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Posted on 20/04/23 10:04:46 AM |
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DavidMac
Director of Photoshop Posts: 4936 Reply  |
CALCULATING REFLECTIONS
One thing that has bothered nearly all of us at one time or another when photoshopping is the creation of reflections. Steve has often had to point out errors in this sometimes tricky and baffling area. Indeed it's included in his common mistakes section in Photoshop London. So here's a little test of just how well you have understood his reminders that angle of incidence and and angle of reflection are equal. This isn't a trick question. It's a genuine question with a proper rational answer. This is for you too Steve!! I am standing upright on a level horizontal floor in front of a mirror on a vertical wall. The height and size of the mirror are such that in reflection the top of my head coincides exactly with the top of the mirror and the bottom of my feet with the bottom of the mirror. If I step back from the mirror, will space open up above and below my reflection or will I start to become cropped? If you are guessing or relying on instinct, which I suspect many of you may have to, please say so honestly. It will be interesting see where that takes us. If you think you have a good reason, or even better a proof, for your answer say so as well, but don't give it away. Leave a level playing field for the others. You will find out later if your reasoning was correct when I publish the answer and explanation. So come on guys and gals! Let's see what you're made of! _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 21/04/23 07:14:45 AM |
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Steve Caplin
Administrator Posts: 6835 Reply  |
Re: CALCULATING REFLECTIONS
That's a very interesting question. My first instinct was to say 'cropped', but it requires some more thought. I'm just about to write up the Friday Challenge, I'll take a look at this problem after that. |
Posted on 21/04/23 08:35:46 AM |
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Steve Caplin
Administrator Posts: 6835 Reply |
Re: CALCULATING REFLECTIONS
OK thought about it. I'm now saying space above and below. But I might just have to get a mirror and try it out. |
Posted on 21/04/23 10:50:09 AM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
OK folks. Steve's broken the ice. Anyone else brave enough to try a dip? _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 23/04/23 10:11:20 PM |
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Frank
Eager Beaver Posts: 1576 Reply  |
Re: CALCULATING REFLECTIONS
David, my guess is space below but head line remains the same - however the reflection diminishes in size as you step further back.  |
Posted on 24/04/23 09:38:11 AM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
Good to see someone else here! I'll publish the answer in a couple of days. _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 24/04/23 11:48:29 AM |
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Frank
Eager Beaver Posts: 1576 Reply |
Re: CALCULATING REFLECTIONS
Hope we don't get "DETENTION" if we're wrong!  |
Posted on 24/04/23 2:43:47 PM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
When I was boy it would have been loss of sports time. Write "The angle of reflection is equal to the angle of incidence." one hundred times while watching the other boys outside playing cricket. Mind you, because of my poor eyesight, and the consequent bruised fingers, I hated cricket (one of the several deplorable and nearly treasonable ways in which I am not a true Brit) and some detentions were almost welcome.  _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 25/04/23 8:36:23 PM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
Since it appears that no-one else is going to be forthcoming here is the answer. I had hoped for a few more opinions but it is not an easy question .......... I hope the explanation I have put together here is clear, as the answer may not be quite what you expected.  _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 26/04/23 12:25:20 PM |
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lwc
Hole in One Posts: 2627 Reply  |
Re: CALCULATING REFLECTIONS
I came into this late and still got a headache thinking about it...  |
Posted on 26/04/23 1:46:40 PM |
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GKB
Magical Montagist Posts: 3723 Reply  |
Re: CALCULATING REFLECTIONS
I was going to wade in on this but, on reflection, I won't. _________________  |
Posted on 26/04/23 9:44:58 PM |
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michael sinclair
Off-Topic Opportunist Posts: 1751 Reply  |
Re: CALCULATING REFLECTIONS
That's remarkably clever of you David. Tell me, can this information be obtained elsewhere? I'm sure Steve will profit from it. Sorry! What? Oh, what will we call it? The Macdonald Phenomenon PS I've replied to your Korean debacle post  |
Posted on 27/04/23 10:35:06 AM |
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Frank
Eager Beaver Posts: 1576 Reply |
Re: CALCULATING REFLECTIONS
Somebody turn on the lights. |
Posted on 27/04/23 5:34:45 PM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
You were quite close Frank. You got the constant headline. _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 28/04/23 08:10:44 AM |
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Steve Caplin
Administrator Posts: 6835 Reply |
Re: CALCULATING REFLECTIONS
Well this is extraordinary. I must find a mirror and try it. |
Posted on 28/04/23 09:01:57 AM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
I haven't actually tried it but the theory does seem to hold water. _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |
Posted on 28/04/23 10:51:32 AM |
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DavidMac
Director of Photoshop Posts: 4936 Reply |
Re: CALCULATING REFLECTIONS
I've tried it now and it works exactly. I have a mirror at the end of a long corridor and I tested from about one meter to about ten metres. _________________ The subtlety and conviction of any Photoshop effect is invariably inversely proportional to the number of knobs on it ....... |