Bike tour

Will be going to Mammoth Cave next month and would like to know what settings and lens to use. I have a Cannon Rebel T3i.

Elliott Design Loc: West Tennessee

Nice camera, I use that myself, it's not always what you use but how you use it. Don't rely on your auto settings for low light, practice in manual mode and learn to get acceptable exposures in a dimly lit room of your house or garage, think using two 40 watt bulbs as your light source in a 12' x 12' area. Set your ISO to a maximum 1600, anything over this and the T3i gets really grainy. A good 50mm 1.4 or 1.8 will work, the lighting is quite low in the caves, your kit lens will work with it's 3.5 f-stop but not as well as the faster lens. A fast lens will have you at 1/80 and less shutter speed and with the 3.5 lens you'll be at 1/25 and less, so any movement of the camera or subjects at these speeds will be blurred. A tripod would help a lot but opt for a monopod, it's less troublesome carrying. On camera flash will look horrible in most shots and off camera flash will be hard to handle unless you have some help. You'll also need a plastic bag or something easy to place over the camera, Mammoth Cave is VERY damp in places with water dripping from the ceiling. It will take a few minutes for you lens to acclimate to the high humidity, the first few shot immediately in may have a fog. Stay at the back end of the line and shoot behind you, you'll need slow shutter speed and wide open aperture and a steady brace with your monopod but you can come away with some neat shots if you take your time and understand your camera settings before going in. A little PP in your editing software can help with all but the worst exposures. Have fun, be careful, and be sure to ask the guide or at the ticket gate if can use a flash in the caves, some don't allow it because it can create problems for their visitors, once your eyes get accustomed to the low lighting a sudden flash from a camera can flashblind someone and cause them to fall or bump their head. Caves are dangerous places and we don't need anyone getting hurt so you can get a picture, that is the reason I say you should learn to shoot manual and be sure to leave the flash turned off in the camera menu so it won't pop up on its own.

jerryc41 Loc: Catskill Mts of NY

Thanks. Good advice, especially about shooting behind you and having protection from water. I'm surprised you recommend against flash. I'm several months late in getting to Howe Caverns, in NY.

Here are some references I found.

http://www.ephotozine.com/article/a-shot-in-the-dark---guide-to-cave-photography-4680
http://www.goodearthgraphics.com/showcave/photo.html
http://digital-photography-school.com/14-tips-for-cave-photography
http://www.weatherfriend.com/travel/txcave/cave_photography.htm
http://museumca.org/caves/onli_photo.html
http://www.shutterbug.com/content/cave-photography-color-gear-and-light-painting-underground-style

Bike tour

Thanks I will try to practice this weekend in a low light house. The plastic bag advice will be followed. Mammoth Cave has a photo tour for those that want to take pictures.

Elliott Design Loc: West Tennessee

Bike Tour, the photo tour sounds great, been years since I was at the caves, I was shooting film back then on a 35mm Yashica. A friend an I used to ride our bikes up to Horse Cave, KY and camp out once a year, ride around in the early and late of the day when it was cool but head for the area caves in the heat of the day.

Jerryc41, good links, we can all pick up some great tips from those.

RaydancePhoto

Very good advice from Elliott Design. One more thing, if you shoot in RAW, you can underexpose 2 stops and make that up in PP. I shoot low light quite a bit and this method really helps get the SS up.

robert-photos Loc: Chicago

Raydance,

If you underexpose by 2 stops and correct in ACR you introduce approximately the same (or even more) amount of noise as if you increased your ISO by two stops and exposed the photo properly in camera. There really is little difference except that the properly exposed photo, depending on your camera, may be less noisy in the shadows than the post processed photo. IMAO you should always properly expose even if it means boosting the ISO rather than depend on exposure correction in post.

If you are an unbeliever do your own experiment. Shoot anything (with highlights and shadows) properly exposed at ISO 1600, keep the shutter speed and aperture the same and reduce the ISO to 400 and then only boost the exposure by 2 stops in ACR. Compare the results.

There are also long techinical discussions of this on the web:
http://forums.dpreview.com/forums/read.asp?forum=1021&message=21928279
http://www.dgrin.com/archive/index.php/t-65352.html

DavidT Loc: Maryland

The problem with shooting in caves is that, in many cases, you are not allowed to bring a tripod. And, if you did you would need time to set up and avoid shooting the people with the group. I also found that flash just doesn't make it. The best solution is to lean your camera against a wall (or rock) at a long exposure (I would even suggest Auto (gasp!) and hope for the best.

Bike tour

Thanks for all the info. Will try some shot shots in my daughter's barn this weekend with her horses.

tainkc Loc: Kansas City

Wow! I was hoping that I may be of some assistance since I was in War Eagle cavern just this Last October and it was the first time doing serious shooting with my new camera and I had a bunch of great shots.

Turns out that after looking at my meta data, I was all over the board. I guess I must have been really experimenting. I was using ISO's fro 100 up to 6400. Kept the apertures down to around F4.5 though. I did notice that some of my shots were shot with shutter speeds of 1/25 sec. @ ISO 6400 and they are as sharp as a tack with no noise. But my camera can do this and so can I since I am not an old fart just yet. I did not have a monopod or a tripod. Nothing to lean against. A lot of them were shot with a flash. Everything I shot was in manual mode. For not knowing the camera, I did alright.

I have been on several cave tours including Mammoth Caves and they do have guide lighting in them so you should do just fine. Practicing in the barn sounds like a great idea though. I also just looked back again and noticed that I took a few pix looking up some chimneys with just ambient light from the guide lights which were nothing more than 100 watt bulbs in trouble lights. No flash. These shot turned out very good also. My settings were F7.1 @ 1/100th sec. @ ISO 25,600 with very little noise. Go figure.

Experiment_626

Does your camera have an auto-bracketing setting? If so, you might want to try using it.

I recently shot some cave photos in a small local state park, one which features the only air-filled caves in Florida that are open to the general public. I used a Nikon D300 and a Tamron 17-50 f/2.8 with optical stabilization. No tripods are permitted on the cave tour. They're a tripping hazard, plus there is often not enough room to set one up and even if there were, there really isn't enough time. I do hope to go back at some point (and bring along one of my ex-president friends -- the ones with the green faces) to maybe arrange for a private tour for shooting HDR.

Anyway, this particular cave is pretty dark, I suppose. I shot at ISO 3200 and f/2.8 and got exposure times of between 1/20th and 1/60th for most of my shots, with the majority being closer to 1/20th. Most of them came out acceptably sharp thanks to the stabilization. I tried a few shots using flash; I think if I had to try that again today I would set flash compensation to maybe -2EV. A few of my shots had a light source in the frame, and I think those were subsequently under exposed for the rest of the scene because of it. But the thing is, those frames probably did the best job of duplicating how the light level inside the cave actually appears to a visitor. The other shots look nice but appear brighter overall than reality. THAT is why I asked about bracketing; if you can can set your camera to autobracket one- and two-stop underexposed images in addition to the meter's recommended exposure, you might find you like some the underexposed ones better. If not, you haven't lost anything. Probably not useful to try to set an overexposed image into the mix, since you're going to be right at the limit of your camera's low-light capability as it is.

You can see a set of some of the images I made at http://www.flickr.com/photos/54355875@N04/sets/72157629654078023/ The three shots of my two boys are the ones I mentioned above.

SSB