Short Division

Using the Canon 50mm f/1.8 with DSLRs

admin — Thu, 12 Jan 2012 05:35:00 +0000

If you have a Canon 5d Mark II, then you probably already have a 50mm lens that you use frequently. If you instead have a DSLR with an ASP-C instead of a full frame sensor (like the Canon t3i or 7D), you may be unsure about getting one. The Canon 50mm f/1.8 is very affordable for it’s speed (compare to the 35mm f/2.0 at $376), but with the 1.6x crop factor on ASP-C cameras, it’s actually an 80mm lens, not a 50mm.

I’ve been using the 18-55mm kit lens on my Canon t3i for about a year, but finally decided to buy the 50mm f/1.8. After using it for a few weeks, here are the pros and cons I’ve seen as of yet.

Pros

Bokeh for your buck – if you want to crush your backgrounds into pretty little circles, you can’t do it cheaper than this.
Low light – wide open, it performs beautifully in low light. You can easily shoot at night with just a few street lamps. If you do most of your shooting after dark (due to working during the day), even inside with lights, it’s an incredible improvement.
Smooth focus for video – the only thing I have to compare this to is the 18-55mm kit lens, but there’s much less jitter when you’re trying to change focus in a shot. Also, the focus ring stays in one place, no moving in and out, which makes focusing a little easier, and means you could attach a follow focus.

Cons

It’s a telephoto lens – that given, it’s been pretty usable as a general purpose lens so far. If you already enjoy shooting closer to the 55mm end of your 600D kit lens, then you probably won’t have a problem with it. You will have to move back further (1.5ft at minimum), which could introduce more shake, so keep that in mind.
Difficult to keep in focus – when shooting with the aperture wide open, very little is in focus at any given time. So if you or your subjects are moving, it’s quite a task to keep them sharp, especially if you don’t have a follow focus (which I don’t). Also keep in mind that you simply can’t focus on anything closer than 1.5ft/0.45m. Magic Lantern has some great features to assist with focus (peaking and magnification – during recording), so you’ll definitely want to look into those.

All in all, my opinion is that for the money and the aperture, it’s worth buying as a second lens. I’ll try to keep this post updated as I shoot with it, and maybe discover more pros and cons.

I put together a quick test video using the 50mm with my Canon t3i – as you can see, it’s difficult to keep in focus. I had it set to f/1.8, at night, with just a few street lights.

Flight Control

admin — Sun, 06 Nov 2011 19:57:42 +0000

Be sure to stick around for the effects breakdown at the end.

Audio Crossfades using L-Cuts in Final Cut Pro X

admin — Thu, 18 Aug 2011 04:58:14 +0000

Until recently, I’ve been doing audio crossfades in FCPX by detaching the audio of one track, dragging it under the next clip, and fading each audio track. This works pretty well, but since the audio is detached, it can get out of sync. Turns out there a better way, using L-Cuts and J-Cuts. I’m sure most people already know about these, but if you don’t, I made a graphic explaining how to use them in FCPX.

Double click on the audio track of one clip
It drops down – notice it’s still attached to the clip
Drag the audio clip under the other clip
Fade the audio on both clips – you now have a nice crossfade
If you like, you can double clip on the audio track again to collapse it back, keeping the crossfade/L-Cut intact

It’s fun and simple!

One more audio tip – right click on the audio fader to change the type of fade (linear, s-curve, +3db and -3db).

Credit to John August’s post on Final Cut Pro X which had a reference to using J-cuts and L-cuts instead of detaching audio. They were also mentioned in this helpful video about FCPX.

PFHoe 3D Tracking Tips and Tricks

admin — Wed, 10 Aug 2011 03:32:25 +0000

I’ve been doing a lot of 3d tracking using the Pixel Farm’s PFHoe - it’s fantastic for the price ($99, or $199 for Pro), but it’s a limited version of its more $840 cousin, and you do start to notice those limitations. So here’s a few tips that might help my fellow low budget match movers.

