Please help!

[jerryg]

Right now I would say, I'm pretty desperate for answers. The most confusing thing for me is how aperture, ISO, and the basic fundamentals of how exposure works, and how all these things work together to make great pictures. I have bought several books, but I'm still having a hard time putting it all together.

One of the problems I have understanding is what settings to use outdoors vs. indoors... are there some general guidelines?

I have considered going to school, but don't have a lot of spare time. Does anyone know where to find video or DVD tutorials to explain these fundamentals? I am more of a visual learner, so a CD or DVD would be a quicker way for me.

Here is an inventory of my equipment:

Camera - Cannon EOS 30D
Lens - Cannon EFS 18-55mm
Cannon EF 75-300mm f/4-5.6 iii
Sigma 105mm f2.8 DG Macro
Flash - Cannon 430EX

If someone could help me, I would really appreciate it.

Like I said... I have no idea what I'm doing.

Thanks,

- Jerry

 

[Stevedevil]

Hi Jerry

Im A newbe to this site, but I know enough to take some great photo's, we use ISO as a speed of film, which means the way light affects ona an exposure, with your camera being digital, this can be seen as an amount of light hitting your sensor in a time period, shutter speed, and FOCUS through the photo will be determined by F stop ( focal length ).

Lower f readings means the object you are shooting, against backgroubd focally, so low f stop ( f 2.8 ) will make ( as long as focus correct ) a great pic of something in close view with the background not in focus, this will depend on shutter speed too,

If your using digital, then spend some time writing settings of camera for certain shots, and adjust f stop and shutter speed on camera, and work on results

Cheers

Steve

 

[EOS_JD]

Steve
I kind of see what you are saying but there's a whole lot more to exposure than this.

Buy Bryan Peterson's book "Understanding Exposure" that will explain all.

It needs a whole book to explain it. Can't be done in a few lines really.

Regards
Jim

 

[jerryg]

Thanks guys... I really appreciate you helping me out.

Do you know of any video tutorials on the subject?

Thanks,

- Jerry

 

[EOS_JD]

Thanks guys... I really appreciate you helping me out.

Do you know of any video tutorials on the subject?

Thanks,

- Jerry

Not really although I'm sure there must be some.

Here's some good links that will help you on your way.

http://www.photonhead.com/beginners/
http://en.wikipedia.org/wiki/Aperture (look at the in Photography section.
http://www.photoxels.com/tutorial_iso.html


http://www.mir.com.my/rb/photography/fototech/apershutter/index.htm
http://www.mir.com.my/rb/photography/fototech/apershutter/exposure.htm
http://www.mir.com.my/rb/photography/fototech/apershutter/shutter.htm
http://www.mir.com.my/rb/photography/fototech/apershutter/aperture.htm

 

[Torus34]

Check

http://www.thephotoforum.com/node/36

 

[EOS_JD]

Going to add a bit to steves thread

shutter speed, and FOCUS through the photo will be determined by F stop ( focal length ).

Focus is nothing to do with the fstop.

here's an explanation of the fstop. - http://members.tripod.com/~Prophotoman/fstop.html

The aperture is the camera's opening. The wider the aperure opens the more light it lets in. Wide apertures are in the f1 - f2.8 range. The max aperture of most expensive zooms is f2.8. Consumer zooms are smaller like f4.5-5.6 and don't let in as much light so slower max shutter speeds!

Prime lenses (or fixed focal length lenses) are cheaper and faster. Look at the 50mm f1.8 it lets in more than twice the light of (1.333 stop faster) some zoom lenses costing over £1000 GBP. But the zooms are usually so much more useful.

The aperture does also control the depth of field - the amount of the image that is in acceptable sharpness. this can vary from a few mm to infinity and is dependant on the aperure used, the focal length of the lens used and the distance to your subject.

So as you can see this probably all sounds very complicated but can be pretty much mastered very quickly by reading the right resources (Understanding Exposure) and practicing lots!

ISO, shutter speed and aperture (fstop value) all work together to create a single exposure. Some shots you need a lot of depth of field (everything sharp) like a landscape so small apertures like f16-22. this will mean slow shutter speeds as you are cutting the amount of light reaching the sensor. Wide apertures like f1.4 are great when you need fast shutter speeds or a very small depth of field (just a few mm in focus) perhaps a portrait where all you want is a sharp eye and a blurred face......

Sometimes you want fast shutter speeds (shooting a footballer in action) other times you want slow shutter speeds (blurring a waterfall - or shooting a footballer and inducing some motion blur to create movement in the image.....)

the options are endless and you decide what you want and when you want it within the confines of your equipment.

Hope I've explained a little?!

regards
Jim

 

[jerryg]

Going to add a bit to steves thread



Focus is nothing to do with the fstop.

here's an explanation of the fstop. - http://members.tripod.com/~Prophotoman/fstop.html

The aperture is the camera's opening. The wider the aperure opens the more light it lets in. Wide apertures are in the f1 - f2.8 range. The max aperture of most expensive zooms is f2.8. Consumer zooms are smaller like f4.5-5.6 and don't let in as much light so slower max shutter speeds!

Prime lenses (or fixed focal length lenses) are cheaper and faster. Look at the 50mm f1.8 it lets in more than twice the light of (1.333 stop faster) some zoom lenses costing over £1000 GBP. But the zooms are usually so much more useful.

The aperture does also control the depth of field - the amount of the image that is in acceptable sharpness. this can vary from a few mm to infinity and is dependant on the aperure used, the focal length of the lens used and the distance to your subject.

