Infrared exposure metering

PeterA

PeterA

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Peter
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I am looking to use infrared B&W film for the 1st time (Ilford SFX) and was wondering what is best method for metering. My camera is an Olympus OM4ti, and was wondering if the TTL will work with the filter attached?

or should you use a hand held meter and if so how does that measure infra red light?

I also heard that you should focus prior to adding the filter. Is this right?

Thanks
 
most of the answers to these questions depend on the filter you're going to use to be honest. If you've got the Ilford SFX 200 red filter, then it's worth about 4 stops, so you can either meter manually with the lens off and adjust by 4 stops by whatever means you see fit, or set the ISO to 25 instead of 200 and fudge it that way. Depending on the ambient light, 4 stops and a heavy red tinge may well be enough to make focusing difficult, it certainly makes AF lenses struggle (though that's not a problem on the OM4ti, I know)

I'd have a good thorough read of the SFX200 factsheet from Ilford before giving it a try personally...
 
the focusing is different with ir ,,,,didnt put that very well did i ? ir focuses at a different point compared to normal light i believe

not sure how it will work with sfx as its not a real ir film is it ?
 
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I used some Rollei IR not long back, the R72 filter I used with it was very very dark, it took iso 400 down to iso 12.
If SFX 200 is iso 200 and the filter you use attenuates it 4 stops, then its the same iso 12 as Rollei IR + R72, I think.
ISO 12 is tricky to meter TTL, how accurate it is or in fact needs to be is open to debate, I'd use a separate light meter, meter at 200 and factor in a reduction of 4 stops and any reciprocity.
It is very definitely tripod country...:)
 
Basically you need to meter at ISO 200 with the filter off and then add on 4 stops to the reading when using the SFX filter or an R72 filter. To focus you need a lens with an IR mark, its usually a little red mark near the infinity mark. With the filter off (its near impossible to focus with it on), focus normally and then move the focus ring until the red IR mark is over where the normal mark was on the depth of field scale. If you shoot on f11 or so then there's sufficient depth of field for any errors in focus to be avoided. Add the filter back on and then take the picture, its likely to be a fairly slow shutter speed so you'll probably need a tripod.
 
Ilford SFX isn't proper infrared film, it does have extended red sensitivity which give an IR look-ish though. If memory serves me right it was developed (pun intended) for speed cameras.
 
Much as I love film, this is one case where digital is going to win hands down I'm afraid.
 
Ambermile said:
Much as I love film, this is one case where digital is going to win hands down I'm afraid.
Click to expand...


wash you're mouth out...:p

Srsly though, I don't see where IR film gives anything more up to digital than any other type of film.
Besides colour IR not being manufactured any more :shrug:, if you want the end product to be IR film, digital isn't ever gonna make your equipment list, hands up/down or sideways ..:D
 
I can go out *now*, take a pic and be back looking at it before your film camera is focused... and that's a live display led preview too. While I'm not saying you are going to get a better or worse image, what I *am* saying is that the negligible difference is not - in my eyes - worth the outlay, both in time and equipment.
 
Art, its an LCD, same as the one on the back of my D200.

You can go out and take a pic and whatever film is in my camera, you'll still be back home viewing it before I've focussed it..that doesn't explain why digital wins IR hands down..:)
 
Horses for courses, I'm not a Luddite, but I *do* love film. In this case though... it's pointless and outdatedly superceded. BTW I do mean my converted to IR digikal here.
 
Arthur

Surely you can see that that argument is most exactly the same argument used by any non film using dig head :thinking:

Therfore, you know it to be wrong !

What makes it worth it, has nothing to do with time or money or effort etc. The thing that makes it worth it, is the same thing that makes B&W and ID11 worth it to someone like yourself (y)
 
I do think that one thing that a properly IR converted digital camera has going for it, is the ability to use the camera in a normal manner - the metering just works - you don't need to go tripod mounted for everything - and you can actually get shots of foliage that aren't full of motion blur without waiting for the one flat calm day in summer. I'm sorely tempted to source a converted digital body that'll work with my EF lenses, just to take along and shoot with at mid-day in summer when the light's too boring for traditional landscape stuff.
 
I get much better results using my £20 Holga and a roll of £5 ir film and a Hoya r72 filter than I've ever had using a digital with a Hoya r72. Much less hassle too, as I can keep the filter on whilst composing :)

Back to the OP's question, I've shot several rolls of Efke IR 820 and I've stopped 'rating' it to an ISO as it acts differently in different lighting conditions. e.g. it's roughly equivalent to ISO 12 in shade but more like ISO 1.5 in bright sunlight. I've not used SFX and I suspect that it will act more like a 'proper' rated film though. Follow s162216's suggestion and bracket every shot :)
 
See, that's my point Mark - with a converted digital one uses it the same as any other camera - point at the image, take the pic. Hence my "Indoors and looking at it..." comment. And also as you point out, my range of targets is the same as it would be for normal parts of the spectrum - even macro.
 
