Tips on how to get clear and consistent readings from refractometer?

[Aquavaj]

It seems more than half the time I struggle with getting a clear reading. Clear meaning the cutoff is razor sharp and I can tell the exact reading. Other times it's just a blur even when the markings are focused and sharp.

Last night when testing, my salinity looked to be 2 or 3 points too high (slightly fuzzy line). Couldn't believe it so I tested with calibration fluid and it was on the dot at 1.026. I retest with tank water and was able to get a sharp reading and it was off at 1.028.

I did the same thing on all tests. Place enough water to cover the blue area and drop the clear cover. I let it drop so any excess and bubbles get splashed out. Perfect coverage of the blue area.

 

[nautical_nathaniel]

I don't think I have ever gotten a non-fuzzy reading with my refractometer.

I suppose strong lighting would help and also the angle you are holding it at in relation to the light source. A single source light source should also theoretically provide better results.

#reefsquad, any other thoughts?

 

[Crabs McJones]

I don't think I have ever gotten a non-fuzzy reading with my refractometer.

I suppose strong lighting would help and also the angle you are holding it at in relation to the light source. A single source light source should also theoretically provide better results.

#reefsquad, any other thoughts?

Agreed, lighting is key, to dim or to bright and it's very difficult to read.

 

[saltyfilmfolks]

Do you have a diopter on the eyepiece? It lets you adjust the focus.

 

[redfishbluefish]

I'd try two things:

1. Lubricate your hinges...check THIS out.

2. Try a different light source. Multi-wavelength light source will produce a fuzzier line, while single wavelength will give you a sharp line.

 

[Geebs19]

Agreed, lighting is key, to dim or to bright and it's very difficult to read.

I have to look at mine directly in the sunlight or put my phone camera light on it to make it crystal clear.

 

[MTBake]

I have the same problem if I don't get the lighting just right.

 

[Bayareareefer18]

I had the same issue. What I found is to always use the same light source. I found that holding it closer up towards the light gives me a much more defined line. The light is a ceiling fan with a daylight led bulb

 

[Biglurr54]

Turn the eye piece like you would binoculars to focus the view. Took me a year to figure that out. Smh. Also experiment with lights.

Also, best tip, start saving for a Milwaukee refractometer and let the machine do all the work.

 

[Aquavaj]

I know about turning the eye piece to focus. You can have the markings in perfect focus but still have a fuzzy cuttoff point.

I do recall doing these test with the majority of light coming from my computer monitor. I will try with different lighting to see which gives me the best readings.