Tuesday 24 May 2016

Comparing a DIY goggle to a retail goggle

Hello, if you recall I wrote a popular how-to guide to building your own fpv goggles. This was back in 2014 and things are moving along in the world of fpv.

Business is improving for me, and I recently got a pair of ready-made fpv goggles and thought I would make a review and comparison to see how things have changed.

The goggles I have now, are by a company called Tovsto who were displaying products at this years CES 2016 show and appear to be quite similar to Headplay HD goggles.

I got them from Gearbest at this link after reading about the various types of goggle on the market and trying to find a good deal to suit my needs. I looked at all the usual locations and found that these were currently on discount so click... checkout.

For the last couple of years I have mostly been flying using a monitor mounted directly to my transmitter

this has proven a general success for me, as I have had zero crashes and always have been able to use the data displayed to locate and recover if I get lost in unfamiliar territory. I like that I can glance up at the sky if I need to check my orientation. orientation helps buckets, when flying via a monitor, which is why we also tend to use OSD data when flying to help us know where we are, how far/high we are, and how to get home.

(My view from the TOVSTO goggles)

What I see when i'm flying, i'm usually concentrating on the digits and arrows more than the sky or trees as once you're up high in the air there's nothing to crash into - you're completely free to roam. The rate of Altitude increase/decrease is deathly important, direction to home arrow helps when lost. 

Once I had the grasp of flying using a monitor, I decided like most DIYers, to see if I can craft a set of goggles using some cardboard, a fresnel lens and a strap. It worked for the most part. It blocked out most of the sunlight and gave me a more 'closed' viewing environment. They were a bit front-heavy and would droop down my face a bit, but for practically no money, they were fun.

(DIY and Product)

So, "how do they compare to a purchased pair?"

This is a common question, and up until now I have not really been in a position to compare or answer this as appropriately as I would have liked. But now I can, and well, how do they compare?

Image would be a good beginning point. Here is a side by side:

On the left is my monitor, on the right the goggles

Here's a closer comparison of image quality
left is monitor, right is goggles

What is my subjective opinion on the image? It appears to be similar at first. This is because of the resolution limits of transmitting old-school analogue/composite video over 5.8ghz transmitters. A 5.8ghz transmitter will transmit to both monitors the same picture regardless of pixel ratio of the screens, and it will appear very similar.

The advantage of the goggles are that they block out all light, eliminating sun reflections on the monitor screen. We all know how hard it is to view our smartphone out during a sunny day, it's almost impossible to read articles. By covering or blocking out the sun using goggles we can see much more clearly, we just look a bit silly when doing so...I mean look at this guy:

we only have to search silly man with fpv goggles to see how and why we as men should not really be allowed to walk the streets after dark.

The nice thing about the Tovsto goggles are that they do actually broadcast 1080p 60hz using the HDMI port on the top. I thought what better way to test this out than to plug in my Chromecast and see if I can stream porn youtube videos through them. It appears that after a little cutting I could connect a mini-to-full hdmi adapter I have from a Raspberry pi zero, and plug in the chromecast quite easily

Once connected, I am able to see that the monitor has switched to HDMI 1080p 60Hz mode

(See, it says so in green in the corner)

The chromecast boots up

The picture is lovely, to choose a word. It is bright, crisp, clear, pleasant to view, and there is hardly any pixelation. God bless HDMI. This 1080p would work well with DJI Lightbridge or Connex HD systems, or even my up-and-coming DIY digital HD system!

Here is a piece of footage to show the video chromecast shenanigans

Works for me fappityfapfapfap...

Anyway, so how do the goggles perform as FPV goggles? Well, here is some more video footage showing as best I can, obviously, I can't fly around with a camera stuck inside there it would be tomfoolery. But here is my best test so far

For flight footage I need to think about how I can get footage. I have a DVR I could hook up but the DVR only records 640x320 pixels. I might try flying with the monitor and have someone hold a camera inside the goggles for me, bear with me one that footage, I'll plan it and make some magic happen.

So what do I like about these goggs?
- I like the image quality over HDMI
- I like the lightweight setup
- I like the quality of the mushroom antenna, it bends nicely

- I like neat storage bag that comes with them, it will help me to keep them clean and free from dust and scratches

- I like that the channel selecting is automatic. The goggles auto search when powered on, you also have a small press button which will search for signal

- I also like that these goggles have an inbuilt speaker which produces static when the receiver video fades out to static (they avoid blue screening). This is a nice audible warning for me, I do wish fpv systems incorporated audio more as I think hearing your quad or plane helps you know how the motors are responding and this helps you fly more accurately on the whole. I have a 5.8ghz transmitter with audio so perhaps I will test this out on these goggles.

What do I think could be improved upon? after all, nothing is perfection right? Well, I think the HDMI slot on the goggles could be more accommodating, it's a bit small. It is a mini hdmi port, but to fit an adapter in there you have to snip some of the foam. It's a simple solution and doesn't cause damage. I would also like to see a headphone jack. I'm sure this is an easy DIY addition, but I would have liked to see it installed already.
Also, I would like to see the goggles have an included adapter to allow a user to connect a standard 2s lipo, and lipo alarm. The included battery is an enclosed unit that simply warms the user, then shuts off the monitor - I have no idea what the voltage of this battery was/is when it shutdown. the charger is a 8.4v 1 amp wall adapter with charge on/off light.

 If I am attaching a lipo battery to the back of my head I want to know that it is safe, and charged correctly or I might end up Tyler Durden 'end scene':
But I hope not.

I do think the TOVSTO goggles are an improvement for me and my own setup, I also think they are better value than headplay, better quality than quanum, and the single screen is better for my eyes than side-by-side cardboard goggles. I don't think single screen fpv goggles are going to compete with sbs goggles yet, the plain, simple view is beneficial to pilots and their ability to control aircraft.

1 comment:

Henry Fields said...

Did this require any predictive modeling, or feature engineering?