1. 87C IR pass filter commonly results in 0% trasmittance at 790nm, FHWH 50% 850nm; Kodak-.Wratten 87c is equivalent to Schott RG830, B+W093 and Peca 910. Peca 910 filter has been used to acquire images as a stand-alone filter or coupled with Madatec 1070nm. Peca 910, ⌀62mm, 4mm thickness, 0%790nm, 50% 850nm https://www.ir-uv.com/910.html
2. A. Bonanno, G. Bozzo, F. Stranges, P. Sapia:, La riflettografia infrarossa tra fisica, arte e tecnologia, Giornale di Fisica, FISICA VOL. LVIII, N. 1 Gennaio-Marzo 2017.
3. HgCDTE infrared detectors;Norton;Opto electronics review,2002
4. Madatec 1070, ⌀50mm, 3mm thickness, 1070nm(center wavelength +2/-2nm) Full width at half maximum: 20nm(+5/-5nm); Min. transmission: >75% @ 1070nm, cut-off from 200nm to 1100nm(typical),T<0.01% Min. clear aperture: >85% of diameter.
5. Art in the Making Underdrawings in Renaissance Paintings;Bomford,2002