You said "...(I miss the exact moments I press the shutter)"... I may be misunderstanding your question, but that sounds like shutter lag, not a card write or buffer problem. I shot sports for over a decade, and when I switched to digital the shutter lag was a distinct and definite problem, but I do not ever remember a card write or buffer speed problem.

If I did misunderstand, my apologies.

1) You really will be hampered without a tripod! If at all possible put some kind of strap on the one you have any bring it.
2) I can't envision an on-camera flash providing the quality of light which will enhance photos in an ice cave. You need to light from the side for texture, or better yet back light the ice.
3) Go get a spare battery at your first opportunity!
4) Wide angle lens. It's relatively easy to get closer in a cave, but you're very limited as to how far you can back up. If you were to take a second lens, there might be an opportunity to use a macro lens (emphasis on might).
5) That said, ignore any of our advice that doesn't comfortably fit with your equipment or way of working. In the end, you need to get in there with what you are comfortable with and get some pictures! Enjoy, learn, be safe.

1. I've never heard the term "light size" before.
2. I'ts not the distance of the light source from the subject or the size of the source alone. It is a relatively broad light relatively close to the subject that provides the diffuse light that wraps around the subject.
3. A relatively small light source very close to the subject will provide a broad, diffuse light to wrap around the subject while a large or broad light at a comparatively long distance is a spectral light source providing a harsh light and sharp shadows. Use of a light box or umbrella to create a broad light source a few feet from the subject usually works, but the final result is dependent on the subject size, distance between light source and subject, and size of the light source.

At the same subject magnification in the final photograph, the bokeh is dependent upon the lens used, focal length (if a zoom), and the aperture. Sensor size is not a factor.

At the same subject magnification in the finished photograph, the bokeh is dependent upon the lens and aperture, but not the size of the sensor.

[quote=JasPetrie]

None-the-less, you are violating the creator of X-Plane's copyright! Not for profit, and no harm done, but violating just the same!

The moon is bathed in sunlight. It is a "Sunny 16" exposure. (Set aperture to f/16 and time to the reciprocal of the ISO/ASA rating, i.e., f/16 at 1/200 at ISO/ASA 200 .) Of course, that shows the moon as it actually appears, gray, and we perceive it as quite bright because we see it against a black background and so most prefer it opened up a stop. The f/6.7 at 1/800 and ISO/ASA of 200 noted above is a sunny 16 exposure using a higher shutter speed to stop its motion, and opened up 1/2 stop. The moon is very small in a big black sky so it is very hard to meter, but this formula always works in manual mode.

The answer is yes. Of course, in the Nikon line, full frame digiyal is a relatively recent offering (unless you count the Kodak/Nikons at the start of the digital era).

For 98% of our needs we will never see a difference between any of these top end lenses. That said, I will now expound the advantages of the Nikon. I bought one of the first Nikon 70-200 VR lenses when they first came out a dozen or so years ago. At the time I was shooting high school and college sports professionally in and around New Jersey. My equipment was getting a lot of use! Then I went digital and no longer had a film budget to worry about - my usage went up dramatically! I have gone through the shutter box on a D100 and a D70, I believe they are rated at 100,000 exposures, plus wore out a Nikon 35-105 and a Sigma lens of similar focal length.

Through all of this the Nikon 70-100 VR was my primary lens. Usually shot wide open to stop the action. Indoors and outdoors, football, soccer, field hockey, cross country, etc., etc., that lens has never let me down. I shot in good weather and bad (a soccer game in the remains of Hurricane Ivan - game got called at the half because of the weather, but I got the pictures). If you are contemplating that kind of heavy duty usage, then definitely go for the Nikon. "It takes a licking and keeps on ticking." If not, then you have a nice array to choose from. One thing, though, for those action sports, I would definitely insist on the f/2.8 rather than the f/4.0.

