Cynarina
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Bioprospector
Amazing!
Gary - I have been working on getting the depth of photos. Meaning, when taking a macro photo I only can get the lens to focus on a small amount of what I need it to. FOr example, when photographing an acan I cannot get from the top part of the polyp all the way to the mouth to be in focus. I can get the top part ver well or focus deeper to get the mouth.
I see that even with macros you get everything in focus and thats why I ask.
I shoot with a Canon Rebel Xti and use a 100mm f/2.8 macro lens.
Any advice would be helpful. Maybe this was the wrong thread to ask......
I could not resist, your photography is amazing!
Gary - I have been working on getting the depth of photos. Meaning, when taking a macro photo I only can get the lens to focus on a small amount of what I need it to. FOr example, when photographing an acan I cannot get from the top part of the polyp all the way to the mouth to be in focus. I can get the top part ver well or focus deeper to get the mouth.
I see that even with macros you get everything in focus and thats why I ask.
I shoot with a Canon Rebel Xti and use a 100mm f/2.8 macro lens.
Any advice would be helpful. Maybe this was the wrong thread to ask......
I could not resist, your photography is amazing!
OP
OP
Not a problem to ask in this thread and thanks for the compliment about my images.
What you are seeing when you focus on a coral is the depth of field at the lens' widest aperture, i.e., the shallowest DOF. In closeup/macro photography, that DOF will be very shallow/thin, as you have discovered. To get the necessary DOF, you need to close the aperture down considerably, meaning you'll have a much slower shutter speed, so you need a tripod. Try ISO 400 and an aperture of f/18 as a starting point. You'll need a good tripod and a remote release or use the camera timer. Use manual focus, as autofocus is too easily fooled.
You can try to see what your actual DOF is by using the depth of field preview button that is on your camera body on the left side at the base of the lens. Look through the viewfinder and push that button. It will close down the aperture to whatever setting you have it and you'll be able to see how much of your subject is in focus. I say try because the view often gets so dark you can't really see anything.
In macro photography, the amount of the subject that is in focus will be about 50% in front of and 50% behind the point at which you focus. With "normal" photography, the DOF is about a third in front of the focus point and two thirds behind.
The best way to understand what's happening with apertures and DOF is to set up your camera on a tripod, and focus on a subject. Take a picture at each full-stop aperture setting from wide open to the smallest aperture, i.e., a photo at f/2.8, f/4, f/5.6, f/8, f/11, etc. You'll have to adjust the shutter speed each time to keep the exposure on target. Then study the photos to see how the DOF changes.
Let me know if you have additional questions. It's often easier to help if you post a photo. You can post it in this thread or start a new one, or send it to me by e-mail and I'll try to help. [email protected]
Gary
What you are seeing when you focus on a coral is the depth of field at the lens' widest aperture, i.e., the shallowest DOF. In closeup/macro photography, that DOF will be very shallow/thin, as you have discovered. To get the necessary DOF, you need to close the aperture down considerably, meaning you'll have a much slower shutter speed, so you need a tripod. Try ISO 400 and an aperture of f/18 as a starting point. You'll need a good tripod and a remote release or use the camera timer. Use manual focus, as autofocus is too easily fooled.
You can try to see what your actual DOF is by using the depth of field preview button that is on your camera body on the left side at the base of the lens. Look through the viewfinder and push that button. It will close down the aperture to whatever setting you have it and you'll be able to see how much of your subject is in focus. I say try because the view often gets so dark you can't really see anything.
In macro photography, the amount of the subject that is in focus will be about 50% in front of and 50% behind the point at which you focus. With "normal" photography, the DOF is about a third in front of the focus point and two thirds behind.
The best way to understand what's happening with apertures and DOF is to set up your camera on a tripod, and focus on a subject. Take a picture at each full-stop aperture setting from wide open to the smallest aperture, i.e., a photo at f/2.8, f/4, f/5.6, f/8, f/11, etc. You'll have to adjust the shutter speed each time to keep the exposure on target. Then study the photos to see how the DOF changes.
