Video from Hoverfly quad

[RTRyder]

Here's the most recent test flight of the Hovefly quad, I'm starting to get results close to what I can get from the Droidworx Hexa which is somewhat surprising considering the part that went into building the Hoverfly.

This is the current setup, a MK Hexa frame reconfigured to be a quad, 4 920 KV RCTimer motors, Graupner 10 x 5 props, MK HiSight II mount now using HiTec 5065MG digital servos, each programmed with centering and end points specific to its use for tilt or roll. Power is a pair of 3S 2650 mAh packs wired in parallel and an all up weight of just under 4 lbs.

Camera is a GoPro Hero HD with Sunex DSL355A-650-F2.8 lens shooting at 720P 60 FPS.

I was getting bored flying around in front of the house so this time I went vertical over the backyard a couple of times during the flight, as you can see the snow is really piling up here with no chance to get out to an open area to really fly at the moment.

http://www.youtube.com/watch?v=3Y1LQkvd_aY


Ken

 

[Droider]

Lens look better ken.. how easy was the change?

 

[RTRyder]

Lens look better ken.. how easy was the change?

Very easy, maybe 8 little screws to take out then the boards can be removed. With the boards out you can get a grip on the old lens with pliers and unscrew it using a wrap of duct tape to protect the lens body. They use locktite or something similar at the factory, so when removing the old lens it's a good idea to hold the boards with the lens facing down so any bits of glue fall out instead of into the sensor.

Once the old lens is off, reassemble the camera and then install the new lens through the opening in the case. Getting it started is a bit tricky as it's a very fine thread and you can't see the base you're screwing it into, so go slow and easy until it's right, very easy to cross thread it. Once the new lens is screwed in a ways then you can hook the camera up to a TV or FPV goggles and do the focusing by turning the lens until it's right and you're done.

Afterward I took a small piece of black neoprene fuel line that I use as clunk line on the gasser helis, cut it open down the length and then wrapped it around the barrel of the lens stuffing it down between the barrel and the case of the camera to seal the gap and keep moisture and dirt from getting in, worked out just about perfect for that.

Only other thing I did was remove the glass lens off the GoPro case so the now longer lens can stick through. When I have time and it's a bit warmer out I'll go out in the garage and cut an adaptor out of Delrin to put the glass lens back on the case over the end of the new lens.

Ken

 

[CopterCam]

Ken,

Nice !.....So the Sunex lense mod addresses the 'fisheye effect'. I always felt the GoPro HD had exposure issues. Will be good to see some stable footage in good light to see what affect if any the Sunex lense has on exposure.

In your pans I noticed some motion judder, what mode did you use here ?

Sid

 

[Droider]

How about some pics through the new lens ken.. I would really like to see some stills

Dave

 

[RTRyder]

How about some pics through the new lens ken.. I would really like to see some stills

Dave

I'll try and get some tomorrow weather permitting. I've been a bit sidetracked getting the Droidworx flight controller problem repaired, back in the air, and the parameters setup. I'm finding that there is enough variation in F/C production that a parameter file that worked well on one board doesn't work for crap on another! Of course that may be due to the board I just replaced being one of the original F/C 2.1 versions with the 000 resistor bodge to keep the gyros from falling off and the new one being built right, don't know for sure, just a guess on my part.

Ken

 

[RTRyder]

Ken,

Nice !.....So the Sunex lense mod addresses the 'fisheye effect'. I always felt the GoPro HD had exposure issues. Will be good to see some stable footage in good light to see what affect if any the Sunex lense has on exposure.

In your pans I noticed some motion judder, what mode did you use here ?

Sid

The jumpy pans are not in the original, it's a feature added by Youtube when they "processed" the video after uploading it! I do all the recording on the GoPro at 720P 60 FPS, some people say there's no difference visually between 30 and 60 FPS, I say BS, I can quite clearly see the difference in the recording, at least any that comes out of my GoPro HD.

Ken

 

[CopterCam]

So its the YT syndrome................well that's good, in that it is not attributed to camera or mount. I did the firmware upgrade and PAL gives me 50 FPS.

I mostly use r5 1080p and noticed a difference between it and 720p while some claim there is no difference ?

Sid

 

[RTRyder]

So its the YT syndrome................well that's good, in that it is not attributed to camera or mount. I did the firmware upgrade and PAL gives me 50 FPS.

I mostly use r5 1080p and noticed a difference between it and 720p while some claim there is no difference ?

Sid

There is a difference between 720 and 1080 and it's the width of the field of view. From the GoPro website... "The GoPro cameras do not have zoom, however you can vary the field of view by changing the resolution settings. At 1080p you will have a 127 degree field of view, while at the other settings you will have a 170 degree field of view."

The view of the 960 setting is also taller than any of the others but according to the website has the same FOV as 720.

