Converting between Gain and f-Stops

So cameras work in Stops and composite packages use Gain. To convert between the two we need to do a bit of log maths. Heres how.

To convert from Stops (f) to Gain

Gain = 2f

To convert from Gain to stops (f)

f = logGain

This is equivalent to:

f = ( log10 Gain ) / ( log10 2 )

If you want to see why then we’ll need to look a little deeper at log maths
Continue reading

Camera Data

It’s worth checking out arenafilm who have a detailed database of filmbacks and lens combinations for various cameras.

Also dpreview have a review of sensor sizes for DSLRs.

I’ll try and keep a useful summary here.

Company Model Film Back aspect Pixels
Arri Alexa 26.136 x 14.702 mm / 1.0290 x 0.5788” (Monitoring/EVF) 16:9 3168 x 1782
Arri Alexa 23.760 x 13.365 mm / 0.9354 x 0.5262” (ProRes) 16:9 1920 x 1080
Arri Alexa 23.760 x 13.365 mm / 0.9354 x 0.5262” (RAW) 16:9 2880 x 1620
Red Epic 5120 x 2700

HDR Photography Equipment

I take a lot of HDR images for vfx work. I’m on a quest for the perfect setup that’s super fast to use on set. Here’s the HDR photography equipment and software I’m investigating. I’ll add more as I find it.

Everything HDR

Control your Canon EOS with your Android device The specs on this look amazing. Frankly I’m temped to replace my iPad with and Android tablet just to try this out.

Mod your canon dslr firmware using Magic Lantern firmware.

Includes HDR Bracketing for stills and hdr video (which is just nuts frankly)

magic Lantern view

CHDK is a great project for Canon’s Point-and-Shoot cameras. CHDK gets loaded into your camera’s memory upon bootup and is a temporary change to the firmware.

It runs simple Lua Scripts. You can write your own or download them from the community wiki.

Try HDR_Fast_Shooter

Some links for auto bracketing exposures. Using software or remote control

Control your camera using a scripting language HDRCapOSX

Expensive do everything dslr remote control promote

There’s also OnOne’s dSLR Remote for the iPhone … unfortunately you still need a laptop to connect to your camera and run the software. But it has some useful applications.

trigger Trap

Trigger Trap Produces a bunch of devices and an app for the iPhone that will trigger your DSLR in creative ways using various sensors and timers.