Please help with 105 mm Macro!

[Cacia]

Thank you, thank you, this is helping. So, when I see the fish portraits that have the black background, they are shot with a very high shutter speed?

 

[Warren_L]

Thank you, thank you, this is helping. So, when I see the fish portraits that have the black background, they are shot with a very high shutter speed?

Remember that the background is typically a function of ambient light (unless the background is really close to the subject, then artificial lighting may have an effect). The two things that will affect your ambient light is your shutter speed and aperature. Slowing of the shutter speed and/or opening up the lens will result in a lighter background. So darker backgrounds may possibly be because of a high shutter speed but also possibly smaller aperature.

 

[Cacia]

Warren, I was trying last night to take a macro shot with a light subject and a dark background. I could not do it, but I think it was because there was very low ambient light. Can you or somebody give me an exercise of...say shooting an object and getting a black background, in daylight? take a shell on the counter for example, should I be able to shoot that in normal daylight and get the aperature small enough to achieve that effect? How about some baseline settings......

stupid question, but it causes me confusion. Since the value I see on my camera for Shutterspeed is a value like "120" and since that really means 1/120, then as the denomonator goes up, my shutter speed is faster? For some reason that is a bit of a mind bender at depth. Hopefully it gets intuitive eventually. I am trying to practice topside. Dennis and I both laugh that we examined our settings (the on button) for the first time, at depth, with new cameras. He is actually very good which is irritating.

Also, if I go to someone's gallery and view an image, can I usually see their settings?

 

[Diver Dennis]

I just tried what you were decribing Catherine and I found that, without flash in manual, I was using 1/30 @ 3.5. Take a look at the photos in my gallery and you can see the settings I used for all my shots. All my U/W shots were with flash.

 

[Cacia]

Ohhh...how sweet. Sharing, are we?
I will try those settings. Dennis, do you have any trouble changing f-stop and shutter speeds at depth in that Ike housing? Mine might need adjusting or maybe I need to screw the camera down tighter. Sometimes it is a smooth as silk, other times the internal buttons are not getting enough traction.

well my thinking must be messed up because 1/30 is very slow, no? i thought the fraction was the percentage of a second, where the light has the opportunity to "do its thing". Am I confused? Like Alcina says the SS number goes up, the water gets darker. And 3.5 is a big aperature. I am going to try it RIGHT NOW.

You must be surrounded by a lot of Canadian white snow. That is definetly not working at this latitude.

 

[Diver Dennis]

I like sharing Catherine. For my housing at least, changing shutter speed and aperature is very easy in the housing and I am always experimenting. Make sure the adjustment knobs and buttons don't have greasy finger prints on them and yes, make sure it is screwed down tight.
1/30 is quite slow but I use it U/W all the time with my 10-22mm WA. The situation you were describing needs a lot of light to get into the camera, hence the alomost wide open f-stop and slow shutter speed. It's different when you use a flash.
Hope that helps. See, I want both of us to get better...

 

[Warren_L]

Warren, I was trying last night to take a macro shot with a light subject and a dark background. I could not do it, but I think it was because there was very low ambient light. Can you or somebody give me an exercise of...say shooting an object and getting a black background, in daylight? take a shell on the counter for example, should I be able to shoot that in normal daylight and get the aperature small enough to achieve that effect? How about some baseline settings......

It may not be possible to do so without artificial light, as changing your shutter speed and aperature when using natural lighting will affect all the available light - which means the subject in the foreground and the background will both be affected - brighter or darker, as you change your settings. To get one to stay the same and one to darken without individual foreground and background lighting may not be possible when just using ambient light.

When you are using artificial light like a strobe or a flash, the shutter speed may not affect the lighting of your subject (as the pulse of the strobe is going to be far faster than your shutter speed), but adjusting the aperature will (assuming you are not operating in TTL mode so that your strobe or flash output remains constant). In this scenario, the artificial lighting will have less effect on the background (assuming the background is significantly more distant than the subject). As a result, the lighting of the background would be due mostly to ambient light, which will be affected by shutter and aperature.

Here are a series of shots I took of an object (my cell phone, which just happened to by sitting on the counter at the time). These shots were taken in manual mode using artificial lighting (flash) to illuminate the subject, with some ambient light in the background.

The first series keeps a constant shutter speed of 1/50th sec, ISO 400, and adjusting the aperature from f/3.3, f/5.6, f/11.0, f/22.0.

The second series keeps a constant aperature of f/3.3, ISO 400, and adjusting the shutter speed from 1/50th, 1/125th, 1/250th, 1/500th.

As you can see, the subject in both series remains fairly consistent in lighting while the background adjusts. Also notice the change in the depth of field with the first series as the aperature changes.

 

[Diver Dennis]

Nice demonstration Warren. Thanks. I should point out the settings I was giving were for ISO 100, which is what I use U/W. Since I've only been shooting U/W for a month, I'm still in the many shots practice mode...

 

[Cacia]

Please tell me at f22 the DOF is better. (first series)

also, 1/500th is the fastest SP , correct? The faster SP= less light, darker background "ambient light", or as Alcina described "richer, darker blue water color"

If I have this wrong, ya'll are going to write me off. Whew, time to take a break and change my avatar or something...

I vote we take Warren as our personal advisor to Bali, Dennis.

 

[justleesa]

yeah, the smaller the fraction, the smaller your opening....1/4 of a pie and 1/8 pie, pieces are getting smaller

All depends on the picture they upload. If the details are included they will appear in the gallery.