Best low-cost cam that can match the *still photo FOV* of a Hero 4 Black (not the quality)

[Aussiemandias]

Is the ActiveON DX camera my best bet? I don't need to match the image quality of the Hero 4 Black, just the FOV, although a decent photo would be nice. And can I hack these cams to do bracketed shots?

Here's my panohead rig.

[Aussiemandias]

The Yi Action Camera 16mp fits the bill, it seems: https://roundme.com/tour/147036/view...n0qfV9CyWmyHFA. I'm guessing the Git2, which has the same sensor and a 170-degree lens will do it too. But the Git2 is a bit expensive for my project. Any others that are cheaper and can still so the job?

[nutsey]

Eken V50 Pro with 13MP Sony IMX258 sensor can be found on Aliexpress for ~$50.

[nutsey]

Aussiemandias I've modded the V50 Pro cam's firmware. Now it can shoot 4160x3120 JPEGs with 98% quality. The HFOV is ~125 degrees. I'm going to test its pano shooting abilities one of these days (the weather is bad right now).

[nutsey]

I've just compared Activeon DX vs Xiaomi Yi Z26. The Yi has noticeably wider FOV, but the DX is brighter and sharper. I'll post a couple of samples later.

[nutsey]

Both cams are based on same Ambarella A7 SoCs capable running ambashell scripts so you can use stuff like RAW shooting, expo-bracketing, AE-lock and so on.

[Aussiemandias]

Thanks for this! It's very helpful. I'll share the panohead redesign in .STL format once I have it worked out. BTW, does the active on have a 1/4"-20 thread in the base? I would be more secure than the current snap-in with loop system that I'm using.

[nutsey]

Unfortunately the DX has no embedded tripod mount.

[nutsey]

Here we are. I've tested 4 somewhat budget cams that can be (or not) interesting for using with panohead.

Activeon DX. Ambarella A7 + 12MP IMX117:


GoPro Hero 2014. Ambarella A7 + 8MP AR0833 (I used a scipt to avoid software 5MP limitation):


Yi Discovery. Allwinner V3 + 8MP IMX179:


Xiaomi Yi / XiaoYi rev.Z26. Ambarella A7 + 16MP MN34120:

[Aussiemandias]

The active on is the best IMO. Best price to performance that is. The FOV might be less of an issue is seems if I just modify the panohead. It's a simple system that allows three shots up and three shots down, which works for the Hero 4 Black, but all I have to do for a cam with a more narrow FOV is to add another shot top and bottom - i.e. 4 shots top and 4 shots bottom. Higher res image overall and better overlaps. I have to do some quick prototyping, but my 3D printer is out of action and I'm unwilling to pay someone else to print.

[Aussiemandias]

I'll start the redesign and maybe pay for one print then refine once I get the part for my printer and I'm back up and running

[Aussiemandias]

Is there any way to coax some extra FOV out of the Activeon DX?

[nutsey]

I've measured ~115-degree HFOV for the fullframe sensor readout.

[nutsey]

What do you think about an action cam capable shooting square (1:1 ratio) stills? I think hor./ver. distortion uniformity could provide better results in spite of the possible need of additional shots.

[Aussiemandias]

At this point, I'm looking for simplicity with my panorama head design. I've increased the number of shots it will take to 8 (4 up and 4 down). There still needs to be overlap between the edges between up and down photos and I'm not sure how I'd design the rig to do shots in the middle if I went for a 1:1. Maybe have a rotating mount at the end of the stalk with 3 'click' stops - 4 up, 4 middle and 4 down. I'm giving this to students, so I wanted something that wasn't hard to use. It also increases the number of shots to be stitched. I'd be doing the stitching as a service, so that increases effort and time on my part. Still, definitely worth thinking about.

[nutsey]

Do you think an 8MP cam can be enough for your needs?

[nutsey]

This is what we can get with from lower priced 8 Megapixel cams (~$30 each).

MSTAR 8328Q + 8MP Sony IMX179:


Allwinner V3 + 8MP Sony IMX179:

[nutsey]

Xiaomi Yi Z26 with my favorite M12 fisheye lens. Shot in RAW. Coverted into DNG with this tool. No additional processing except debayering with imagine plugin.

I guess the FOV here should be very close to 170 degrees.

[nutsey]

Aussiemandias

[nutsey]

The first try of my rig (3x3 unprocessed JPEGs): https://goo.gl/maps/dvwssQnDo1F2

[Aussiemandias]

That looks pretty good. You're in Russia? But it doesn't quite fill in the nadir. I'm guessing that the cheaper cams wouldn't even do that much?

[nutsey]

That looks pretty good.

Thanks!

You're in Russia?

No, I'm not.

I'm guessing that the cheaper cams wouldn't even do that much?

I'm going to try some adjustments today. Hope shooting in RAWs could improve fine details and highlights clipping.

