Serious problem with video when using non-kit lens & dumb adapter..

[Francisco Estrada]

Hello, long time lurker here and I have a serious problem.

Basically when I use a dumb adapter with a canon 50mm f1.8 lens or the tamron 24-70 f2.8 on my NEX EA50 I get these ugly horizontal strips moving vertically across the video. Below is my video that way you can see what I am talking about..(please excuse my bachelor apartment...)

I discovered later that at 0 DB they completely disappear but at 21 DB it gets really really bad.... They tend to show up more or are more noticable against a white background.

This has never happened with the kit lens but happens almost every time I use the dumb adapator plus non E Mount lens it seems...

This really sucks for me cause I really wanted to move into using other lenses besides the kit lens... and I also need to be able to shoot at 21DB since most receptions are dark and what not..

I've search the internet and haven't found any answers... Is this normal or did I get a defect? Need some advise.. I have a feeling that if I talk to sony they will say something like "sorry but we don't support non sony brand lenses" or give me some stupid answer..

Thanks,

https://www.youtube.com/watch?v=rlcV...ature=youtu.be

[Chris Harding]

Hi Francisco

Now that's strange! Ok maybe some extra details might help here? What mode are you using on the camera 24P, 30P etc etc I saw the bands don't seem to appear on the soda can but more on wide shots?

What shutter speed are you using? Try allowing the camera to do the exposure for you. Put it into full auto and then just shoot and adjust focus manually only and let the camera choose the shutter speed.

Anything extra might also help to solve it too ...Does it happen in daylight too or just at night ..Did you have a flouro light on in the apartment maybe ... the bands might be the lighting so try a brief session in daylight too.

I have shot many hours of footage with the Tamron 17-50 and never had an issue ..Mine is a Nikon mount and I use a Novoflex adapter .... Is the adapter a decent fit ...some real cheap ones let light in!!

Give us as much info as you can so someone can maybe pinpoint the problem??

Chris

[Marlon Martins]

try reset camera settings and putting everything in manual...

im also using dumb adapter with 50mm f1.8 and 18-35 f1.8 and works perfectly, at any ISO (i use ISO)

[Chris Harding]

Hi Marlon

To me it looks like shutter strobing under flouro lights .. I know the FS100 gets it sometimes ... Must admit I have used a variety of lenses and never had it.

I would suspect he is shooting in 24P here and that's causing the issue with the shutter speed and light frequency ... Watch the fan spin ..looks like 24P to me

Chris

[Marlon Martins]

Chris, you are right, for now, looks like the only reasonable answer... he must set the cam to auto, and as he pushes the gain, the camera push the shutter, so higher shutters = higher flickering.

this need to be tested on daylight, post camera settings, etc...

[Noa Put]

If the non sony lenses display this problem, then the stocklens should show this problem as well, I would be surprised if that wouldn't be the case. To me this also looks like a wrong shutter, something you only can avoid but having that on manual and then choose the appropriate shutter to remove the flicker.

[Marlon Martins]

but the sony lens can close the iris to compensate for too much light, the dumb adapter not. so the only option is to increase shutter.

[Noa Put]

Yes, but that is something you would do manually on the non sony lenses instead (the iris adjustment) so the effect should be the same if the shutter is not fixed?

[Marlon Martins]

i believe all canon lenses do not have iris control on the lens itself, only in-camera (maybe older ones perhaps). as the adapter is "dumb", there's no iris control, from camera or user. so, it is f1.8 always.

some do a "trick" to lock lens in a fixed iris value: put the lens in a DSLR, set iris, push A-DEPTH button (closes the iris to the actual value set) and remove the lens while the button is pressed. the lens will have the iris "frozen" on the set value, so you can use it on dumb adapter at that value (like a f1.8 at f2.8)

[Steven Digges]

Francisco,

Are you plugged into wall power when that happens? If so try batteries and see if it is still there. Please let us know.

Steve

[Francisco Estrada]

Ok I think I got this under control.

With the wider lens + high gain/iso the camera would go into a higher shutter speed thus... High Shutter speed + fluorescent lights = ugly horizontal lines (especally the tube fluor ligthe). At least thats what I've notice so far. I am still going to do more test.

Chris ok I put the camera on auto and that did solve the issue. It seems that I need to keep my shutter under 1/250 shutter or so around fluorescent lights.

I shoot at 60P all the time but during my test those ugly lines were coming out at 24P, 60i as well... I was able to reproduce those lines with the kit lens by going high shutter so this wasn't an issue with dumb adapter/lens. Also regular incandesent lights weren't causing this lines nearly as much. Daylight/out door light wasn't causing this whatsoever..


I still feel like I need to be very cautious being that most venues use fluoresent lights.

I am willign to bet anyone here with a NEX EA50 can produce those lines if they shoot directly at a tube fluoresent tube light with high Shutter. Can someone confirm?

Thank you so much guys. Now I can move into the world of manual focus and larger aperture lenses. I was truely amazing the video a f2.8 lens produces compared to the kit lens but when I saw those lines I felt really bummed out. If I feel brave I might just use my tammy lens tomorrow for a event.

[Chris Harding]

I figured as much and I don't think it will be an issue at any event unless you physically zoom right into the flouro tube.

Even with a prime F1.4 lens in any normal venue you are unlikely to get any sort of high shutter. More often than not it will be sitting at 1/50th/1/60th and not move from there, I tried one of my EA-50's in our kitchen yesterday with the strip lighting on and a Nikon 35mm F1.8 lens on the camera full open and without pointing it at the light of course, the best I could manage to get the shutter up to in auto was 1/100th so no issue there.

Go ahead and shoot the event and enjoy your camera

Chris

[Noa Put]

You will always get these type of lines if you use a wrong shutter under specific type of light, it doesn't have much to do with a high shutter, higher shutter can intensify the problem but even at low shutter it can be there, that's why you should always control your shutter manual to get rid of the problem. I have read that fluorescent lights cycle on and off constantly at a fixed rate which can deviate on cheaper lights, so you should match that rate with your shutter to remove banding, I have had situations where this would be 1/40, 1/50 of 160th of a shutter. It also happened that whatever shutter I choose, I couldn't get rid of it completely, some camera's have synchro scan or also called clear scan by Sony which allows you to dial in much finer shutter increments to remove flicker or banding. Not sure but I don't think the nex-ea50 has this feature.