Pages: [1]   Go Down

Author Topic: Canon lenses and Infrared  (Read 12728 times)

Jonathan Cross

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 260
Canon lenses and Infrared
« on: May 06, 2009, 12:35:04 pm »

Getting info from Canon Europe is not something I find easy.  Do Canon L lenses tramsmit infrared?  I have a body that I have replaced and am wondering about getting the sensor modified to respond to infrared, but that is a waste of money if the lenses won't let these wavelengths through.  I met someone last year who had done it and I think his kit is Nikon.

Thanks - Jonathan Cross
Logged
Jonathan in UK

Luis Argerich

  • Full Member
  • ***
  • Offline Offline
  • Posts: 155
  • Astrolandscaper
    • http://www.luisargerich.com/
Canon lenses and Infrared
« Reply #1 on: May 06, 2009, 12:49:42 pm »

All the lenses will let IR thru, the problem is that some lenses produce a nasty effect known as a "hotspot" this is due to reflections of IR in the internal elements leading to a overexposed spot at the center of the frame. While this can be corrected in PP it is to me extremely annoying to the point of not using those lenses for IR photography.

This site has a list of lenses suitable or not for IR photography:
http://www.lensplay.com/lenses/lens_infra_red_IR.html

I found primes like the 50 1.8 and 28 2.8 very good for IR, maybe because of the very simple internal design there are less reflections and refractions affecting IR wavelengths so artifacts and focusing problems are greatly reduced.

Luigi

Tony Ventouris Photography

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 53
    • http://TonyVentourisPhotography.com
Canon lenses and Infrared
« Reply #2 on: May 06, 2009, 12:50:50 pm »

Most lenses work...however there is a chart online somewhere outlining which lenses do not.  Its not that that don't actually work...its that some lenses create a "hotspot" in the frame.  Like a big overexposed middle section kind of.  

I have a 350D Canon converted by Lifepixel to an IR only camera.  (I really want to send a 5D for that too!)

So far I have used the following lenses with great results:

50 1.8 and 1.4
35L
24-105L
100 Macro
Sigma 15mm fisheye

I want to say the 70-200L f/4 IS works too...I just can't remember if ive made any images with it...

EDIT:  Oh wow, that post was made while I was typing!  Excuse the repeated info!  I checked that list and it has the 50 1.4 as not working...hmm...I will have to double check that one...  Interesting that the Canon fisheye doesn't work.  The Sigma does.  Sigma is built nicer too!
« Last Edit: May 06, 2009, 12:53:14 pm by Ancient City Photo »
Logged

johnchoy

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 78
    • http://www.johnchoy.com
Canon lenses and Infrared
« Reply #3 on: May 13, 2009, 09:48:16 am »

My findings is that hotpots depends on the lenses focal length and aperture. the attached shot was test on canon 90mm t/s with my life-pixel converted 5D. The reason why i did this test is beacuse i want to find at which aperture setting will the hotspot grew obvious. As from my experience, longer lenses are prone to this behaviour as the 50f/ 1.8 have miminal hotspot at all aperture setting. My zeiss ze 85 1.4 even suffer hotspot at a larger aperture setting than the 90 TS. since I do a lot of stiching, this is really a very annoying issue.

[attachment=13638:ir.jpg]

Geoff Wittig

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1023
Canon lenses and Infrared
« Reply #4 on: May 13, 2009, 09:27:58 pm »

Quote from: Jonathan Cross
Getting info from Canon Europe is not something I find easy.  Do Canon L lenses tramsmit infrared?  I have a body that I have replaced and am wondering about getting the sensor modified to respond to infrared, but that is a waste of money if the lenses won't let these wavelengths through.  I met someone last year who had done it and I think his kit is Nikon.

Thanks - Jonathan Cross

Canon's L-lenses are a mixed bag regarding infrared transmission. As others have noted, the problem lenses generate a very obvious hot spot near the center of the frame due to internal IR reflections. This can be corrected to some extent in Photoshop, but it kills the image contrast that is one of the most appealing things about IR.

My personal experience with an IR converted Eos-1Ds:
The 24-70 f:2.8 is wonderful, no problem at all. If anything in infrared its sharpness is greatly enhanced compared to visible light. I just printed an image at 24x36" from a single frame capture, and the detail in vegetation is astonishing.
The 24-105 f:4 is almost as good.
The 70-200 f:2.8 is unfortunately almost useless; there's a very obvious hot spot near the center of the frame in any sunlit scene, which includes 99% of appealing IR subjects.
The 100-400 zoom is not bad; no hot spot, and the apparent increase in sharpness overcomes much of this lens's corner softness.
The original 16-35 f:2.8 zoom can work, but there'll be an annoying small flare or hot spot if the sun is just outside the frame. It's worth trying to hide the sun behind something to avoid this. (I haven't tried the 16-35 f:2.8 II yet; I'm waiting for a sunny day and a bit of spare time.)
Logged

johnchoy

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 78
    • http://www.johnchoy.com
Canon lenses and Infrared
« Reply #5 on: May 15, 2009, 11:33:13 am »

Sadly, almost all of my canon lenses do not fit the task of "no hotspot" IR photography.