Let me know if you have additional questions. It's often easier to help if you post a photo. You can post it in this thread or start a new one, or send it to me by e-mail and I'll try to help. [email protected]
Gary
Saltysteele
Bret
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imagine a line extending from a foot in front of you, to 100 feet. point A is at the beginning of the line, and point Z is at 100 feet.
first, focus on the edge of the subject that is closest to you.
now, if you use an fstop of 8, lets say, and the leading edge of the object is at point G, you'll get points G, H, some blurry I, less sharp J, and then blurry.
if you use fstop 16, focussing on G, you'll get G, H, I, J, blurry K, less sharp L.
fstop 28, you'll get G, H, I, J, K, L, M, N, blurry O, less sharp P.
that's how I remember it. the "higher" the fstop number, the more area will be in focus. the "lower" the fstop number, the less area will be in focus.
now, it's not as simple as that, but it's a place to start
first, focus on the edge of the subject that is closest to you.
now, if you use an fstop of 8, lets say, and the leading edge of the object is at point G, you'll get points G, H, some blurry I, less sharp J, and then blurry.
if you use fstop 16, focussing on G, you'll get G, H, I, J, blurry K, less sharp L.
fstop 28, you'll get G, H, I, J, K, L, M, N, blurry O, less sharp P.
that's how I remember it. the "higher" the fstop number, the more area will be in focus. the "lower" the fstop number, the less area will be in focus.
now, it's not as simple as that, but it's a place to start
Reef Pets
Bioprospector
This is great information!! I have played around with shooting for the past 4 months or so...... After messing with the f-stop over and over tonight and using what you guys have said I come to realize that there is no real way to fix how I have to photograph the coral.
I will have to take some photos tomorrow and show what I am working with. I grow the coral that I have in Rubermaids and the reflectors are about 20 inches over the tank. All of the photos are taken top down. With the Rubbermaids being solid, not glass no light can pass through them. With no light coming from the front or sides of the camera and the lens facing straight down the lens is not able to capture light like it would if I were shooting from the front side of a glass aquarium. And of course the light is over the camera when I take a photo.
So, with the lens not being able to capture light no matter what f stop I put it on the photo is still dark. To fix this issue I have been tricking the camera. Here is what I do..... I have a good tripod with a lateral arm and a remote. With my hand I move the light/reflector over so that the camera is reading little to no light, while the camera reads no light I push the remote button, after the shutter opens I then release the light to where it is directed on the coral and then of course the shutter closes. I am sure by tricking the camera I am destroying any chance of the correct DOF????
I know, this is an insane way to do it but its the only thing that works.
I think I am going to have to purchase a small tank to hook into the system for taking photos...... I have tried everything over the past several months and this is the only thing that I have figured out I can do to take a photo from top down with the light being over top of the camera.
I will have to take some photos tomorrow and show what I am working with. I grow the coral that I have in Rubermaids and the reflectors are about 20 inches over the tank. All of the photos are taken top down. With the Rubbermaids being solid, not glass no light can pass through them. With no light coming from the front or sides of the camera and the lens facing straight down the lens is not able to capture light like it would if I were shooting from the front side of a glass aquarium. And of course the light is over the camera when I take a photo.
So, with the lens not being able to capture light no matter what f stop I put it on the photo is still dark. To fix this issue I have been tricking the camera. Here is what I do..... I have a good tripod with a lateral arm and a remote. With my hand I move the light/reflector over so that the camera is reading little to no light, while the camera reads no light I push the remote button, after the shutter opens I then release the light to where it is directed on the coral and then of course the shutter closes. I am sure by tricking the camera I am destroying any chance of the correct DOF????
I know, this is an insane way to do it but its the only thing that works.
I think I am going to have to purchase a small tank to hook into the system for taking photos...... I have tried everything over the past several months and this is the only thing that I have figured out I can do to take a photo from top down with the light being over top of the camera.
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Saltysteele
Bret
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Gary, do you have a flash that you could mount on a separate tripod? Or, even a couple different light sources? Hmmmm...... but I guess you're trying to do it under tank lighting. Man, that's got to be tricky seeing through the light reflection, as well.
