Eliminating Camera Movement Between Exposures

[anonymous]

How does one get multiple exposures to be perfectly aligned for HDR?

I purchased a solid Manfrotto tripod and still often get a slight movement in between exposures, especially when I have to change aperture/shutter settings in between shots. Just the slightest movement eliminates any sharpness. Ugh! How does one do it?

I'm shooting with a Canon Rebel (soon to be 450D). E.g., with a 70-200 2.8L IS lens, my existing tripods are not steady enough to try multiple exposure techniques.

[McQ]

Try using the Canon TC-80N3 timer remote control to pre-program a sequence of exposures. Avoid changing aperture (as this also influences DoF) and only vary the shutter speed when trying to capture a greater dynamic range. Other than that, make sure you have the tripod on a firm surface and that the pan/tilt or ballhead is VERY firmly locked in place.

On your 70-200 mm lens, make sure that you have it mounted on the tripod using the mounting collar; this places less torque on the pan/tilt head and lessens the impact of any vibrations.

Also, use mirror lock-up if available. This causes the camera's SLR mirror to flip up prior to the start of your exposure. You can then begin the exposure once you are sure that any vibrations have dissipated that were caused by the mirror flipping up.

For really long exposures, mirror lockup is negligible since mirror slap vibrations (if any) account for only a fraction of the exposure time. The danger zone is generally anywhere from 1/8sec to 0.5 seconds exposure time.

Finally, longer lenses are more susceptible to vibrations (and any vibrations last longer before dissipating), so this is also something to be aware of.

Hope some of this helps.

[_GUI_]

You can use camera bracketing so you even don't need a sophisticated remote control. I built mine myself and cost was less than 10 EUR.

In the 450D you will be lucky to enjoy up to -3,0,+3 bracketing (former cameras only have -2,0,+2) so if you set your camera in M mode and make -3 be a shot with its histogram to the right but always preserving the highlights, the +3 shot will actually be 6 f-stops higher and that will give you an astonishing DR expansion.

A 40D user in other forum reported he uses LiveView + Mirror lockup working together. In this situation the mirror seems to remain constantly locked up so it will not shock the camera in any way during the exposures. Vibrations are then reduced to a minimum (just the unavoidable shutter and wind) so alignment will be simply impossible to improve unless you change to a better tripod.

[DanielJ]

Remote capture is yet another route when convenience is not a deciding factor. DSLR Remote Pro for Canon cameras is quite a handy tool with a trial version available. The range of remote operations vary by camera, with some now even focusable by mouse wheel (450D among them : ). I use a 10' USB cable. Firewire is also an option. Cable length will become an issue, but I can't say at what point personally.
I would also recommend turning off autofocus on the lens barrel to rule that change out as well.

[realvision]

I only registered to post this Tip :-)

If you are using a lens with Image Stabilization built in, AND you have the camera on a tripod.
Make sure you have the IS turned off. The way IS on lenses work is that it is always looking for some sort of shake/vibration to compensate for, and if it does'nt find any it baffles it and can introduce artificial correction where not needed!

Secondly select AEB on the camera and use the timer function to take the shots. that should sort you out!

Cheers!


** woops! didnt read that last line by Daniel above . Thats a good tip too!

[realvision]

Ok I think this warrant a longer post...

Here's what I'd do - I have a canon 400 D

1) Set the camera on the Tripod

2) Switch off the IS on the lens barrel if you have a lens with IS

3) Set the camera to Av mode - It is important to use Av mode versus Tv mode

4) Frame your shot

5) from Menu 2 go to AEB and bracket it for +/-2

6) Set the camera to Timer mode

7) Take your shot

The Camera will fire 3 shots automatically -

There No more shake


Optional - Lock the mirror and do manual focus if you wish


Regards!

[hobbes]

Nikon D50

1) Tripod.
2) Aperture priority mode.
3) Bracketing option on -2,0,+2.
4) Infrared Remote. $15

I never touch the camera. Now if only I could figure out some way to do this for more stops.

[_GUI_]

Originally Posted by hobbes

Now if only I could figure out some way to do this for more stops.

If used in a clever way, the -2,0,2 bracketing can give you a better DR expansion. What I do is adjust aperture/shutter so that the least exposed RAW in the set, i.e. the initially called -2, is as exposed as possible, i.e. exposed to the right, just before starting to blow the highlights. That will give you the maximum achievable DR expansion with 3 shots bracketed -2,0,+2, you will expand your camera's DR by 4 f-stops. You can read about this here: http://www.guillermoluijk.com/articl...e/index_en.htm. I blend the 3 files produces with: http://www.guillermoluijk.com/tutori...oise/index.htm

Let's say your D50 manages to capture noise-free 7 or 8 f-stops, you will go to 11 or 12 f-stops now.

BR

[rc53]

Whether IS needs to be turned off depends on the lens; some recent Canon lenses, for example, recognise that the camera is on a tripod so that IS doesn't have to be turned off, though it is probably a good idea to do it anyway.

Manual everything: focus, exposure - change only the speed - and white balance.

Same workflow as for panos - apart from changing the exposure, which must be constant.

Bertie