Hero2 in GoPro flat port housing see the port sides

[alcina]

I picked up a GoPro flat port housing (with red filter) from Reef Photo & Video while I was back in the US a few weeks ago.

I'm seeing the edges of the inside of the port when I shoot underwater. What am I doing wrong??

 

[Marty Cerven]

This is a design limitation of the small drop in lens replacements, by simply replacing the stock round lens with a flat one the 170 fov modes and phot modes will all cause vignetting.

Here is an example video I made a while back showing a few different flat lens options, this was all using a HD1 but HD2 cams will have similar results.

The Occulus r5 lens is similar to what you would have bought and the eyeofmine and Blurfix are much larger flat lens fixes that have no issues in wide video modes due to the way they are designed to avoid this issue. All these drop in lenses will have some form of vignetting but due to the gopro manufaturing tolerance of the housings the location of the black edges may vary from housing to housing.

[video=youtube;WlCvDaDrUss]http://www.youtube.com/watch?v=WlCvDaDrUss[/video]

If you stick with your lens the only way to avoid the issue is use only the medium and narrow modes or upgrade to something like the Blurfix which not only fixes the focus issue and is the lowest vignette level of all fixes Ive seen. It also can easily accept URpro underwater filters to help correct some of the Blue video effect when filming underwater in natural light.

 

[Nitro91]

woah great video there martin^^^!!!

couldn't have a better video for comparisons
the red filter makes such a difference

 

[Marty Cerven]

Thanks Nitro, The filters do make a huge difference and if you see my more recent test even though this only shows a stock housing vs Blurfix housing with and without a URpro swCY filter its amazing the difference. I was originaly going to do this with the other flat fixes I have but since using the Blurfix I found a good filter is almost as important as the focus fix so I just wanted to test this more. The drop in lenses still get vignetting in all wide angle modes so it would just be a reshoot of the orignal test I made.

First part of the video is at around 2.5m with no filters and HD1 and HD2 cam the second half shows this at 4.5m with and without the filter showing how much colour is lost at even such a shallow depth without a filter. Slightly more interesting subject matter here

[video=youtube;ThWjQpYrJMk]http://www.youtube.com/watch?v=ThWjQpYrJMk[/video]

This video also shows how the HD2 has even less vignetting when using a blurfix vs the results with a HD1, this is most likely due to the HD2 lens extending out a little further from the camera body. This is also the reason for the issue discussed in this thread and people with the drop in type lenses and a HD2 underwater should read this and ensure their camera and housing don't have this issue. The Blurfix keeps the original housing in tact and still uses the round housing lens so it doesnt have any such issue apart from giving a lower vignette result.

 

[alcina]

Marty -

Thanks for the information

I'm going to have play with medium and see how that goes for me. I actually bought this as a little fun toy so don't really want to invest more than I already have or make the unit bigger, if I can possibly avoid it and still enjoy playing!

It seems I can only select this in 1080? Is that the correct setting for underwater shooting, do you think?

 

[TXreefer]

Great comparison videos. I can't wait to get mine!

 

[Marty Cerven]

Marty -

Thanks for the information

I'm going to have play with medium and see how that goes for me. I actually bought this as a little fun toy so don't really want to invest more than I already have or make the unit bigger, if I can possibly avoid it and still enjoy playing!

It seems I can only select this in 1080? Is that the correct setting for underwater shooting, do you think?

The HD2 only has these options in 1080P mode same as the original gopro HD which the drop in lenses would only work in 1080P mode as it was the only 127 fov mode available. Gopro have mentioned that multiple FOV's will be available in 720p modes in a future HD2 firmware upgrade. 1080P medium isn't a bad option though I prefer to use the widest modes and get close to the subjects getting more into the frame without being too far away from the subjects so there's not too much water between the camera and my target. With the medium mode you dont have to get as close but this means there is more water between the camera and subject so colouring wont be as good.

I mainly use 720P60 1080P medium and wide modes but I like to experiment with all the options a bit. You can use 1080P narrow mode but due to the way it gets the image from cropping the image from the central part of the sensor it suffers in anything other then very good light.

Your other alternative is to film in any modes and zoom the image in editing to eliminate the vignetted corners, you will be losing some resolution though so limiting to medium fov is still you best option I think with a drop in lens.

 

[alcina]

Ah, I didn't see the little * by the 720 in their FAQ - wondered why I couldn't change mine in 720

Yes, adding another piece is clearly the best option, but at this stage I'm willing to compromise and not spend any more money on something I'm only using as a bit of entertainment (at least for now)!

Thanks, again. Looking forward to getting out and trying the medium mode in the water.