canon eos 30d technical questions

yooperdooper

nothing happens when i press the depth of field preview button.maybe i am overlooking something........i set the aeb and whte auto braketing simulteneously and only got three shots i should have got nine.can anyone explain this?thank you.john

Tee Why

Stop down on the aperture before you press the preview button. To test it out set the aperture to f22 and try it. You should see the viewfinder get really dark and if you have enough light the depth of focus should increase as well.

If you press it with the aperture wide open, nothing will happen.

As for the bracketing question, I'll leave it to others more familiar with the feature.

Richard

yooperdooper wrote:

nothing happens when i press the depth of field preview button.maybe i am overlooking something........i set the aeb and whte auto braketing simulteneously and only got three shots i should have got nine.can anyone explain this?thank you.john

Are you shooting RAW, by chance? On a 20D, white balance bracketing does not apply when shooting RAW or RAW + Jpg. Don't know about the 30D though.

yooperdooper

thank you richard and twhy for the responses.i was not shooting in raw.and i don't think raw plus jpeg.

yooperdooper

on another subject:i experimented with my new eos 30d and took 444 experimental shots trying different settings.it seems to me that in general the photos are blurry.can anyone explain this?

Richard

yooperdooper wrote:

on another subject:i experimented with my new eos 30d and took 444 experimental shots trying different settings.it seems to me that in general the photos are blurry.can anyone explain this?

Hard to say without seeing some examples. Post a few with EXIF data and maybe we can sort it out.

cmason

yooperdooper wrote:

nothing happens when i press the depth of field preview button.maybe i am overlooking something........

Your aperture must be small for the preview button to work. In other words, you need the aperture to be set at a high number, like F22 or higher. If your aperture is f4 or so, you will not see any difference. This is because the lens stays wide open so you can see thru it. The camera sets the aperture just before the shutter fires, so the preview shows what it looks like with the aperture closed.

yooperdooper wrote:

i set the aeb and whte auto braketing simulteneously and only got three shots i should have got nine.can anyone explain this?thank you.john

Check again. I tried this myself...the shutter fires 3 times, but you get 9 images. Tricky...it does some of this in camera.

Cuong

yooperdooper wrote:

on another subject:i experimented with my new eos 30d and took 444 experimental shots trying different settings.it seems to me that in general the photos are blurry.can anyone explain this?

What auto focus mode is set on the camera (Single Shot, AI Focus, AI Servo)? Which focus points are selected (all 9 or just 1)? Is the lens set to AF (auto focus) or MF (manual focus)?

When you say blurry, is that caused by camera movement (low light, slow shutter speed) or the subject's out of focus caused by one or multiple settings mentioned in the questions above?

Cuong

yooperdooper

yooperdooper's blurry pictures
when i took the pictures the camera was on a tripod.therefore camera shake probably did not happen.i was playing around to learn the camera with a multitude of shutter ,aperature and exposure settings and other settings.i used single shot exclusively.very few were manual focus.most were single pt af.i am not real sure how to use the single pt af .i may not have focused on the subject with the single af pt.most of the settings were way off because i was experimenting.i will post several pictures.

yooperdooper

a-dep mode
on my canon eos 30d i attempted to use the a-dep mode. the manual says to move the af point over the subject.....acording to the "selecting the af point" section the a-dep mode is selected automaticly .how can i get around this?

gryphonslair99

cmason wrote:

Your aperture must be small for the preview button to work. In other words, you need the aperture to be set at a high number, like F22 or higher. If your aperture is f4 or so, you will not see any difference. This is because the lens stays wide open so you can see thru it. The camera sets the aperture just before the shutter fires, so the preview shows what it looks like with the aperture closed.



Check again. I tried this myself...the shutter fires 3 times, but you get 9 images. Tricky...it does some of this in camera.

I'm sorry buy I think that you are a bit confused on the use of the DOF preview button.

Using the DOF preview button takes some getting used to. At f22 your DOF is huge. Not much to see in the way of DOF most of the time. At a wide aperture such as f1.4 you will be able to see your DOF range adn see what is in focus and what is outside that DOF or out of focus. The whole purpose of the DOF preview button is to be able to check the DOF prior to the shot and make sure you have the DOF you want. That way you can stop down if you need more DOF or open the lens wider if you want less DOF.

cmason

yooperdooper wrote:

on my canon eos 30d i attempted to use the a-dep mode. the manual says to move the af point over the subject.....acording to the "selecting the af point" section the a-dep mode is selected automaticly .how can i get around this?

Dont use A-DEP. Use Tv, Av or M. Adjust your aperture as wide open as possible (lower number) to get blurry background that A-DEP promises to make automatic.

Richard

cmason wrote:

Dont use A-DEP. Use Tv, Av or M. Adjust your aperture as wide open as possible (lower number) to get blurry background that A-DEP promises to make automatic.

Hmm...either I'm confused or you are. What you have said is true but I think that A-Dep tries to guarantee that everything covered by all the AF points will be in focus. I have only tried it a few times on a 20D, but what it seems to do is pick a very narrow (higher number) aperture. Since this doesn't tell me anything that I didn't know in the first place, I stopped using it.

ivar

Richard wrote:

Hmm...either I'm confused or you are. What you have said is true but I think that A-Dep tries to guarantee that everything covered by all the AF points will be in focus.

I have tried it once or twice, just to try it, but I never really used it. I don't understand the usefulness of this mode, tbh

Scott_Quier

DOF Preview Button - all the above seems to be dancing around what this button does and how it is used, so I'll throw my $.02 into the discussion:

The DOF preview button is just that. You set your aperture and press the button and you get a preview - i.e., before the image is made. The purpose is to help you determine if your DOF is what you want in the final photo.

How does it work. Well, you set the aperture to something between wide open and fully stopped down. The setting really doesn't matter. The DOF button, when pressed, will close the aperture to that setting. You will be able to see the result through the view finder.

Bear in mind that your view will become increasingly darker as you stop down the lens more and more. So, this can make it difficult to actually see the DOF differences as the aperture gets smaller and smaller.

I know this works in manual mode and in Av mode. Don't know if it works in any other mode. Does it make sense for it to work in Tv? Not to my mind but my mind is not the mind of Canon

The bottom line is that the button works no matter what aperture you set. If you set to wide open and press the button, well the aperture will be wide open - you won't see a change. D'oh.

Hope that helps clear the air some....

ivar wrote:

I have tried it once or twice, just to try it, but I never really used it. I don't understand the usefulness of this mode, tbh

Would seem to me that this is one way to get the requisite DOF while, at the same time, maximizing the aperture - thus the shutter speed - at a given ISO.