@radiologytutorials Awesome, thanks a lot. These videos are as simplified as it gets, got a hang of the topic. Can you post a video on spotters and long & short case discussion which would be helpful for our practical exam. Thank you
Thank you 🙂 Can you please explain " latitude and contrast of a film are inversely related" through characteristic curves of film a and film b given in the book .
The wider/bigger the latitude the less contrast there will be in the image - a greater range of exposures will lead to smaller changes in optical density. A steep characteristic curve has a narrower/smaller latitude - therefore smaller changes in exposure lead to greater changes in optical density (ie more contrast. Hope that makes sense 🙂
@@radiologytutorials Thank you Dr.Nel Can we say for a single film (where slope of characteristic curve is constant) increase in latitude has no effect on contrast ?? When we are comparing two films( where with change in slope of curves )latitude and contrast are inversely related. I am sorry , I am confused🙃
The slope of the characteristic curve is what determines latitude. Therefore for an individual film the latitude cannot be changed (and contrast in that film is determined by the latitude and exposure). So you are correct - when comparing two different films we say that latitude and contrast are inversely proportional 👍🏼
@@radiologytutorials can't we change the latitude of a film by changing range of exposures? Suppose if I change the range of exposures from 0-1 to 0-2 , the range of optical density will also increase right??
Slope=y2-y1/x2-x1 For a single film , slope is constant ( atleast between toe and shoulder region). Can't we say increase in exposure should be accompanied with increase in range of optical densities, so that contrast for a given latitude for a film is constant, even though if we change the latitude (range of exposures )?. Thank you for your patience and knowledge Dr.Nel❤️
High exposure leads to more silver deposition on the film. Where silver has been deposited on the film light is prevented from passing through (from the light box behind the film). This results in a dark region on the radiograph. If you think about how lungs look on a radiograph (dark), this is because X-rays pass easily through lung (unattenuated) and therefore there is higher exposure on those regions of the film. Hope that helps 🙂
great effort.. thanks and I hope you could cover more of the medical imaging physics
@radiologytutorials Awesome, thanks a lot. These videos are as simplified as it gets, got a hang of the topic. Can you post a video on spotters and long & short case discussion which would be helpful for our practical exam. Thank you
Amazing explanation ❤
Thank you!
Thx for the effort please keep posting
More to come! Thanks for watching Mahmoud ☺️
Question please...list 5 types of information obtainable from sensitometric curves
After shoulder does the curve slope down or does it just go exponentially towards infinity ?
such a soft tender voice! Feel like a baby in KG
Thank you 🙂
Can you please explain " latitude and contrast of a film are inversely related" through characteristic curves of film a and film b given in the book .
The wider/bigger the latitude the less contrast there will be in the image - a greater range of exposures will lead to smaller changes in optical density. A steep characteristic curve has a narrower/smaller latitude - therefore smaller changes in exposure lead to greater changes in optical density (ie more contrast. Hope that makes sense 🙂
@@radiologytutorials Thank you Dr.Nel
Can we say for a single film (where slope of characteristic curve is constant) increase in latitude has no effect on contrast ??
When we are comparing two films( where with change in slope of curves )latitude and contrast are inversely related.
I am sorry , I am confused🙃
The slope of the characteristic curve is what determines latitude. Therefore for an individual film the latitude cannot be changed (and contrast in that film is determined by the latitude and exposure). So you are correct - when comparing two different films we say that latitude and contrast are inversely proportional 👍🏼
@@radiologytutorials can't we change the latitude of a film by changing range of exposures? Suppose if I change the range of exposures from 0-1 to 0-2 , the range of optical density will also increase right??
Slope=y2-y1/x2-x1
For a single film , slope is constant ( atleast between toe and shoulder region).
Can't we say increase in exposure should be accompanied with increase in range of optical densities, so that contrast for a given latitude for a film is constant, even though if we change the latitude (range of exposures )?.
Thank you for your patience and knowledge Dr.Nel❤️
Hello Sir,
Is there any change on the appearance of the x-ray film after the point of solarization?
How does high exposure have less transmission?
High exposure leads to more silver deposition on the film. Where silver has been deposited on the film light is prevented from passing through (from the light box behind the film). This results in a dark region on the radiograph. If you think about how lungs look on a radiograph (dark), this is because X-rays pass easily through lung (unattenuated) and therefore there is higher exposure on those regions of the film. Hope that helps 🙂
@@radiologytutorials it all makes sense now. Thanks a lot sir
exellent
Thank you Ali ☺️
High OD will appear bright or dark on image?
Dark
1:46 you mentioned the higher the OD the more opaque and, the lesser the OD the more transparent.
He said that wrong . Just checked on internet . I too got confused in video