How easy/expensive is it to get a digi slr converted to do IR? Does it impact on normal operation if you don't want to do IR with it?

I always fancied a go at IR but none of my film cameras are IR compatible anyway.
 
Well I paid £35 for mine, an Oly C-something, it's permanent since it involves removing the filter from the ccd/cmos sensor. A friend of mine converts them for the fun of it...I believe he has a couple now, a Sony and another but they are 5mp so likely to be around the £80 mark. Only difference in use is you see an IR pic in the LCD rather than a colour one!
 
Sounds good. Very tempted to do that to my 350 when I upgrade it. Might get an IR filter and have a go just for the hell of it. Make some use of my tripod :)

Would a 50mm 1.7 be a good lens to use as I'm thinking it would at least get more light even though DOF would be more tricky?
 
£35 is very cheap, I thought the replacement hotfilter costs more than that! Cheapest I've seen from a company is £250.
 
It's a bridge - no need for a replacememnt filter since the sensor is not open to the world every time you change a lens.

P1010013-800.jpg



£35 was for the complete camera, already converted.


P1010014-800.jpg
 
Thanks everybody for your helpful comments

TheBigYin said:
most of the answers to these questions depend on the filter you're going to use to be honest. If you've got the Ilford SFX 200 red filter, then it's worth about 4 stops, so you can either meter manually with the lens off and adjust by 4 stops by whatever means you see fit, or set the ISO to 25 instead of 200 and fudge it that way. Depending on the ambient light, 4 stops and a heavy red tinge may well be enough to make focusing difficult, it certainly makes AF lenses struggle (though that's not a problem on the OM4ti, I know)

I'd have a good thorough read of the SFX200 factsheet from Ilford before giving it a try personally...
Click to expand...

Thanks I have printed the fact sheet and will read in more depth.

joxby said:
I used some Rollei IR not long back, the R72 filter I used with it was very very dark, it took iso 400 down to iso 12.
If SFX 200 is iso 200 and the filter you use attenuates it 4 stops, then its the same iso 12 as Rollei IR + R72, I think.
ISO 12 is tricky to meter TTL, how accurate it is or in fact needs to be is open to debate, I'd use a separate light meter, meter at 200 and factor in a reduction of 4 stops and any reciprocity.
It is very definitely tripod country...:)
Click to expand...

Looks like general consensus dependent on filter is 4 stop meter difference, either TTL or hand held. Tripod it is as well.

Is Rollei better? and what are the proper IR films still out there?

s162216 said:
Basically you need to meter at ISO 200 with the filter off and then add on 4 stops to the reading when using the SFX filter or an R72 filter. To focus you need a lens with an IR mark, its usually a little red mark near the infinity mark. With the filter off (its near impossible to focus with it on), focus normally and then move the focus ring until the red IR mark is over where the normal mark was on the depth of field scale. If you shoot on f11 or so then there's sufficient depth of field for any errors in focus to be avoided. Add the filter back on and then take the picture, its likely to be a fairly slow shutter speed so you'll probably need a tripod.
Click to expand...

Great to know. Will need to check out my Oly lenses for this mark.(y)

What is the best light to shoot, I assume bright sunshine (not that we have seen much here in the UK recently!) or is it just as good in shadows.

This IR is all new to me so sorry for what may seem stupid questions.
 
Rollei 400 IR is true IR film, SFX 200 offers extended red sensitivity but its not out and out IR, it produces an IR effect with a 25a filter.
The Rollei produces a strong IR effect with an R72 filter provided there is plenty of reflected IR in the scene.
Which is best ? well Kodak HIE IR, but they don't make it any more, if you want IR film, it isn't SFX, but SFX can be nice enough..:)
Rollei 400 IR & EFKE Aura are true b/w IR films, there may be a few more Adox/Maco with different speeds and IR sensitivity, I dunno I've lost track of who makes what for who and what they call it.

http://www.talkphotography.co.uk/forums/showpost.php?p=1490163&postcount=691

Mohains infinately better Holga Rollei IR shots

You can still get Kodak HIE IR, some bloke is cutting 120 rolls out of sheets of aviation film..
 
srichards said:
How easy/expensive is it to get a digi slr converted to do IR? Does it impact on normal operation if you don't want to do IR with it?

I always fancied a go at IR but none of my film cameras are IR compatible anyway.
Click to expand...

Get a nikon d70 slap on an ir filter job done, no conversion needed.
 
joxby said:
You can still get Kodak HIE IR, some bloke is cutting 120 rolls out of sheets of aviation film..
Click to expand...