Check out the manual – I’m not used to software having manuals (seems to be a video thing) – turns out you really need to read this one. It’s hard to find some features without it.
Know about the keyboard shortcuts – if you don’t read the manual, however, know that the spacebar brings up a secret menu in most steps, holding option while dragging zooms the viewport, and holding shift while dragging pans it.
You do need to mask out moving objects – while it doesn’t have a built in way to make masks (I’ve been using Motion 5 – $50), not adding them really messes up the track.
Keep some sort of cube in the shot – since PFHoe doesn’t allow you to set the focal length, you’ll need to estimate it using a cube (it also helps with estimating the ground plane). If you’re doing tracking on a green screen, you’ll want to put a box on it somewhere, or a box with a box on top if the floor isn’t in the shot. I ended up taping several together and covering it in tracking markers.
If you’re tracking with a green screen – you’ll need to put tracking markers on it, and you’ll need to have something in the shot to demonstrate parallax, like a mic stand. There’s a really great 25 minute tutorial on placing tracking markers on the samples page for this course (it’s the second one down).
If you’re shooting with a DSLR – don’t keep your apature wide open if you have tracking markers setup, you want them all to be in focus at once. You’ll also want to have you shutter speed higher than normal, probably at least 100 to reduce motion blur (also mentioned in this video).
Check your start frames – if you’re noticing slippage in your 3d software you didn’t notice in PFHoe, make sure that the footage in your 3d program (if you have a video background on your camera for example) has the same start frame as the tracking data you imported. This is especially a problem in Blender.
If you use Blender – know that it doesn’t work in the latest version, 2.5. It does, however, work in Blender 2.49, which means you import it into that version, save project, and then open it in the new version. It’s a pain. I’ve started developing a script that would let you import directly from 2.5, but haven’t been able to get some of the left-right handed conversion to work (so take a look if you’re good with python and math).

Also speaking of Blender, libmv is currently being integrated thanks to Google Summer of Code. So we’ll have open source match moving right inside Blender (you can check it out on the tomato branch). Seems to work pretty well so far, should be interesting to see how it compares to PFHoe.

My wife with our tracking marker setup.

Feel free to comment with your own tips!

How to Boil Water

admin — Mon, 28 Mar 2011 04:21:34 +0000

In case you didn’t know (many people do not).

Watch How I Soar

admin — Fri, 25 Mar 2011 03:49:46 +0000

Bit of fan art.

Some Birds

admin — Thu, 10 Mar 2011 03:33:56 +0000

3x digital zoom on the Canon t3i (with the kit lens) – outside the CVS in downtown Freeport.

I think the bird in that second shot didn’t like me.

Cheap Sliders for DSLRs

admin — Tue, 08 Mar 2011 05:41:53 +0000

Cheap-ish, that is. I’ve been looking at sliders for fun (you’d think I could find something better for recreation), and thought I’d make a collection of the more reasonable ($100-$1000 range) sliders on the market. Jump over to the full post to see them categorized by manual, crank, and motorized sliders.

Manual Sliders

These are generally the cheapest. They don’t have a crank to move the camera, so you slide it along manually.

IndiSlider Mini
$99-$169 – 24″ (.6m)
No Drag Control
Issues: Can wobble forwards and backwards, but there’s an simple work around, move the slider instead of the camera, and apply forward pressure.

–

Kessler Pocket Dolly Basic
$499 – 38″ (~.9m)
No Drag Control

–

Crank Sliders

Instead of sliding these along the track manually, there’s a crank at the end. I’m guessing this would help keeping the motion smooth. Some have drag settings to help slow it down.

