Hi:

I'm returning to stop motion after a number of years in the digital world. My objective is primarily to do art pieces for my own enjoyment/exhibition, rather than commercial projects. That means that my budget is based on what I can take from the household money, so I'm trying to determine my options. 

I bought a Canon 70D a few months back with the AF-S kit lenses. My interest was basic photography and film projects, not necessarily stop motion work. However, since I've had it the option has come up, and so I'm exploring the necessary equipment and software. 

Having run tests with some demo software, I've become aware of the flicker which many people have mentioned. If I understand correctly, this is caused by the camera driving the iris down just before clicking the shutter, and that the iris is normally wide open during LiveView. As the crank-down is not exactly the same amount each time, this results in a noticeable shift in exposure when doing successive images. 

So, I understand the most correct fix is getting a manual aperture lens, along with a required adapter ring and shooting the old fashioned way. No problem, I shot film for years with manual systems, but there's the cost of the additional parts, plus the cost I'm already looking at in software, for what is essentially a "hobby" at present. 

So I had a couple questions for those more experienced before deciding to raid my change jar. 

First, is the aperture issue related to the use of the LiveView feed for the primary software systems? That is, does the iris sit open until the shutter button is pressed only when using LiveView or regardless of it. 

Second: Is there a reliable means that is safe for my equipment to disable auto aperture on the existing kit lenses I have?

I have heard about someone putting electrical tape on the contacts, and I hit upon using a cheap macro-tube with no contacts. That said, I understand that there's no manual setting for the aperture on these lenses.

I have seen some hacks suggesting that you can set the aperture, then press the DOF button to close down the iris and then disconnect the lens. My camera manual states to turn off the camera before connecting/disconnecting lenses, and I've tried to be very good about that. So if anyone has an idea of how that procedure works and if it runs the risk of damaging my equipment, I'd appreciate your insight. 

As a third alternative, what are your thoughts on using ND filters to compensate for the lack of aperture control? 

Finally: If you were putting together a kit of the manual lenses to shoot which focal lengths and settings would you recommend for a reasonable flexible kit. The 70D is 1.6 crop factor, and my biggest set will probably be about a meter wide by may two meters deep, by no more than a meter high. I expect most will be much smaller, but I'm going by the size of tables I have to build on. At this point I'm willing to look at either the Nikon or old Canon FD lenses, but as one adapter is cheaper than two, I'll probably pick one brand to stock. 

I appreciate any advice you are willing to give. I know far less about the cameras than some of the other parts of the process and need to learn. At the same time, I need to try and work out how much it's going to cost me and whether it makes more sense to just use a webcam and freeware at least until my skills build back up and my cashflow improves. Thanks in advance. 

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1.  Nothing to do with live view.  It is standard practice on DSLRs, and the SLR film cameras before them, to open up the iris for a nice bright view, and then stop down only when you press the shutter.  Movie cameras, like the 16mm Bolex or the 35mm Mitchell, did not do this, the aperture was stopped down and stayed there.  That way, the aperture did not vary between frames, which mattered with movie film, but not for still photos.  

The easiest way to fix this on a Canon is to use a fully manual lens and the simple kind of adapter with no electronic connections.   On my old Nikon D70, made before Live View even came out for DSLRs, I learned to not use the kit lens because it flickered, and to partly unscrew the manual Nikon lenses so the lever that opened them up could not make contact.

2.  The kit lenses, and all the Canon lenses now, do not even have an aperture ring on the lens.  So they depend on the camera controlling the aperture.  You do need to disable auto functions by going through the menu and turning off every auto function, but that will not in itself stop the lens opening up when it is fully connected.  

I believe there is a work-around, though.  You have to set the aperture you want, then partly unscrew the lens so it can't be controlled like I did on my Nikon...  I think it is what you are describing, but I'm not sure because I have never had to do this.  I had my Nikon lenses for my Nikon body before I got my Canon 40d, so I just used the Nikon lenses for animation.  I do have one Canon lens which I hardly ever use, so I will go and do some experimenting.  I'll get back to you on this.

3.  An ND filter will make the picture darker, but so will taking a shorter exposure. I mostly animate with long exposures, 1/2 sec up to 1 1/2 sec. so there is plenty of room for reducing the exposure time.   But it will not increase the depth of field like a smaller aperture does.  That is very handy for shooting on a miniature set, shallow focus is one thing that makes a scene look like a miniature.  (Hence those photos of real cities where the top and bottom have been blurred to make them look like a photo of a model railway set.)  Usually we want our small scale set to look more like a full size location.  So I don't see any point in getting the filters.

