IR and Lenses

What I want to know is why flare is so much more pronounced with digital IR than it was with film IR. I have photos I took on IR film with the sun in the photo that have no more flare than regular color photos. Not so with digital IR!

To the blog group,
after reading many of these hotspot reports I see the IR hotspot is still pretty mysterious.

When I bought a Sony DSC-R1 in May 2006 and had it converted at MaxMax, my major concern was whether the fixed Zeiss 24-120mm (equiv) lens had an IR hotspot.

Because this camera has a very useful electronic viewfinder, I was able to devise a simple test for the hotspot. I aimed the camera at illuminated white no-seam and worked through the zoom range. At ~65mm (equiv), the Zeiss Sonnar formed a tight hotspot at f16. Looking at the EVF, I could see the hotspot form and dissolve as I zoomed through that trouble area. Aperture played a big part also; as I opened from f16, the spot became more diffuse until it was barely perceptible at ~f5.6. (Of course, there is no hotspot in normal visible wavelengths.)

So, the IR hotspot is a result of internal IR reflections; it is possible that these reflections can be controlled by the selection of aperture and focal length. Now that I know where the problem is on my lens, I avoid that narrow area. In my thousands of IR exposures, I have never seen the hotspot.

While my simple test will not help anyone who is shopping for a lens, it will help you map out the best areas for the lenses you already have.

Dear Gisle and community,
thank you for such a rich resource. And thanks Stan for sharing your test procedure (Gisle too for the white paper test). I plan on systematically testing all my lenses soon!

With that out of the way I will share some info. To begin I have been doing photography a long time and have been a regular infrared shooter (all year, not just summer!) since the early 90's. A year and a half ago I went digital, and shortly thereafter stumbled onto a Canon 350D converted to infrared. I'm not so crazy about digital but I'm liking digital IR very much. Well, except for hot spots!

So for those of you who by used and older equipment, here are some recommendations for good lenses from Canon.

EF 80-200 2.8 L Superb, superb! Even better than the newer descendants as you only need to refocus at 80mm (from 100mm up it is apochromatic). Big minus is its heavy weight and inability to use Canon teleconverters.

EF 100-300 5.6L Another fantastic lens, but quite a prima dona generally. It's actually better suited for digital IR than film because it does not like any filter that is not clear: you lose autofocus, then the image is so dark you cannot manually focus! I'd recommend this only for converted cameras so you can just use a UV or other protection filter. Again, at the widest setting (100mm) you have to refocus but from 135mm up you can use autofocus.

TS-E 24 Seems good, but I've rarely used it as it has nasty chromatic aberration on color digital. The few images I've taken have been good but they are very few and all in low light. I'll have to do some more shooting.

Added info on two lenses already reviewed:

EF 50 1.4 Yes, sometimes has a hotspot. Worse is its notorious tendency to front focus even in normal shooting, so that even when you refocus to the IR mark the picture may stay sharp. A very frustrating lens to use in IR. However, I've noticed on a very few shots under tungsten lights I have gotten what looks like steam or vapor from people against dark backgrounds. A very cool effect and I don't know what it is (heat and sweat?). It is very rare and unpredictable but fantastic when it happens. It keeps me shooting this lens in IR. Kind of like buying a lottery ticket, I guess!

EF 16-35 2.8 L I bought this lens specifically so I could shot IR and was rewarded with its notorious and nasty hot spot. This on top of a generally propensity to flare. Not recommended, although sometimes you can get a good image, and some of the marginal images can be cleaned up in post processing. Instead, go for the absolutely glorious EF-S 10-22mm, which is my hands-down favorite Canon lens for shooting infrared. Maybe its the Super UD element but it is clearly superior even when looking at thumbnails.

That's it. I hope my info was useful. Happy shooting!

I can add that the Canon 300mm f/4 L IS lens is very good for IR with no hot-spot seen at all on a converted 5D body with the internal filter having the response characteristics similar to the R72 and 89b external filters.

Does anyone have infrared experience using Canon FD lenses? I'm particularly interested in their fast wide-angle lenses.

The Canon EF-S 17-55 f/2.8 does NOT produce a hot spot. I have an IR-converted Canon XTi... and I have yet to see a hot spot at any focal lenth. The lens is excellent, and my IR images are coming out very nice. It's a great combination.

My sigma 10-20 f4-5.6 showed a slight hot spot. Not terrible but not great.

I had good luck with the 50mm Sigma macro using a filter (Cokin 007). The kit lens Canon 18-55mm was unusable as you note above.

BK

i have this lens with my ir converted camera and it works great, with no hotspots.

Also my M42 lenses Soligor 21mm f/3,8 and Carl Zeiss Jena 35mm f/2,4 are working pretty good.

Phostructor said the following:

To All Digital Infrared Photographers:
This is to announce the creation of the
Lenses for Infrared Photography Wiki at http://irhotspots.wikia.com/
Your experience and data are vital to help develop this database of lens performance for IR photography. If you know what a hot spot is, then you are qualified to contribute. There is room for data that has been methodically tested and gathered, and there is also room for less formal data. Please head on over and put in your data, and know you'll be helping many other photographers fascinated with the potential of infrared.

Please pass this on to any person or group interested in IR photography!

or just long ones?

Thanks for the detailed conversation!

@Tali

My experience is that the aperture may have an effect on the hot-spot, but not the shutter speed.