My 24 -105 f/4 ( tested at 24, 50,70 and 105 range) was not as Geoff said. It's unacceptable to me.

My 70-200 f/4 IS is also usless.

35 f/1.4 fails too.

However, I found the Contax zeiss 135 f2.8 was quite good at avoiding hotspot  even when shooting at f/16.

Just wonder if the older lenses will perform better than the newer one when shooting IR.

cmox

  • Newbie
  • *
  • Offline Offline
  • Posts: 26
Canon lenses and Infrared
« Reply #6 on: May 15, 2009, 04:11:23 pm »

What types of IR filters do you recommend? I have a 5D Mark2 and heard that it needs stronger than average IR filters. Does an IR filter need coating at all? Or could I just one of those el-cheapo filters on ebay?
Logged

Geoff Wittig

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1023
Canon lenses and Infrared
« Reply #7 on: May 15, 2009, 05:28:34 pm »

Quote from: johnchoy
Sadly, almost all of my canon lenses do not fit the task of "no hotspot" IR photography.

My 24 -105 f/4 ( tested at 24, 50,70 and 105 range) was not as Geoff said. It's unacceptable to me.

My 70-200 f/4 IS is also usless.

35 f/1.4 fails too.

However, I found the Contax zeiss 135 f2.8 was quite good at avoiding hotspot  even when shooting at f/16.

Just wonder if the older lenses will perform better than the newer one when shooting IR.

Hmmm.
I've gotten pretty good results with the 24-105, but I'd have to confess that here in the soggy northeast we don't see as much sun as you might get elsewhere. I do tend to default to the 24-70 f:2.8L, mostly because it has a much deeper and more effective lens hood which really helps the hot spot issue.
Logged

Geoff Wittig

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1023
Canon lenses and Infrared
« Reply #8 on: May 15, 2009, 05:36:20 pm »

Quote from: cmox
What types of IR filters do you recommend? I have a 5D Mark2 and heard that it needs stronger than average IR filters. Does an IR filter need coating at all? Or could I just one of those el-cheapo filters on ebay?


Don't bother.
If I understand what you're asking, an external IR filter on the lens to shoot infrared images won't work very well.
Virtually D-SLR's have a very strong IR blocking filter as part of their sensor unit. Consequently if you use a screw-on visually opaque IR filter (i.e., a filter that permits IR wavelengths to pass but not visual), you get absurdly long shutter speeds even in bright sunlight, together with really poor image quality.

You're better off either
1) using one of the compact/point & shoot digicams that are good for infrared (Fuji makes one), or
2) investing in coversion of an older D-SLR to infrared only. This is the highest quality choice, and the results can be really great, but it does involve commiting that camera permanently to IR use. I found this a great solution to an older SLR that was no longer competitive in terms of image quality and therefore just gathering dust at home.
Logged

Robert DeCandido PhD

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 259
    • http://www.BirdingBob.com
Re: Canon lenses and Infrared
« Reply #9 on: February 14, 2011, 06:58:03 am »

Here is a fine list of Canon lenses suitable for IR:

http://www.fredmiranda.com/forum/topic/943179/0#8913758

Regarding the 24-105 F4 - I am just beginning to use it in NYC during winter 2011 with a converted (830nm or "deep" IR conversion) on a 5D2. More to report in the coming days. Attached is an IR image taken with the 5D2 and 24-105 F4 (conversion done by Maxmax to 830nm - no external filter used over lens).

The Contax-Yashica (ZEISS) 35-70 F3.4 zoom is wonderful in B/W infrared on a converted 5D2 (830nm) at apertues at least to F11 and all focal lengths.

Some IR examples with various Nikon/canon cameras converted to full-time IR use:

http://photo.net/photodb/folder?folder_id=637107

The folks over at Nikongear.com have a wonderful IR/UV section:

http://nikongear.com/smf/index.php?board=57.0

Robert DeCandido
NYC
« Last Edit: February 14, 2011, 07:22:09 am by Robert DeCandido PhD »
Logged

sposch

  • Newbie
  • *
  • Offline Offline
  • Posts: 47
Re: Canon lenses and Infrared
« Reply #10 on: February 14, 2011, 05:21:14 pm »

I have a 10D I converted for IR and I too find the hot spot gets worse as the lens is stopped down more. Backlighting really makes it show up more than front lit subjects. Also wide angles seem more susceptible.

With my Canon lenses I find:

16-35mm: at 16mm frontlit good to f13 backlit ok to about f8. At 35mm it can handle f22 frontlit and around f16 backlit.

24-105: about the same as 16-35 over zoom range. I've found hotspots with this lens shooting with my regular 5D body with strong backlight and dark area in the center of the frame so I'm suprised it works at all for IR.

100mm macro: Haven't used it much but seems good to f22 for close ups.

70-200:Not good stopped down. Seems to work best at long end and better with teleconverters attached.

400 DO:Haven't used much for IR. OK at wide aperatures for the 8-10 shots I've taken with it.

My best results have been with my Nikon 14-24mm f2.8G, I use it mainly around f11 and haven't seen any real hot spot issues at all.

Steve.
« Last Edit: February 14, 2011, 11:00:50 pm by sposch »
Logged
Pages: [1]   Go Up