Hi! I am new to working with a Dslr. I've already tried dragonframe with my hd webcam last year, but working with a DSLR on Dragonframe is kinda tricky for me.
I just tried testing some shots with my 1100D in Dragonframe. Everything was set to manual, and I was using my Nikkor 50mm lens. When I tried taking a few shots just to make a test, I noticed when I played back the frames, there was like a wavey thing going vertically down, something that we usually see in the old crt monitors and old TVs. It doesn't look normal. Is there a way to avoid this thing?
I don't know that much about the Cinematography settings in Dragonframe. What are the things there that I must tweak or change. Thanks!
Never seen that. Is it on the final images as well as on the video live view? What was your shutter speed?
I know there can be some weird stuff when doing a fast pan in HD video mode, because as the vertical shutter moves, the image is exposed line by line starting at the top and working it's way down. So by the time the shutter exposes the bottom, the camera (or moving object) has moved a bit.
But that doesn't happen with still photos where nothing is really moving. Which is what you are normally doing with stop motion.
There's nothing about the lens that could do that, it is just set at a certain aperture and stays there.
Yeah, I can't understand what in the world it is. Any way you could post a clip of it on youtube or something?
That's your problem! Shutter speed is way too fast, and is phasing with the flicker from the lights (which would be around 50/sec. You need to slow down the shutter speed, not go faster.
Nick suggested to me to use a shutter speed of about 1 sec, which I am now doing, to smooth out any flicker from lights going infinitesimally up and down. This means using an aperture stopped right down to f16 or f22, and even using ND filters so it doesn't over-expose, 'cos you also need to keep the ISO at 100 or so.
I imagine the bar going across your screen is a bit like when they used to shoot film of a TV screen, and bars travelled down the screen... in pre-digital days! It was due to 24 fps clashing with 25 fps.
^ Yeah, that sounds quite likely. 1/50 sec is too fast of a shutter speed.
I looked at the older clip you posted and what you've got there is standard flicker, could also be from a too-fast shutter speed, but there are several other possible culprits, including letting the camera auto-control anything like exposure or white balance (actually it doesn't look like an auto white balance issue though, more like exposure).
Thanks Strider, Simon and Nick! Sorry for the delayed reply. I've been busy lately. So now I guess I fixed the issues.
Simon- You got it right! It's something like taking a video of a tv screen. But I just noticed the issue was a bit more on flicker. I tried making the shutter speed slower, and it finally worked! No more line things! But there was still a bit of flicker though. Anyway reducing the shutter speed helped! Thanks!
Strider- Actually my shutter speed wasn't only 1/50. Sorry I guess I overlooked the shutter speed in the camera. It was 1/125 so it was really fast. And Thanks! I discovered that my camera was on auto-exposure and auto-white balance! So I changed everything to manual. And tada! No more flicker! That helped. Thank you very much! Sorry I did not know that much yet about cameras. I just started. Thanks once again!
Nick- I use a fluorecent light. I changed the shutter speed to 1 sec. And it was perfect! Thanks very much! I just have a question, I guess I would go for the nd filter. Which one would you recommend, the screw-on type or the square slot type? I found this set of nd filters and I think it might be good, but still I would like to make sure if I need it.
Thank you guys! The flicker is all gone. I just want to know how can I shoot in Dragonframe on HD? I tried going to camera settings (ctrl+k) but can't see any option to change the resolution. Or should I need to crop/edit it in a software like photoshop? Thank you!
If you do a search for grip gear you might be able to find a photography supplier that sells the gels Nick is talking about - they're just simple tinted plastic sheets, heatproof so they won't melt or burst into flames, but you still want to keep them several inches away from your lights for safety. Brand names I know of are Lee and Rosco, there may be more but those are all I've seen available here in the US. Specifically they're called neutral density gels or filters, and they're sold in degrees of density (darkness), known as stops (f stops). You don't need to worry about exactly what f stop you need - what I did was just to get a very light one and a medium one, and I think one somewhere in between. You can layer them to get in-betweens, so for instance if one layer of very light density wasn't enough but the medium was too much, then I could cut 2 squares from the light sheet and layer them together. They're pretty big sheets, so you can cut quite a few pieces from each one.
I went down the route of ND filters on the camera, which reduce the overall light input evenly, but don't allow individual control of each light. It has been working well, as I can set the shutter speed really slow and still stop down to get depth of field.
But I can see why the experts would go for gels on the lights instead of the camera. Back to eBay, then! I might end up using both.
BTW I got some very useful blackwrap, (black coloured aluminium foil) for making into temporary barn doors etc. And it looks quite useful for stiffening hat edges and fabrics.
Hi! Sorry again for the late reply. I tend to sometimes be very busy that I forget to visit the site and reply. Sorry guys.
@Nick Thanks Nick! I now get what you're saying. I see those density gels in bookstores and school supplies stores. Just to confirm, are they like the ones used for x-rays in hospitals? Thanks!
@Strider Thanks for the terms! I made a search for grip gear on ebay and I found some. They were quite cheap. But I tried making a search of "neutral density gels" or "density gels" and there were even more! Thanks by the way! I guess I need to buy them for my lighting.
@Simon Thanks! I'll take a try for the filters but I think it would be more effective to use the gels, so anyway I'll still try your suggestion. Thanks. That's a great idea! Using the blackwrap for stiffening hat edges and fabrics. It may be effective to avoid the "boiling" issue of clothes in stopmotion. (I heard of that "boiling" term in clothes from Ohlson Animation :) )