Bought a book, learned a few things

[OpticalPrime]

Well I wanted to say thanks to the people to recommended "Understanding Exposure". I bought it Saturday and about half way through it already. I have learned a great deal. Before this weekend I would say 99% of every picture I have ever taken was with "AUTO" mode. I didnt really understand the ISO, Aperture, Shutterspeed very well. (still not 100%), but I have alot better idea now. If you dont mind, I have a few questions Id like to get straight.

Currently I have a fixed lens digital camera (Canon S2 to be exact).

1. ISO - So unless its really dark, I typically always want a low ISO like 50 on my camera? Takes longer to write to disc, but less grainy pictures... am I correct here?

2. Aperture - This is one I think is the most difficult to crasp. From what I understand the Fstops in my fixed lens is totally different than of an SLR. My range is 2.7 - 8. 2.7 is "wide open" and is used mainly for depth of field. So when taking a picture of something near (like a flower) and want the background blurry. Set to 2.7 and focus on the flower... F8 is when I want the entire picture in focus.... But my F8 is really like an SLRs F32?? From what I understand thats the main advantage to Fixed Lens.... So does that mean my 2.7 really isnt a 2.7?? So Im going to have a harder time making those blurry background pictures?

3. Shutterspeed - I think I understand this one. Fast shutter speed of like 1/1000 when taking a picture of something moving, slow shutter speed of like 1 sec if taking of a waterfall, etc...


I know all of this is going to take alot of practice for me to master. I feel like a 16 year old kid in drivers ed who took the writen, but not the driving test.. lol

Wife and I went down to her home town this weekend to see her grandfather who has cancer and on way I took a few pictures in MANUAL mode. I actually set the ISO, Aperture, Shutter speed all myself. I never even knew what that -2/3 or +/-0 thing meant... kinda cool. But these pictures are actually properly exposed pictures I took... Probably not the best pictures, but cool to me cuz they werent done in AUTO

I think Im gonna get down this technical stuff, I think my biggest problem right now is I dont know WHAT to take a picture of, or what ANGLE, etc... After reading a little on the book of HOW to take pictures, I got excited and went out and didnt even know what to shoot... lol

[TxManx]

Originally Posted by 00bolt

1. ISO - So unless its really dark, I typically always want a low ISO like 50 on my camera? Takes longer to write to disc, but less grainy pictures... am I correct here?

You'll want to use an ISO appropriate to the lighting conditions...50 for bright and sunny, 100-400 for cloudy/shadows, etc...and higher ISOs in darker conditions.

Originally Posted by 00bolt

2. Aperture - This is one I think is the most difficult to crasp. From what I understand the Fstops in my fixed lens is totally different than of an SLR. My range is 2.7 - 8. 2.7 is "wide open" and is used mainly for depth of field. So when taking a picture of something near (like a flower) and want the background blurry. Set to 2.7 and focus on the flower... F8 is when I want the entire picture in focus.... But my F8 is really like an SLRs F32?? From what I understand thats the main advantage to Fixed Lens.... So does that mean my 2.7 really isnt a 2.7?? So Im going to have a harder time making those blurry background pictures?

The aperture size on your camera is in direct correlation to your sensor size...that is where most confusion starts.

Your Canon S2IS has a 6mm-72mm lense which equates to a 36mm-432mm on a full fram 35mm camera. When it says F2.7-3.5, it means those are valid aperture sizes for that sensor size.

At your wide angle setting, your lense is 2.7 - fast but with more DOF than a telephoto would provide. At the longest zoon setting, your lense is 3.5 - not too slow, but with a fraction of DOF due to telephoto.

As your last picture shows, if you zoom in on an object, it compresses the elements in the picture, and provides the 'blurry background' you're looking for...

On SLR type cameras, the option is available to use a larger aperture (like 2.8, 1.8, etc) but with a wider angle lense, so that the background blur is possible without having to use zoom...

Originally Posted by 00bolt

3. Shutterspeed - I think I understand this one. Fast shutter speed of like 1/1000 when taking a picture of something moving, slow shutter speed of like 1 sec if taking of a waterfall, etc...

This one you have nailed down....just remember that anything below 1/30 will likely be blurry from the camera moving/hand shaking/etc - unless you use a tripod.

This is where adjusting your ISO comes into play....if you're at ISO 50, and it requires an shutterspeed of 1 second to expose properly, you can bump your ISO up to 100, to reduce shutterspeed to 1/2 second, or bump ISO up to 400 to reduce shutterspeed to 1/8 second.

If your camera goes up to ISO 800, then you're at 1/15...etc, etc, etc.

(apologies if my math isn't 100% accurate...but I believe those increases in ISO sensitive correlate to those shutterspeeds)

Don't worry about what you're taking a picture of - as long as it's something you want to take a picture of. I know people who will play with their camera and a pencil for a few hours just to see the different DOF they can get with a new lense.

::SHRUG:: have fun, play, learn...

[OpticalPrime]

Well I was thinking that once I get my basics down and if I continue to really enjoy this to splurge and buy an XTi Canon. So other than being able to buy additional lenses (zoom, macro, etc) what would be my biggest advantages? (obviously 10mp is bigger). I think being able to do those "blurry backgrounds" is a big bonus. Its hard to get that effect with my current camera.

[OpticalPrime]

One more quick question if you dont mind. I have this Cardinal that I see in my backyard about once a week (and I dont really keep an eye out for him that often) so I assume he prolly there alot. So if I wanted to take a picture of him in the birdbath or in the tree and I wanted him CLEAR and the background BLURRY, how would I do that?

I would "think" that I would set to F2.7 and adjust the shutterspeed according to what camera says -2/3 , etc to the correct exposure. With ISO as low as light allows.

