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Vacation Photography: Let's Visit a Cave
30/06/11 15:15
Vacation Photography: Let's Visit a Cave
Mammoth Cave National Park, KY, USA
One my most fond memories of childhood was visiting Mammoth Cave National Park. We went every summer and I took every tour of the cave that they would let a kid take. So, as an adult I wanted my kids to have the same great cave experience and this year we went to the cave. It was so interesting to hear the Ranger tell the tour group the same thing that the Park Rangers said to the groups as a child. He said, “If you want a photo of the inside of the cave then buy a postcard.” No, he was not trying to sell post cards he was stating a fact. The fact is, it is hard to take a good photograph of the inside of a cave and especially hard to take those photos when you are on a tour.
ISO 800, 50mm, f2, 1/60s
Safety and Courtesy
Before I start talking about how to get a great cave photo let me talk about safety and courtesy on a cave tour.
I will talk about safety first. Never walk and take photos at the same time while in a cave. Caves have uneven ceilings, floors, and walls. Caves are poorly lit and at times caves are wet. These things all lead to one certain conclusion and that is no matter how well you walk in your own home, if you have a camera up to your eye you may end up giving yourself a concussion, contusion, or being cussed at by another cave customer.
Courtesy is another factor in getting good cave photos and perhaps the best way to be courteous to others and the Rangers is to stay with the group and in particular stay in the front of the group. During walking tours in a cave or in the woods, groups tend to act like an accordion. They stretch and contract. If you are in the front you will need to stop from time to time to let people catch up. These are perfect times to take photographs without feeling rushed and without holding up the group. The people in the back of the group always feel rushed to catch up with the group and being rushed does not make for good photography.
Point and Shoot
If you have a standard run of the mill point and shoot camera the ranger is most likely correct: you need to just buy a post card. These inexpensive cameras are not well suited to cave photography. Most point and shoot digital cameras have a very small sensor and that small sensor translates into very little light being recorded on the image sensor. These cameras are also primarily automatic focus. Automatic Focus is next to useless in near complete darkness. If you have a bridge camera, in other words if your camera will shoot in RAW mode, has manual ISO and Manual focusing, you can give the photos a try but I am not making any promises that you will get the results you are looking for in your cave photographs. Unfortunately cave photography is an advanced technique and if you can do it with a point and shoot camera (yes, it can be done) then you don’t need this article. However if you have a DSLR or at least a bridge camera, why not use this as an opportunity to push your skill set and get in there and take some photos you will remember.
Hardware
The hardware you will need is pretty strait-forward. You need a DSLR camera, and a prime lens (otherwise known as a fixed focal length lens- for a APS-C I recommend a 28mm or 25mm lens with at least an f2.8 and for a full frame camera I recommend a 50mm f1.4 lens) preferably optically stabilized.
Camera Settings
ISO
I know I have already mentioned it but I feel like I should say it again, caves are dark. Since caves are so dark very little light is going to reach the sensor of the camera and that must be taken into consideration when shooting in a cave. The first thing you want to do is set your ISO on your camera to a high ISO setting. Depending on the ambient lighting within the cave, this might mean ISO 400 up to ISO 3200 or even higher. Just remember that the higher the ISO number the more noise/grain on the final photograph and the faster the shutter speed can be on your camera. In other words take a few shots to see what the slowest shutter speed is at which you can hold the camera steady. Optical stabilization in your camera or lens will help extend this time significantly.
ISO 12800, 50mm, f2.8, 1/8s
Ranger Steve Kister conducting a tour of Mammoth Cave. He is demonstrating what a single flame of light looks like in total darkness.
Notice the grainy nature of this photograph. It was taken with only the flame in his hand illuminating the scene. This required an extremely high ISO and as such introduced a lot of noise into the shot. If I could have used a tripod in the cave I could have reduced the ISO and increased the clarity of the photo.
Depth of Field (DOF) or fstop
Depth of field or fstop is a tricky thing in a cave and has to be taken seriously. You might think that I would recommend making the aperture of the lens as big as you can get it. A big aperture does mean more light getting to the sensor and faster shutter speeds. It also means very narrow depth of field and more often than not a blurry photograph. If you had all the time in the world and could somehow sneak in a tripod, you could calculate your depth of field and determine an ideal fstop to accommodate the lighting. Calculating depth of field requires measuring front and back distances of the focal plain, taking light readings, and (most of all) time. Time is one thing you do not have a lot of on a cave tour. I have found that setting my aperture to f 2.8 is a fair compromise between depth of field and my ability to hold the camera steady during shooting.
