Lighting for macro photography of fern gametophytes
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Have you considered working from video? See for example http://www.photomacrography.net/forum/v ... hp?t=11130 and notice the specs:
But I'm thinking that HD resolution in exchange for no wilting would be a good tradeoff for you.
These days I would use ffmpeg to convert video to still frames for stacking. Otherwise things would be pretty much the same.
--Rik
Obviously the quality of video frames is less than good single frames.Camera: Canon T1i.
Objective: Nikon CF E 4X NA 0.1, 160/- on 165 mm total extension.
Rail speed: 0.4 mm per second (20 µm per frame at 20 fps).
Total acquisition time, 45 seconds at 1920x1080.
Acquisition time used in final stack, 2.5 seconds.
But I'm thinking that HD resolution in exchange for no wilting would be a good tradeoff for you.
These days I would use ffmpeg to convert video to still frames for stacking. Otherwise things would be pretty much the same.
--Rik
Jen,
Perhaps you may have to shoot video stacks, as Rik mentioned. But if you can look at gametophytes for a long time under a dissecting scope, I wouldn't give up on stacked stills just yet.
I do wonder if the humidity in your shooting environment is high enough. You mentioned shooting an aquarium. How about making a mini aquarium out of microscope slides, with a cover glass for the front? These are easy to make, in combination with silicone adhesive caulking. (I'd be looking at 3x3" slides for this.) Then perhaps put a layer of fine pebbles in the bottom, and add water between the pebbles. Perhaps also mist the inside surfaces of the mini aquarium, other than the "shoot through" side. This might permit a micro-environment in which your gametophytes maintain turgor
Also, if you can stabilize your system enough to work with continuous light, you can shoot with extremely dim light. For reasons unrelated to shrinking ferns, I use 8-second exposures with continuous light. Such long exposures require that I shoot in a dark room, and close the irises on my illuminators so much that I can barely see my subjects. (I'll have done my framing, focusing, and stack programming with the irises open) Under such dim lighting, would the gametophyte maintain turgidity?
Couple of thoughts:
I've noticed that even small plants use up water rapidly when shooting. Are you sure that your initial wetting of the specimen doesn't dry out? Could you rig up a drip system to keep your gametophyt constantly hydrated?
Your experiment with three flashes bounced off a reflective circle strikes me as the worst of all worlds: A bring light source (the reflective circle), quite far from the fern, is likely to deliver harsh light that will probably not permit full resolution photographs. The three flashes near the plant aren't pointing at it, but the bodies of the flashes are still exuding heat in all directions. Could heat emitted have effected your fern?
BTW, I greatly appreciate if you'd share in private conversation what tips you learned on growing fern gametophytes. My botany mentor did this, but as I was working on other things, I paid only a bit of attention. It would be fun to do now.
Cheers,
--Chris S.
Perhaps you may have to shoot video stacks, as Rik mentioned. But if you can look at gametophytes for a long time under a dissecting scope, I wouldn't give up on stacked stills just yet.
I do wonder if the humidity in your shooting environment is high enough. You mentioned shooting an aquarium. How about making a mini aquarium out of microscope slides, with a cover glass for the front? These are easy to make, in combination with silicone adhesive caulking. (I'd be looking at 3x3" slides for this.) Then perhaps put a layer of fine pebbles in the bottom, and add water between the pebbles. Perhaps also mist the inside surfaces of the mini aquarium, other than the "shoot through" side. This might permit a micro-environment in which your gametophytes maintain turgor
Also, if you can stabilize your system enough to work with continuous light, you can shoot with extremely dim light. For reasons unrelated to shrinking ferns, I use 8-second exposures with continuous light. Such long exposures require that I shoot in a dark room, and close the irises on my illuminators so much that I can barely see my subjects. (I'll have done my framing, focusing, and stack programming with the irises open) Under such dim lighting, would the gametophyte maintain turgidity?
Couple of thoughts:
I've noticed that even small plants use up water rapidly when shooting. Are you sure that your initial wetting of the specimen doesn't dry out? Could you rig up a drip system to keep your gametophyt constantly hydrated?
Your experiment with three flashes bounced off a reflective circle strikes me as the worst of all worlds: A bring light source (the reflective circle), quite far from the fern, is likely to deliver harsh light that will probably not permit full resolution photographs. The three flashes near the plant aren't pointing at it, but the bodies of the flashes are still exuding heat in all directions. Could heat emitted have effected your fern?
BTW, I greatly appreciate if you'd share in private conversation what tips you learned on growing fern gametophytes. My botany mentor did this, but as I was working on other things, I paid only a bit of attention. It would be fun to do now.
Cheers,
--Chris S.