DitoGear CrankSlider
$983-$2,525 – 39″ (1m – available up to 2m)
Crank – Drag Control

–

Kessler Pocket Dolly
$629 – 38.5″ (~.9m)
No Drag Control

–

Kessler Philip Bloom Pocket Dolly
$1,095 – 41″ (1m – available as short as .7m)
Drag Control

–

Motorized Sliders

These are beautiful, but expensive. You can control and reproduce motion on these sliders via a remote. This is useful for compositing multiple shots, one on a green screen, and one as the background. Where they really shine, however, is with moving timelapses.

Dynamic Perception Stage Zero Dolly
$895 (the $447 price is a 50% pre-order) 72″ (~1.8m)
Issues: this is a kit, it doesn’t come assembled, but apparently it’s pretty easy. The controller doesn’t look quite as nice as the DittoGear model.

–

DitoGear OmniSlider
$1,894-$2,525 – 39″ (1m – available up to 2.5m)

–

Summary

Although I’d like to get one of the motorized sliders on of these days, my wife seems to think the $2k could be better spend upgrading our furniture collection (I know, it surprised me too!). And considering I only really need one of these for doing smooth shots outdoors (I have a normal dolly that works great on smooth surfaces), I’ll probably end up getting the IndieSlider Mini.

Canon t3i

admin — Wed, 02 Mar 2011 06:01:26 +0000

I did a post last month comparing the Canon 60D and the Panasonic GH2 – the two specific models of cameras we were trying to decide between at the time. Not too long after, Canon announced the successor to the t2i, the t3i (or 600D), which we ended up buying. It arrived today, and we’re very happy with the way it’s working so far.

So I thought I’d post some of the reasons we decided to go with it over the 60D/GH2.

The reasons we decided to go with it instead of the Panasonic GH2 –

Lenses – the GH2 uses the m43 lens format, which is relatively new. It’s still somewhat difficult to find good, cheaper lenses for it, and while the number of options are growing, I decided I’d prefer to build a collection of Canon lenses. I’m hoping that ends up being a good choice, and that Canon follows Panasonic’s lead in making video a priority. Guess we’ll see.
Canon Software – this isn’t a particularly good reason, since the software that comes with Canon cameras isn’t that great. We did want to have the ability to do remote shooting from a laptop, and use the Picture Style Editor.

The reasons we decided to go with it instead of the Canon 60D –

3-10x video zoom mode – the jury is still out on whether this will fix aliasing problems. I haven’t run into any aliasing problems yet, so I haven’t been able to test it, but hopefully it’ll act like the GH2 video crop mode.
Cheaper, but with similar features – body only, the t3i is $100 cheaper than the 60D. You can get the t3i with the kit lens for the same price as the 60D without a lens. They both have articulating screens, and there’s very little difference between them feature wise.

So that’s why we chose it over the other two. It’s working beautifully so far – at least it’s significantly better than the iPhone 4.

Using a Canon FD lens on an EF camera

admin — Tue, 01 Mar 2011 00:41:02 +0000

My family gave us an older film camera (a Canon FTb, thanks guys!), for the 50mm f/1.8 FD lens, which we were hoping to use on our new Canon t3i (more on that soon) instead of purchasing a Canon EF 50mm f/1.8 II ($119). The issue is, of course, that Canon cameras made after 1987 use the EF/EF-S mount, which means you need an adapter to use an FD lens with it. These FD to EF adapters sell for about $30 on Amazon, not terribly cheap, but less than the cost of a new lens.

The problem is the adapters aren’t seamless – there are two kinds, the ones with optics, and the ones without optics. The ones with optics loose a full stop of light – so an f/1.8 lens will become an f/2.8 lens – not very appealing. The ones without optics, you don’t loose any light, but you do loose the ability to do infinity focus (∞), so you’re not going to be able to focus on distant objects. Apparently the flange depths make it impossible to get the lens distance correct with an adapter.

So if you’ve got one of these lens, and don’t mind loosing a stop of light, or the ability to do infinity focus, then one of these adapters should work great. The general consensus, however, seems to be that buying a new EF/EF-S lens may be better.