Microfading Tester International Discussion Group

Over the past year I have been creating exhibition lighting guidelines and my research brought me to MFT. I am interested in pursuing construction of a Micro Fade Tester to aid my process.

I am receiving technical support from Martin Fischer, Research Professor in the Department of Chemistry at Duke University, Anna Sheinberg, Chemistry Ph.D. Candidate at Duke University, and Brian Quinby, our Contract Objects Photographer who has experience and personal interest with technical imaging techniques.

After an initial discussion I am reaching out to this group to hear experiences with different light sources (halogen/tungsten vs LED)  to determine what might work best with our varied collection. I am also interested to know the different approaches to testing. And what people wish they knew prior to pursuing their own build. Basically any information that will help guide us at the beginning of this process.

Grateful for any insight provided and happy to answer any follow up questions.

Hello Bryan, welcome! 

Hopefully the resources on this group will be helpful for you. If you are looking for a short, comprehensive introduction to the concept and practice of MFT to get you started, this video is only 3 minutes: https://www.youtube.com/watch?v=5Qc3bSTldOc

There are currently three main MFT designs out there, though a number of institutions have designed and build custom systems. I think, from reading your email, that you're not looking to design something from scratch, though, but more asking about the pros and cons of the Whitmore xenon system vs the Fotonowy vs the retro-reflexive, yes? Each of them has strengths and weaknesses (I've used all three). There will be a bit of a learning curve with any of them.   We have a recoding of a webinar on our channel that introduces and demonstrates these three instrument versions, which you can find here:https://www.youtube.com/playlist?list=PLH0WXCtI2nogmeuWZXn3Qpg_r0huaJc24

Choosing the best fit for your institution will depend on a number of factors, including how and where you plan to use it, how much you have to spend, the types of light in your collection spaces, and how DIY vs. plug and play you need the instrument to be, for your users. (which sounds like...it might be just you?).  You also want to think a little about logistics and about your collections - will the instrument go to the item, or the item to the lab?  Is your stuff mostly flat, or mostly 3D?  Lots of large items? Do you need to be able to mount it on a tripod, a booms arm, or bridge?  Do you make a lot of loans, which might point you to one light source or another? 

Henry raised the topic matching of SPD (spectral power distribution) of the light used in testing as closely as possible to the light in the exhibit/use spaces.  There's a fair bit of literature about the wavelength-dependent fading of materials, both in MFT and in traditional light bank and chamber tests. If you can match perfectly, great.  If you can get close, it's still better than no data, if you remember that MFT gives you "broad brushstrokes" information, and you won't mistake something severely sensitive for something stable or vice-versa even with a mis-match. If you have mixed-source lighting - say, halogen spotlights on the frames and a window or two and whole-room LED's or fluorescents - then you almost certainly want to use a fairly broad emission source (like xenon) that covers all the bases. If your spaces are all 100% LED, get a copy of the SPD for those lamps!  Because white LEDs consist of several individual LEDs, and some have a very intense purple or blue peak while others don't, and that can have a significant impact.  I could go on at length, but I'll just note that it is straightforward to swap in alternative light sources with the Whitmore and retro-reflexive setups, though not at all with Fotonowy.. 

I hope that's at least some help, and feel free to get in touch with further questions. You might want to reach out to an institution near you and ask if you can come observe their MFT in use for a day (check the User Directory in our library), or sign up for one of our MFT workshops that give you hands on time on three different models.  The upcoming one in Scotland is already sold out, but we're planning 2-3 more for 2027. 

all the best,