I’d like to get started in UV/ IR

[ArthurDent]

My reading indicates the 50mm f/1.8 AIS lens will work well for both ir and uv. Any thoughts?

[ArthurDent]

I probably should have posted this here first, but I've got another thread running in the Flora, fauna section. Anyway, here is my first attempt at IR using the D500. D500, 18-55mm f/3.5-5.6 VR2 at f/4.8, 1/8 sec., ISO 6400. Tell me what you think.

[Seapy]

It would have been good if you had caught the sky like the reference shot, with blue (black) sky behind the spire.  The lack of contrast between the spire and the clouds misses an opportunity to make the spire stand out spectacularly.

Maybe another day?

[ArthurDent]

Tomorrow morning. We are into the monsoon season and it rains nearly every afternoon (it's thundering as I type this but the rain hasn't hit yet). So there are a few good hours early in the day and then the photo equipment must be put away unless one is willing to test his or her efficacy as a lightning rod.

[Seapy]

Looking at this image more closely and having read Akira's post:

I was surprised to see such newer models seemed to have usable sensitivity to IR without modification.  But another article linked in the one you shared (titled "D610 VS. D7100 VS. D7000 Infrared Comparisons") says that they have the IR sensitivity only on the red channel.  That means that, as stated in the article, you only have a 1/4 of the resolution, and the diagonal lines would look jaggy due to the fact that the Bayer demosaicing algorithm is confused.

The older cameras I mentioned (D70, D2H or D40) are sensitive to IR in all R, G and B channels without modification.  So, the demosaicing algorithm works properly, and using very dense IR filters like IR84 or even IR90, you can have beautiful monochrome IR image of good quality.

I think you may be running up against the resolution issue Akira mentions,  that said, I don't dislike the effect and there may be some way of mitigating it, or managing it to your advantage, like grain? Perhaps some way of softening the slightly harsh grain...

[ArthurDent]

Part of the problem may be the high ISO. Here is an image at ISO 200, 30 seconds exposure. The detail  in the trees seems to be much better, but the IR appearance is weaker. Also, much of the detail in the clouds is lost.

[ArthurDent]

I'm hoping there is a happy medium for the strong Florida sunlight, maybe 2-4 seconds exposure, ISO 800+/-, f/6.3-8  might work better. If it is sunny tomorrow morning, I'll go try it again, although not at the church as they will be having services starting early.

[Seapy]

Try several bracketed exposures and maybe HDR some or a couple of them?  There are techniques to layer and multiply to increase range but that's beyond my experience. 

The clouds will loose their detail since they can move quite a long way in 30 seconds, even on a calm day.

[ArthurDent]

I created two copies, dropped the exposure on one by 1 stop and upped the exposure by 1 stop on the other. Then I created an HDR using Photomatix Pro using the two copies and the original. The result is below. I think the detail in the capture is far superior, still need to work on the "IR appearance."

[Akira]

Arthur, have you checked out the RGB histogram?  You can make sure of the amount of datum in each channel there.

[ArthurDent]

Same HDR procedure, except this is the ISO 6400 image. It has lots more noise and doesn't look nearly as good as the ISO 200 image

[ArthurDent]

Arthur, have you checked out the RGB histogram?  You can make sure of the amount of datum in each channel there.

Akira- There is some green and yellow on the left side of the histogram as well as a small amount of blue-green and dark blue on the left side. The right side is all red. Here is the original photo, or almost the original photo, it may have some edits still (primarily to blacks and whites), but the exposure is as it came from the camera.

[Akira]

Akira- There is some green and yellow on the left side of the histogram as well as a small amount of blue-green and dark blue on the left side. The right side is all red. Here is the original photo, or almost the original photo, it may have some edits still (primarily to blacks and whites), but the exposure is as it came from the camera.

Thank you, Arthur.  The unprocessed image looks predominantly red.  The unprocessed images shot with the IR72 filter and the older DSLRs mentioned so far looked more orange.  The difference shows that the orange images has more info in the blue and green channels to tweak for the false color IR images.

[Seapy]

Channel swapping in Ps?

Take it you are making NEF's... Not JPEGS.

Ps CC now has a dedicated IR setting in channel swapping, I have tried tweaking that with reasonable results.

[Birna Rørslett]

As a late answer to a question posted by Øivind many posts earlier (I did overlook this thread, sorry): the IR-converted Nikon D5300 does pretty well. It has the undeniably useful feature of a working Live View and due to the often large focus offsets introduced by IR, one should use LV in practice if focusing is critical. The optical finder isn't among Nikon's greatest performing designs either. For me, the main attractions are the GPS support (a GPS is built in, but unless you kick-start by uploading an aGPS key file, it's way too slow to get a sufficient satellite fix) and the luxury of 24 MPix. My IR-modified D40X delivers significantly better IR quality (thanks to its CCD sensor?), however there is neither LV nor GPS support, and the camera is "merely" 10 MPix.