Comments

• Ned Horning August 13, 2015 at 7:01am

  Hi Mario - I ran your image through  my calibration plugin and this is what came out. I used the same calibration coefficients I generated using some DIY targets and likely totally different conditions but I'm curious if the results look half reasonable to you. I'm more interested in the relative change across the image rather than absolute NDVI values. I  expect the calibration parameters will work for other camera settings to a point but I would like to test to see how broadly they can be applied.

  

  
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  Vega Tech Group LLC August 13, 2015 at 5:40am

  Mario, A lot of chromatic aberration in that image. A good lens for UAV's will not need to be refocused. You can set it and get clear images no matter the height over the object.
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  Mike T August 12, 2015 at 4:48pm

  Thanks Mario! Looks good, it is a bit blurry.
• Moderator

  MarioSpeedwagon August 12, 2015 at 1:10pm

  Still trying to get the focus right, but here is a single image from the MAPIR over a stubble field. 

  Blurry, but getting better. It's a lot of trial and error to get it set for 118m. 
• Ned Horning August 12, 2015 at 7:20am

  I just posted a long-winded discussion "The right tool for the job" to throw my thoughts of this recent discussion into the ring. I welcome feedback and comments.
• RG August 11, 2015 at 10:46pm

  Is it just me or anyone else finding it difficult to follow all these conversation on the comment wall on this group? Why don't we create appropriate threads in the forum which makes it easier to follow..?
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  Vega Tech Group LLC August 11, 2015 at 8:09pm

  Index in NDVI is a set of numbers assigned to various aspects of what is radiometrically imaged from water to green plants. Originally used to determine green plant viability.
  
  A single sensor can be used but a monochrome would give the best results allowing utilization of the entire sensor. However well designed multi sensor cameras will provide faster and more accurate results.
  
  I have used machine vision cameras to also inspect and sort food for a number of years.
  
  There are a number of indexes to determine food health & viability.
  
  Currently some vineyards are using LWIR to determine the water content of their grapes.
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  Jacko August 11, 2015 at 7:34pm

  Well, lets have a conversation about what the differences between these systems might be.

  I'll volunteer to put my neck on the chopping block and start that conversation............

  
  My understanding is this maybe something like.

  1. What 'index' means in NDVI or rather wraping some numbers around our data to obtain a value of variance?
  2. Can a single sensor system, with or without a Bayer filter, ever give anything that could be called an index?
  3. Would an agronomist base a decision on $M1/2 worth of cotton using data from a $300 sensor or is this type of thing more of a (potentially useful) general crop heath scouting tool?

  I think the potential conflict here is some people are talking about point 2. above and some are talking about point 3.

  Any one care to reply? (Neck still on the block and I'm sweating now!!)
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  Vega Tech Group LLC August 11, 2015 at 7:14pm

  I am not selling anything. I am offering information that will eventually trickle down to this market, 10-15 years from now. MAPIRS imaging is what I worked on about 15 years ago.
  
  My newest Visible/NIR/SWIR lens covering 400-1700nm is $1800. No one here can afford one, however it is in a design in to replace the PVS-14. It will trickle down this market in 10-15 years.
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  Greg Nuspel August 11, 2015 at 6:53pm

  You have to understand that many are starting out so budgets are tight. No one is saying the stuff you are selling isn't of higher quality. If a person is well established I am sure that they would be happy to invest in such equipment and maybe even better. It's like trying to sell an Arri to a student filmmaker. It is a waste of time for both involved.