EiscoPremium Quantitative Spectroscope with 5nm Accuracy | Measures Wave Lengths from 400-700nm | Detailed Examination | Electromagnetic Spectrum Scientific Tool

There's a knack to using these, no doubt about that, but they work really well and allow you to see the different spectral outputs of different types of lighting, LED, fluorescent, incandescent etc., and even TVs/monitors. Sunlight is an ideal reference, and there's no safety issue here observing sunlight. You'll be able to see the difference between morning and evening sunlight too. It's possible, though tricky, to take photos through it using a phone camera, for example, showing the spectra and wavelength scale. I can even tell whether a white LED uses a 450nm or a 470nm blue chip! A 420nm laser was clearly bang on 420nm, so one end of the scale is accurately calibrated at least. Light from 660nm and 635nm LEDs appeared in the right places on the scale at the other end and were clearly distinct. Yeah, you should get one if you're interested in this sort of thing!

I have to wear fairly strong glasses in order to be able to focus on the scale above the spectrum, though I can get a rough idea of wavelength just by the colours. You need a certain amount of background light to see the scale.

It works. Bought for viewing flame test spectra in GCSE chemistry. Simple, lightweight, affordable.

A fun device that works well enough to demonstrate the principles of spectroscopy. What is not to like at this price?

As others have said, there is no focusing lens on the eyepiece so anyone with long sight or aging eyes will find it difficult or impossible to see the scale or the spectrum clearly. Also, as has been mentioned, the slit is rather wide so fine lines are not visible (this could be fixed with a bit of sticky tape, at the expense of making it dimmer).I have returned this, and I'm going back to using my home made spectroscope made out of a cardboard tube and a piece of plastic from some diffraction grating glasses. It doesn't have a scale, but I can estimate wavelengths knowing the wavelengths of standard colours.

Works nicely great for the price

A little tricky to get the hang of but come with handy instruction book . Good for checking lights in sleeping areas or for camera setups.

It's ok but don't expect to see any absorption lines in the spectrum. Also, the viewing aperture has no ability to adjust the focus. But for the price what can one expect? It just shows a beautiful rainbow!