Let us know what you come up with
Hey, Gary (Parr)-
Here's a pic I took of my cynarina. Any tips? (besides that my sensor was dirty, Mike :tongue:; i bought some swabs and it's clean now
)
Let us know what you come up with
Hey, Gary (Parr)-
Here's a pic I took of my cynarina. Any tips? (besides that my sensor was dirty, Mike :tongue:; i bought some swabs and it's clean now
)
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OP
OP
Salty,
You must have done a Save for Web or something similar because it stripped out all of the EXIF data. Regardless, you need more DOF/smaller aperture/higher f/stop number to get more of the coral in focus. I'm going to assume you're shooting with a 100-mm macro lens with a maximum f/stop of f/42 or 45. Try an aperture in the mid 20s, say f/25, and focus about half way into the coral, i.e., not on the front edge. That should get most of the coral in focus. Play around from there until you get what you want. Don't use the smallest possible apertures because the image will start to degrade with some lenses. I don't see it much with my 180 at small apertures, but have seen the image get pretty crappy because light entering that small hole starts banging around in the lens cylinder before it gets to the sensor.
As for your image, you definitely need to make a levels adjustment to get the contrast/colors to pop a little more. I have no idea what the actual coral looks like, but I took a stab at it to at least liven up what you posted. I was working with a the small jpg you posted, so you'll get better results with the original. I'm assuming you know how to make levels adjustments. If not, let me know. My effort is below.
I didn't clone out the dust spots.
I highly recommend getting an Arctic Butterfly brush for dust spots. Best investment I've ever made for cleaning sensors. I rarely use the wet swabs anymore.
Gary
You must have done a Save for Web or something similar because it stripped out all of the EXIF data. Regardless, you need more DOF/smaller aperture/higher f/stop number to get more of the coral in focus. I'm going to assume you're shooting with a 100-mm macro lens with a maximum f/stop of f/42 or 45. Try an aperture in the mid 20s, say f/25, and focus about half way into the coral, i.e., not on the front edge. That should get most of the coral in focus. Play around from there until you get what you want. Don't use the smallest possible apertures because the image will start to degrade with some lenses. I don't see it much with my 180 at small apertures, but have seen the image get pretty crappy because light entering that small hole starts banging around in the lens cylinder before it gets to the sensor.
As for your image, you definitely need to make a levels adjustment to get the contrast/colors to pop a little more. I have no idea what the actual coral looks like, but I took a stab at it to at least liven up what you posted. I was working with a the small jpg you posted, so you'll get better results with the original. I'm assuming you know how to make levels adjustments. If not, let me know. My effort is below.
I didn't clone out the dust spots.
I highly recommend getting an Arctic Butterfly brush for dust spots. Best investment I've ever made for cleaning sensors. I rarely use the wet swabs anymore.Gary
OP
OP
Gary (Reefpets),
I think you're making things much too complicated. The shots I posted to start this thread are top-down shots with a horizontal arm and the camera hanging over the tank. I've done many top-down shots in Rubbermaid tubs. With top-down shots, you're biggest issue is surface reflection from the lights. Don't do anything with the lights. Just move the corals you want to photograph to an area along the edge of the tank that doesn't have any reflection from the fixture. If you stand on a stool and look straight down, so you're viewing the water surface from the fixture perspective, you'll see what areas don't have reflections. Those are your shooting areas. Move the corals to one of those areas, give them a chance to inflate again, and take your pictures. You'll get more than enough light spill from the fixture to get a nice exposure. Shoot in manual mode so the camera isn't fooled and turn off autofocus. You will likely end up with a relatively slow shutter speed, but it doesn't matter because the coral isn't going anywhere. Be sure that all water flow is off.
The shots that started this thread were done at 0.8 sec. @ f/18 and ISO 400, using a 180-mm macro lens.
Don't try to add a flash or supplemental lighting because you'll simply be adding more surface reflection.
Gary
I think you're making things much too complicated. The shots I posted to start this thread are top-down shots with a horizontal arm and the camera hanging over the tank. I've done many top-down shots in Rubbermaid tubs. With top-down shots, you're biggest issue is surface reflection from the lights. Don't do anything with the lights. Just move the corals you want to photograph to an area along the edge of the tank that doesn't have any reflection from the fixture. If you stand on a stool and look straight down, so you're viewing the water surface from the fixture perspective, you'll see what areas don't have reflections. Those are your shooting areas. Move the corals to one of those areas, give them a chance to inflate again, and take your pictures. You'll get more than enough light spill from the fixture to get a nice exposure. Shoot in manual mode so the camera isn't fooled and turn off autofocus. You will likely end up with a relatively slow shutter speed, but it doesn't matter because the coral isn't going anywhere. Be sure that all water flow is off.