Thanks Chris,
I see what you mean, if it worked under my microscope then this should be okay too. I think I used two swan neck illuminators in those days. I'm not sure if that was different in some way. Oddly my supervisor didn't though for photography. He used two massive lights and a fish tank.
That's a great idea about the tiny microscope slide fish tank. I'll have a think about that.
The technique I use to grow ferns is written up as part of my microscope write-up as it's really one of the hardest parts. This is it:
https://github.com/BioMakers/23_Focus-s ... ngFerns.md
Let me know if you have any questions. The world can only be made better by having more fern growers in it. :-)
Thanks!
Jen
I see what you mean, if it worked under my microscope then this should be okay too. I think I used two swan neck illuminators in those days. I'm not sure if that was different in some way. Oddly my supervisor didn't though for photography. He used two massive lights and a fish tank.
That's a great idea about the tiny microscope slide fish tank. I'll have a think about that.
The technique I use to grow ferns is written up as part of my microscope write-up as it's really one of the hardest parts. This is it:
https://github.com/BioMakers/23_Focus-s ... ngFerns.md
Let me know if you have any questions. The world can only be made better by having more fern growers in it. :-)
Thanks!
Jen
The other thing that a friend has just pointed out is that my previous good photo was shot without flash at all and just on long exposures.
That was when I was working with the fern mounted on a flatbed scanner and the camera was not physically attached to the scanner at all so perhaps the vibration of the camera was kept away from the fern.
Currently the camera is strongly tethered to the base on which the subject stands, so all vibration is going straight through it.
I wonder if I should disconnect them and try without flash. That would be easy as I just need to turn the camera round on its stand and stand the fern on the floor instead of the wooden board.
That was when I was working with the fern mounted on a flatbed scanner and the camera was not physically attached to the scanner at all so perhaps the vibration of the camera was kept away from the fern.
Currently the camera is strongly tethered to the base on which the subject stands, so all vibration is going straight through it.
I wonder if I should disconnect them and try without flash. That would be easy as I just need to turn the camera round on its stand and stand the fern on the floor instead of the wooden board.
If you use your Canon (not using flash) from Live View, as discussed "above"(!) somewhere, vibration from the camera is unlikely to be a problem. Vibration from any floor can be a problem though, so I'd keep camera and subject on the same board.
If you leave the spore undisturbed, growing in the soil, does it wilt when you fire a flash at it?
If you leave the spore undisturbed, growing in the soil, does it wilt when you fire a flash at it?
Chris R
Hi Chris,
I don't dare to fire a flash at the pot of spores as I only have three pots and a 4 week deadline and they take several weeks to germinate.
I am doing all the photography on live view. I must recheck to see what the vibration situation is. I may not have been using live view when I tested that.
I've bought a stage micrometer to photograph to see what the depth of field is. That will be fun. :-)
I don't dare to fire a flash at the pot of spores as I only have three pots and a 4 week deadline and they take several weeks to germinate.
I am doing all the photography on live view. I must recheck to see what the vibration situation is. I may not have been using live view when I tested that.
I've bought a stage micrometer to photograph to see what the depth of field is. That will be fun. :-)
Nothing special really-
Picture is a couple of years old. That's meant to be a bug. It works for mosses.
Greenish at left is eg Mitutoyo objective, with paper wrapped around. Overlap attenuates more light, but it reflects around inside anyway. Black thing means light source - I used a flash.
Snoot near the ground holds humidity in, breezes out.
I expect you used a water cup - easier to attach a tube of paper!
Chris R
Hi Chris,
Yes I see what you mean. :-) Thanks.
I had sort of thought about doing that with a freezer bag, but I was unsure of the effects of high humidity on the objective. Someone told me that they are vulnerable to fumes (superglue fumes specifically) and it made me wonder what other well meaning things I could do that would the objective off.
Yes I see what you mean. :-) Thanks.
I had sort of thought about doing that with a freezer bag, but I was unsure of the effects of high humidity on the objective. Someone told me that they are vulnerable to fumes (superglue fumes specifically) and it made me wonder what other well meaning things I could do that would the objective off.
Hello!
I didnt read the whole thread as it have 30 pages already, so i apologize if some of those are not helpfull, but here are just a few ideas to consider:
-Im doing kinda similar thing for a living. Part of my job is photographing fern explanatats, and what i've found out is that they just hate flash lamps, while they can stand hours of continous light (despite emmiting quite a lot of heat), so i ended up with using 6 Jansjo lamps diffused through lab paper with shutter times ranging from 1/5 - 1/30 with EFSC on, ISO100 Sony A6000. Camera is mounted on old Pentacon Macro tripod with WeMacro focus rail set on 1-1-1seconds which is quite enough to get rid of vibration. I GUESS the reason for them to hate flash is extreme output of violet and blue light emmited by xenon tubes, while they can tolerate flooding with green-yellow-red dominant LEDs.
https://www.ncbi.nlm.nih.gov/pubmed/1566330
-We're growing them in Petri dishes, and i've found out it's best for their lifespan to keep them on agarose, or if they need to be removed from the dish, its best to cut them along with some agarose. They can stand hours of photographing this way, but single stack should be kept as short as possible because they still display some kind of phototropism (probabely much less visible on your subjects).
