IR filter for B&W

[ymages]

what (very) good IR filter will you suggest for B&W only (with canon

EOS 20D) ?

 

thank you

[denisgermain]

IR filters don't work with most digital cameras... the 20D is one of them.

[ymages]

ha ! good to know

 

thank you

[ymages]

but here they say it works >> http://www.ephotozine.com/forum/viewanswers.cfm?qid=24456

 

with Hoya R72

[grapegeek]

I don't know about the 20D, but on my Rebel I've tried the Hoya R72 with crummy results. I can't imagine that the 20D is that much better. You will have long shutter speeds with wide open apetures. Give it a shot.. The best results are with a fast lens like the 50mm f1.8...

[keith warren]

I experimented a few months ago with a Digital Rebel and got decent results, but the exposure time was around 15-30 seconds as I recall. I have not tried it with my 20D yet, but I would expect similar results from what I have read. These cameras filter out most of the IR. There are sites out there that describe how to remove this filter so you can use the camera for astrophotography, but I was never keen about modifying my camera.

[ymages]

i want to use my 50m 1.8 ... i think i'll have a try

 

thank you

[keith warren]

OK, curiosity got the best of me. I just setup the tripod and made a test shot this out the back window. Midday sun. F1.8, 30seconds, Canon 50/1.8. Tiffen 87 IR filter.<div></div>

[ymages]

then shall i have a go with Tiffen 87 IR filter ?

 

what do you think ?

[digitmstr]

The issue is the IR filters which is built into the camera. That is why Canon has released a model without it and/or there are modifications available to remove it.

 

You can use it an IR filter in front of your lenses but, the results won't be as good because the camera has filter inside which blocks most of IR.

[ymages]

for the price of an IR filter i shall have a try anyway

 

thank you

[grapegeek]

You really need bright sunshine for best results with the 20D or Rebel. As an example of a camera that does better is the old Minolta Dimage 7, a 5mp camera that has a really weak IR cut filter and I can handhold in bright sunlight with speeds of up to 1/60 at ISO 100. With a 20D, you might have to go down to ISO 400. I never had really, really long exposures with the Rebel, but they were long enough around 1-3 seconds wide open on my 50mm lens.

[jonsjons]

you might want to try an 89b (hoya r72) filter instead of the 87. may save you a couple stops...but then your camera may respond differently to different filters.

[awindsor]

I bought a B+W 092 (equivalent to a Hoya R72). You do need bright light (you don't get good Woods effect in cloudy conditions anyway) and exposures are long. Some lenses exhibit hot spots.

 

As a side note, the sensitivity of the new 20Da to IR is not clear. The increased sensitivity to the Hydrogen-alpha emission wavelength (for nebula photgraphy) probably means an increased sensitivity for near-IR but sensitivity to longer wavelength IR is not clear. True IR photography probably still requires modification of the camera.

[ymages]

I cannot find a B+W 092 for my 50mm 1.8 II ..

[ymages]

this list can be helpfull >>

http://photography-on-the.net/forum/showthread.php?t=18698&highlight=ir+hotspot

[awindsor]

If you are in the US then Adorama has a complete collection of IR filters <A HREF="http://www.adorama.com/Filters_Infra-Red_Filters.html">here</A>. <P>

 

The Hoya R72 is also fine. These a very dark red filters but are not opaque. They pass IR and deep reds.

[ymages]

I am in europa but that's not a problem to buy on line

i had a look on Adorama : 49mm ... 52mm .. missed ! :-) nothing for the 50mm

[grapegeek]

Erick, the 50mm f1.8 takes a 52mm filter. Should be quite easy to find that filter size, even in Europe...

[ymages]

ok ! thats what I wanted to know I need the 52 mmm !

thank you