Hot spot is very pronounced when at 18mm f/9-11. What I observed as I took shots of different focal length, hot spot seems to dissolve when zooming in, disappearing at around 24mm with the same said aperture.

Trying to adjust the aperture higher (going to f/16), hot spot also seems to dissolve but this may require you more exposure time.

Though I am not quite sure I am correct, I hope that it may give you some info and try operating at different f lengths and apertures; hot spot will not appear at some f length and aperture values.

I have used canon ef

• 28 1.8
• 300 2.8
• 400 2.8
• 400 5.6
• 600 4
• 1.4x II tc

all with good results and no hotspots with a lifepixel converted camera.

This lens DOES produce a hot spot in IR photos.
 

I have used the Tamron 18-200 extensively for 720nm filtered infrared and have never seen an hotspot on any of my images. I traced the listing of problems to a 2006 report. Perhaps new er versions of the lens do not produce hotspots? Please consider removing this lens from the list

I've been using the Samyang 14mm for some weeks now, and it's spectacular for IR photography (modified Nikon D80, Wratten 87), with no hotspots. Sharpness is superb right out to the corners, right from f2.8.

I've been using the Nikon 18-55 and 16-85mm zooms, which are pretty good, although sharpness becomes worse as CA increases off-axis (no hotspots, though).

who about sigma Sigma 8-16mm F4.5-5.6 DC HSM (Canon Mount) ist hot spot ot not thx

Have had few to no problems with the Nikon 24-120 vr
 

In my experience (mostly with modified 5DII cameras):

The 17-40/f4 L and the 85/1.8, both listed as "may produce a hotspot" are fine.

The 24-105/f4 L, listed as OK, does produce a distinct hotspot at f8.

The 200/f2.0 L, not listed, also produces a distinct hotspot at f8, but not when you shoot it wide open. I don't consider this a problem--what's the use of having such a glorious lens if you don't shoot it wide open? It took me more than a year before I happened to shoot a frame at f11 and first noticed the problem.

I don't see the above-referenced lens, or any Zeiss lenses for that matter, on the lists. Anyone have any experience using this lens for UV/IR?

I have a pair of Tamrons

11 -18 leaves a hot spot

17 - 50 f2.8 leaves a hot spot both while using a 72 IR filter on a Canon 10D

28 - 105 f3.5 - 4.5II canon lens will not leave a hot spot this is the good one they made 3

One more lens is the canon 20 - 35mm f 3.5 - 4.5 it leaves a hotspot

I used this lens with filters and with converted camera and no hot spot.

Tokina 11-16mm f2.8 has nasty hotspot right from the maximum aperture.

Just tried this lens with a hoya R72 filter and it produced a hot bar across the image plane with a slightly larger spot in the center. I do not reccomend using for IR...

hi! which of this lens produce hotspot?

which is a better lens for InfraRed? Tnx

the Canon 18-55mm f/3.5-5.6 EF-S is mentioned in the introduction as producing a (pronounced) hot spot but in the listing this applies to the IS version and not the non-IS (bit confusing)

but I only found the #II version (non-IS) so far (49 eur) is that version also ok for IR? If the Canon 18-55mm f/3.5-5.6 EF-S II also has hot spots I consider to use a 720nm on my 24-70L instead (less wide angel and more expensive filter). Tips are we;come

Nikon 24-70mm: Produces hotspots in most shots, but they are almost invisible. I went out and shot maybe 50 pics yesterday using a Hoya R72 filter, between f/2.8 and f/11, it was a hot and brightly lit day, and only maybe 2 shots have noticeable hot spots. The spots are more noticeable in color than in B&W.

Nikon 18-35mm f/3.5-4.5 AF-D IF-ED: this lens produces a very noticeable hot spot in most of the shots I took with it. Bright circle, quite unlike the barely visible and very fuzzy spot of the 24-70m.

I have this lens and make hotspot, i try other one and its the same. isnt good for IR photo.

If anyone is interested, I have put together a list of all the hotspot reviews I could find and my own results here: kolarivision.com/lenshotspot.html.

500 mm nikon vr, 70-200 f2,8 nikon VR2 and 24-70 f 2,8 sigma don't make hotspot.

The old version - prior 2005 works very well with my D70 and D200 IR converted cameras - no hotspots ever seen. My very old sigma 28-105 was very bad for IR.

Regards Johann van der Walt

No hot spot with these nikon lenses.
 

shot this lens on my Nikon D700, converted to IR Deep Black and hot spots appeared in all images. it was a rental lens and I will not be buying a copy.

took a test shot of a newly purchased Citiwide 720nm IR filter w/ the Nikon 18-35mm , first 2 shots ISO 200, exp. about 20-25 seconds, f/8... a horizontal light streak appeared on the lower part of the image... could be because i didnt engage the eyepiece shutter to prevent light leak from the viewfinder (hopefully) more tests to be done before confirmation of light streak issue.

I have two canon cameras that have been converted to infrared: 720nm and 590nm. The hotspots I've gotten in images are much more pronounced with the 720nm vs the 590nm.

I'm using a Nikon 50mm 1.8D on a D7000 and I've noticed a very distinct hot spot at f8 and smaller. At f1.8 there is no trace of the hot spot. Haven't bothered checking the range between f1.8 and f8. Also the lens Nikon 18-105mm 3.5-5.6 is unusable at all focal lengths and f-stops. Same goes for Nikon 55-300mm 3.5-5.6.

Any one try the Zeiss 21mm distagon on an IR mod body?