Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: Peter Devos on August 11, 2016, 09:55:48 am

Title: Alternative for TG1 filter
Post by: Peter Devos on August 11, 2016, 09:55:48 am
Hi, as i was having a strange white haze on the IR cut filter of my Imacon 528c digital backs, i simple removed that filter .... resulting in a purple IR haze on the images. So i took a Phase one TG1 filter from my scan back and placed it behind the 180mm of my fuji GX 680. I had to glue the glass filter to the back of that lens as there is no other way to attach it any other way. So, now i need an IR cut filter for my 125mm too.....
Does anyone know of a cheaper alternative to the 350$ Phase one TG1 filter?
Title: Re: Alternative for TG1 filter
Post by: Kumar on August 12, 2016, 04:52:49 am
howardglass.com sells Schott glass cut to whatever size you want. The BG-38 is the same glass as that used in IR filters. I got replacement filters for my Betterlight from them.

Kumar
Title: Re: Alternative for TG1 filter
Post by: Peter Devos on August 12, 2016, 10:03:48 am
Thanks for the info Kumar. I will see if they ship to Europe. For now i found a few IR filters from Leaf ( aptus i think) which are mounted in a metal frame and the can easily be attached to whatever lens i want.... as long as the diameter is less than 36mm :-)
Best regards, Peter.
Title: Re: Alternative for TG1 filter
Post by: Kabraxis on August 17, 2016, 04:55:43 am
Just write an message to:

http://www.ebay.com/itm/60mm-x60-x1mm-Schott-BG-39-same-Hoya-CM-500-IR-Cut-color-correction-filter-back-/191929493197?

He will cut down the filter for you. Just check if your removed filter is around 1 mm thickness.
Title: Re: Alternative for TG1 filter
Post by: Kumar on August 17, 2016, 05:06:11 am
I was told that the Betterlight IR filters were made of BG-38 Schott glass. I do not know if the BG-39 is significantly different. The Betterlight Daylight filter is 2mm thick, and the Tungsten filter is 3mm thick.

Kumar