Fed up - aperture bollocks

[UKBob]

I feel I really dont know much about controling my camera And the fact that I still cant seem to get any decent results when away from my tripod and light tent is really pissing me off now, as my results are consistently inconsistent

Two things:

1) The ****ing exposure I shoot apperture priority, and usually check the shutter speed to ensure its not too slow. I do this because my shots are nearly all blurry, and far from sharp.

Check out the two photos below (unedited, just resized)


I had to shoot at f2.8 to get enough light to give me a 160th shutterspeed which was still to slow to get sharp image. Even so, these shots were taken 1 second appart. Why are they exposed so differently??? I took dozens and dozens and dozens of photos this weekend, and nearly all of them are either dark and underexposed, or blurry. Therefore ruined!




The F***ING SHUTTER SPEED camera shake problem is driving me NUTS!! I seem to need a shutter speed of at least 160-250 if shooting telephoto to get a shot which isnt blurry. I use the 24-70L lens. 70mm isnt that long! Yet camera shake is ruining nearly all the photos I take outdoors

Why are the beer photos above exposed so differently? What settings might I check. And why when using the same settings, do photos come out so differently?

Does anyone else struggle to find enough light to get the shots they want? Please tell me Im not alone with the camera shake - why is it so bad? Is it because my lens is physically quite a big and long one, even though Im only shooting at 70mm?

Edited by UKBob on Wednesday 12th July 13:02

[UKBob]

By the way... the first darker photo of the tree stump was shot at 1/640th. I dont know why the camera made the decision to take one shot of the stump at that speed, and the next one at 160th. The shutterspeed is obviously accountable for the exposure, but why are results so random and inconsistant.

SLR's are hard work. Dont mind a bit of work, but Im going nuts not finding out where Im going wrong each time, I feeling Im not learning anything. And feel powerless to control subjects.

[dcw@pr]

sure you haven't got bracketing turned on

fwiw, that first beer one doesn't look like motion blur to me, its just that the focus is at the back of the glass rather than the front. And that is also why your exposure is different - in the 1st shot you have focussed and metered at the back, so the exposure will be read from the light foam and the dark table, whereas in the 2nd shot you have focussed at the front, and hence the exposure will be almost entirely from the foam.

wrt to movement blur, i have two points. Firstly, don't forget about your crop factor when you are thinking about the magical inverse focal length law. Secondly, the magical inverse focal length law is not quite rubbish, but is definately very flexible. Take more time and concentrate on being steady and you will get better results. And if your name is Ken Rockwell then you can get sharp results from a 1200mm lens at half a second

[J111]

UKBob said:

1) The ****ing exposure I shoot apperture priority, and usually check the shutter speed to ensure its not too slow. I do this because my shots are nearly all blurry, and far from sharp.

I fear that most of your photographs are out of focus, rather than shaky. Your method ensures that you have almost no depth of field so, if your camera captures focus at the wrong point, the whole image may appear blurred.

UKBob said:

I had to shoot at f2.8 to get enough light to give me a 160th shutterspeed which was still to slow to get sharp image. Even so, these shots were taken 1 second appart. Why are they exposed so differently???

I suspect that you have the camera set to spot metering. The two shots show reasonable exposure in the centre of the frame. In the first that is the cut face, in the second the shadowed area of the trunk:

UKBob said:

I took dozens and dozens and dozens of photos this weekend, and nearly all of them are either dark and underexposed, or blurry. Therefore ruined!

The F***ING SHUTTER SPEED camera shake problem is driving me NUTS!! I seem to need a shutter speed of at least 160-250 if shooting telephoto to get a shot which isnt blurry. I use the 24-70L lens. 70mm isnt that long! Yet camera shake is ruining nearly all the photos I take outdoors

Again, I seriously doubt that the issue is camera shake.

UKBob said:

Why are the beer photos above exposed so differently? What settings might I check. And why when using the same settings, do photos come out so differently?

You've experienced exactly the same problem as in the tree photos. In the first photograph the point of focus and exposure is the rear of the glass, where the glass has a dark grey background (the table.) This point is well exposed but the white surface of the beer is burnt out. In the second the point of focus and exposure is at the front of the glass, where the glass has a white background. This is slightly underexposed, but this is to be expected since the camera 'assumes' that the point it is exposing from is 18% grey.