So as you can see this probably all sounds very complicated but can be pretty much mastered very quickly by reading the right resources (Understanding Exposure) and practicing lots!

ISO, shutter speed and aperture (fstop value) all work together to create a single exposure. Some shots you need a lot of depth of field (everything sharp) like a landscape so small apertures like f16-22. this will mean slow shutter speeds as you are cutting the amount of light reaching the sensor. Wide apertures like f1.4 are great when you need fast shutter speeds or a very small depth of field (just a few mm in focus) perhaps a portrait where all you want is a sharp eye and a blurred face......

Sometimes you want fast shutter speeds (shooting a footballer in action) other times you want slow shutter speeds (blurring a waterfall - or shooting a footballer and inducing some motion blur to create movement in the image.....)

the options are endless and you decide what you want and when you want it within the confines of your equipment.

Hope I've explained a little?!

regards
Jim

WOW! Thank you so much. Actually thanks to all of you for answering my questions.

Yes, all this does sound a bit complicated, but after doing more research yesterday, I think some of it started to click (no pun intended).

I did go to Amazon and bought "Understanding Exposure". Also I did find some DVD''s on the basics, (Digital Photography Unleashed and Digital Sports Photography Made Simple) and picked them up for relatively cheap.
Both DVD's got really good reviews and according to all the people that bought them, they seemed to explain the basics very well. After I will get them I will let you all know if they were worth it.

I do have another question... what is a reason why someone would want a "fast" lens like you explained above? What would be the benefit, or any at all, of using one as opposed to using the same lens with a normal stop?

Thanks for your help,

- Jerry

 

[Torus34]

Fast lenses have larger diameters than slower ones. This means that when you open the diaphragm of a fast lens all the way, more light can flow through than when you open the diaphragm of a slow lens all the way.

If you stop down the diaphragm on a fast lens and on a slow lens [both of the same focal length] to the same f number, both will transmit exactly the same amount of light. The fast lens will have some f numbers at the low end of the scale that the slow lens will not have.

Next, since you can let more light in with a fast lens by opening the diaphragm further than on a slow lens, you can use a faster shutter speed without underexposing the shot. Or, if film, you can use a slower and less grainy film. [For digital rigs, you can use a lower ISO setting and get a less grainy image.] Another way of looking at this is that you can shoot in dimmer light with a fast lens than you can with a slow lens.

As you might suspect, there's a price to be paid. Fast lenses, for a number of reasons, cost more than slow lenses of the same image-making quality. And as you open the diaphragm to larger and larger openings [smaller f numbers], the depth of focus decreases [the range of distances in front of and behind the focus point which are in sharp focus becomes shallower.]

 

[EOS_JD]

Fast lenses have larger diameters than slower ones. This means that when you open the diaphragm of a fast lens all the way, more light can flow through than when you open the diaphragm of a slow lens all the way.

This really depends on the lens' focal length. Compare a 50mm f1.8 very fast diaphram (better called the aperture) with the 600mm f4L IS aperture and you'll see ewhat I mean

If you stop down the diaphragm on a fast lens and on a slow lens [both of the same focal length] to the same f number, both will transmit exactly the same amount of light. The fast lens will have some f numbers at the low end of the scale that the slow lens will not have.

But the faster lens will generally be much sharper as most lenses do better when stopped down a bit.

Next, since you can let more light in with a fast lens by opening the diaphragm further than on a slow lens, you can use a faster shutter speed without underexposing the shot. Or, if film, you can use a slower and less grainy film. [For digital rigs, you can use a lower ISO setting and get a less grainy image.] Another way of looking at this is that you can shoot in dimmer light with a fast lens than you can with a slow lens.

This is the main reason to buy fast lenses. You can shoot in much lower light than with a slow lens.

As you might suspect, there's a price to be paid. Fast lenses, for a number of reasons, cost more than slow lenses of the same image-making quality.

The price of the lenses generally links to both the focal length and aperture. Wide or long focal length lenses are generally more expensive than normal range lenses.

The 50 f1.4, 85f1.8, 100 f2, to name but a few are very nice fast prime lenses. Sigma make a nice 28-75mm f2.8 which is a great fast zoom almost comparable with the Canon 24-70f2.8L which is about 3x the price. You can find good lenses if you look. The 50mm f1.8 bucks the trend of fast lenses costing more. It's poor in build quality terms but is fast and sharp and costs very little (about $100 I believe - £70 in UK). But generally faster zooms in particular cost more especially at longer focal lengths. I have a 70-200 f2.8L IS which costs £1300 in the UK!! THe 600mm f4L IS is about £6k!!!

And as you open the diaphragm to larger and larger openings [smaller f numbers], the depth of focus decreases [the range of distances in front of and behind the focus point which are in sharp focus becomes shallower.]

Depth of field is not only down to the size of the aperture but also the distance to your subject, the focal length and the type of camera you use. 1.3x, 1.5x, 1.6x, 2x or Full frame cameras all have different field of view and different dof using the same lenses.

Say using a 1.6x camera like 350D/400D/20D30D for example

I shoot a subject 3m from me with a 300mm lens at f8 and the depth of field is 3cm!!

Using a 50mm f1.4 at 10m and the dof is 2.16m

So remember the focal length makes a difference and so does the distance to the subject. Macro lenses need to shoot sometimes at very small apertures like f32 to get everything sharp because they are very close to their subject. This means using a tripod generally because of the very slow shutter speeds.

As I said above there's a lot to learn.