[Aussiemandias]

Sorry if I caused any offence there about your location. I just saw the statue and assumed you might be there.

[nutsey]

No problem at all. The location on the map indicates the city and the country of my current residence where I moved from Moscow, Russia quite long ago.

[nutsey]

RAWs are much longer to process, but more details and wider dynamic range can be obtained that way: https://kuula.co/post/7YNy7

[Aussiemandias]

My comments on Kuula. Nice sunset!

[nutsey]

Aussiemandias Is there a way to get rig of such stitching artefacts?: https://kuula.co/post/7YNBd

I mean do I have to manually adjust each fragment in PanaramaStudio? Are any improvements possible as well with thing like using the proper focal length of the lens?

[Aussiemandias]

I'm still trying to work this one out myself for the Xiaomi Yi Action Cam. I realized that I didn't sell them after using them to make 360 videos. But they still had the 220-degree lenses in them, so I had to locate the originals and put them back in. I'd ruined the lens surrounds when I did the original mod, so that even with the lens focused as good as I can get it, there is a little light bleeding in it seems. No matter, if this works then I'll buy some new ones. I've seen them for about fifty bucks on Amazon Canada, which is right in my price point for this project. I tried a quick test and it partially works, but I have the same problem as you did - the zenith and the nadir are still not filled in. I think that with a change to my panohead design (currently printing), I can get rid of those. But also, as you say, there is the small matter of getting the Panorama Studio settings correct. Using the EXIF from the camera doesn't work, but I can't use the settings from the GoPro, so I'm still trying to figure that out. If you come up with a winning solution, please let me know.

[nutsey]

"hey still had the 220-degree lenses in them"
What lenses are these? I have two different M12 fisheyes with ~150 and ~170 degree HFOV (measured today).

"the originals and put them back in"
They should have square holes on the 'lens barrel'. BTW Yi cams came with 3 or 4 different lenses for different hw revisions.

"I'd ruined the lens surrounds"
I belive I saw that type of M12 lens holder somewhere online recently.

"the same problem as you did - the zenith and the nadir are still not filled in"
I thought I had managed to fill them both. See my latest link above (a sports ground).

"If you come up with a winning solution, please let me know."
Sure. The problem with the Panorama Studio is that it lacks any manual lens distortion adjustments... Normal/fisheye is definately not enough, because many lenses have more complicated distortion profiles like 'moustache'.

[Aussiemandias]

I modified two Yis a couple of years ago with 220-degree lens to do this: http://www.martinjohnsmith.ca/360vr-...-in-360-and-vr
When I found them in a drawer a few days back, they still have those lenses in them. I have to find the lenses that I removed and put them back. Anyway, I finished printing my panohead today and gave it a quick test just now. Here's the result. It's not intended to win awards, just prove that the panohead works. As you can see, it has stitching errors, which is why I need to calibrate Panorama Studio to work with the Yi.

https://veer.tv/photos/324928

"I thought I had managed to fill them both. See my latest link above (a sports ground)."
At the time I read your response, I hadn't seen the sports ground image.

[nutsey]

What's the hw revision of your Yis (Zxy under the battery)?

[Aussiemandias]

[Aussiemandias]

Is there a way to mimic the same "super wide" setting you see here on the Android app for the Yi for another camera (say, an AllWinner chipset) using some kind of hack. Especially those that boast a 170-degree FOV (only ever seems to apply to the video).

[nutsey]

This icon does not enable any kind of 'super wide', but disables the lens distortion when on instead. Ambarella A5/A7 platforms are unique allowing running many useful script commands. For almost anything else such customizations from the user side mean firmware editing which is complicated and not always possible at all.

[Aussiemandias]

Ok, so to deal with distortion, the software seems to mostly crop the image. If it's on, I lose a big chunk of overlap and consequently I get big holes in my Pano. I guess my best candidate at the moment is the original Yi. I don't need EIS or voice control or any of that other stuff for video. I just hope that they keep making that model. I could be wrong, but the closest to the original Yi action can is the Yi Discovery?

[Aussiemandias]

Alternatively, I change my design to allow for an extra line of shots to help fill in the gaps. This is a useful guide. Of course, just translate from the original German: http://www.herdima.de/fischgraetmethode/

[nutsey]

I've made some tests with GitUp Git2, GoPro HERO and Activeon DX cams and now can confirm that the Yi seems to be the best as this is the only cam with fully working AE/AWB/ISO locks in photo mode.

[nutsey]

I guess the method desctibed there does not work with fisheye lenses.

[nutsey]

Another couple that could match the needs - GoPro HERO 2 and GoPro HERO 3 Silver (not HERO 3+). They both use the same 4:3 14Mp MT9F002 sensor limited by software to work in 16:9 modes. I belive it is possible to write a script for capturing full size 14Mp stills.