Light box and potential issues.

[Leszek Vogt]

My impression is that these boxes are made out of long light tubes and using them for viewing is one thing and photographing a negative something else....the lighting may not be totally even.

Decent LED video light + opaque surface over it might be a better way to go ?

Any helpful suggestions would be appreciated (hopefully @ reasonable cost).

Les

[Bob Salomon]

Old ones were made with various types of flourescent tubes, older ones with straight tubes and newer ones with U shaped tubes, depending on brand, model and target market these all had various Kelvin temperatures and CRI. Photo market professional units usually had a daylight color temperature and a CRI of at least 90 and really good ones of 95+. Today the vast majority of boxes are LED with the same color requirements. Some flourescent and most LED models have variable output. For photo this may not be a desirable feature for viewing negatives and slides that are properly exposed as photo box outputs are designed to deliver the proper amount of light to view detail in the deepest tone while not blinding the viewer while looking at the lightest tones.
X-ray viewers and boxes designed for art or display usually have the wrong output to properly view these slides or negatives.

But the most important requirements are color temperature, high CRI and evenness of illumination. Proper color temperature and high CRI units are usually very evenly illuminated.

[Thalmees]

Any helpful suggestions would be appreciated (hopefully @ reasonable cost).
Les
Hello Les,
Please review this short thread: http://www.largeformatphotography.info/forum/showthread.php?136792-Recommendation-on-lightbox-for-viewing-transparencies&p=1379660#post1379660
Mine is from B&H, it's really a reliable source.
In home I'm using Porta-Trace 11X18 light panel. Not much difference from my Kaiser fluorescent lamb light box in darkroom.