Odd Photos with FPV Traansmitter Connected

DaveTown · May 12, 2014

I use a Mobius Actioncam for my aerials, and it has worked great up until now. I recently added an Immersion 600 mw transmitter, and that works great for videos. When I switch the camera to photo mode, I get a photo of the target, and then under that image a pink and green image of the target, and then below that, the target again, this time split near the middle, and the sides of the image are swapped. All this is in the same JPG file...

Anyone seen this before, or know what to do to attempt to fix it?

Thanks to all for your help.

DaveTown · May 13, 2014

Guess no one has seen this...?

Adriaan24 · May 14, 2014

All I can think of is .. Do you also have this issue when your not flying within 2 meters range of power lines?

More seriously (although that could have some effect potentially), a picture of the setup/wiring might prove useful in diagnosis. How are the JPG's stored with this Mobius Actioncam? SD?

ElGuano · May 14, 2014

Moved to FPV forum.

DaveTown · May 14, 2014

Adriaan24 said:
All I can think of is .. Do you also have this issue when your not flying within 2 meters range of power lines?

More seriously (although that could have some effect potentially), a picture of the setup/wiring might prove useful in diagnosis. How are the JPG's stored with this Mobius Actioncam? SD?

Yep, the Mobius stores the photos as JPGs on a micro SD card (SanDisk 16GB Ultra - UHS speed class 1). As for the wiring, there is a store bought cable from the usb port on the camera to the video in port of the Immersion tx. That is the only connection to the camera. The tx is connected to a power tap off the phantom battery. Nothing fancy. This all works 100% fine when the tx is powered off. Also, video capture is fine whether the tx is on or off.

Just for the heck of it, I wrapped the camera in aluminum foil thinking that sheilding it might help, but there is no change in the photos.

Oh, and the alleged proximity to power lines also has no effect.

Am I going to have to spring for a GoPro?

Thanks for your time.

Adriaan24 · May 14, 2014

Hi DaveTown,

It doesn't really look like an interference problem to me indeed. I'm thinking about two possible issues that cause bad writing to the SD.

- The Sandisk class 1 card.. It's defininately worth a shot upgrading to a class 10 card because of faster writing speeds. Especially since Sandisk has a reputation for not living up to their "promised" writing speeds. If somehow the camera gets more busy because it has to send a signal to the TX then there's less time to write the file which means more writing speed required on the SD. It's just a theory though but it's something I'd try for sure.

- The powder load. I'm not sure how the camera is powered but the combined load of the TX and the camera might cause low voltages when writing to the SD resulting in corrupted files/images...

[edit].. then again it's only happening in picture mode? Is there some kind of combined video + picture mode like what GoPro has?
Hope that helps!

DaveTown · May 14, 2014

Adriaan24 said:
Hi DaveTown,

It doesn't really look like an interference problem to me indeed. I'm thinking about two possible issues that cause bad writing to the SD.

- The Sandisk class 1 card.. It's defininately worth a shot upgrading to a class 10 card because of faster writing speeds. Especially since Sandisk has a reputation for not living up to their "promised" writing speeds. If somehow the camera gets more busy because it has to send a signal to the TX then there's less time to write the file which means more writing speed required on the SD. It's just a theory though but it's something I'd try for sure.

- The powder load. I'm not sure how the camera is powered but the combined load of the TX and the camera might cause low voltages when writing to the SD resulting in corrupted files/images...

[edit].. then again it's only happening in picture mode? Is there some kind of combined video + picture mode like what GoPro has?
Hope that helps!

Thanks Adriaan,

I tried my other SD card, a class 4 SanDisk. Same issue with the stills. Dang!

Checked the camera manual, and it states, "For the best compatibility use cards with a class 4 rating if you have them. There is absolutely no advantage in using cards with a higher rating."

And so I'll poke around a bit more, hoping to find some other reason that could be causing my issue.

Again, thanks for your input.

D.T.

DaveTown · May 16, 2014

Here's a quick update...

I spent some time experimenting yesterday, based on information that Adriaan suggesed to me. (Thanks Adriaan). I changed the delay time between photos from the 0.25 seconds that i was using to 5 seconds, just to see what would happen. Powered up everything, took some photos, and checked the results. The shots were perfect! So then it was a matter of finding out how frequently I could take a picture and still have the camera store them properly. It turns out that one photo every two seconds is the max while the transmitter is on. So happily, i dont need to switch over to GoPro for my aerial stills. I hope this info helps someone down the road. No point in having to reinvent this wheel.

Adriaan24 · May 16, 2014

Good to hear DaveTown! If doing what you did indeed fixes it, the theory about writing speed holds up

I would assume 2 second per photo is frequent enough for this purpose, otherwise a class 10 card might still alow you to write pictures to the SD 4 times per second (if the camera is compatible with class 10).

Anyway, happy flying/photographing!