4.  I managed very well with a Nikkor 55mm micro and a 28mm wide angle. My 40d and 7d cameras have the same crop factor.  I later bought a 24mm from eBay in the US which is a bit wider, but was too expensive here in Australia for me to buy initially.  One or the other wide angle would do.

2 metres deep is quite deep, especially for a set only 1 metre wide.   I have had several sets that deep if you include the set table at 1.2m deep, plus an 800mm gap, before the painted backcloth on the wall - but the set was 2.4 metres wide, and the amount of visible backcloth more like 3.5 metres wide.  (cloth total 4.8M but you didn't see all of it in the one shot.)  I'd say to get the 24mm to get more depth of field and get more of that in focus (wider angles have greater depth of field, as well as smaller f-stops) but the wider the lens, the wider the area it sees at the back.  

I would turn that set around so it's 2 metres wide and 1 metre deep, probably.  

With a longer lens like the 55mm, the field of view doesn't spread out so much at the back, but the focus will be more shallow.  Good for a closeup of the puppet where you want the background to go out of focus to focus attention on the character, but not so good for simulating a wider view of the real world where everything is reasonably in focus.

As a cheap practice setup, I use StopMotion Studio on an iPad, which cost me nothing (above the cost of already having a tablet or smart phone) apart from making up a frame to hold the iPad onto a tripod.  You can buy those, and the ones for phones are cheap and easy to find.

Anyway I'll try that trick with the Canon lens and  the DOF button and see if it works.

Ok, I tested it, and it worked.

I fitted my Canon 18-55mm lens to the 40d, and set the aperture at f-16.  Pressed the DOF button, I could see it get darker in the viewfinder, released it, it got bright again.

Then I connected it to Dragonframe and pressed the DOF preview button, and the lens mount release button, and partly unscrewed the lens - mistake!  Don't do that while connected to Dragonframe!  DF put up a warning about loss of camera control, Camera froze, nothing worked.  I disconnected it from the computer and switched if off and on again 3 times, it still wouldn't do anything.  Unplugged the power, replugged and on again, no good.  Then I removed the power adapter from the battery compartment, replaced it, and turned the camera on again, but not connected to the computer, and finally it worked again.   

This time, I pressed the DOF button and partly unscrewed the lens so the camera was ready, and then connected the USB cable to the computer and Dragonframe, and that was good.  The video preview looked darker, as you'd expect.  I shot off 10 frames, and then looked at the full res images in Dragonframe, and they all looked good, the right exposure, and no flicker.

Then, just to compare,  I disconnected the USB cable, and screwed the lens in fully, so it was brightening up between shots like normal.  I connected to Dragonframe again.  The preview was much brighter.  The actual shot was very slightly brighter, but I shot off another 10 frames like that, and they stayed the same, I didn't actually get any flicker.  So did unscrewing it prevent flicker?  It ought to, but I didn't see flicker anyway, so it's inconclusive.  Maybe if I shot 100 frames I would see some.

So - try your lens, it may not actually flicker.  Some do, some don't.  Mine wasn't actually sold as  a kit lens, I bought it separately with the body so I would have at least one Canon lens for general purpose happy snaps, but it was only just over $100 so still a cheap lens. 

If your kit lens doesn't flicker, great!   If it does, the DOF button and unscrewing seems to work - but do that to the camera first, then connect the USB cable.

There are other reasons for flicker.  First, after setting the dial to M for Manual, check every setting in the camera menu.  Any kind of auto correction is a bad thing.  My 7d has a couple that the 40d didn't, and until I found them and disabled them, it flickered.  One is something to do with edge correction, to compensate for fall-off in brightness around the edges of an image, I forget what the other one is.  On the lens, set it to Manual Focus if it has a switch for that.

Then, the lights may actually vary in brightness, because the mains AC power supply might vary over time by a volt or two.  With animation, gradual changes over a couple of minutes can appear sudden, because you only took one or two frames during that time. That's what happened after I built my backyard studio - I discovered there was unsteady power in my locality.   Try non-dimmable compact fluoro lighting - they don't respond to small changes in voltage, until it drops so low that they go flickery or cut out altogether.  If you have a plug-in dimmer switch (like you can get from Ikea) you can test them.  

The other option is more expensive, it's a power conditioner that steadies the voltage. Try the fluoros first!  I have a Double-Conversion UPS to smooth out the power for most of my lights, but at the moment I am also leaving on the flourescent tubes on the ceiling which are my normal work lights, for some soft ambient light, and they don't go through that, they are unfiltered.  But being fluoros, they don't vary, so it works.  (But you do want exposures of at least a half second with fluoro lighting, because it has a rapid flicker of its own.  A longer exposure means it flickered a couple of hundred times during the exposure, so it evens out.)

