Infrared on the D500

[ArthurDent]

This is my first attempt at infrared.  I thought it was pretty decent for a first attempt, but now that I have a better idea of the exposure parameters, I think I can do better.
D500, 18-55mm f/3.5-5.6 VR2 at f/4.8, 1/8 sec., ISO 6400, Hoya R72 filter.

[ArthurDent]

For comparison, in the visible spectrum (not a direct comparison, different shooting parameters):

[ArthurDent]

A better crop of the IR image:

[bobfriedman]

is this an internal conversion?.. and if so, what is long pass value?

[ArthurDent]

Stock D500, stock cheapo lens and a Hoya R72 filter. Processed as a B&W in Lightroom 6. No conversion work whatsoever.

[Seapy]

Is the D500 not fitted with a low pass filter, or some means if removing the IR and UV from a 'normal' image?

My understanding is that a 'normal' image will be unsharp if contaminated by IR and UV because of the focus shift arising from the extreme spectrum.

Minor edit for clarity.

[bobfriedman]

yes.. so there is a UV/IR cutoff filter... but it may have some leakage.. looks like that is the case here.  i am surprised that the exposure wasn't longer even at that high ISO

[ArthurDent]

Is the D500 not fitted with a low pass filter, or some means if removing the IR and UV from a 'normal' image?

My understanding is that a 'normal' image will be blurry if contaminated by IR and UV because of the focus shift arising from the extreme spectrum.

Have you heard the phrase,”better to be lucky than good?”  It would seem to apply to this photographer. I got the new tripod, drove around until I found a likely location, put the camera on the tripod, took a shot for reference, put on the Hoya R72 filter and the result is what you see. I have no idea as to the construction of the sensor or as to its filtering. I will tell you that I screwed up taking the images. I was using the bulb setting and I thought it worked by depressing the shutter button once to turn it on and once to turn it off. Turns out that is wrong. It stays open only so long as the shutter button is depressed. So I was getting 1/8 second exposures when I was looking for 1 minute exposures. As I said, “better to be lucky. . .”

[Bent Hjarbo]

The T-mode will do the trick, the display shows - - in T-mode.

[ArthurDent]

What is t mode?

[Seapy]

Have you heard the phrase,”better to be lucky than good?”  It would seem to apply to this photographer. I got the new tripod, drove around until I found a likely location, put the camera on the tripod, took a shot for reference, put on the Hoya R72 filter and the result is what you see. I have no idea as to the construction of the sensor or as to its filtering. I will tell you that I screwed up taking the images. I was using the bulb setting and I thought it worked by depressing the shutter button once to turn it on and once to turn it off. Turns out that is wrong. It stays open only so long as the shutter button is depressed. So I was getting 1/8 second exposures when I was looking for 1 minute exposures. As I said, “better to be lucky. . .”

ROFLMAO!

Chuckle... Oh yes, I heard that one, also around here they say third time lucky, nice pix, even if you did get the exposure wrong right by accident!

As Bob says your low pass filter must have some leakage, Birna may have some experience here...  Some of the early DSLR's like the D40 had a lot of leakage and were favourites for IR/UV un-modified.

[Seapy]

...

Reposted in the IR thread.

[Birna Rørslett]

I think this image is largely deep red, not IR as such. The R72 has its 50% cut-off at 720 nm, meaning a ot of deep red and borderline IR will pass it.

Try the 830-840 class filters (for example, B+W O-93) next time and the likelihood of getting an image without extraordinarily long exposures would be slim indeed (I tried myself and got absolutely nothing at f/3.5, 30 sec, ISO 16000).

[Olivier]

True IR or not, I bears a lot of resemblance and this is a lovely image!

[Birna Rørslett]

Yes, any successful image should function on its own no matter what technique has been used ...