Canon XT-AEB-P or AV? Help me here!

[Sepiana]

Hi everyone,

This weekend, I was practicing AEB shooting with the following settings in the Canon XT:

P (Program AE)
Continuous shooting
AEB = -2, 0, +2
RAW and/or JPEG

I have a Photomatix demo. In the tutorial they talk about shooting in the AP (A setting) mode, which I understood to be the AV (Aperture-Priority AE) mode in the Canon.

Now, here are my questions:

1. Which of the two is preferable?
2. Does it make a difference?

To be honest, I got a bit scared of using the AV mode -- it seemed too manual to me. You all have to remember that up to now, I had only used Full Auto. Just shooting in the P mode is a giant leap for me.

Thanks in advance!

[Chuck S.]

Sepiana, my two cents:

Shooting in Av (aperture priority) when using AEB (automatic exposure bracketing) will ensure that the depth of field (the front-to-back focus) is the same for all three images that you shoot. Av mode keeps the aperture at the setting you've chosen and adjusts the shutter speed to give you the meter's recommended exposure.

When using Av mode, especially with AEB, you do need to be concerned that the resulting shutter speeds aren't too slow if you're trying to do the photos hand-held. It would be good to do the whole operation using a tripod instead - and if using a tripod, turn off the IS (image stabilization) for your lens. So much to remember!

Av and Tv settings, like Auto and P, are automatic, i.e., the camera is determining the shutter speed or aperture to match the camera meter's desired exposure. However, they're not quite as automatic as Auto or P, either of which will adjust both aperture and shutter speed to hit the exposure value. But for AEB, you really only want the shutter speed to change between shots - so Av gives you that, while none of the other modes will necessarily do that.

Probably confused you more....but bottom line: the recommendation you read is a good one!

[Sepiana]

Hi Chuck,

Thanks a lot! That was fast! No, you didn't confuse me. However, I was hoping the answer would be to stick with the P mode (looking for the easy way out). But, I will follow your advice. Tomorrow, if the sun cooperates, I'll give the AV mode a try. To get the courage, I'll have some of that cognac Kev mentioned once. No, wait, not a good idea -- I'll have it afterwards to reward myself.

EDIT: Wish me good luck and keep your fingers crossed (and maybe your toes too?); I can use all the help I can get.

[Inspeqtor]

Originally Posted by Chuck S.

Sepiana, my two cents:

Shooting in Av (aperture priority) when using AEB (automatic exposure bracketing) will ensure that the depth of field (the front-to-back focus) is the same for all three images that you shoot. Av mode keeps the aperture at the setting you've chosen and adjusts the shutter speed to give you the meter's recommended exposure.

When using Av mode, especially with AEB, you do need to be concerned that the resulting shutter speeds aren't too slow if you're trying to do the photos hand-held. It would be good to do the whole operation using a tripod instead - and if using a tripod, turn off the IS (image stabilization) for your lens. So much to remember!

Av and Tv settings, like Auto and P, are automatic, i.e., the camera is determining the shutter speed or aperture to match the camera meter's desired exposure. However, they're not quite as automatic as Auto or P, either of which will adjust both aperture and shutter speed to hit the exposure value. But for AEB, you really only want the shutter speed to change between shots - so Av gives you that, while none of the other modes will necessarily do that.

Probably confused you more....but bottom line: the recommendation you read is a good one!

Sepiana,

As usual, Chuck is right on with his recommendations. I would just add to this the reason for turning off IS (Stabilizer) is because when the camera is hand-held there is a motor in the lens trying to keep the image still (not moving around). When the camera is on a tripod, the IS still tries to work, thus confusing the camera, into which it may bring some blurr into the photo. (Am I right with this Chuck?)

