[Alvin]

Yep, a lens can be said to be "fast", but an aperture is a size-related thing and should be referred to as large or small to avoid confusion. Oh, and don't get confused by "small f-stop", which is a large aperture.

Oh, some people say "bigger" shutter speed, that makes no sense either.

Think first :-).

How about "Stop down a few stops?" I can't make heads or tails of that sentence. Does it mean use a smaller aperture or a bigger one?

[ccallana]

What I used to do (and still do now) is shoot a few shots in P (Program) mode. I do this when I'm in doubt about the lighting situation.

After taking the shots, I quickly review the exif data in playback mode pressing INFO a couple times. I can see a histogram there, and the Av and Tv values.

I use this to play in M (Manual), Av, or Tv Modes. This is how I'm learning about the effects of changing settings on my cam. I shoot a lot of misses this way, but I'm developing a feel of what not to do and what I can get away with.

Hope this helps.

I did this a ton today - took my son for an "adventure" walking on the old railroad tracks with my DL and F50/1.7. I was taking shots down the tracks curving off into nowhere - in P mode I kept getting blown out sky in the shots - so I took the numbers that P gave, switched to M and started playing from there. I found in those conditions, I had to go to -2EV to really make it look right (at least to my eyes) and have some detail in the sky and trees.

Then I kept forgetting I had the camera in M mode and then kept getting way underexposed pics in other situations... blah!

[ccallana]

How about "Stop down a few stops?" I can't make heads or tails of that sentence. Does it mean use a smaller aperture or a bigger one?

My understanding is Stop down means a smaller aperture (larger number) - so if you are at f/2.8 and Stop down a few stops, you'd end up at f/5.6 or f/8

[SpecialK]

How about "Stop down a few stops?" I can't make heads or tails of that sentence. Does it mean use a smaller aperture or a bigger one?

That is a smaller aperture (larger f-number). You are going "down" in size.

[Alvin]

I did this a ton today - took my son for an "adventure" walking on the old railroad tracks with my DL and F50/1.7. I was taking shots down the tracks curving off into nowhere - in P mode I kept getting blown out sky in the shots - so I took the numbers that P gave, switched to M and started playing from there. I found in those conditions, I had to go to -2EV to really make it look right (at least to my eyes) and have some detail in the sky and trees.

Then I kept forgetting I had the camera in M mode and then kept getting way underexposed pics in other situations... blah!

It takes some time to get used to reviewing the pictures immediately after shooting and remembering to turn the dial back to P mode when the light changes, even very slightly. When I was using a DSLR for my first real shoot I used a Fuji S3 Pro - I couldn't believe how many mistakes I had made because of the changing lighting conditions (indoor, outdoor, don't forget the flash, WB).

ccallana and SpecialK - Thanks for clarifying the stop down a few stops.

[THarp]

What it really comes down to (per the original authors inital post) is your person preference on what you want for Depth Of Field (DOF). Original poster asked when to use f4.5, or f8.0 ect.

It all depends on what you want for DOF. For instance at f1.7 pretty much your focus point is in focus and everything starts to blur from there (in front of and behind that point). Usually portraits you use f1.7 or "that end" not to confuse it, so that you blur the background. If more than 1 person you want to stay midway like 4.5 or better because you want both people in focus.

If you are shooting landscapes you would probably want f11, 16 ect.
I seen a couple people say that most lenses are at there sharpest at f8.

"Fast Lenses" is a reference to lenses that have very wide aperture like 1.4, 1.7, etc. They are called "fast" because they allow you to achieve a higher/faster shutterspeed due to letting in more light. Which means you can handhold a shot that with a "slower" lens (one that starts at f3.5) you would have to use flash or a tripod.

Here is a pretty good link worth reading.
theWonderOfLight Dot Com

Tracy

[buckethead]

Lots of good information in this post.

Lot of things make much more sense now. Trail and error is going to be my best friend as I learn through this.

[Serpiente]

hello people!

First of all.. I am new here.. hello!

Last friday I gave myself a K10D as a present! I thought I deserved it

I made some great pictures.. some good close-ups and portrets of the dog..


But there is one thing I still cant (I am very green to digital reflex cams).
I want to make pictures of moving objects. For example a running dog, flying bird, driving car.
In the P mode it did well, but I wasnt sattisfied.. I want the background more blurry.

When I use the Tv mode I can change the shutterspeed, but I cant get it faster than 0,3".. I know it can be faster.. How do I change it?
I read somewhere that 1-60 (0,02") or 1/250 are perfect for moving objects..


greetings!

[Lowell Goudge]

Some people refer to fast lenses as lenses with a huge aperture. I get caught using the term too. Lenses can't control shutter speed.

the reason lenses with large apatures are called "fast" is because when all else is equal, i.e. available light, and film speed, these lenses allow faster shutter speeds due to their larger apature.

remember the light hitting your sensor is a function of apature and shutter speed.

A note here for the OP. WHile there have been some books mentioned, I would not worry too much about the title. Any book on general photography will do. they will all explain the remainder of the terms that people have thrown out here.

I once recommended to a new forum member (and new DSLR Owner) to go out and get a book - any book, then read it, take some photos, and re-read the book after looking at his photos. It is a learning process, just for the technical part. The artistic part is even more difficult

[Serpiente]

I already found the solution.. there are numbers with and without the ". I got it