infrared filters

[coigach]

I'm looking for a square filter to fit the Lee filter system that is the equivalent filtration of the Hoya 72 filter (I think the Hoya is the equivalent of a Wratten 89b?) Is the Cokin Z - 007 equivalent to an 89b (or even a Hoya 72 :confused, and does it fit the Lee system?

Help...!

Cheers,
Gavin

 

[Gary Holliday]

Hi Gavin,

I had been searching for a while to get a 100x100mm IR filter. The filter available to us in the UK is the Cokin Z007 which is a 72. Lee only do an 87 as I'm sure you are already aware.

The 100x100mm Cokin Z007 is expensive, so I decided to buy a 67mm Heliopan RG695 which was about the same price from Teamwork. I was able to pick up a Hass. bay60 - 67mm adaptor for nothing on feeBay. I'm sure the Heliopan will last longer than a Cokin resin filter plus I'm getting the Schott glass.

http://www.teamworkphoto.com/index....79_246&zenid=823bccab51ead61b17403f99272992e1

The Kodak Wratten 89B 100mm (4in) resin filter is not available in the UK, so you would need to spend $100 plus postage and customs VAT to get that!

Here is a chart which plots all the IR filters:

http://www.eazypix.de/ir/filter/filter.html

all the best.

 

[coigach]

Thanks for this, very helpful.

Think I'll go down the same route as you and get a Heliopan and stepping ring. Still not cheap though...!

Cheers,
Gavin

 

[Gary Holliday]

One drawback though is that I can't use my lens hood at the end of the 67mm. I've never heard of a 67mm - bay60 adaptor ring.

 

[thebanana]

I wish filter manufacturers would standardize the names and numbers of their products:confused:

 

[Gary Holliday]

I wish filter manufacturers would standardize the names and numbers of their products:confused:

I was trying to think of reasons, from patents to trademarks but it doesn't explain why they are not named after their wavelength. Each company has to have a numbering system which is consistent with the rest of their products.

It appears to be down to my original opinion that it was due to the results of the technicians who produce the filters for each manufacturer...their idea of a wratten 81B is this result. So to avoid confusion they give it a new name.

http://en.wikipedia.org/wiki/Wratten_number

 

[coigach]

Possible daft question - is it possible to use the in-camera metering of a Pentax 67II with the Heliopan RG695 filter or would I have to use a handheld meter?

Cheers,
Gavin

 

[Shmoo]

No...to use your in-camera meter,you'll have to meter at an ISO of 3 or 6 (or whatever your preference is), then put the filter on and shoot. Others read their meters at an ISO of 400 (200, 100, etc.) and open up to compensate. Use a tripod because you'll end up with a longer exposure than can be done handheld usually.

 

[Ole]

Possible daft question - is it possible to use the in-camera metering of a Pentax 67II with the Heliopan RG695 filter or would I have to use a handheld meter?

don't know - but I use the in-camera meter on a Bessa-L (and -T, too) with that filter. Setting the EI to 320 gives good exposure on Rollei IR 400.

 

[colrehogan]

I use a Wratten 89B gel in a Lee gel filter frame.

 

[Gary Holliday]

Possible daft question - is it possible to use the in-camera metering of a Pentax 67II with the Heliopan RG695 filter or would I have to use a handheld meter?

Cheers,
Gavin

I jotted down some notes from this forum when I was researching all the new IR films and possible filters to use.

With Rollei IR 400 and the 092/ RG695/ 89B filters, I have a suggested EI of 12-15. My own method is to enter this ISO into my handheld meter and work from there.

For a dev time I've written Rollei IR 400 - 12 mins 20 degress Rodinal 1+50. I'll be trying this as soon as my filter arrives.

 

[coigach]

More questions...!

Is the filter factor of a Heliopan 695 (wratten 89b equivalent) 5 stops?

Thanks,
Gavin

 

[Shmoo]

It depends. How's that for an answer? Some people like the effect of 5 stops, others 6, some 7. Some shoot ISO 3, others ISO 6, etc. Your best bet is to get a starting point (select your ISO, filter, and starting exposure) and bracket up and down to test out how your camera, film and filter work together.

 

[Gary Holliday]

More questions...!

Is the filter factor of a Heliopan 695 (wratten 89b equivalent) 5 stops?

Thanks,
Gavin

It's about 4 stops but as stated above, increase your exposure. It's expensive film to bracket unfortunately, but IR is unpredictable.

 

[Schafphoto]

Did I miss the part where the type of film was mentioned? Are we talking Rollei, Efke SFX200 or HIE? All are going to expose differently through cutoff filters depending on their sensitivity... The Efke 820IR I'm shooting at ASA1, and developing in TmaxRS at standard Tmax100 time. 072 filter. That gives me an outdoor, bright sun exposure around 2 to 4 seconds at f8 or f11. I never bothered to shoot HIE through a cutoff filter because a 29 plus polarizer gave me all the contrast I wanted. I have samples of the efke at: http://www.flickr.com/photos/schafphoto/

 

[Robert Hall]

Do remember if you are using in camera metering that the metering is not calibrated for how you are shooting, an IR film with an IR filter. The camera meter is setup for more normal full spectrum lights and you are cutting most of that out with your filter, right?

As Schafphoto points out the different IR films will respond widely to how much of the light your camera meter sees is IR as you are blocking most of the visible light from the film as you use the IR filter.

If you use tungsten lights most of what you have is IR light, if you light and meter with florescent it will be very different. So what you will most likely need to do is to calibrate your film, filter, and meter to a given situation - such as full sun - and work from there.