But playing with camera right now, Im not getting a blurry background. Seems like the only way I get that blurry background is if im in MACRO mode and shooting something close up. No way the cardinal is gonna let me get 6 inches from him, lol

[TxManx]

Originally Posted by 00bolt

Well I was thinking that once I get my basics down and if I continue to really enjoy this to splurge and buy an XTi Canon. So other than being able to buy additional lenses (zoom, macro, etc) what would be my biggest advantages? (obviously 10mp is bigger). I think being able to do those "blurry backgrounds" is a big bonus. Its hard to get that effect with my current camera.

Biggest reasons I can think of for moving to an XTi Canon (or any dSLR) are:

1) camera response - I've yet to find a P&S (point and shoot) that turns on as quickly, focuses as quickly, etc - as a dSLR.

2) RAW - Yeah, I prefer to shoot RAW.

3) camera lense options (although - lenses can be a huge PITA, and you will be hard pressed to find a single lense that gives you the dynamic range that your S2 has (36-432mm is an awesome focal range!)

4) making custom changes to your settings - you can switch modes, ISO, shutter speeds, etc. extremely quickly with most dSLRs...

Ken

[TxManx]

Originally Posted by 00bolt

One more quick question if you dont mind. I have this Cardinal that I see in my backyard about once a week (and I dont really keep an eye out for him that often) so I assume he prolly there alot. So if I wanted to take a picture of him in the birdbath or in the tree and I wanted him CLEAR and the background BLURRY, how would I do that?

I would "think" that I would set to F2.7 and adjust the shutterspeed according to what camera says -2/3 , etc to the correct exposure. With ISO as low as light allows.

But playing with camera right now, Im not getting a blurry background. Seems like the only way I get that blurry background is if im in MACRO mode and shooting something close up. No way the cardinal is gonna let me get 6 inches from him, lol

Well - with your particular camera, I'd stay 10-15 feet away, use shutter speed of at least 1/500 and zoom in to him.

The zoom will isolate him from the background and the shutter speed should stop him in motion (even fully zoomed in - which increases the effects of camera shake).

As for why you're not getting blurred backgrounds...try this as a test:

Go outside, set your shutter speed to 1/500, and use your zoom to isolate something - a flower, or a bird, or a person, etc...but make sure there's 10-15' of space between it and it's background.

I think you'll get the blur you're looking for...

Ken

[OpticalPrime]

I guess my backgrounds just werent far enough away from the subjects. It sorta worked this time, just not blurry as I would want. For instance, if a bird is in a tree, the other branches, leaves, etc arent 10+ feet away, so they dont get blurred... but if I zoom on say the birdbath, my fence is a grey blur because its far enough away...

one thing I dont understand though, I set the aperture to 2.7, but when I zoom it changes on its own to 3.5, why doesnt it stay at 2.7

[OpticalPrime]

for example, look at these pics. Are these green "blurs" 15 feet away from the birds? Like the Cardinal picture he took, that green blur is probably just the grass 3-4 feet behind the bird on the ground, yet it is very blurred...

http://www.texasphotoforum.com/forum...ad.php?t=49899

[Big Dog]

Originally Posted by 00bolt

one thing I dont understand though, I set the aperture to 2.7, but when I zoom it changes on its own to 3.5, why doesnt it stay at 2.7

Aperture numbers are ratios. It is the ratio of the diameter of the opening of the iris "aperture" to the focal lencth of the lens. For instance: a 50mm lens, with a diameter of the aperture of 12.5mm, is f/4. Half that (6 1/4mm) is f/8.

So, as you zoom out, the focal length increases, but the opening stays the same, so the ratio changes. There are some zoom lenses that maintain a constant "F-stop" setting as they zoom, but both the focal length and the diameter of the iris are changing to stay in the same proportion.

To answer one of your earlier questions, does the 8 on your P&S = 32 on an SLR? No. It just means the SLR lens is capable of "stopping down" to a smaller aperture. The f-stop setting controls the amount of light making the exposure, as does the shutter speed. So, f/8 is f/8 for any lens. Different lenses have different aperture ranges, just as different cameras have different shutter speed ranges.

This will all be on the test.

[TxManx]

Thanks David! :)

I know just enough about this stuff to answer some questions, but the technical details are still a bit vague!

Ken

[TxManx]

Originally Posted by 00bolt

for example, look at these pics. Are these green "blurs" 15 feet away from the birds? Like the Cardinal picture he took, that green blur is probably just the grass 3-4 feet behind the bird on the ground, yet it is very blurred...

I was using the 15' for your example...

Given your camera's specifications, and the lense information the photographer provided (when I followed your link), you should theoretically be able to take pictures of birds like that with your camera...the background might not be as evenly blurred, but your focal reach is about the same, and his maximum aperture on his lense is 5.6, vs. the 3.5 on your camera...

Ken

[OpticalPrime]

well playing around with my camera here at work... lol I think mine must be limited or something. The only way I can really get that blur effect is when Im about 5-10 feet away from the object, and the background is like 20 feet away from it. Otherwise, the background keeps showing up. Maybe that is because of my fixed lens has the large depth of field?? But the only way I can get it to work is when I have an object here in the store, and put it in front of the window and the trees outside become a blur... but if I aim at the trees or cars or whatever, nothing behind them blur...

[TxManx]

Are you setting your aperture yourself, or ? What does the EXIF info show?

[OpticalPrime]

ya im putting it on manual and setting to 2.7, when I zoom in it changes obviously, but what do you mean by EXIF? if you mean the -2/3 thing then yes that shows up and I adjust the SS accordingly

[TxManx]

Your camera embeds information into the images it takes... that information is called EXIF information.

Using most decent picture viewers (I personally use freeware called Irfanview) - you can view the information about your images such as the camera model, the exposure information, if the flash was fired, the date, etc...

Ken