Fixed lens for I.R. photography

[Paolo Duzioni]

I'm looking for a fixed lens (range 20-35mm) to use toghether with an hoya ir-pass filter to play a little with IR photography. My camera is a CANON eos 350d (rebel xt in USA i presume)
As i'm told some lenses will produce an hot spot, spoiling my efforts, i'm looking for a fixed lens which doesn't

Maybe canon 28mm 2.8?

 

[Iron Flatline]

That is probably a good lens.

I'm not sure I understand what you mean by Hot Spot. I don't do a lot of IR work, but how would such a Hot Spot show up? Do you mean Lens Flare?

 

[doenoe]

The hotspot is a spot in the middle of the picture. The higher the F-stop, the smaller the spot.....but it will be more obvious then using a lower f-number....had that when i shot with the kitlens of the Canon 350D.
I now use the Canon 50mm 1.8 MKII. Works like a charm, no hotspot whatsoever. Cant help you with a lens with the range of 20-35mm though, sorry.

 

[Digital Matt]

I compiled a list a few years ago of lenses which were ok, and lenses which suffered from the hot spot issue. (due to lens coatings)

I don't know how up to date this is, but it is accurate as far as I know.

No Hot Spot Problem.
Tamron 17-35 f/2.8-4 Di LD (minor, only when using filters that block 100% of visible light)
Tamron 28-75/2.8
EF 17-40mm f4L
EF 24-70mm f/2.8L
EF 28-135mm/3.5-5.6 IS
EF 28mm f/2.8
EF 50mm f/1.8 Mk I & II
EF 70-200mm f/4L
EF 75-300mm f/4.0-5.6 IS
EF 135mm f/2L
EF 100-400mm f/4.0-5.6 IS L
EF 100mm f/2.8 macro

With HOT SPOT
EFS 18-55mm f/4 - 5.6
EF 16-35mm f2.8L
EF 20mm f/2.8L
EF 35mm f/2
EF 24-85mm f3.5-4.5
EF 28-70mm f/2.8L
EF 28-105mm/f3.5 - 4.5
EF 35-80mm f4.0-5.6
EF 50mm f/1.4
EF 50mm f/2.5 macro
EF 70-200mm f/2.8 IS
EF 85mm f/1.8
Tamron 70-300mm f3.x-xxx Macro
Sigma 20mm f/1.8
Sigma 50-500mm "Bigma"
Tamron 19-35mm

 

[Josh66]

That is probably a good lens.

I'm not sure I understand what you mean by Hot Spot. I don't do a lot of IR work, but how would such a Hot Spot show up? Do you mean Lens Flare?

The hot spots he's talking about only happen in IR. It looks like a blown out circle in the center of the image. I think it's caused by the differences in the way visible light and IR light focus, some lenses work fine for visible light but suck at IR.

The kit lens will produce one. I don't have any lenses (other than the kit lens) in the range you're looking for, but the 50mm 1.4 seems to work pretty good. That's the closest I have to what you're looking for.

 

[Paolo Duzioni]

thanks all, expecially 'the man with a list' alias Matt

I'll go fot the canon 28 f2.8