Sunday, April 11, 2021

Technical: What is the difference between Photonis echo, 4G intens and Gen3 ??

 



Before 2019 echo have same technology and are 4G fail out.
I dont have reliable information about eventual different coating or different PSU.

After 2019 Photonis separated the Echo and 4G line in 2019.
Wich mean the echo tubes are build in a very different line what doesnt even makes them a 4G.
The 4G benefit of a specific coating with biggest spectral sensitivity.
Spectral range from 400nm to 1000nm. And a very fast autogated power supply.





Gain:
If you want to calculate the equivalent gain of a G2 to compare with G3, you should do like this:
For example 14000 gain (photonis) x pi x 1.1 (metric difference in measurement with the 2856k light)
14000x3,14x1.1=48300 equivalent gen3
You can apply the same factor for Srn.

1.1 factor:
Here à part of David 
(CJ7Hawk) text on ar15.
Quote:
Also, as a part of my research, I developed a factor ( co-efficient ) for comparing 4G tubes to Gen3 tubes directly, based on specifications which include the photocathode response in any way ( S/N, PC, Gain, etc ) since the 2856K light standard used in measuring tubes creates a different response to what is experienced in the field - as a result of atmospheric glow phenomena. It's normalized around 1.0 which represents a Pinnacle tube photocathode, as published by ITT ( Now Excelis ). - As a result of this, 4G metrics should be multiplied by a factor of 1.1 over datasheet - this means that a 4G S/N of around 32 would be equivalent to a Gen3 S/N of around 35 - This is it's Night Sky Co-efficient, and predicts the difference in field performance between the two technologies, since it's otherwise difficult to compare them. (End of quote)

Ebi:

To have the equivalence between Gen3 and Gen 2 photonis.
You can multiply the G2 value x10. And vice versa.

Photocatod sensitivity:

A 4G tube with 2200 fom was measured.
The result of photocathode response measurements on the 4G Wp was: Sensitivity >1000 ua/Im, at 830nm >130 ma/W.
This latter number is 80% more than the xr5 value. It's near to what their patent claims, it claimed a 80% increase at longer wavelengths, seems that is exactly what's happening with the 4G for reference, gen3 have still 60% more than 4G. With about 210 ma/W.

If you want to have the gen3 equivalent for the sensitivity.
In the night vision documentation (photonis, ITT...) , it's accepted that a generation 3 tube filmed with a sensitivity of 1800 is equivalent to 650 for a generation 2. Due to the ion barrier.
So you can apply a 2.77 factor.
For example the 1000 ua/lm will do 2770ua/lm in Gen3 filmed.
The efficiency of a filmed Gen3 Photocatod is 36% according to Photonis.
If you want to push your calcul you can extrapolate with thin-filmed you will save 10 to 12% of efficiency and idem for filmless.

XW: White phosphor
XX: Green

1St number :
00:basic tube
14:commercial
19: Supergen
20: XD4
25: XR5
ZG/ZW: Echo
30: 4G
31:g+

Second number:
40: inverted tube Ag
45: inverted non Ag
50: non inverted tube Ag
55: non inverted & non Ag
Ag autogated

Letter: no meaning ==> just follow up for last created tube type.







Friday, April 2, 2021

Coming Soon High light/ Low light with or without LIF

High light/ Low light with or without LIF

 In high light (urban or semi urban condition) without LIF filter, the view is brighter with a good contrast. 

With the LIF, same place, same setting, the view lost a part of the contrast, the global image seem more luminous.


 In low light (night level 4) without LIF filter, the view is more darker than semi urban condition with moderate snr and a good contrast.

With the LIF, the view is really darker with a lot of snr. The scene begin to be difficult to distinguish.





Us Carson Industries lens milspecs vs Israeli Optronics

Us Carson industries lens milspecs vs Israeli Optronics 

For this test, same setting, same tube, same eyepiece (Carson)

  • Tube GP Omni7
  • Tube Photonis 4G Wp
First Optronics, second Carson

Optonics
Carson
Optonics
Carson


  • Photonis 4G









Coming soon photonis 4G vs omni7

 Photonis 4G vs omni7

In Construction: 😉

Same caméra settings. Same housing. Same optics.
Green = Omni7
White = 4G

Due to Covid, i can't go outside by night.



Night level 3. Quarter moon. 






Technical: What is the difference between Photonis echo, 4G intens and Gen3 ??

  Before 2019 echo have same technology and are 4G fail out. I dont have reliable information about eventual different coating or different ...