-My subject is something between 1-30 milimeters. Im using 2 lenses: Minolta 100mm F2.8 Macro for 25-30mm objects
and Mp-e65 for anything else
I was using Nikon Plan 10x on 135mm tube lens, but i decided to drop it, because stacks were taking a long time and i decided that it's NOT worth it. You might consider comparing stack with 10x/0,25-0,3 and Mp-E65 or 4x/0.1 and decide if you REALLY need that extra resolution or not? While they look sharper (10x) in my subject case, they werent displaying anything that was crucial to our experiment and stacking with 4-5x is at least 2x as fast as with 10x
Cellular resolution cropped from picture above, which was taken with Mp-E65:
-Another thing is that you might try to shoot through container. I've tried this some time ago (pardon the undiffused ring light) and results were promising, but i didnt yet developed proper techniqhe then, and whole idea was dropped untill we start new research next year.
5x/0.25 with petri dish open
4x/0.1 with petri dish sealed
Rough comparision:
Does 5x look sharper? Yes. Does it have better resolution? Yes, as you can clearly distinguish between blains and stoma. Why 4x is worse? Because it's NA 0.1 vs 0.25 AND it was shoot through 1,5mm of not so transparent plastic. Question is if 4x is good enough for you? If yes, the difference between them was 40steps and 160 steps - quite a substantial one.
TLDR: IMO lower resolution, warm continous light source, and maybe sealed container, might help you with your project.
I didnt read the whole thread as it have 30 pages already, so i apologize if some of those are not helpfull, but here are just a few ideas to consider:
-Im doing kinda similar thing for a living. Part of my job is photographing fern explanatats, and what i've found out is that they just hate flash lamps, while they can stand hours of continous light (despite emmiting quite a lot of heat), so i ended up with using 6 Jansjo lamps diffused through lab paper with shutter times ranging from 1/5 - 1/30 with EFSC on, ISO100 Sony A6000. Camera is mounted on old Pentacon Macro tripod with WeMacro focus rail set on 1-1-1seconds which is quite enough to get rid of vibration. I GUESS the reason for them to hate flash is extreme output of violet and blue light emmited by xenon tubes, while they can tolerate flooding with green-yellow-red dominant LEDs.
https://www.ncbi.nlm.nih.gov/pubmed/1566330
-We're growing them in Petri dishes, and i've found out it's best for their lifespan to keep them on agarose, or if they need to be removed from the dish, its best to cut them along with some agarose. They can stand hours of photographing this way, but single stack should be kept as short as possible because they still display some kind of phototropism (probabely much less visible on your subjects).
-My subject is something between 1-30 milimeters. Im using 2 lenses: Minolta 100mm F2.8 Macro for 25-30mm objects
and Mp-e65 for anything else
I was using Nikon Plan 10x on 135mm tube lens, but i decided to drop it, because stacks were taking a long time and i decided that it's NOT worth it. You might consider comparing stack with 10x/0,25-0,3 and Mp-E65 or 4x/0.1 and decide if you REALLY need that extra resolution or not? While they look sharper (10x) in my subject case, they werent displaying anything that was crucial to our experiment and stacking with 4-5x is at least 2x as fast as with 10x
Cellular resolution cropped from picture above, which was taken with Mp-E65:
-Another thing is that you might try to shoot through container. I've tried this some time ago (pardon the undiffused ring light) and results were promising, but i didnt yet developed proper techniqhe then, and whole idea was dropped untill we start new research next year.
5x/0.25 with petri dish open
4x/0.1 with petri dish sealed
Rough comparision:
Does 5x look sharper? Yes. Does it have better resolution? Yes, as you can clearly distinguish between blains and stoma. Why 4x is worse? Because it's NA 0.1 vs 0.25 AND it was shoot through 1,5mm of not so transparent plastic. Question is if 4x is good enough for you? If yes, the difference between them was 40steps and 160 steps - quite a substantial one.
TLDR: IMO lower resolution, warm continous light source, and maybe sealed container, might help you with your project.
Oh my goodness JohnyM! Thanks for dropping in and for kindly explaining all of that. It sounds as though I need to try some LED ikea light then. Thanks! I'll get right on to that. :-) (Gosh!)
Your photos are really amazing. Would you mind my asking where you work? That's an amazing job you have there.
Your photos are really amazing. Would you mind my asking where you work? That's an amazing job you have there.