Canon EOS + Nikon dragonframe combo... Im talking about the "flickering"

Just a quick question.
I'm just starting out on this stop-motion journey (after a 25 year break, I should say, used to be a Bolex 16mm guy in the 80s).
Now I'm not too up to date, and not willing to pay out straight away for a super dooper expensive cam, just yet. So initial experiments will have to be with my cheap n cheerful Canon 1300D.
Now I will be shooting very small, not quite macro, but want to get a macro lens. I have the chance to snap up a simple Canon EF50mm f2,5 lense locally.. but then I noticed the note on the Dragonframe site regarding using an adaptor + Nikon lens to avoid the "flicker".

So my question is, how obvious IS this flicker.-.. should I not bother with this lens at all, and wait out to find a suitable (cheap) Nikon... (Whatever that is...? As I said...NooB) or will this one do for a start?

Thanks in advance.

MArk

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I find wearing black and using LED lights seems to do the trick. Then again, I am far from a perfectionist at this point. I use a old Nikon D50.

Maybe you are referring to a completely other issue ( I’m intrigued as to what wearing black and LED lighting has got to do with anything, I have slot to learn apparently) No I’m referring to the warnings Dragonframe refer to about using auto lene’s.
Here’s the quote:
“ Note that we strongly recommend using a manual aperture lens (such as a Nikon lens) with a Canon body. With a digital lens, the aperture will close down to slightly different positions for each shot. This is not a problem for still photography, but for stop motion or time-lapse it creates “flicker”. For Canon cameras, use a Nikon manual aperture lens with a Nikon to Canon lens adapter.”

Canon lenses have no aperture ring on the lens itself, so it is controlled electronically by the camera's tiny brain.  So the lens must remain in electric contact with the camera body.   But because it wants to be helpful and adjust exposure and other things to make the best still picture, it is not helpful for stop motion where you need everything to stay exactly the same.  For shooting stills, it is normal for the aperture to open up between shots so you get a nice bright view through the viewfinder, then as you press the shutter, it stops down and then takes the shot.  As the DF guys say, it does not stop down accurately enough for animation.  Nikon kit lenses are the same, no aperture control.  So the usual solution is to use an older Nikon manual lens, wth a simple adapter, so focus and aperture are set on the lens and the camera is unable to make changes.

I use a Canon 40d or 7d with adapters and an older Nikon 55mm macro lens for close up shots.  I also use a Nikon 28mm wide angle, and occasionally a 24mm, and very rarely an Olympus OM zoom lens with its own adapter.  All older lenses bought second hand, made for film cameras, so they will cover the full frame sensor as well as the smaller ones. Fortunately most other brands are designed to sit further out from the film plane/sensor than Canons, so the thickness of the adaptor actually makes them the right distance and there is no problem with focal distance.

There are other causes of flicker, some from the camera.   As you walk in front of the camera to move the puppet, the camera would want to adjust focus and exposure, then adjust back as you get out of the way.  3rd party manual lenses stop some of this, but there are other sneaky things to look for.  So as well as setting exposure on Manual, you have to go through all the menus and turn off anything that tries to adjust or compensate focus, white balance, exposure,  as you go.  Every model is different, I had my 40d sorted but then the newer 7d had a couple of new functions I didn't know about the first time I used it. I think one was called Edge Compensation.  Remember, the camera wants the best possible still photo each time, but an animator wants every frame to have the same settings.   

There is also light in the studio, so things like daylight leaking in which will change gradually in real time can look like sudden shifts when you take a frame every minute or two.  Shadows cast by the animator, or standing in front of the monitor while taking the shot (and the pointing towards the set) can cause flicker, because you won't be in exactly the same spot every time.  Or light reflecting off a white T-shirt can sometimes make a difference.

The other cause of the light changing in the studio is a variation in the AC mains power  - in my studio, by 1 or 2 volts - which again is gradual but in animation causes sudden changes.  Trying to compensate afterwards, the difference was only around 1%, but it is noticeable.  And because I had a mix of lights, where the halogens responded to voltage changes by getting brighter and darker, but also some fluorescent fill light which tended not to respond to small changes in voltage, some of my light changed but some did not.  So it could not be fixed with flicker-fixer software.  (Fluorescent lights mostly don't work with a dimmer, which is deliberately changing the voltage, they stay the same until the voltage drops too far, then start flashing or go out.)

