Is Making Correction on OMR Sheets Possible?
The answer is Yes! You can only if you know how the OMR sheets checking process actually works.
We will discuss three ways of making corrections in the OMR sheet.
Before we discuss them, let’s understand how OMR sheet scanning and marking actually works.
OMR sheets are commonly used today for MCQ-type exams. The agency that takes the exam simply check those OMR answer sheets with the help of an OMR (Optical Mark Recognition) scanner.
OMR sheet checking with the help of a scanner saves time and human efforts in checking answer sheets. Moreover, this technique also minimizes the possibility of error in marking the papers.
While filling bubbles in OMR sheets, certain instructions are given to the candidates.
A candidate must fill the bubbles properly. He must avoid filling or leaving ink marks in two or more bubbles in a single question, etc.
It often happens with candidates that they fill the wrong bubble by mistake. Or, might be that they leave ink marks in other bubbles that might cause trouble for them.
To understand why we must avoid leaving or spilling ink in other circles, we must understand how the OMR scanner works.
How OMR Scanner Works
OMR scanners mark answers with the help of the answer key fed to them. Their scanning works with the help of light reflection.
The machine actually knows the locations of the right bubbles on the OMR sheet. It just scans those bubbles with the help of light reflection to find ink in them.
How do the scanners work with light reflection?
The filled bubbles reflect less light back to the sensor compared to the blank bubble. Hence, less light reflected from the right circle will be marked as correct by the scanner.
The problem occurs when by mistake a candidate fills two bubbles or leave ink marks in the other wrong bubble. The scanner will sense less reflected light from two bubbles marking the answer invalid.
Simple is that the right bubble must reflect less light than the other bubbles. The other bubbles must reflect back the equal intensity of light to the sensor.
So, how to rectify the mistake if we have filled the wrong bubbles by mistake? How to make corrections in the OMR sheet?
Three Ways to Make Correction in OMR Sheet
Well, there are three ways to make a correction.
Scratching the Wrong Filled Bubble
One way of correcting a mistake in the OMR sheet is by scratching the wrong filled bubble with the help of a blade or by any other means, but without tearing the sheet.
By scratching, we just have to remove the ink. The OMR scanner will detect no ink there and the reflected light would be equal in intensity with other empty bubbles. Thus, you will double-cross the scanner and secure your marks.
Using Blanko or Whitener Pen
The second way of making a correction in the OMR sheet is by using ‘Blanko Pen’ or ‘Whitener Pen’. Use the pen on the wrong filled circle and cover the ink. There are chances that this can also help in saving a mark.
Pasting a small piece of paper on the wrong-filled circle
You can also cover your wrong-filled bubble by placing/pasting a small white piece of paper above that circle. This will cover the ink and light will be reflected from that piece of paper.
As the proverb says,
A drowning man catches at a straw.
As you have already lost your mark with wrong filling, there is nothing wrong with trying to temper that MCQ.
Try to remove the ink from the wrong-filled bubble with the help of the above-mentioned methods.
We hope it will work in your favor!