CP filter

[Haydn]

can some one please confirm....
A CP filter on a drone,
My silly limited brain says
They are useless as, as soon as I adjust them to cut through the reflection I am setting the lens at a certain angle. Then when you move the drone up down left right etc you are changing the way the light hits the lens. Therefore you would have to re adjust it?


Is this not the case?
I don't want to keep telling people that they don't work.... If they do.
Please educate me. I'm Australian.
Haydn

 

[arruntus]

As far as I know CP filters are mainly used for two things:

• Reduce reflections on some metallic, glass or water surfaces.
• It enhances the blue of the sky in contrast to the white of the clouds.

Let's see if someone with more knowledge enlightens us both

 

[Eagle's Eye Video]

You are both correct...

As far as I know CP filters are mainly used for two things:

• Reduce reflections on some metallic, glass or water surfaces.
• It enhances the blue of the sky in contrast to the white of the clouds.

can some one please confirm....
A CP filter on a drone,
My silly limited brain says
They are useless as, as soon as I adjust them to cut through the reflection I am setting the lens at a certain angle. Then when you move the drone up down left right etc you are changing the way the light hits the lens. Therefore you would have to re adjust it?

So a CP can be effective, but since the degree of change is dependent on the angle of the lighting, it cannot be used for several different shots, without re-adjusting the rotation of the filter. This inherently limits it's usefulness with a constantly changing video, as opposed to a static single photo.

The video below I think gives a pretty good demo of the degree of polarization, depending on the rotation of the filter:

 

[PatR]

I'm guessing the creator of the video misunderstood what an ND filter does. They are not polarizing filters, but light reducers. His tests did not address glare, but generated a darker image. Based upon his results I'm guessing he was using Freewell filters, which cause a color shift away from natural in yellows and browns, and he's confusing that with polarization. Freewell does make a polarizing filter but as mentioned by Haydn, like all polarizing filters they are effective only when direct lighting is at a specific angle to the lens. Unless your multirotor camera is not going to change in position from take off to landing (not at all possible) a polarizing filter spends most of it's time on the camera as dead weight. The outer lens must be rotated to be effective in dealing with refracted light as the camera angles change. The best way to prove this to yourself is to fit a polarizing filter to a DSLR on a bright day and clouds in the sky and see how they work. Turn you body a full 360 degrees and keep the polarizing filter in one position on the lens, then perform the rotation again while altering the polarizer position on your camera lens. As you move the lens position up, down, and side to side you will find the effects of the filter change tremendously if left untouched. As the lens is moved to positions more aligned with lighting the ability to alter the image with the filter is lost, aside from a small reduction in incoming light, which almost all filters types do to some extent.

As filters go, I've tried both Freewell and Polar Pros on the H and Chroma. I did not like the way the Freewell's would always alter the color of the image. The Polar Pros maintain a more natural image. For those that shoot stills in RAW, if you have a good post processing program you may well find that using an ND or polarizing filter does you few favors. The light they prevent reaching the lens reduces your ability to work with the photo in post.

There's some really good articles on filters and their applications to be found in a Google search, along with You Tube videos on the same subject that were made by recognized professional photographers. They are well worth the time to review. Haydn, sell them what they want but let 'em know why they may not be happy with the end result.

 

[arruntus]

At the time I searched for information on the subject and I did find opinions that said that using a CP filter in a drone didn't make much sense. Simply because it is moving all the time and changes the angle of incidence of light which makes it useless.

Another thing is the ND filters, lowering the amount of light entering the lens will get images that are not "burned", more contrast and brighter colors. At least that's how I understood it.

I've already got the kit for the E90, I'll try and see how about it. ND2, ND4 and ND8. All I need now is the camera

 

[claudius62]

All I need now is the camera
No problem, it's Christmas soon.

 

[arruntus]

All I need now is the camera
No problem, it's Christmas soon.

jajajajaja don't be bad, I already have the camera but can't use it because of the SD card problem. With a little luck, I'll have it back on Wednesday.

What do you mean by Christmas? Is that the gift you want to give me?
It has to be the E50 to make the pair so I can make comparisons between both cameras. Don't worry, when I'm opening the gift I'll look surprised

 

[claudius62]

yes, empty box.....

 

[PatR]

Have you tried a different SD card yet?