Ken

 

[CopterCam]

There is a difference between 720 and 1080 and it's the width of the field of view. From the GoPro website... "The GoPro cameras do not have zoom, however you can vary the field of view by changing the resolution settings. At 1080p you will have a 127 degree field of view, while at the other settings you will have a 170 degree field of view."

The view of the 960 setting is also taller than any of the others but according to the website has the same FOV as 720.

Ken

When I stated 'a difference', I meant a difference in image quality. The FOV difference to me is only discernable in the Aerial shots from the extreme fisheye effect in 170* FOV.
So, it will be interesting to see what effect the Sunex lense mod. has with its FOV?

 

[RTRyder]

How about some pics through the new lens ken.. I would really like to see some stills

Dave

Here's one I just took during a quick test flight out front...

File is roughly 2.8 Mb in size out of the camera. Looks good though not as good as similar pics I've taken with the 12 megapixel Canon SX 200. This would do in a pinch, if I were out doing video and for some reason wanted to get a few stills as well and didn't have a still camera with me. If I need higher quality I'll just use the Canon with the CHDK intervalometer set for the needed timing.

Ken

 

[CopterCam]

Ken,

Very nice ! no real loss of impact with the Sunex lense mod. What is the FOV ?

For comparison, here is a recent shot from a local Castle during our uncharacteristic 'Snow' last Christmas. It is not so much the curved horizon that bothers me as they can usually be cropped but rather the bowed verticals of Fisheye lenses.

http://img577.imageshack.us/i/gopr2548.jpg/


Sid

 

[Droider]

Curves nice on women not of castle walls! Thats what I have issues with on the standard lens of the GoPro. Kens picture is very encouraging. Ken can you post the link to the lens.. I am sure I could find it with some effort but I am just starting to build me new HisiteII mount

 

[RTRyder]

Ken,

Very nice ! no real loss of impact with the Sunex lense mod. What is the FOV ?

For comparison, here is a recent shot from a local Castle during our uncharacteristic 'Snow' last Christmas. It is not so much the curved horizon that bothers me as they can usually be cropped but rather the bowed verticals of Fisheye lenses.

http://img577.imageshack.us/i/gopr2548.jpg/


Sid

According to the manufacturer specs the lens FOV is 84 degrees and the Full frame FOV on the 1/2.5 sensor the GoPro uses produces an FOV of 70 degrees. At some point I want to do a back to back comparison using the mod'ed GoPro and the stock one on the same scene to see just how much of a difference there is between them. I don't know what the effective FOV is for the standard GoPro when taking stills though it could be as high as the 170 degrees it uses for 720P, I doubt it is that high as the stills from the standard lens don't seem quite as distorted as 720 video can be.

Curves nice on women not of castle walls! Thats what I have issues with on the standard lens of the GoPro. Kens picture is very encouraging. Ken can you post the link to the lens.. I am sure I could find it with some effort but I am just starting to build me new HisiteII mount

Here's the link to the lens data sheet... http://www.optics-online.com/OOL/DSL/DSL355.PDF and the USA based home page of the manufacturer http://www.optics-online.com/default.asp They do have a French and German distributor listed, may be easier for you to order from one of them than from the US... http://www.optics-online.com/Profile/representatives_and_distributors.asp

Ken

P.S. the antenna's sticking up off the tops of the towers kind of ruin the ancient castle theme, or are those flagpoles? Either way they don't quite fit to my eye...

 

[CopterCam]

Agreed, the curves really spoil the image but that is a feature of 'Fisheye' lenses. It is really evident how much distortion there is from the 'flagpoles'.

A stock GoPro and a Sunex GoPro stacked atop each other would be good for a comparison......... is this 'Sunex' the best choice of lense for the GoPro ?

 

[RTRyder]

Agreed, the curves really spoil the image but that is a feature of 'Fisheye' lenses. It is really evident how much distortion there is from the 'flagpoles'.

A stock GoPro and a Sunex GoPro stacked atop each other would be good for a comparison......... is this 'Sunex' the best choice of lense for the GoPro ?

At the moment I believe it to be the only choice other than the stock fisheye. There are a lot of folks looking at replacement lenses and a few have tried different ones, but so far the Sunex is the best I've seen for a direct replacement. I've also seen a solution that's somewhat of a bodge involving putting a different lens on the case that straightens out the fisheye but it tends to produce a barrel effect around the edge of the frame and to me is not even as good as using software in post processing to remove the fisheye.

Ken

 

[CopterCam]

Interesting...................I wonder if a wide angle adapter is available or could be modified to bring a bit more FOV to the Sunex lense ? It appears that GoPro are not interested in this idea, our AP/AV needs are much different to their target market.

Here is a frame grab from a recent video, I selected this frame because there is a horizon and vertical. I used 1080p, interesting that this frame grab shows the curved horizon but good verticals ?

By coptercam at 2011-02-11[/IMG]

Sid