Shutter Speed
Shutter speed is also tricky. I shoot full manual or aperture priority mode in low light situations. I always start out shooting a few shots on aperture priority mode. I want to get a feel for what the camera thinks is a good shutter speed. Now is a good time to mention that you may want to set your camera’s metering mode to spot metering. This will allow you to take more precise measurements of the light part of the photographs and not worry about the unlighted portions of the frame. Otherwise you may actually over-expose the lighted areas. I have found that I can hand hold my camera at about 1/8th of a second shutter speed, however, your mileage may vary.
Manual Focus
Manual focusing is a must in extreme low light situations. Automatic focusing relies on contrast to work properly and contrast relies on light. If you rely on auto-focus you will find that your camera is searching for focus instead of getting the shot. Manual focus is pretty easy with a little practice and will have you hanging a print on the wall instead of trying to sharpen the image enough in post processing to at least share it on Facebook.
Conclusion
ISO, DOF, Shutter speed, and Manual Focus . Yep, those are the three elements of taking photos in a cave. Go out there and take some great shots.
Woah! Woah! Woah! What about using a flash to just light up the cave?
Flash
Using a flash in a cave is a great way to get some great shots. Those postcards the Ranger encouraged us to buy were all shot with flash units or at least some sort of external and additional lighting. I guess I really should have talked about flash under “Courtesy,” but I wanted to save it for last. A flash is impolite in a cave. Let me rephrase that a flash is just plain rude to use on a cave tour. Your built in flash is too low powered to really illuminate anything much in the cave and a high guide number external flash is going to blind everyone else on the tour every time you take a photo. Just think about it, it is dark in a cave and people’s eyes adjust to the dark. When you fire the “Big” flash you will blind someone else on the tour and that cussing I told you about might be coming your way; and if you really make someone mad the concussion might be on it’s way as well.
The Real Conclusion
Cave photography, while an advanced technique, is in reality very strait forward. The following summary is really all you need to know.
I hope if you make it to a cave this summer that this article helps you bring home some great photographs. After you get out of the cave, don’t forget to take a few photos of the surrounding area, often these are as pretty or prettier than the cave itself. I will leave you with a photo of the forest around Mammoth Cave.
-- Enjoy.
The forest surrounding the natural entrance to Mammoth Cave.
For a gallery of cave photos click here: Cave Photos
Mammoth Cave National Park, KY, USA
One my most fond memories of childhood was visiting Mammoth Cave National Park. We went every summer and I took every tour of the cave that they would let a kid take. So, as an adult I wanted my kids to have the same great cave experience and this year we went to the cave. It was so interesting to hear the Ranger tell the tour group the same thing that the Park Rangers said to the groups as a child. He said, “If you want a photo of the inside of the cave then buy a postcard.” No, he was not trying to sell post cards he was stating a fact. The fact is, it is hard to take a good photograph of the inside of a cave and especially hard to take those photos when you are on a tour.
ISO 800, 50mm, f2, 1/60s
Safety and Courtesy
Before I start talking about how to get a great cave photo let me talk about safety and courtesy on a cave tour.
I will talk about safety first. Never walk and take photos at the same time while in a cave. Caves have uneven ceilings, floors, and walls. Caves are poorly lit and at times caves are wet. These things all lead to one certain conclusion and that is no matter how well you walk in your own home, if you have a camera up to your eye you may end up giving yourself a concussion, contusion, or being cussed at by another cave customer.
Courtesy is another factor in getting good cave photos and perhaps the best way to be courteous to others and the Rangers is to stay with the group and in particular stay in the front of the group. During walking tours in a cave or in the woods, groups tend to act like an accordion. They stretch and contract. If you are in the front you will need to stop from time to time to let people catch up. These are perfect times to take photographs without feeling rushed and without holding up the group. The people in the back of the group always feel rushed to catch up with the group and being rushed does not make for good photography.
Point and Shoot
If you have a standard run of the mill point and shoot camera the ranger is most likely correct: you need to just buy a post card. These inexpensive cameras are not well suited to cave photography. Most point and shoot digital cameras have a very small sensor and that small sensor translates into very little light being recorded on the image sensor. These cameras are also primarily automatic focus. Automatic Focus is next to useless in near complete darkness. If you have a bridge camera, in other words if your camera will shoot in RAW mode, has manual ISO and Manual focusing, you can give the photos a try but I am not making any promises that you will get the results you are looking for in your cave photographs. Unfortunately cave photography is an advanced technique and if you can do it with a point and shoot camera (yes, it can be done) then you don’t need this article. However if you have a DSLR or at least a bridge camera, why not use this as an opportunity to push your skill set and get in there and take some photos you will remember.
Hardware
The hardware you will need is pretty strait-forward. You need a DSLR camera, and a prime lens (otherwise known as a fixed focal length lens- for a APS-C I recommend a 28mm or 25mm lens with at least an f2.8 and for a full frame camera I recommend a 50mm f1.4 lens) preferably optically stabilized.
