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by miker on Thu Oct 05, 2017 4:30 pm
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I'm rather reluctant to modify a camera to shoot IR without doing some testing I think with an IR external filter.  How effective are the external filters?  More than likely it's better to modify the camera but it's about $275.00 and I don't know if the results justify converting a camera.  It seems like an external filter is a cheap way to see if I'm really interested in IR photography.
Michael Rubin
 
 

by E.J. Peiker on Thu Oct 05, 2017 5:25 pm
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There are a number of issues you will need to deal with.  Most cameras will not work the way you expect with an external filter.  This is because the filter over your regular color sensor cuts IR (and UV) so if the sensor will record any IR at all, it will require VERY long exposures.  If it let a significant amount of IR (or UV) through, your colors would be significantly altered in normal photography.  Think in terms of 10 seconds instead of 1/100s for example.  And that's if it works at all.  You will have to research if your particular camera will work with a regular filter, many won't but even if it does it will require very long exposures.  If you have a camera converted, the original sensor filter is replaced with a new one at whatever wavelength of light cut-off that you specify - typically 590nm, 665nm, 720nm, or 830nm - the filters allow a decreasing amount of color to be recorded.  I just put up three new galleries of IR photos that have a mixture of false color IR (shot with 665nm) to monochrome IR (shot with 665nm and 720nm).  If I were to convert another camera I would go with 590 because it allows me to do anything from very colorful IR shots to high contrast B&W just by using different processing techniques.

Here are the galleries - they may help you decide:
http://www.ejphoto.com/illinois_page.htm
http://www.ejphoto.com/forest_park_page.htm
http://www.ejphoto.com/tower_grove_page.htm

Let me know if you have other questions.  you can always send me a PM.

Finally, if you want to do regular color and IR with a single camera, you could convert the camera to full spectrum and then add UV and IR cut filters to the front of your lens when wanting to shoot regular color and add whatever visible light cut you want (the filters I mentioned above) if you want to do IR.  But again, this will significantly lengthen some of your exposures.
 

by SantaFeJoe on Thu Oct 05, 2017 6:18 pm
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IR pass filters are not that inexpensive. If you are interested in trying IR, you can probably find a used Sony camera like the DSC-H50 or an old Nikon D70(not the D70s). Many Sony cameras have a Nightshot mode that removes the IR block filter from the path of the sensor. Then it's just a matter of placing an IR pass filter in front of the lens. The exposures are quick. The same is true of the Nikon D70, 950, Sony 828 and many others. One advantage of using these cameras (don't remember if this is true with the D70) with the filter is that you see the image through the viewfinder as it will appear without having to use Live View. If you like IR after trying it out, then you will certainly want to have a dedicated IR camera. If you try using an IR filter on most DSLRs, you will not see anything through the viewfinder. You must focus first and the place the filter over the lens. The exposures will be way too long for most anything that moves even slightly. Certainly not a practical method.

Joe
Learn the rules like a pro, so you can break them like an artist.  -Pablo Picasso
 

by andre paul on Thu Oct 05, 2017 9:01 pm
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with a hoya r72 my d810 images usually takes from 20 to 30 seconds to make ir images ( low iso , f8 ).
good way to produce long exposure time images ...
converted cam is so practical and fun....normal exposure times....
i use a 590nm converted d7100 from lifepixel ( super color IR ) . same results are not possible with the r72 filter.....

if yu want something different , converted ir cams are very fun !!!!!!!

andre.
andre reichmann
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by andre paul on Thu Oct 05, 2017 9:07 pm
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Image
just an example of super color infrared. Multiple effects can be obtained with  different pos processing techniques as EJ pointed out .... . 
cut off filter - 590nm.
andre reichmann
**sao paulo-brazil**
 

by miker on Thu Oct 05, 2017 9:13 pm
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I've read that newer cameras don't work with external IR filters because they filter nearly all IR out so it doesn't reach the sensor. I have a Nikon v1, an a6000 and an a68. Does anyone know if any of these cameras will work with a Hoya r72 filter
?
Michael Rubin
 
 

by Wildflower-nut on Thu Oct 05, 2017 9:14 pm
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Are you better off with a mirrorless camera for IR photography?
 

by E.J. Peiker on Thu Oct 05, 2017 9:19 pm
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Wildflower-nut wrote:Are you better off with a mirrorless camera for IR photography?
Yes, very much so because you do not have AF calibration to the IR spectrum to deal with since focus is on sensor.  I definitely recommend a mirrorless camera if available,
 

by SantaFeJoe on Thu Oct 05, 2017 10:08 pm
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E.J. Peiker wrote: Finally, if you want to do regular color and IR with a single camera, you could convert the camera to full spectrum and then add UV and IR cut filters to the front of your lens when wanting to shoot regular color and add whatever visible light cut you want (the filters I mentioned above) if you want to do IR.  But again, this will significantly lengthen some of your exposures.
This is not exactly correct. With a full spectrum filter (clear glass) all light waves pass through, therefore the exposure is not nearly as long as when an IR block filter is left in place. It would be comparable to an IR converted camera with the same filter type as attached to the front of the lens of a camera with a full spectrum conversion.