These show the sharp point in both images, with an 18% grey bar for exposure comparison.

UKBob said:

Does anyone else struggle to find enough light to get the shots they want?

Not in normal lighting conditions.

UKBob said:

Please tell me Im not alone with the camera shake - why is it so bad? Is it because my lens is physically quite a big and long one, even though Im only shooting at 70mm?

See above

[graham@reading]

There's no shame in using Program mode

To be frank, I use that 75% of the time, excluding airshows (shutter priority) and specific wildlife tasks (aperture priority usually).

[dieselnut]

I've just bought a Canon 350D, playing around this lunchtime outside, I aimed to go through most of the settings to see what they do... I've never owned up until now, anything more exciting than a "reasonable" point and shoot, so all these options are alien to me.

Anyway, getting to the point, I tried Shutter and Aperture priority, neither gave me really good shots, program mode... spot on, and I was shooting with a 70-210 lens on at full stretch. (Basically because my subject matter scared the bejeezus out of me, and I didn't want to get any closer, especially as he/she had little-un's in the lake next to me)



You can see quite exagerated there what's been said anout depth of field, the bridge of the beak is perfectly in focus, but the "chin" is blurred, that's got to only be about 3-4 inches (he was a biiiig bird) so with your pint shot, 4 inches means the focal point of the glass is all in, the rest isn't.

Just my thoughts

Matthew

Edited to add: full res shot at www.eeek.org.uk/~matthew/gallery/album03/IMG_0398?full=1

Edited by dieselnut on Wednesday 12th July 13:59

[J111]

dieselnut said:

You can see quite exagerated there what's been said anout depth of field, the bridge of the beak is perfectly in focus, but the "chin" is blurred, that's got to only be about 3-4 inches (he was a biiiig bird) so with your pint shot, 4 inches means the focal point of the glass is all in, the rest isn't.

The same exposure issue has also reared its head there, taking the meter reading from the beak has left the plummage blown out.

I feel a rant about learning your craft on manual film cameras coming on

[graham@reading]

J111 said:

I feel a rant about learning your craft on manual film cameras coming on

I did ok thanks to the benefits of RAW and EXIF. Not to mention LCD reviewing of course. Figured everything out through reading up, experimenting and correlating the results with the settings.

Much the same as people who learnt with manual cameras, just I didn't have to write down the settings, develop the picture, THEN compare.

[dieselnut]

Unfortunatly the 350D doesn't do spot metering, so if you wanted to sort the exposure out, you'd have to do it by hand, unless I'm missing something major.

Most of the shots today weren't aiming for a perfect picture, more a "see what happens when I..."

[J111]

dieselnut said:

Unfortunatly the 350D doesn't do spot metering, so if you wanted to sort the exposure out, you'd have to do it by hand, unless I'm missing something major.

What you could do is to take a meter reading of the plummage, using partial metering, then use that reading to take the pic as a whole. Easier said than done with a moving (and potentially pissed off) target !

Another alternative is to use auto-bracketing.

[mechsympathy]

J111 said:

I feel a rant about learning your craft on manual film cameras coming on

OTOH there's a marked improvement in the quality of my pics over the course of my 7 month trip recently. I would have learnt next to nothing if I'd had a film camera.

But yes, you're probably right.

[dcw@pr]

graham@reading said:

excluding airshows (shutter priority)

[dieselnut]

J111 said:

dieselnut said:

Unfortunatly the 350D doesn't do spot metering, so if you wanted to sort the exposure out, you'd have to do it by hand, unless I'm missing something major.

What you could do is to take a meter reading of the plummage, using partial metering, then use that reading to take the pic as a whole. Easier said than done with a moving (and potentially pissed off) target !

Another alternative is to use auto-bracketing.

I did think about autobracketing as an option, would RAW mode and post processing help ?

What I did realise though, a 210mm lens means you still have to be <6 foot from the subject to take a photo that size.. time to get a bigger lens

[UKBob]

dcw@pr said:

that first beer one doesn't look like motion blur to me

Correct. There NO motion blur in ANY of the pics I posted. My fault for not typing out my frustrations more clearly.