Camera Settings
ISO
I know I have already mentioned it but I feel like I should say it again, caves are dark. Since caves are so dark very little light is going to reach the sensor of the camera and that must be taken into consideration when shooting in a cave. The first thing you want to do is set your ISO on your camera to a high ISO setting. Depending on the ambient lighting within the cave, this might mean ISO 400 up to ISO 3200 or even higher. Just remember that the higher the ISO number the more noise/grain on the final photograph and the faster the shutter speed can be on your camera. In other words take a few shots to see what the slowest shutter speed is at which you can hold the camera steady. Optical stabilization in your camera or lens will help extend this time significantly.
ISO 12800, 50mm, f2.8, 1/8s
Ranger Steve Kister conducting a tour of Mammoth Cave. He is demonstrating what a single flame of light looks like in total darkness.
Notice the grainy nature of this photograph. It was taken with only the flame in his hand illuminating the scene. This required an extremely high ISO and as such introduced a lot of noise into the shot. If I could have used a tripod in the cave I could have reduced the ISO and increased the clarity of the photo.
Depth of Field (DOF) or fstop
Depth of field or fstop is a tricky thing in a cave and has to be taken seriously. You might think that I would recommend making the aperture of the lens as big as you can get it. A big aperture does mean more light getting to the sensor and faster shutter speeds. It also means very narrow depth of field and more often than not a blurry photograph. If you had all the time in the world and could somehow sneak in a tripod, you could calculate your depth of field and determine an ideal fstop to accommodate the lighting. Calculating depth of field requires measuring front and back distances of the focal plain, taking light readings, and (most of all) time. Time is one thing you do not have a lot of on a cave tour. I have found that setting my aperture to f 2.8 is a fair compromise between depth of field and my ability to hold the camera steady during shooting.
Shutter Speed
Shutter speed is also tricky. I shoot full manual or aperture priority mode in low light situations. I always start out shooting a few shots on aperture priority mode. I want to get a feel for what the camera thinks is a good shutter speed. Now is a good time to mention that you may want to set your camera’s metering mode to spot metering. This will allow you to take more precise measurements of the light part of the photographs and not worry about the unlighted portions of the frame. Otherwise you may actually over-expose the lighted areas. I have found that I can hand hold my camera at about 1/8th of a second shutter speed, however, your mileage may vary.
Manual Focus
Manual focusing is a must in extreme low light situations. Automatic focusing relies on contrast to work properly and contrast relies on light. If you rely on auto-focus you will find that your camera is searching for focus instead of getting the shot. Manual focus is pretty easy with a little practice and will have you hanging a print on the wall instead of trying to sharpen the image enough in post processing to at least share it on Facebook.
Conclusion
ISO, DOF, Shutter speed, and Manual Focus . Yep, those are the three elements of taking photos in a cave. Go out there and take some great shots.
Woah! Woah! Woah! What about using a flash to just light up the cave?
Flash
Using a flash in a cave is a great way to get some great shots. Those postcards the Ranger encouraged us to buy were all shot with flash units or at least some sort of external and additional lighting. I guess I really should have talked about flash under “Courtesy,” but I wanted to save it for last. A flash is impolite in a cave. Let me rephrase that a flash is just plain rude to use on a cave tour. Your built in flash is too low powered to really illuminate anything much in the cave and a high guide number external flash is going to blind everyone else on the tour every time you take a photo. Just think about it, it is dark in a cave and people’s eyes adjust to the dark. When you fire the “Big” flash you will blind someone else on the tour and that cussing I told you about might be coming your way; and if you really make someone mad the concussion might be on it’s way as well.
The Real Conclusion
Cave photography, while an advanced technique, is in reality very strait forward. The following summary is really all you need to know.
- Be Polite: Stick to the front of the group, stop to take a photo, and turn off the flash.
- Image Stabilization: Turn it on.
- ISO: Set the highest ISO that you need to get the shot but remember that high ISO equals added noise in the photo.
- Depth of Field: Bigger is better to a point. f2.8 works best for me but you may find that you can get acceptable images at f1.2 or f5.6. Try it out to see what works for you.
- Shutter Speed: Make it as slow as you can without blurring the shot.
- Manual Focus: Turn off the autofocus in low light.
I hope if you make it to a cave this summer that this article helps you bring home some great photographs. After you get out of the cave, don’t forget to take a few photos of the surrounding area, often these are as pretty or prettier than the cave itself. I will leave you with a photo of the forest around Mammoth Cave.
-- Enjoy.
The forest surrounding the natural entrance to Mammoth Cave.
For a gallery of cave photos click here: Cave Photos