You mean the colour EIR varient, unfortunately that guys had to stop cutting it down as Kodak has discontinued the aero IR film. The U.S Forestry Service went back on a deal they made a while ago with Kodak to make the film for at least the next 10 years but as they put it 'due to advances in digital imaging', they stopped the deal and Kodak stopped making it as there was not enough demand sadly.

HIE turns up on ebay from time to time but even if its been frozen its a bit suspect as eventually the background IR radiation affects it.

Anyone interested in IR film photography might like to read this post I wrote a few months ago, it covers the types of film available, filters, metering, focusing, where to get developed, precautions etc.

http://www.talkphotography.co.uk/forums/showpost.php?p=2954752&postcount=3

It is fairly long but quite detailed and hope it helps. (y)
 
joxby said:
Rollei 400 IR is true IR film, SFX 200 offers extended red sensitivity but its not out and out IR, it produces an IR effect with a 25a filter.
The Rollei produces a strong IR effect with an R72 filter provided there is plenty of reflected IR in the scene.
Which is best ? well Kodak HIE IR, but they don't make it any more, if you want IR film, it isn't SFX, but SFX can be nice enough..:)
Rollei 400 IR & EFKE Aura are true b/w IR films, there may be a few more Adox/Maco with different speeds and IR sensitivity, I dunno I've lost track of who makes what for who and what they call it.

http://www.talkphotography.co.uk/forums/showpost.php?p=1490163&postcount=691

Mohains infinately better Holga Rollei IR shots

You can still get Kodak HIE IR, some bloke is cutting 120 rolls out of sheets of aviation film..
Click to expand...

Thanks. The results of Mohains are stunning. Inspiration indeed

s162216 said:
You mean the colour EIR varient, unfortunately that guys had to stop cutting it down as Kodak has discontinued the aero IR film. The U.S Forestry Service went back on a deal they made a while ago with Kodak to make the film for at least the next 10 years but as they put it 'due to advances in digital imaging', they stopped the deal and Kodak stopped making it as there was not enough demand sadly.

HIE turns up on ebay from time to time but even if its been frozen its a bit suspect as eventually the background IR radiation affects it.

Anyone interested in IR film photography might like to read this post I wrote a few months ago, it covers the types of film available, filters, metering, focusing, where to get developed, precautions etc.

http://www.talkphotography.co.uk/forums/showpost.php?p=2954752&postcount=3

It is fairly long but quite detailed and hope it helps. (y)
Click to expand...

Cracking post. Just what I was looking for. (y)
 
swanseamale47 said:
Get a nikon d70 slap on an ir filter job done, no conversion needed.
Click to expand...

... apart from the conversion to superman needed to carry the tripod everywhere, and the conversion to religion also... you gotta be a Saint to have the patience to watch a shutter for 30 seconds ... :D
 
That's where those remote release timers are so handy. You just dial in the time and let them do the counting :) Tripods are awkward. Surprised no one has made a wheely golf style bag for one yet though!
 
I read with interest an article stating that for the Rollei IR 400 film that I am now thinking of getting that it should be used with an ISO of 25 when shooting IR.

So if I then place a 720nm filter in front does this mean I should be metering with - 4 stops because of the filter or just meter at ISO 25?

Also if the weather is dull what time compensation should I take into consideration? 5 elephants (secs)?
 
PeterA said:
I read with interest an article stating that for the Rollei IR 400 film that I am now thinking of getting that it should be used with an ISO of 25 when shooting IR.

So if I then place a 720nm filter in front does this mean I should be metering with - 4 stops because of the filter or just meter at ISO 25?

Set camera to manual, ISO set to 25, compose shot tripod mounted, without filter and meter / set (or remember if very slow time) aperture/exposure time, fit the filter, hope you haven't moved the camera, cover the eyepiece, lock mirror up (if you can on olympus-never used one myself), expose film for requisite time and hope for the best

Also if the weather is dull what time compensation should I take into consideration? 5 elephants (secs)?
Click to expand...
 
Many thanks Mark.

My Olympus OM4ti does not have mirror lock up but have a very sturdy tripod, cable realease & timer to minimise camera shake.

Will purchase some Rollei & give this a go.

No need to compensate for dull conditions then as you meter at ISO25 before placing the filter?
 
the dull conditions thing can be misleading - think of it this way - there are times in summer when it's not particularly sunny - overcast, with only a vague shadow being cast, but you can still feel the sun's warmth striking through the cloud - alternatively in winter it can be sunny and bright, but there's no warmth in the light. IR Photography's a bit like that, you can't always tell what you've got - if you're worried bracket the shots +1/2 and +1ev, otherwise just go with the reading, and hope the film's latitude will soak it up for you. It's really down to getting a feel for the film to be honest.
 
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