Also you need to remember to turn the IS back on when you take the camera off of the tripod!
I tend to forget from time to time

[Sepiana]

Hi Charles,

Thanks a lot! Prompt response! I'm free from the obligation though -- the Canon XT lacks IS. However, your advice is of utmost relevance to me; I'm getting closer and closer to get my XSi -- my DH hates Christmas shopping; therefore, I suggested he upgraded our camera and considered it his Christmas gift to me.

[Inspeqtor]

Originally Posted by Sepiana

Hi Charles,

Thanks a lot! Prompt response! I'm free from the obligation though -- the Canon XT lacks IS. However, your advice is of utmost relevance to me; I'm getting closer and closer to get my XSi -- my DH hates Christmas shopping; therefore, I suggested he upgraded our camera and considered it his Christmas gift to me.

Sepiana,

That is really good news! I do hope DH follows thru with your suggestion!

Merry Christmas early!!!!!!!!!

[BruceM]

Originally Posted by Sepiana

Hi Charles,

Thanks a lot! Prompt response! I'm free from the obligation though -- the Canon XT lacks IS. However, your advice is of utmost relevance to me; I'm getting closer and closer to get my XSi -- my DH hates Christmas shopping; therefore, I suggested he upgraded our camera and considered it his Christmas gift to me.

Sepiana - a quick point for you. With canon, IS is in the lens, not the camera. You might want to check your lens to be sure.

Also, no need to get the cognac out yet, the beauty of a digital camera, imho, is that you can take as many pics as you want and make as many mistakes as you need to in order to figure out how to do something. The cognac is for after you learn, the congratulatory "pat on the back" if you will.

Enjoy, and keep shooting.

Also, if you wouldn't mind, can you give any comments on your experience with Photomatix? I'm considering giving it a try myself as I'm interested in trying my hand at HDR.

Thanks.

[Chuck S.]

Bruce is right - Canon DSLR's don't have built-in image stabilization in the camera body; it's in the lens, if it's one with the IS designation. Thanks for clarifying that, Bruce! I've been using a point-and-shoot with built-in IS so much lately that I forgot that point...

[Sepiana]

Originally Posted by BruceM

. . .Also, if you wouldn't mind, can you give any comments on your experience with Photomatix? I'm considering giving it a try myself as I'm interested in trying my hand at HDR.

Thanks.

Bruce, thanks a lot for your advice.

No, I don't mind at all commenting on my Photomatix experience. However, be warned -- I'm the least qualified person to do that, as my experience consisted of a few hours, with the demo version. There are several forum members who are experts at HDR/Photomatix, and you'd be better off with their input, advice, and recommendations. But here it goes.

First, I didn't like the results. But, as I tried the different modes, I began getting better and better results. My best results came out when I, first, converted the RAW images in ACR, and, then, in Photomatix, used Exposure Blending. Also I need to point out, I didn't experiment with changing the settings sliders. All I wanted it was to go through the program to get the feel for it.

I intend to try Photomatix again. This time I'll shoot the images in AV, as recommended by Chuck. I'm waiting for a sunny and still day (wind and HDR don't seem to agree). I hope that I'll have some decent images in the near future to post in the Before and After forum, so I can get some advice. (I didn't save my images from my 1st experience -- I want to have a fresh start, now that I have more information.)

In summary, I'm pursuing my relationship with Photomatix and I'm considering purchasing the full version in the near future -- hey, I'm not a kid anymore (those days are long gone), but I still love playing around with toys.

I'd like to suggest the following:

1. Search the forum using "HDR" and "Photomatix" as your search terms -- you'll find a treasure of information from the experts.

2. Check these links:
http://www.hdrsoft.com/resources/tut_win/index.html
http://www.hdrsoft.com/support/faq_photomatix.html
http://www.photoanswers.co.uk/Advice...s/HDR-imaging/

[lruther1]

Photomatix is a great program. The attached hdr was put together with it; and has 6 different exposures that were blended. I usually shoot in full manual but Aperture priority would work as well. A tripod is a must as the images need to match exactly. I also shoot in raw so I can do the sharpening before exporting as tiffs and putting together in photomatix.