Infrared, anybody? (Page 10): Here's a little something from just now shot with a nice old 85mm f2 manual-focus Nikkor. It's interesting the difference in IR color handling among...

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Here's a little something from just now shot with a nice old 85mm f2 manual-focus Nikkor. It's interesting the difference in IR color handling among various lenses -- this picture is uncorrected, only auto white balance and red-blue channel swap. Even stopped all the way down I found no hotspot in the lens. I think it renders a kind of southwestern flavor in the colors.

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In case there's interest, my 25mm f1.8 Meike lens arrived a couple of hours ago, and I've been seeing how happy it is with infrared. Answer is that it's just fine up to f8 (and conditionally f11) in black-and-white, and fine up to f5.6 in color, though after that it develops a hotspot. Here are f5.6, f16, and f11 in black-and-white. (Pictures made for testing, not artistic, purposes, and are OOC jpegs with auto white balance and color swap for those in color, and auto white balance alone for the black-and-white.) I'm happy with the lens, which is extremely pleasant to shoot. And yes, I know my sensor is filthy. And I wish Meike made a 16mm lens -- 25 just ain't wide enough on a half frame.

wingclui44 Loc: CT USA

depscribe wrote:

In case there's interest, my 25mm f1.8 Meike lens ... (show quote)

That 'hot spot' was clearly seen.
One question I want to ask, why did you still need to set auto balance when in processing, you had already set the custom WB in camera. Can I go directly to channel swap, and skip the auto WB in PP?

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wingclui44 wrote:

That 'hot spot' was clearly seen.
One question I want to ask, why did you still need to set auto balance when in processing, you had already set the custom WB in camera. Can I go directly to channel swap, and skip the auto WB in PP?

Auto white balance in post pretty much always makes things better, in IR or in conventional photography, for the same reasoning that with film, even perfectly exposed negatives don't always have the same exposure time in printing. You don't have to do it (there are even people who don't channel swap, which renders pictures, often, that look like Martian landscapes), but I think you'll like your pictures more if you do.

wingclui44 Loc: CT USA

depscribe wrote:

Auto white balance in post pretty much always makes things better, in IR or in conventional photography, for the same reasoning that with film, even perfectly exposed negatives don't always have the same exposure time in printing. You don't have to do it (there are even people who don't channel swap, which renders pictures, often, that look like Martian landscapes), but I think you'll like your pictures more if you do.

I will try both to compare them to see what's the difference! Thank you!

JimH123 Loc: Morgan Hill, CA

depscribe wrote:

Auto white balance in post pretty much always makes things better, in IR or in conventional photography, for the same reasoning that with film, even perfectly exposed negatives don't always have the same exposure time in printing. You don't have to do it (there are even people who don't channel swap, which renders pictures, often, that look like Martian landscapes), but I think you'll like your pictures more if you do.

Auto WB with IR defeats what you are trying to do. If using a 720nm filter, you do a custom WB on green grass, and when you take the picture, you want it to use that WB setting.

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JimH123 wrote:

Auto WB with IR defeats what you are trying to do. If using a 720nm filter, you do a custom WB on green grass, and when you take the picture, you want it to use that WB setting.

Wrong. You can go with OOC, of course, but to claim that adding auto white balance in post defeats what I'm trying to do is simply erroneous. Auto white balance in camera would defeat the purpose, but auto white balance in post, if you know what you are doing, enhances the result.

wingclui44 Loc: CT USA

depscribe wrote:

Wrong. You can go with OOC, of course, but to claim that adding auto white balance in post defeats what I'm trying to do is simply erroneous. Auto white balance in camera would defeat the purpose, but auto white balance in post, if you know what you are doing, enhances the result.

Yes, I tried it, and it did enhanced the result. Thank you!

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wingclui44 wrote:

Yes, I tried it, and it did enhanced the result. Thank you!

The change is remarkable, isn't it. I always do AWB first, because if there are color shift or hotspot problems, it shows them before I'm too far into post. And it's actually helpful if you've shot black-and-white IR, too, though I'm not very deep into the mechanics of why that is, except that it enhances contrast.

JimH123 Loc: Morgan Hill, CA

There is a good site that explains how to set up a custom profile using Adobe's DNG Profile Editor. The directions for using the profile in Lightroom are obsolete since they refer to a much older version of Lightroom.

https://robertreiser.photography/proper-infrared-white-balance-in-lightroom/

Where you find it in the current Lightroom Classic CC is above the Temp/Tint adjustment. You will see "Adobe Standard" with up/down arrows. If you click on that, you can find the profile you create in the tutorial.

The reason for using a custom profile is that the Adobe Standard profile does not allow you to set the temperature below 2000 deg K.

Attached is an example that I created using this technique. I did the chan swap after doing the initial adjustments. After the channel swap, I returned to Lightroom and did the final temperature adjust to set the leaf color. This was done using a full spectrum Sony A55 with a Sony 28mm-85mm f3.5-4.5. I think I used a 630nm filter, since 720nm produces white leaves and 590nm has more color left in the leaves. I should get into the habit of recording what filter I used since after the fact, I forget. I have never seen any hint of a hot spot with this lens.

I also hear lots of talk about not using cheap filters. Well, I guess I have broken that rule. I buy only cheap Chinese filters off eBay. I would have gone broke buying complete sets in as many filter sizes as I use. I've never seen any problems.

(Download)

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The justly revered 14mm f2.8 Fujinon arrived a couple of hours ago. It was rainy and gray and not really infrared-friendly. As soon as the sun came out, I popped outside to see if it's as hotspot-free as it is reputed to be; I believe that it is. The idea of having to shoot without a proper wideangle (my beloved 10-24 is hotspot city) would have been impossible to endure. Now I don't have to.

wingclui44 Loc: CT USA

depscribe wrote:

The justly revered 14mm f2.8 Fujinon arrived a couple of hours ago. It was rainy and gray and not really infrared-friendly. As soon as the sun came out, I popped outside to see if it's as hotspot-free as it is reputed to be; I believe that it is. The idea of having to shoot without a proper wideangle (my beloved 10-24 is hotspot city) would have been impossible to endure. Now I don't have to.

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And one more. I'm stuck at home awaiting a delivery, so my opportunities are limited at the moment, but that can be good exercise, no?

BassmanBruce Loc: Middle of the Mitten

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And one more. I'm stuck at home awaiting a delivery, so my opportunities are limited at the moment, but that can be good exercise, no?

This pic is exactly the type I hope to start with.
This thread has worked well for me. I bought the camera for conversion well over a Year ago and this finally got me in gear. Camera is converted and in mail on way back to me.
So Thanks!

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Delivery got canceled, so I got to make a short trip to the sprawling metropolis that is Amesville, Ohio, and made a couple of pictures there.

This field is across from Main Street

And this is Main Street
And this is Main Street...