Shutter speed

[mercurial]

Ok, so hopefully I'll have the 450D very, very soon (just sorting out a few things). If you are shooting in Manual mode, you get to choose all your settings right? You have more control over the shots you are about to take, as opposed to the aperture priority or shutter priority, in which you select your value and the camera automatically adjusts every other setting for you. I wanted to know that if you're shooting in Manual mode, how do you know which value to assign to your shutter speed?

 

[BigAl-sa]

Ok, so hopefully I'll have the 450D very, very soon (just sorting out a few things). If you are shooting in Manual mode, you get to choose all your settings right? You have more control over the shots you are about to take, as opposed to the aperture priority or shutter priority, in which you select your value and the camera automatically adjusts every other setting for you. I wanted to know that if you're shooting in Manual mode, how do you know which value to assign to your shutter speed?

You have an exposure meter in the viewfinder. You up/down the speed until you have the "needle" where you want it

 

[bwana]

Unless you have plenty of ambient light it usually depends on what you're shooing. If having a greater depth of field is important you're going to want a smaller aperture when means a slower shutter speed to let in the necessary light. If you're photographing a moving object then you're going to sacrifice DOF by opening up the aperture to give you enough light for that faster shutter speed.

Adjusting the ISO helps maintain a useful balance but that comes at a cost - noise.

A rule of thumb is that you ideally want a shutter speed equal to (or greater than) the focal length of the lens. 50mm = 1/50th, 200mm = 1/200th etc.

(EDIT - this all made sense in my head as I was thinking about it )

 

[mercurial]

Thanks guys

 

[bwana]

Purely for practical reasons unless I know I need to do something out of the ordinary I keep mine on AV.

 

[BigAl-sa]

A rule of thumb is that you ideally want a shutter speed equal to (or greater than) the focal length of the lens. 50mm = 1/50th, 200mm = 1/200th etc.

I've always been a bit wary of this. When I was learning about photography, this applied to telephoto lenses only (f>100mm). Now folks seem to apply it to everything and you see them talking about 1/10s for a 10mm lens - you will get camera shake at 1/10s. My thought on the matter for handholding lenses is try and keep the shutter speed above 1/72s for lenses below 100mm and then use the 1/f rule on focal lengths above that.

Am I making any sense?

 

[BigAl-sa]

Purely for practical reasons unless I know I need to do something out of the ordinary I keep mine on AV.

Ditto. I use M when I use the flash though - I hate the way Canon handles the flash in Av.

 

[mercurial]

Purely for practical reasons unless I know I need to do something out of the ordinary I keep mine on AV.

I was planning on doing the same...

 

[bwana]

I've always been a bit wary of this. When I was learning about photography, this applied to telephoto lenses only (f>100mm). Now folks seem to apply it to everything and you see them talking about 1/10s for a 10mm lens - you will get camera shake at 1/10s. My thought on the matter for handholding lenses is try and keep the shutter speed above 1/72s for lenses below 100mm and then use the 1/f rule on focal lengths above that.

Am I making any sense?

What you say works for me. I can hand hold my 50mm at speeds lower than 1/50th but I wouldnt expect to do the same with my 16mm

I've got my own approach to slow shutter speeds. If I'm at all concerned it might be too slow I just blast away until the buffer is full. One is always usable.

Ditto. I use M when I use the flash though - I hate the way Canon handles the flash in Av.

I'm still not experienced/confident enough with the flash yet so often just go full P.

My problem with full time manual is that being left eyed I cant adjust the aperture without pulling the camera away from my eye.

 

[mercurial]

Another question, though off-topic - I'm not sure if the 450D supports downscaling to 10MP(I know you can downscale to lower MP), but if it does, if I shoot in 10MP, will my images contain less noise?

 

[BigAl-sa]

My problem with full time manual is that being left eyed I cant adjust the aperture without pulling the camera away from my eye.

I also use my left eye, but with my 350d, I can get to the aperture button with my thumb then roll the wheel with my index finger. Sounds tricky, but once you've done it once, you get the hang of it quite quickly (if you want, I'll ask my missus to take a pic of me doing it).

Of course, with the 40d it's a bit easier with the second wheel (even though that's directly under my nose ).

