then I can't see the point of allowing the camera to rotate that far anyway - there's no valid reason for it to go within 45º either side of "facing backwards". The Zenmuse is already (I think) the heaviest gimbal in this field. It could definitely have been made lighter with some composites (but that would cost more to manufacture) but a bit of additional work could undoubtedly have made it adjustable whilst retaining its current weight. There would be a maximum weight limit, of course (which they could quote). I don't see why "accuracy" would have to suffer.

This all sounds like a recipe for another disaster...... After you have made ten prototypes you will then give up. Your ARRI Alexa will never leave the ground let alone earn any money. Going from a button pusher to a DOP is light years away.

I bet you have not even considered how all of that wiring can be contained in a near friction free bearing etc. When you make the overhang of the roll axis longer to fit a bigger camera then you will place too much overhang load on the bearing. Even the Cineflex is a dedicated system to three lens choices and the camera body is just a remote imaging sensor. Why do you think it runs in air bearings....
There is no such thing as a jack of all trades that works properly. Even the HDMI cable should be tied down which was not done in that video. I would also say that it looks like he has bent the frame as it is not spinning as freely as my own one does.

The mechanical solution is small in comparison to the electronics. They could have reduced the weight very slightly and then when it takes a knock it will not work properly. The design is much more advanced than you can begin to imagine. As for the Hot shoe mount I don't use any of that lens ring assy.

As for high dynamic range and shallow depth of field requirements used in Cinema productions they are not required for daytime aerial work as the lighting is determined by the weather, time of day and the angle that you shoot from. The 16 mm lens works ok if you use F8 and crank up the ISO, not the recommended full bore as per the DJI manual. For night shots the Nex-7 is not as good as the 550D. I expect the Canon M will be made to fit the Zen without too much trouble.

Jeremy, Don't let me put you off from trying though.....

BTW do you know how much the ARRI costs.
 
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JDM66

Member
Hi question: is it normal XOAR new blades should they be balance again ? mine seem to need ! thank's for support jdm66
 

jes1111

Active Member
Denny - you've switched from "nobody's as good as me" to "nobody's as good as DJI". Makes "conversation" and the "sharing of knowledge/experience" rather difficult ;)
 

DennyR

Active Member
Denny - you've switched from "nobody's as good as me" to "nobody's as good as DJI". Makes "conversation" and the "sharing of knowledge/experience" rather difficult ;)

That seems to me to be a full admission that you have run out of backhanded stabs at the product that you would like but cant afford. Or is it that you just want to ponce information that took DJI a lot of time and money to develop. Out of respect for those who have bought the product why should you be given free access to the benefits of joining the club.

Just go ahead and do something instead of talking about it. And then show us....

Something....Anything.... But no more personal attacks on the Chinese or me for that matter.

At least a 120 people are sharing the experience of what this thread is all about without difficulty it would seem.
 
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jes1111

Active Member
No, Denny, it was a (remarkably calm) reaction to your last aggressive, condescending post. It would be beneficial to all (and I keep hoping) if you could share your extensive experience in this field in an open and friendly manner instead of this "DennyR knows best" attitude. Challenging with "more advanced than you can begin to imagine", "I bet you have not even considered" and "you would like but can't afford" is playground stuff!
 
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ChrisViperM

Active Member
DennyR vs. jes111....Cyprus vs. Portugal....always good for epic battles :tennis:

I have to admit, I've learnt a lot from both of you, and I like both of you a lot.....it hurts to see you two having a go at each other. Life is too short for this....


Chris
 


gregs

Member
Denny, I'm heeding your advice and going with the APC's. I've received your hubs and want to know if I should just use the collars that the props were shipped with or drill the centers out and use those sleeves that you shipped with the hubs. These hubs are real nice, BTW.

Thanks,
Greg
 

BorisS

Drone Enthusiast
It a really bummer just wanted to cruise out to salzburg take the s800 along and after reading the latest mishaps in RCgroups i think i will leave it on the ground again. Although i trust DJI to take care if something happens, the hassle it just to big ! Getting a little frustrated about this and to consider all this user error just can't be !

Boris
 



DennyR

Active Member
It's sad reading but I trust my own S800 as do many others. If there are any issues left I think it is in the ESC's'/distribution board.

My theory is that the Flip of death is the result of a motor loosing phase sync. and stalling. then the nearest motors instantly try to correct the tilt which results in them stalling also due to the rapid response demand. As the copter starts to fall the opposite motors go to full power to arrest the sinking. They are unaware of what the other motors are doing so the model flips on full power. If it is not the phase sync. then it could be a simple wiring problem, Carbon will short circuit like is was copper. It takes no prisoners if the circuit is faulty. Maybe we should be using fiberglass prepreg instead.
 
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anyvision

Member
denny can you tell me what Frequence you use on the 1.3ghz tx.? me i have still little Signal strength loss on my 2.4ghz graupner gr 24 receiver!
 

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