Wednesday, September 23, 2009

HDR Aquisition - Gear

First before we get into gear, we need to decide how you want to take your panoramic HDRs.  You can shoot an panoramic HDR with just about any lens.  It just depends on how much time you have to devote to shooting your complete data set.

Generally the longer the lens the more angles you'll need to take a complete panorama.  And that will increase your final overall compiled image resolution.  The wider the lens the fewer angles you need to take for a complete set but then you will have lower resolution compared to shooting with a longer lens.  Final resolution also depends on your camera's Megapixel size.

There are lots of different types of setups for shooting HDR panoramic environments.  Below is my current setup, and I will also go over some of the alternative gear available.

Since we are talking about on set data acquisition my setup is geared towards speed.  Thus I am using a wide angle lens.  In addition I put a my 24-105mm lens and shoot a non spherical pano with the same system outline below.  This is good for background plates where resolution is the key.

My Gear for Shooting panoramic HDRs on Set.
I would consider this a solid DSLR HDR panoramic setup.  This setup has a full frame censor and the 8mm fisheye lens can shoot an entire panoramic environment with just 3 angles (120 degrees apart).

If you have a cropped censor you can still use the utilize this lens but you will need to shoot 4 angles (90 degrees apart).  Sigma also makes a 4.5 mm fisheye lens designed specifically for cropped sensor DSLRs.  They make a variety of mounts for this lens to fit cameras from Canon, Nikon, Pentax,  and Sony.  The 4.5 mm fisheye will allow you to shoot a full panoramic just like a Full Framed DSLR in just 3 angles.

With my current setup I can shoot a full panoramic HDR in about 2-4 minutes depending on the on set lighting conditions. 

There are few newer tools that will speed up this process.  One of them is the Promote Control System.  This device aims to increase the standard 3 images (+/- 2 EV) for Canon Cameras.  This system also works with Nikon cameras but some Nikon cameras have an advantage where their in camera auto bracketing takes up to 7-9 exposures.  The Canon 1Ds MkII/III is the only Canon camera the shoots an auto bracket sequence of more than 3 exposures.  It can shoots 7 (but who has $8k to spend on a camera!).

Check back as I will be reviewing the Promote Control system in the coming weeks.

Other Available HDR Panoramic Gear

If you have the deep pockets or your working on a big budget feature film you might want to check out some super custom imaging systems.  But if your pocket aren't overflowing with cash there is also some budget gear out there to get you started.
    • An all in one solution geared towards feature films.  This robust stem can be fired remotely meaning you can stick it in many places there it would be dangerous or impossible for a person to shoot an environment. (ex. on a Technocrane).  This system comes with a complete software package that will compile, log, and prep your HDR for import into Maya.  I believe this system is for rental only.
  • Spheron
    • The Spheron has been around a long time.  It's manufactured in Germany so it has to be good right?  This is a custom imaging system that shoots a full spherical HDR in one pass that has a dynamic range of 26 f-stops.  Like all systems I'm sure this one has a hefty price tag.  It also looks like Spheron has a service for capturing as well.. if you don't want to buy the system.
  • Panoscan
    • The Panoscan is another custom imaging system that has its optics designed for the camera from the ground up.  Some of this systems highlights (according to the website) a full scan takes 54 seconds.  Shoots in low light up to ISO 3200, Autowhite balance, accepts Mamiya, and Hasselblad lenses, and its unique magnetic slit cap improves image quality by blocking lens flares and reducing glare.  
    •  These guys demo their product for me a couple of year ago and it was very impressive and solidly designed.
  • Peace River
    • These guys make a ton of different products.  A standard pano head simular to the nodal ninja and they have a super robo automated panoramic head.  I have not used it my self,  but my good friend Eric Hanson over at xRez has been using their system for years.  I might have to swing by his shop and bring some beers to get hands on review for ya guys.
  • Ipix Products for consumer and DSLR cameras
    • Ipix has been around since 1989 and was one of the first companies to start doing 360 QTVR type stuff.  They carry Peace rivers' 3Sixty pano head but also offer lens and pano head for more consumer type cameras (Nikon P6000, P5000).
  • Panosarus
    • a budget pano head.
  • Manfrotto Pano head
    • One of the only "Big" camera accessory manufactures to get into the panohead business.  It is a solid head and does the job, but I cannot recommend it because of the complexety of its setup.  A previous company had one of these and basically it's great once it's setup and configured.. but I hope you have a good memory and some time if it needs to be assembled.
Lets not forget about tripods.  They are very important piece of the puzzle.  You don't need a crazy carbon fiber rig but if you got the cash spend some money on with with a self leveling ball head incorporated into the tripod like many of the Gitzos.

And lastly don't for get a good carrying cases and travel protection.  I love camera bags, but I have a lot of them.   But the one I use most is my Kata Rucksack.  I can jam my Camera, 8mm, 24-105mm, 16-35mm, my speedlight, battery charger, cleaning supplies, many cords and cables and I don't feel like I'm a hunch back with a big sign saying "MUG ME" i have lots of camera gear.

That's if for now... Next time we tackle the setup!  We'll configure out panohead, learn how to find the nodal point of any lens, and setup our camera.

Tuesday, September 22, 2009

HDR Aquisition - Introduction

Last week I went to a VES event on HDR usage in visual effects. After talking with a friend I realized that I have not written much of anything on HDR acquisition.

Most VFX Supervisors and artists now about HDRs. But they might not know how to capture and compile one. Lucky for us the tools have gotten much better in both areas!

Getting a good set of usable HDRs takes a bit of practice, familiarity with some basic photography rules, the right gear, and good communication with the First A.D. on set. Typically in pre-pro they're like yeah just let me know and we'll get you in there. But the reality is the second the "VFX Guy" drops his tripod on set to start taking HDRs the First A.D. is already yelling to "CLEAR SET!".

That's when practice and having the right tools on set pays off. And taking a fast and usable HDR data set will make your life a lot easier when you get back to the office.

I'm going to assume that we all know what HDRs are and how we use them in post production. But if you need a bit of a primer check out these links.
To make this a bit more digestible I'm going to break the whole thing down into separate entries.
  1. Gear - what kind of gear do you need to take HDRs.
  2. Setup - how to setup and and be "Johnny on the spot" on Set.
  3. HDR image capture - the process of actually taking the pictures.
  4. Stitching the HDRs together.
  5. Processing the HDRs and getting them into your software of choice.
The process is generally the same but there are many variations largely depending on what equipment you have. I'm going to break down my process using my gear but the general theory applies across many different gear sets.

Feel free to hit me up with any questions along the way and I'll do my best to answer them!