But I do have a camera shake problem. This is the same problem I was whining about the week I got my new lens, which Ive learnt, can be pinsharp when used properly, and all too often its blurry when shutter speeds are not whacked right up. I didnt mean to confuse the issues, and am quite sure that my other pics are suffering from camera shake.

dcw@pr said:

your exposure is different because in the 1st shot you have focussed and metered at the back, so the exposure will be read from the light foam and the dark table, whereas in the 2nd shot you have focussed at the front, and hence the exposure will be almost entirely from the foam.

J111 said:

stuff

J111 said:

taking the meter reading from the beak has left the plummage blown out.

So, by changing to metering the full frame and not just a spot, im not going to have dark murky backgrounds I assume... Thanks for the edit/repost of the pics, and the explanation. Much appreciated!

I know Ive asked before, but one more time... lets assume I have shaky hands what shutter speed would an "average camera holder" need to use, on a physically BIG 70mm lens, with the 1.6 crop factor?

Edited by UKBob on Wednesday 12th July 15:23

[GetCarter]

I have had this problem before and it was beacuse I had forgot I was bracketing. (Which I do most of the time).

May well be a 'check the fuel tank first' moment. Haven't read whole thread so sorry if this is covered.

[dcw@pr]

UKBob said:

But I do have a camera shake problem. This is the same problem I was whining about the week I got my new lens, which Ive learnt, can be pinsharp when used properly, and all too often its blurry when shutter speeds are not whacked right up. I didnt mean to confuse the issues, and am quite sure that my other pics are suffering from camera shake.

I see. Not trying to be harsh, but in that case, it MUST be user error. Without question it is true that some people have steadier hands than others, and I think that the large majority of photographers do not try to get close to what they are capable of. As I said in the first post, really try to concentrate on taking your time over a photo. By this I do not mean standing there for a minute and composing it perfectly. I mean that once you have done that bit, take the extra second to make sure you actually are holding the camera steady when you relese the shutter. It is very easy to rush the split second when the magic happens, and try to get on with the next photo ASAP. Slow down!

[imperialism2024]

Now, I do use spot metering, but to deal with the situations you displayed, the first thing I'll do is lay with exposure compensation. In the tree stump situation, I'd probably use -1 to -1.33 stops exposure compensation. Also, you're always better off underexposing shots if you shoot in RAW since you can brighten them in post-processing, but you can't recover blown highlights from overexposed shots.

Also, I just checked the EXIF data, and spot metering is on in the 30D. Which seems to explain everything, then. It's not entirely a bad thing, as long as you're careful with how you use it.

Once you get a decent enough grasp on how your lens(es) perform, you could also just go to full manual mode. I like to use that in difficult lighting situations where I run the risk of excessively under- or over-exposing shots. With f/2.8, you should be able to use 1/500 sec or faster in broad daylight without an issue. I know I was seeing well exposed shots this past weekend on my D70 with f/3.5 and 1/3200 sec in broad daylight.

[dcw@pr]

UKBob said:

[quote=dcw@pr]I know Ive asked before, but one more time... lets assume I have shaky hands what shutter speed would an "average camera holder" need to use, on a physically BIG 70mm lens, with the 1.6 crop factor?

techincally it's 1/70 divided by 1.6, therefore 1/112. If I were you, on an average day outside, set your camera at f/5.6 (otherwise DOf and lens quality will dictate you will not get the sharpest pics), unless you need a smaller/bigger apperture for DOF effects. Then adjust your ISO to somewhere where your shutter speed will not drop below 1/125, to be on the safe side. Combine this with my post a minute ago and you should be fine.

btw, the "set your ISO" trick only works if you are using a canon, or are in bright sunshine

[graham@reading]

dcw@pr said:

graham@reading said:

excluding airshows (shutter priority)

What?

DoF isn't much of an issue due to the distance, they're usually reasonably good days, weatherwise, obviously outdoors so natural light etc...there's really no need to do much on the aperture front at all. So I'll meter on some nearby grass (pretty damn close to 18% grey), stick with 1/1000 or 1/800 depending on the weather for the jets, 1/250 for the props and 1/60 for the choppers. Works for me.

Edited by graham@reading on Wednesday 12th July 15:34

[Podie]

Bob, what camera are you using..?