 

[BigAl-sa]

Another question, though off-topic - I'm not sure if the 450D supports downscaling to 10MP(I know you can downscale to lower MP), but if it does, if I shoot in 10MP, will my images contain less noise?

Interesting question! I think it depends how the camera does the size reduction - by using less pixels in the sensor (should be less noise), or decreasing the pixels by software once the pic has been taken (should be same noise).

 

[mercurial]

Interesting question! I think it depends how the camera does the size reduction - by using less pixels in the sensor (should be less noise), or decreasing the pixels by software once the pic has been taken (should be same noise).

I see. Cos those 2 extra MP does not really matter to me. I'd happily shoot at 10MP if I will get less noise.

 

[ldmelsa]

I see. Cos those 2 extra MP does not really matter to me. I'd happily shoot at 10MP if I will get less noise.

dude

the 450d has awesome lowlight
what are you worried about?

 

[bwana]

I also use my left eye, but with my 350d, I can get to the aperture button with my thumb then roll the wheel with my index finger. Sounds tricky, but once you've done it once, you get the hang of it quite quickly (if you want, I'll ask my missus to take a pic of me doing it).

Of course, with the 40d it's a bit easier with the second wheel (even though that's directly under my nose ).

I can do it in a pinch but its way too uncomfortable and at the end of the day why bother? For normal shooting I prefer controlling my DOF. If I could make it so that the dial defaulted to the aperture and only I needed to depress the the AV button to adjust shutter speed then it might be a different story.

Everything is fine when I use the grip and shoot portrait

 

[mercurial]

dude

the 450d has awesome lowlight
what are you worried about?

Lol. I'm being petty again

 

[koffiejunkie]

Ditto. I use M when I use the flash though - I hate the way Canon handles the flash in Av.

I actually like the way flash works in AV - normal AV with fill. My only problem is by the time I actually get desperate enough to stick on the flash, it's *so* dark that the shutter times end up being 1/2 or lower and I get this nasty ghosting because subjects won't stand still. I hate flash.

I also use my left eye, but with my 350d, I can get to the aperture button with my thumb then roll the wheel with my index finger. Sounds tricky, but once you've done it once, you get the hang of it quite quickly (if you want, I'll ask my missus to take a pic of me doing it).

What button do you have to press? On my film rebel it's the * (I think, or the one next to it). Uncomfortable for my hands, but not that bad. I wouldn't shoot like that all the time though.

Interesting question! I think it depends how the camera does the size reduction - by using less pixels in the sensor (should be less noise), or decreasing the pixels by software once the pic has been taken (should be same noise).

I may be wrong, but I think the 40D (and mostly likely the 400D too, since it has the same sensor) just combines more sensor elements per pixel to get the lower resolution. I have tested this to some extent - took a situation where I know noise is going to get me, and shot the same thing on tripod both at 10MP and at the smaller version 7MP and 5MP, IIRC). It definitely gave a cleaner image.

 

[koffiejunkie]

I've always been a bit wary of this. When I was learning about photography, this applied to telephoto lenses only (f>100mm). Now folks seem to apply it to everything and you see them talking about 1/10s for a 10mm lens - you will get camera shake at 1/10s. My thought on the matter for handholding lenses is try and keep the shutter speed above 1/72s for lenses below 100mm and then use the 1/f rule on focal lengths above that.

Am I making any sense?

You are. I agree, it's not a all-round rule. There's no way I can get 1/10 sharp, not matter what lens I use. Yes, I've tried with my Sigma 10-20

One to remember, of course, is that crop DSLRs complicate this somewhat. 100mm on the Canon gets the same field of view as 160mm would on film, so you're better off getting your shutter speed up to at least 1/150.

 

[BigAl-sa]

What button do you have to press? On my film rebel it's the * (I think, or the one next to it). Uncomfortable for my hands, but not that bad. I wouldn't shoot like that all the time though.

Here's a pic of the back of the 400d (Bwana)
http://www.dpreview.com/reviews/canoneos400d/page4.asp

and here the back of the 350d (me)
http://www.dpreview.com/reviews/canoneos350d/page4.asp

The top button in the row of buttons on the right of the screen is the exposure adjust button in A, T and P modes. In M mode it becomes the aperture adjust button.

 

[mercurial]

I was wondering how the flash works with all of this?