ND Filter Issue

[Ryan Sigler]

I have a Firecrest 1.5 ND Filter, and I have tried to use it several different times and did some testing today to see if I can get it dialed in. After putting the filter on and adjusting ISO & Aperature to a decent settting, the edges of my video are blurring. The video is blurring enough that I don't want to run the filter.

Has anyone else ran into this issue? Or can anyone Identify the issue? Everything is fine without the filter, so I'm assuming it's indeed the filter that is the problem. However before spending some cash on a new filter(s) I just wanted to see if anyone else has had this issue.

Thanks.

 

[SanCap]

Which lens are you using? What is the aperture/shutter speed you seem to be using the most?

 

[Ryan Sigler]

Which lens are you using? What is the aperture/shutter speed you seem to be using the most?

I am using the dji x5 lense the 1.7. I focused it in using 16 aperature and pretty much run that because it's hard to get it dark enough. Obviously with the filter I knocked down the aperature to as low as 5.6 because it was cloudy the day I tested my filter. I tried playing with the aperature and although it seemed to help when I took the aperature all the way closed to 16 it sharpened it up a bit but it still seems like in a circle around the edges of the frame is blurry.

When it's at 5.6 or so, it's blurry 40% of the way into my frame. I did order some Tiffen Filters because i want to rule out that it's the filters. I really think it's the lense with any aperature less than 16. I'm running 60 shutter speed almost all the time because I shoot at 30frames a second. What do you think? I usual run ISO as low as I can go 100 or 200 I forget what the lowest is since I haven't looked at in minute.

 

[SanCap]

The DJI 15mm lens is not known for its quality. You do want to keep the aperture to around f5.6 all the time. F16 will not do well for video on these cameras. If you can't do that you need a darker ND filter.

Quality ND filters are key and Tiffen are on the low end of the spectrum.

Can you share a video showing your issue?

What is your focusing procedure?

 

[Ryan Sigler]

I don't have a video of it off hand but the next time I do testing I will save the video. Thing is, I shoot with F16 all the time. It works great for me. Everything is sharp, my videos are good quality and have no complaints other that I could have better color. As soon as I added the Ficrest ND fillter, It gets blurry on the edges. My focus procedure is just to calibrate it. Putting it on F16, finding a contrast subject at least 50meters away and tap it, Usually several times until I feel it has focused correctly. Should I redo focus it with the filter on?

 

[SanCap]

Try this. Put the filter on, find your subject while flying, tap to focus and then turn the focus to manual. It will not hunt and change your focus. Once again f16 is not the sharpest aperture for these cameras. A sample will definitely help.

 

[Ryan Sigler]

I appreciate the info. I am going to do some testing in the next few days, with different filters and setting. I'm thinking about getting a pani 42.5mm lense as well.

 

[Ryan Sigler]

here are two photos showing the edge blur. This is with the firecrest IRND ND1.5 filter. F4.0, SS 60, ISO 800 or so. I focused a few times. The courthouse is in focus but the edges are blurry as hell. It is cloudy and a very light drizzle, but either way the edges are blurred. This is what I am experiencing in video and images. Edges are not blurred without the filter. So weird. I thought Firecrest was one of the better ones. Trying the Tiffens as soon as they arrive.

 

[SanCap]

If both of those are taken with the filter and you image is perfect without the filter than I would say your filter is the issue. Are those screen grabs from the video?

The Firecrest IRND are good filters, I have a couple that I have used in the past with no issues.

 

[Ryan Sigler]

no, those are the .jpg photos. I realize they are junk photos, but I was messing with focus and the settings so I'm sure it was off. Yeah, I know it's the filter because it has been nothing but junk since I have tried it. I am just now revisiting the issue as I run no filters at all and get a good image, it's just that I want to improve the image if I can.

Just didn't know if anyone has ever seen that much blur around the edges like that. Just in case I am missing a something. I will be back with revised info once I do a filter swap.

 

[Ryan Sigler]

New filters came in today and after some good indoor testing, I am 95% sure its the lense. The blur is there all the time, with or without filter and have figured out the amount of blur is directly effected by aperature. More wide open such as F2 is very blurry on the edges, more closed starting at f9 it is hardly noticeable. Just waiting on the 42.5 panisonic lense to arrive to see the difference. I may get a different 15mm or close to it as well if the 42.5 doesn't have the blur and proves that it is the lense.