a few beginner questions

[mpderksen]

1. I have a Canon Rebel XSi. White balance options are fairly limited. Should I stick something white in the tank and use the Custom WB option?

2. No Macro lens (yet). Options are the stock 18-55mm, or an EF 50mm 1:1.8 fixed that I use for portraits. Which should I start working with until I can get a true Marco?

3. LEDs, with a standard blue channel and a white (with a few green, red and UV). Just use the Apex to kick both to 100%, then set the WB and go from there? I'm trying to avoid blue cast, but do like the fluorescence I get with the blues....

4. I'm clear on AV-priority mode, and DOF does depend on the subject, but what about exposure compensation?



I do shoot in RAW, and have Lightroom and PS for processing. Kill the flow, remote trigger, tripod, clean the glass. I'm good there.



Here is a really basic attempt of my torch coral from July of last year.

 

[Reef Bass]

1. If you're shooting in RAW and using Lightroom, there is no need to worry about in camera white balancing or custom white balances (which are applied in camera). Just adjust the color temperature slider during post.

2. Whichever floats your boat.

3. My lights are MH, so can't help you there.

4. DOF depends on the size of the aperture of your lens, not the subject. More or less of the subject will be in focus depending on the depth of field. A smaller lens hole (aperture), higher F number, will yield greater DOF. A larger aperture, smaller F number, will yield less DOF.

Exposure compensation boosts or diminishes exposure slightly at a given aperture / iso / shutterspeed combo. Personally I try to set exposure without it, but again, whatever floats your boat.

 

[mpderksen]

a few beginner questions

Just a starting point would be great for settings. I struggle to get really sharp focus (see image above). My gear isn't high end, but certainly decent.
What ISO should I set? Without a macro, I will likely have a fairly large aperture, so I won't need really long exposures. Really just want to shoot a few, show them here and then learn what I could have done better.
(Yes, I'm working on the coralline on the back a section at a time.....)

 

[mpderksen]

Any further input?

 

[Dkuhlmann]

I've found the following on Ebay and picked them all up and now playing with them for Macro shots. These work very well and you can use the lenses that you have currently for Macro shots.

As far as the white balance I can't really help you even though I have the same camera I'm still learning.

If you search around you can find all of these in one kit. There are many options.

http://www.ebay.com/itm/162026024002?_trksid=p2060353.m2749.l2649&ssPageName=STRK:MEBIDX:IT

http://www.ebay.com/itm/331093305823?_trksid=p2060353.m2749.l2649&ssPageName=STRK:MEBIDX:IT

http://www.ebay.com/itm/390968571503?_trksid=p2060353.m2749.l2649&ssPageName=STRK:MEBIDX:IT

 

[IPT]

I use exposure compensation a lot. Really depends on your subject and field of view. The camera knows to exposure for one thing, neutral grey (a 50% gray tone). On average a lot of scenes average out that way so it works. Try and shoot bright snow though, and the camera will make it grey. You'll then use exposure compensation to "overexpose" (as far as the camera is concerned at least) to keep the snow white.

All depends on the scene and what you're going for. For example in the picture I zoomed in tot he brigtest areas of the snowy mtn and set exp comp to +1 or more). Then I zoomed back and never looked at what the meter said again. I just checked the histogram (or looked for "blinkies") to make sure i didn't blow out the hot spots.



When i shoot the Aurora I often use exp compensation to -1 or -2. The scene is usually dark so 50% grey as the camera would strive for would over expose. Shooting RAW is always a good idea and does allow for some latitude. I usually bracket anyway just to make sure. On this Eagle I probably under exposed via exp comp and then just checked to make sure I didn't blowout the head feather detail. You cna get into manually merging (HDR if you will) to deal with super high contrast.



If you look at the rock in the left of your photo, it's blown out (no details). I find the top of the anemone a little "hot" too. Using two exposures, or just adjusting the same RAW image two ways) you could save the detail in that rock (and if you wanted to take it farther boost contrast overall).

Lots to learn, lots of decisions to make .