https://www.lifepixel.com/infrared-phot ... -ir-filter

Joe

Edit: I have even hacked camera phones to shoot IR by removing the lens and breaking out the red element at the back of the lens. This is the IR block filter. I then placed a piece of developed, but unexposed, slide film in front of the lens. The exposure times were very short and hand-holdable.
Learn the rules like a pro, so you can break them like an artist.  -Pablo Picasso
 

by SantaFeJoe on Thu Oct 05, 2017 11:03 pm
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I forgot to mention that I'm pretty sure the viewfinder will be useless on a full- spectrum converted DSLR with a front IR filter in place. You will certainly need to use live view to focus and compose or else you can focus/compose without the filter and then attach the filter. With an EVF, you will see what the sensor sees.

Joe
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by E.J. Peiker on Fri Oct 06, 2017 5:44 am
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SantaFeJoe wrote:
E.J. Peiker wrote: Finally, if you want to do regular color and IR with a single camera, you could convert the camera to full spectrum and then add UV and IR cut filters to the front of your lens when wanting to shoot regular color and add whatever visible light cut you want (the filters I mentioned above) if you want to do IR.  But again, this will significantly lengthen some of your exposures.
This is not exactly correct. With a full spectrum filter (clear glass) all light waves pass through, therefore the exposure is not nearly as long as when an IR block filter is left in place. It would be comparable to an IR converted camera with the same filter type as attached to the front of the lens of a camera with a full spectrum conversion.

https://www.lifepixel.com/infrared-phot ... -ir-filter

Joe

Edit: I have even hacked camera phones to shoot IR by removing the lens and breaking out the red element at the back of the lens. This is the IR block filter. I then placed a piece of developed, but unexposed, slide film in front of the lens. The exposure times were very short and hand-holdable.
Most of these filters do have a filter factor of 1/3 to 2/3 of a stop - I probably shouldn't have used the word significantly though so it will be a bit more exposure than the full spectrum without filter but, yes, it should be similar to the exposure on a non converted camera.
 

by Wildflower-nut on Fri Oct 06, 2017 8:36 am
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If you eliminate any filter on the sensor, does this mean you could change the infrared cutoff point by simply changing filters?
 

by SantaFeJoe on Fri Oct 06, 2017 10:02 am
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Wildflower-nut wrote:If you eliminate any filter on the sensor, does this mean you could change the infrared cutoff point by simply changing filters?
Yes, but you still need the full spectrum glass for optical reasons and to protect the sensor.

Joe
Learn the rules like a pro, so you can break them like an artist.  -Pablo Picasso
 

by miker on Fri Oct 06, 2017 2:42 pm
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How feasable is converting an a6000 to two spectrums, vis and IR, concerning IQ on both spectrums. Would I need more filters for each, vis and IR?
Michael Rubin
 
 

by E.J. Peiker on Fri Oct 06, 2017 2:46 pm
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miker wrote:How feasable is converting an a6000 to two spectrums, vis and IR, concerning IQ on both spectrums.  Would I need more filters for each, vis and IR?
That would be the full spectrum conversion we talked about.  You would then need at least two filters for your lens, one that cuts off UV, the other that cuts off visible light at whatever wavelength you want to cut it off at.
 

by ChrisStarbuck on Mon Oct 09, 2017 8:26 pm
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E.J. Peiker wrote:
miker wrote:How feasable is converting an a6000 to two spectrums, vis and IR, concerning IQ on both spectrums.  Would I need more filters for each, vis and IR?
That would be the full spectrum conversion we talked about.  You would then need at least two filters for your lens, one that cuts off UV, the other that cuts off visible light at whatever wavelength you want to cut it off at.
I recently had my old Canon 50D converted to full spectrum by Life Pixel, and bought 3 filters for it:
[ul]
[li]visible pass-band, which blocks both UV & IR in a single filter (just like the camera's original built-in filter), restoring the full-spectrum converted camera to its original visible spectrum operation;[/li]
[li]"super color IR", which has a 590nm cutoff, and thus includes visible orange & red along with IR, and[/li]
[li]"standard IR", which has a 720nm cutoff; this still has a tiny bit of visible red leakage, so you can post-process to get a little color in the image.[/li]
[/ul]

I had 2 reasons for buying the visible pass-band filter: one is so the camera is still usable as a backup for normal color photography, and the other is so I can take visible + IR photos that are framed exactly the same (which then allows overlaying the two).
Chris Starbuck
[url]http://www.chrisstarbuck.com[/url]
 

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