The shots that started this thread were done at 0.8 sec. @ f/18 and ISO 400, using a 180-mm macro lens.
Don't try to add a flash or supplemental lighting because you'll simply be adding more surface reflection.
Gary
Nice shots.
To deal with surface refraction for top down shots just buy or make a surface viewer out of acrylic. Try to make it deep like 5"x5"x5" so the lens can fit in it and the reflections don't get in the viewer.
To deal with surface refraction for top down shots just buy or make a surface viewer out of acrylic. Try to make it deep like 5"x5"x5" so the lens can fit in it and the reflections don't get in the viewer.
OP
OP
I've tried a couple of those things and I feel like it's one more thing to deal with and I greatly fear swamping and getting my lens soaked. I also seemed to be sacrificing quite a bit of clarity/sharpness. Getting tripod, horizontal arm, camera, viewing box, and remote all coordinated, while trying to focus and compose was just too much hassle. I'd be curious to see/hear about your setup.
Gary
SaraB
2500 Club Member
:tongue: Maybe! I said it would involve a free meal at your favorite mexican restaurant too ... to discuss photoshop. :bigsmile:
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Bioprospector
Gary - Thanks for the advice! Would make the photo dark when I shooot how I explained? I have tried every f/stop and ISO with combinations of each. If you shoot how you explain they photos come out extremely dark.
I will take some phots this evening. I will not alter them in any way except to resize so that they will fit in the forum.
I am considering setting up a photo tank....
I will take some phots this evening. I will not alter them in any way except to resize so that they will fit in the forum.
I am considering setting up a photo tank....
OP
OP
I wish I lived near you. I'd run over and we'd have this fixed in about 10 min. Take a couple of shots, post them, and then call me. I'll PM you my phone number. I'll be around all day.
I had a photo tank set up at a shop I was helping (they've since gone out of of business). It worked well, but water had to be pumped from the tank that was housing the corals and the corals had to be moved, then I had to wait for them to readjust to the new environment. It took a lot of time for very little gain.
Gary
I had a photo tank set up at a shop I was helping (they've since gone out of of business). It worked well, but water had to be pumped from the tank that was housing the corals and the corals had to be moved, then I had to wait for them to readjust to the new environment. It took a lot of time for very little gain.
Gary
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Saltysteele
Bret
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Gary, yes, yours looks much better I need help with contrast, for sure. Would you mind if I sent you the RAW file? I'm at work right now, so wouldn't be able to get it to you tonight.
I love what you've done with the small jpeg, yes it was saved for web.
I'm shooting with a Canon 20D, and Canon 100mm f2.8. Although, I think aperature only goes to 36 or 32?
I need help with contrast, for sure. Would you mind if I sent you the RAW file? I'm at work right now, so wouldn't be able to get it to you tonight.I love what you've done with the small jpeg, yes it was saved for web.
I'm shooting with a Canon 20D, and Canon 100mm f2.8. Although, I think aperature only goes to 36 or 32?
OP
OP
Gary, yes, yours looks much better
I love what you've done with the small jpeg, yes it was saved for web.
I'm shooting with a Canon 20D, and Canon 100mm f2.8. Although, I think aperature only goes to 36 or 32?
Sure, send it, I'll take a look. [email protected]. If you have trouble sending by e-mail, let me know and I'll give you an ftp address.
Gary
OP
OP
Timothy, nice timing.
Though the image is a little dark, those are some intense, deep colors. Is that the way the coral looks?
Are you using a tripod? Your images seem to have a slight blur to them, or maybe they just need sharpening?
Gary
Though the image is a little dark, those are some intense, deep colors. Is that the way the coral looks?
Are you using a tripod? Your images seem to have a slight blur to them, or maybe they just need sharpening?
Gary