Thank you. That was immensely helpful and right on the nose with what I needed. 

I may have a source for some of the Nikon lenses, so that would be the route I'll go if I can get them relatively cheap or borrow them. 

In my test shots, I actually only saw flicker in one long one yesterday, and that could have been due to lighting issues. Right now I am playing around with basic room light while I'm trying to figure out which software to purchase. May not be the best test, but since I saw a number of posts about needing manual lenses, I assumed that was the cause. 

I have a number of LED based lights and access to double conversion UPS units (my company sells them) so I will try some more controlled lighting in future tests. 

I also have the tablets and phones (Android, but I have stop motion software on them) and a tripod mount already from my other film making gigs. I will look into trying those as well, just hate to have good equipment and not use it. 

Thank you for the suggestion of turning my worktable sideways. As simple as that sounds it had not occurred to me. I had seen some stages in one of my books where they'd built forced perspective sets on a long axis, so that is what I was thinking about. Obviously, though, even with forced perspective the angle of view comes into play (forehead slap). 

I greatly appreciate your extensive answer. Hopefully I'll be able to return the favor some day. Cheers. 

That is a really great answer Nick and important topic to us that already have Canons for pictures of the family and such and want to use them for animation.

I used my 18-55 kit lens with my T1i (500D) and had flicker on my first animation. So I unscrewed the lens and was able to complete the project. The key to it working for me was first hitting the preview button on the front of the lens and holding it down, then pushing and holding teh lens release button while unscrewing the lens just barely. It worked but I would hate to do a big project like this. The software I was using (Videostudio) would not show the correct exposure and sometimes would be so dark I could hardly see it. I assume this is caused by not being able to read the lens.

In hindsight I should have tested two other lens that I have for the camera. I will not make any more films until I have a better solution. During testing I shot the exact same scene with no movement at different intervals. Not only can you see the frames getting brighter and darker during playback but you could also see it in the file size. So I grabbed two frames that had the biggest file difference and split them in half and put them side by side and teh exposure problem really stands out that way.

It's good to hear someone else's experience with a similar camera and lens. I ran a time-lapse test this morning. Even though it's still not under controlled lighting, it seems to indicate that the kit lenses will strobe due to the electronic iris. 

My chief concern here is disconnecting the contacts on the lens while the camera is powered on. Even though I presume the command signals are low voltage, it's still live and potentially could arc or overload one of the points.

I am guessing the aperture will not remain "locked down" once the power is cut, or am I wrong? 

Never considered it damaging the camera. I was more worried about unscrewing it too much and the lens falling off.

I think the iris does remain locked after power down. When I was finished for the day I would turn off the power strip and could continue shooting the next day with no touching the camera and it was like I never left. I could be wrong it was my first and only film to date.

I am pretty sure I will go the Canon FD lens and a mount. New in box lens for $80 and a mount for $25 will be worth it but wasn't an option a few months ago.

That's where I am evaluating right now. I've not done enough "money" shooting with my camera yet to start raiding the accounts for new glass. Plus the cost of software, and then the cost of armatures, sets, etc. Some of which I have, but there's always something. 

I'll check the 70D and see if the lens stays stopped after I shut off. 

It will stay put, as long as you're using the camera with the lens unscrewed partially or in some way disconnected electronically. It has to, because the lens itself can't move without the impulse from the camera. As soon as you break that electronic contact, it essentially becomes a fixed lens. 

Now if you're using it with the lens fully screwed in, then I imagine it will lose the focus setting when you power down. Because it's the camera that's 'holding' it to that setting electronically. Or rather continually bringing it back to that setting - it doesn't actually hold it. As long as you have an auto focus/ auto exposure lens attached to the camera so there's an electronic connection, it will open and close the iris for every shot. I don't remember if it closes it after each shot or opens it, or exactly why, but it does one or the other, and then returns it to your chosen setting, or 'close enough' for still photography anyway. Which of course doesn't need to be anywhere near as close as for animation, where even the slightest difference in exposure or focus from one shot to the next reads as flicker. If you're looking at individual still shots you can't really tell if there's just a slight difference between successive images. These cameras are designed and marketed for still photography after all, not specifically for animation. 

More good info. Thanks Strider.

I ran all kinds of tests. This image was part of a time lapse test that I ran to see if I could fix the issue in post. Here I compared the smallest and largest file sizes. The second image I compared two images that had the same file size and you can't even see the seam.

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