 

[arruntus]

I'm looking right now to buy another card. Following the recommendations that you have made but it is difficult, or I can't find them in Europe or those that I find in Amazon with prohibitive prices or in the store where I bought the first one (to try to return the one that doesn't work for me) I can't find the recommended ones.

I want to buy a 128GB one to avoid having to take it out more times. Any one should work, but since it is not the case....

If someone else dares to put on the ones that have tried and work well, they give me more options.

 

[Haydn]

Thanks Pat.
Re storage cards..
I use 32GB one per job.
Less likely that you lose everything.
When I list my H520 I lost 24GB of videos I hadn't moved to my iPad pro.....
If that was a 128GB card. It would have been even worse.
For the price of 32 or 64 I would get multiple instead.... My 2c

 

[arruntus]

Thanks Pat.
Re storage cards..
I use 32GB one per job.
Less likely that you lose everything.
When I list my H520 I lost 24GB of videos I hadn't moved to my iPad pro.....
If that was a 128GB card. It would have been even worse.
For the price of 32 or 64 I would get multiple instead.... My 2c

I think just the opposite

Do you remember the brand and model of the 128GB card that worked for you?

 

[rdonson]

I'm also a photographer who's been using circular polarizers for several decades. Here's a more detailed video on what polarizers are fully about.

IMHO even if you can't always rotate a CP on a UAV it can still provide good results when the sun is high in the sky.

The one thing that seems to be missing for UAV photography/video is decent lens hoods.

 

[arruntus]

Very good video, he explains it very well.

When in a flight you have to make only one shot you can adjust the filter without any problem and get very good results. But when a series of shots are planned, it is normal to take them all in succession without landing between each to adjust the filter. The big disadvantage we have with the short battery life makes it impractical. If we have lots of batteries and the job requires it no problem, you can land as many times as necessary and this would be ideal.

Lens hoods for cameras that are normally mounted on a drone, but not very high level, are a problem to find. This is the last one I got, printed in 3D. The only solution I could find.

 

[Rubik]

[QUOTE="rdonson, post: 112814, member: 10662"

The one thing that seems to be missing for UAV photography/video is decent lens hoods.

[/QUOTE]
Here's a lens hood I made for the CGO3+ PolarPro ND16 filter (the one I usually use in bright sunlight). It's cut out of a Sprite can and epoxy bonded to the filter. The shape was determined experimentally by checking the 16x9 view and trimming until the hood was out of the view. It works surprisingly well.

 

[arruntus]

I take my hat off, good job, you've outdone me by far

ummmmmmmm Yuneec a lens hook, with mount as a filter?

I'll send you Sprite cans if necessary

Including them with the cameras would be a detail

 

[Rubik]

I take my hat off, good job, you've outdone me by far

ummmmmmmm Yuneec a lens hook, with mount as a filter?

I'll send you Sprite cans if necessary

Including them with the cameras would be a detail

Thanks.
My buddy has a desktop 3D printer and has offered to make a prettier plastic lens hood for me but I doubt that it would be any better or lighter than the one I have.
Also, since I trimmed the hood for 16x9 images, it does show up in the corners of 4x3 photos. Not a problem since I usually trim photos to 16x9 anyway.

 

[arruntus]

Thanks.
My buddy has a desktop 3D printer and has offered to make a prettier plastic lens hood for me but I doubt that it would be any better or lighter than the one I have.
Also, since I trimmed the hood for 16x9 images, it does show up in the corners of 4x3 photos. Not a problem since I usually trim photos to 16x9 anyway.

My 3D printer is on the way, after canceling 2 previous orders and waiting a total of 2 months, with any luck I'll have it soon. Designing a lens hook for the E90 that allows filters to be used, I imagine that pressurized can be an interesting option. Weight can be a serious problem yes, even your choice is the most successful. The one that I showed in the other post was designed by me and certainly has a little weight, with my own printer I can do multiple tests and retouching to have something decent. Another thing for the list.......

 

[PatR]

The one thing that seems to be missing for UAV photography/video is decent lens hoods.

And depth of field...

 

[rdonson]

And depth of field...

Absolutely! If I look at the latest DJI announcements on new cameras and interchangeable lenses these are really BIG improvements for photography and video for UAVs. I hope it represents a new, serious trend.