I shot frames of a multimeter attached to the mains power, and I could see the lights got brighter when the needle went up, and dimmer when it went down.  Power was more stable between 1 AM and 5 AM, when factories in the neighbourhood were not turning machine on and off.  I could also make it happen for my test by switching my big oven (for foam latex baking) on and off.

Some people use a Variac, which controls the voltage, like  more precise dimmer and a dial so you can see what the output is.  You use it to reduce the voltage a bit, then check it every frame to keep the output to the lights at the same level.

I use an Eaton Powerware Double Conversion UPS, which converts AC power to DC, charges a battery, draws power from that, and converts back to AC.  It drops a couple of volts but keeps the power to my lights smooth and consistent without me having to do anything.  I had just had my studio built, and already had an electrician put in overhead lighting circuits with sockets in the ceiling and an 8 switch power board plus master switch, so my lights could plug in up there and not have cables trailing everywhere.  Then I found my new studio had flicker!  Disaster, I had spent all my money and it was useless.  Narrowed it down to the dirty AC Power.  So I had to get a unit that is hard wired in if I wanted to keep using those circuits, at around $5000 in Australia (Prob more like $2500 in the USA).  Much cheaper would be a portable plug-in 1500 VA unit, and with the low power lighting now in use, that would be more than ample.  And more convenient.  Wish I'd gone that way. 

If you can get lighting that does not respond to small voltage fluctuations, this might not be an issue.  I'm not sure about LED lighting, still using my old lights.  Maybe they fix the problem?  If they do not work with an ordinary dimmer, then there is a good chance they would not vary with minor voltage changes.

That Sir, was very illuminating... and comprehensive. Thank you so much for taking the time to write this!

I had a lot of problems with using tungsten lights and flicker, but have not had any since going over to LEDs. I think it may have been the high current draw of the tungsten lights being affected by things like the washing machine switching on and off. LEDs do not seem to suffer from this issue, except when being dimmed a long way down. This is due to the fact that the dimming is actually switching on and off at high frequency.

I have been looking out the high CRI LEDs, which give very good colour rendition. There are some bulbs with 95+ CRI, and I have been using LED strips with 85+. None of these are expensive. So I have some old PAR 16 cans with little barn doors, and have just put some LED GU10 bulbs into them. They work very nicely. I have also built my own LED panel lights with dimmers. All flicker issues seem to have gone! So if you are buying lights, that is the way to go.

On the lens issue, have a look at a good YouTube video called Vintage lenses for stop motion. It is here https://youtu.be/2TXMjalIJvE

So, if the LEDs need a special dimmer that works by changing the frequency of pulses, maybe that means just dropping the voltage a bit won't dim them. That would be worth me getting some LED GU10 bulbs and testing them.  I have 2 or 3 of those Par 16 cans made for halogen GU10s.  Also need to look for the 12 volt version, since another 5 of my lights are home-made with the transformer and light fitting from a downlight kit, and some barn doors cut from aluminium sheet.

I wonder if there is an LED replacement for the sealed beam reflector units in the 6 volt 30 watt pinspots I use for backlighting?  I tried a little LED pinspot, but it was much less bright, very purplish-blue, and had a sharply defined edge to the circle of light.  Good for moonlight but not much else.  This whole lighting area is changing quite quickly so I am overdue for some more research. 

The Nikon Ai-S AiS NIKKOR 55mm f/2.8 Micro MF Lens is amazing.  You can find them for around 100 USD on ebay, shipping from Japan.  The Nikon Ai-S line of lenses is fantastic. You just need a converter ring to use them on your Canon camera and you are good to go.

OK just bought one... Thanks for the tip!
I have an adaptor ring but weirdly it only fits a few of my Nikon lenses, so will have to see when this one arrives, but that shouldnt be aproblem, or expense really.

Adam Taylor said:

The Nikon Ai-S AiS NIKKOR 55mm f/2.8 Micro MF Lens is amazing.  You can find them for around 100 USD on ebay, shipping from Japan.  The Nikon Ai-S line of lenses is fantastic. You just need a converter ring to use them on your Canon camera and you are good to go.

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