Yes, the "image plane" is curved, though not exactly a spherical segment with modern lenses using aspherical elements, et al. (And I misspoke when I wrote of the "circle of acceptable focus". Sorry, I shouldn't try to think that deep into the night.) There is loss of acuity, as well as light fall off, the further you get from the center of the image with all lenses. Even Blads. This however, is not the reason for the apparent distortion using wide angle lenses for portraiture. It is geometry, the nearer parts of the subject are proportionately much nearer than those further away, disproportionately enlarging those nearer elements. This is demonstrated by comparing two photos each with two people at differing distances from the camera shot at different focal lengths - photographing them close to the nearer one so that he appears fairly large with a wide angle lens will magnify the distance between them, and if you use a telephoto, moving so the nearer subject appears the same size as in the other photo, the apparent distance between them will be compressed.

But this begs the question whether using just the center portion of an FX lens in a DX camera, will give you a discernibly better image than using the same lens on an FX camera with the same pixel count (i.e, a D7100 vs a D600). I don't know. I'd love to explore that further, but I think it should be in a dedicated thread. I've enjoyed this exchange of thoughts, Doyle Thomas

Wow, how esoteric! And how unrelated to portrait photography. 1) I'm using Nikon lenses with great fat "sweet spots"; 2) I may need to defocus or use a diffusion filter to obtain the most attractive portrait of my subject (obscure the pores and blemishes). Your argument is strong, and persuasive, for document copy, and similar uses where exacting precision is important, but not for portraiture. My statement stands: "It ain't the format, it's the photographer!"

I have great respect for Hasselblad, their technology is second to none. I have sat through presentations by Hasselblad Reps and don't remember discussion of the circle of acceptable focus being a primary issue. They did emphasize their square format for viewing and for versatility, cropping easily to either horizontal or vertical.

I'd love to follow up on your argument, that the APS-c format provides some image quality advantage, but I don't believe this thread is the place. The question that started this was which format would give kwbybee the best portraits. And I stand firm: the format kwbybee has! Worry about lighting, posing, etc., etc., not format!

I've been paid to take those shots at innumerable high school and college events (but I had the advantage of f/2.8 on a 70-200 mm), and I can not improve upon the advice of Unclebe1! (You say lighting is not great - that's probably wildly over optimistic!) If you are shooting for the school you may be able to move around and get some shots from the foot of the stage with your short lens, or even the wings. If you have to pay and sit in a seat, your options are extremely limited.

If they allow flash photography you may be able to rent a strobe and go that way. (Used to be easy, now there's so few camera stores ...)

If you want to know what frustration is, show up to photograph a play on request, and have them elicit your promise to shoot sans flash, then during the performance every mother, uncle, et al, is flashing away, while you are struggling with the travails of available darkness. If you are in that position, make them announce "NO FLASH PHOTOGRAPHY" to everyone.

I've taken portraits with 8 x 10 and 4 x 5 large format, 6 cm x 7 cm medium format, 35 mm (FX) and DX. It ain't the format, it's the photographer! If choosing a lens for portraiture, a short telephoto is preferred. For your D7000, 50 mm (full frame 35 mm equivalent 75 mm) to 100 mm (150 mm equivalent) will do. Shorter tends to distort features - appears to enlarge the nose, etc. - longer puts photographer and subject in separate rooms.

Then the quality of the portrait is totally dependent upon the posing, lighting, and interaction of between the photographer and subject! Format doesn't mean a thing.

That's not the issue. The issue is how good the photographer can be! My advice was and is, go out and shoot in manual for a while to get the feel of what happens when you change aperture or shutter speed. THEN you choose aperture preferred or shutter preferred and let the camera's light sensing capability fine tune the exposure. But, I do not think you should turn the decision entirely over to program mode - the photographer should know why he might like an aperture of f/2.8 to blur the background, or f/16 for depth of field, or a shutter speed of 1/8 second to capture all the colors of a florescent display, or 1 second to allow the sense of motion in a waterfall.

When I was young and bought my first high tech film SLR, an Olympus which was aperture preferred auto plus full manual. a friend asked if I thought was smarter than the camera. I didn't realize it then, but the answer is, "Hell yes!"

I have never used the program mode. I'm sure it does a very good job, but I'm more sure that you can do a better one. Starting anew, and wanting to learn, I'd advise shooting in manual mode to get a better feel of what you're going to get in different situations. Digital is just like film, except that you have less latitude than you did with print film, particularly for overexposure.

And if you get an opportunity like SteveR at Donner Lake, use a tripod, a small aperture, and lower ISO!

Have fun!