Parts of my image are doubling (Urgent)

Cory Braun

Cory Braun

Well-known member
I was on a shoot this morning and ran into a problem when I switched to my 50mm Nikon f/1.8 lens. A duplication of certain parts of my image were visible. It was very faint and at first I thought it might have been lens flare but when I looked closer it was my actors tie/chest showing up. It was definitely a duplication of my actor because as he would move the duplication would move. It only showed up with my 50mm lens and I have used it with my GH1 before with no problem.

I also had an ND9 and ND3 on there so I took off the ND3, thinking maybe that was the problem (doubling up ND filters) but it was still there (and doubling up my ND filters worked fine for my other lenses).

I didn't record any of those shots so I can't post footage or stills but I am wondering if anyone else has experienced this and knows what can be done to fix it. It wasn't the angle I was at either, because I switched to the kit lens and did a very similar shot and had no problems. I am shooting again tomorrow morning so if anyone can help, I'd greatly appreciate it.

Thanks,

Cory

Update (in case you don't feel like reading through the entire thread):

I thought I had figured out the problem, in that it was my UV filter. I was filming a few weeks ago and with the filter on the overexposed areas would be doubled and when I'd take it off there would be no problem.

However, I was filming again this weekend, and noticed the problem again without the UV filter on. I thought maybe it was my ND filters. I took them off and I still had the problem. I then put on a different lens, 100mm, and noticed the problem again with and without filters on it.

Now that it has happened with two different lenses, 50mm & 100mm (both Nikons), I feel like it may be a problem with my GH1. The thing is, it still hasn't shown up on my 200mm or the kit lens. I thought maybe my Nikon adapter wasn't on correctly or that the lenses were not on the adapter correctly, but removing both and putting them back on did not help.

Anyone have any similar issues or any suggestions to what I could do to solve this problem?
 
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Barry_Green said:
The GH1 occasionally "ghosts" on the LCD. Doesn't affect the footage at all. This is probably what you saw.
Click to expand...

Would this effect the viewfinder as well? It was happening their as well. I saw the other thread about ghosting but I didnt think that's what it was because it was only happening with my 50mm lens.

Thanks for the help Barry, I appreciate it.

(I appologize for any spelling errors or typos, this was typed from my iPhone).
 
So I thought it went away today, because I did not see it while filming, but looking at my footage it is still definitely there. Here's a still of it.

imagedoubling.jpg


It's right next to his left shoulder and armer (screen right). If you look directly under his chin you should see it. You can see his arm and shoulder are very faintly doubled up. I am guessing this is a problem with my lens as it didn't happen with any other lenses, however it never happened before with this lens either.
 
Looks like the codec might not be keeping up...I've noticed blocky outlines on people in certain shots with high detail backgrounds thanks to the codec...but it is pretty rare.
 
Well, that's why I asked if you were using MJPG mode -- that's the kind of thing that happens with low-bitrate JPG compression. That shouldn't be happening on AVCHD mode.
 
From the small amout of motion blur I guess neither the guy or the camera is moving very fast. Ghosting due to encoding error should match his position on the previous frame. If it's a constant offset distance then something else wrong. Take a still with a similar situation and see if it happens. If it does, it's a reflection within the lens or on the inside of the filter.
 
Didn't look like ghosting to me, looks like mosquito noise on a high-contrast edge, which is why I thought it was probably the MJPG mode.
 
Wow, that's pretty awful. Yes, definitely worth discussing; a cheap non-coated ND or UV filter could cause reflections and flares.
 
Barry_Green said:
Didn't look like ghosting to me, looks like mosquito noise on a high-contrast edge, which is why I thought it was probably the MJPG mode.
Click to expand...

Agreed on the mosquito just along the edge of the t-shirt but I though Cory meant the ghosting that's visible in the dark areas of the foliage a bit off from the body. Allow me to do some CSI-style enhancements.
 

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Barry_Green said:
Wow, that's pretty awful. Yes, definitely worth discussing; a cheap non-coated ND or UV filter could cause reflections and flares.
Click to expand...

Yep,

it was a filter from India which I sent back and got refunded for.
A few days ago I recieved an email from them asking if I wanted to test their new nd filters, since they stopped selling the old ones after my complaint. That´s a good thing and I will test, of course...
 
JackBayer said:
Yep,

it was a filter from India which I sent back and got refunded for.
A few days ago I recieved an email from them asking if I wanted to test their new nd filters, since they stopped selling the old ones after my complaint. That´s a good thing and I will test, of course...
Click to expand...


Hello Jack,

Can you please pass on the link to their site. I'm interested in knowing who makes filters and such stuff in India.

Thanks.
 
Here's some video showing more of it. Look screen right to the man clapping and you will see a double of his hands clapping.

http://www.corybraun.com/imagedoublingvideo.htm

(Is there a way to encode video from non vimeo/youtube sites?)

JackBayer said:
Did you test for your problem without any ndfilter on?
Because it reminds me of when I once used a cheapo nd filter and got this as a result:
http://www.frontside.de/dls/ndfilter.html
Click to expand...

I can't remember if I tested it without the ND filter on, but I did use the same ND filters on other lenses with no problems. In fact I used the same exact step up rings, etc. with my 28mm with no problems.

Martti Ekstrand said:
Agreed on the mosquito just along the edge of the t-shirt but I though Cory meant the ghosting that's visible in the dark areas of the foliage a bit off from the body. Allow me to do some CSI-style enhancements.
Click to expand...

Yes, that is what I was referring to. Thank you for the photoshopping, I am currently without photoshop so I couldn't clearly point out what I was talking about. However, I think in the video shows much more clearly what the problem is.
 
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I get the same thing if I point my camera at a bright spot, it reflects back onto one of the pieces of glass. Only happens when I use my fader ND.

GH1
Nikon Adapter
50mm lens
Fader ND

That's when I get this problem. I've been thinking of buying an ND set just so this wouldn't happen.
 
Hmmm...never noticed that with my Fader ND or even thought about looking for it before viewing your example. So I tried reproducing your results and nothing. But then I took a double dose of Ferretor and, sure enough, there it was.
 
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