Beginners Question on Mirror Slap
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Beginners Question on Mirror Slap
Hi:
This is my first posting. I am a retired biology teacher (16 years retired) but active as an outdoor writer and maintaining an interest in photomicrography of protists and other small aquatic invertebrates.
I have had some success with videophotomicrography and photomicrography with a Nikon N65 and appropriate 'scope attachment.
Recently I purchased a digital Nikon (D3000) which mounts and works well with the N65 equuipment except for movement of the whole apparatus, 'scope and all, when the "shutter" releases. It appears as though what I understand is called "mirror slap" is blurring the images. I did not have this trouble with the N65.
I am taking the shots by manually pushing the shutter release, which may be part of the problem. Would an IR remote release help this problem?
Can anyone here suggest combinations of ISO settings, shutter speed, and lens opening for general use when the camera is used on manual mode?
My scope is a Wolfe trinocular.
Any help would be appreciated.
Bob Ballantyne
Pennsylvania
This is my first posting. I am a retired biology teacher (16 years retired) but active as an outdoor writer and maintaining an interest in photomicrography of protists and other small aquatic invertebrates.
I have had some success with videophotomicrography and photomicrography with a Nikon N65 and appropriate 'scope attachment.
Recently I purchased a digital Nikon (D3000) which mounts and works well with the N65 equuipment except for movement of the whole apparatus, 'scope and all, when the "shutter" releases. It appears as though what I understand is called "mirror slap" is blurring the images. I did not have this trouble with the N65.
I am taking the shots by manually pushing the shutter release, which may be part of the problem. Would an IR remote release help this problem?
Can anyone here suggest combinations of ISO settings, shutter speed, and lens opening for general use when the camera is used on manual mode?
My scope is a Wolfe trinocular.
Any help would be appreciated.
Bob Ballantyne
Pennsylvania
Welcome!
Having had a peek at your manual, some of the "modes" I was about to suggest, aren't available on that model.
Some Nikons have a very clattery Live View mode. If your model has a Live view mode, don't use it!
Don't touch the camera! Use the self-timer. 5 seconds should be enough to let wobbles settle. An electric, or remote/radio release, is a godsend though.
The mirror raising is a major source of vibration, and will be most significant in the first 20th ( to a quarter, say) of a second of your exposure.
So either
1) use very short exposures - though I doubt you'll have enough light, for say 250th of a second or shorter.
3) use much longer exposures, such as a second or more, so the mirror-induced fuzz isn't noticed. During that time of course the washing machine, passing traffic and the like may be a problem
2) or use flash. You still are best to avoid that first tenth of a second. You can do that by using Rear Curtain Flash Sync on the camera. That fires the flash just before the shutter closes. If you have low ambient light, so that nothing is recorded during an exposure long enough to let the wobbles settle (say a second), the flash, while everything is still, will be the only light.
Iso choice is of course a compromise. Normally "as low as you can" would be the advice, but if things are dim you may have no choice. Above 800 or so I imagine you'd start to see noise.
Try it and let us know how it goes
Edited typos
Having had a peek at your manual, some of the "modes" I was about to suggest, aren't available on that model.
Some Nikons have a very clattery Live View mode. If your model has a Live view mode, don't use it!
Don't touch the camera! Use the self-timer. 5 seconds should be enough to let wobbles settle. An electric, or remote/radio release, is a godsend though.
The mirror raising is a major source of vibration, and will be most significant in the first 20th ( to a quarter, say) of a second of your exposure.
So either
1) use very short exposures - though I doubt you'll have enough light, for say 250th of a second or shorter.
3) use much longer exposures, such as a second or more, so the mirror-induced fuzz isn't noticed. During that time of course the washing machine, passing traffic and the like may be a problem
2) or use flash. You still are best to avoid that first tenth of a second. You can do that by using Rear Curtain Flash Sync on the camera. That fires the flash just before the shutter closes. If you have low ambient light, so that nothing is recorded during an exposure long enough to let the wobbles settle (say a second), the flash, while everything is still, will be the only light.
Iso choice is of course a compromise. Normally "as low as you can" would be the advice, but if things are dim you may have no choice. Above 800 or so I imagine you'd start to see noise.
Try it and let us know how it goes
Edited typos
Last edited by ChrisR on Sat Mar 13, 2010 11:34 am, edited 1 time in total.
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Bob,
Good to see you here. Macro lore says that this is worst at shutter speeds of around 1/15 second. A tripod helps to overcome the blur, preferably together with a cable or air release (not so easy on the latest cameras) but a mirror lock-up is really the answer. I use the whole lot with my film set-up, when not using flash, which is the most reliable solution.
Harold
Good to see you here. Macro lore says that this is worst at shutter speeds of around 1/15 second. A tripod helps to overcome the blur, preferably together with a cable or air release (not so easy on the latest cameras) but a mirror lock-up is really the answer. I use the whole lot with my film set-up, when not using flash, which is the most reliable solution.
Harold
My images are a medium for sharing some of my experiences: they are not me.
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Bob,
Have a look at :
http://micropix.home.comcast.net/~micro ... index.html
Charles Krebs adresses most if not all of your issues.
Hope this helps,
Lars
Have a look at :
http://micropix.home.comcast.net/~micro ... index.html
Charles Krebs adresses most if not all of your issues.
Hope this helps,
Lars
Gallery : http://picasaweb.google.com/BlueDate
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- rjlittlefield
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Bob, there are also other approaches to flash through a microscope --- more add-on, less integrated.
One trick is to put a piece of ordinary glass between the microscope base and the condenser, angled up at 45 degrees, with the flash shining in horizontally. For continuous viewing, the base lamp shines up through the glass. When the flash goes off, enough of it reflects up through the condenser to make the exposure.
As a variation of this technique, some people set up a "snoot" -- a tube lined with aluminum foil -- to channel light from the camera's built-in flash down to the microscope base so it can get sent back up through the condenser.
I've also seen this approach using a fiber optic bundle instead of the snoot. But most of us have a better supply of aluminum foil than fiber optic bundles.
--Rik
One trick is to put a piece of ordinary glass between the microscope base and the condenser, angled up at 45 degrees, with the flash shining in horizontally. For continuous viewing, the base lamp shines up through the glass. When the flash goes off, enough of it reflects up through the condenser to make the exposure.
As a variation of this technique, some people set up a "snoot" -- a tube lined with aluminum foil -- to channel light from the camera's built-in flash down to the microscope base so it can get sent back up through the condenser.
I've also seen this approach using a fiber optic bundle instead of the snoot. But most of us have a better supply of aluminum foil than fiber optic bundles.
--Rik
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