The Canon EOS and Photography Forums

Hi,

I can't figure out how to get more then a 3 shot burst in Auto Exposure Bracketing. I use a lot of HDR and need more then 3.


This is what is confusing. Under "setting exposure compensation" : You can set the exposure compensation up to +- 5 stops. If you want to set the Exp. Comp beyond  +-2 stops you should follow the instructions for "Auto exposure bracketing" which read this feature takes Exp. Comp. to a step further by varying the exposure automatically with the three shots +-2 stops increments.

Very confusing unless I see the actual steps. What I keep getting is a 3 shot burst, one under, one over, and one on (EV). I've been trying to find a copy of the manual so I CAN PASTE IT IN THE FORUM MESSAGE.

I don't belive you can take more than 3 shots when autobracketing. If you want more than 3 shots you will have to do it manually.

A 3-shot burst +/- 2 stops from the starting point is the AEB limit of the T2i. That three shot burst can be combined with the T2i's 5 stop exposure compensation thus you do not have to start the burst at standard exposure. It works the same way on my 7d except it allows +/- 3 stops rather than 2. The AEB setting method combined with the graphic scales make AEB with or without ex.comp an easy way to use and understand the feature.

Canon Manuals in PDF form can be found here:
http://www.usa.canon.com/consumer/controller;topic=609.msg7236?act=SupportIndexAct

Go through the drop down menus to find your product and select  the "downloads" tab when you get there.

I got the PDF  of the manual, but it's locked and you can't copy anything. I don't have a capture progrm. But what I do seem to understand it this.

1. Exposure Compensation Settings will have to be changed more the once to get more then a 3 EV set
2. You will then have to set the Auto Exposure Bracketing spread to, lets say, one under, one over.
3. After the first 3 shot burst, you would have to chance the Exposure Compensation up or down and then take another burst.
4. This would result in six shots at totaling a 6 EV set.

I hope I'm explaining  this right. Lots of extra sets and the possibility  of camera movement during resets....not good

Ref  pages 87 and 89

You are explaining it correctly and as you said you would have to shoot two sequences to get more than three different exposures.  With HDR  becoming more popular it would seem  Canon should extend AEB to 5 exposures but nothing up through the 5DMk2 allows that. 

Thanks for the confirmation and support

Here's the deal

Your eye sees 11 f stops (EV's)

Film sees 8 - 10 (depending on the film)

Digital sees 4 - 6

so HDR is trying to compensate for making the wrong choice of media by adding a couple f-stops by combining the highs from one and the lows from another with the middles from a third exposure

the camera only does 3 copies of an image as a "set" - but it can electronically adjust them instead of doing it manually

HDR is kind of a "gimmick" - it's not actually a true image (more for "special effects") and what you have on your monitor is NOT what you get in print out (nor is it what others see because people have their monitors set differently) - yes people are doing it and think it's new, spiffy; but it's kind of a fad because you are dealing with a fact of physics - digital just can not see as many f-stops, EV's as other media; it's in the nature of the beast

Eriq
Your understanding of data pertaining to dynamic range is different then mine. Though I'm skipping a lot of fill about the topic it breaks down differently from what I've read.

The human eye -- 24 stop range.
Film and digital vary depending on film and sensor including A/D conversion. Numbers I've seen put film at about 5-6 stops for positive and 7-8 for negative film.  Monitors about 8.5 stops. Most  P&S cameras were in the range of positive-negative film but DSLRs are now in the 11-12 stop range (raw) and one pro Nikon over 13 stops. DR is one test that DxO puts a sensor throught when comparing raw output of a model's sensor.
I suspect this is a topic that has numbers all over the map as over the years I've seen different. I've come to respect  DxO and ClarK Vision as two of the better internet sources.