RAOBF

[Trevally.]

Thanks for the help joegrundman

I think I now understand most of how this works.
I am wanting to test the clicks on the RAOBF.

I have measured the info from map.
Range = 850m
Mastheight = 28.4
zoom is x1.5

Testing range.




Mast should be at 3.5 clicks but shows 4
I use the bottom right marker for zoom x1.5

[Trevally.]

OK next I am testing range with x6 zoom
I use the 12oclock marker for this.
All values are the same as above.



Ok here we see the mast should be at 13.4 clicks but is 16clicks

[Trevally.]

Ok next testing AOB at zoom x1.5
Ship lenght is 120m
Range is 850m



So 4.5clicks x 4 = 18clicks
= AOB at 18.5deg

Actual AOB is 112deg starboard
so 112-90=22deg or 21clicks
21clicks /4= 5.25 clicks rather than the 4.5 shown.

Is this close enough for AOB
Do you think that only the vertical clicks need changing

[Pisces]

Yes, your steps are done correctly, despite vertical graticule marks being wrong.

Instead of multiplying by 4 if you use the 1.5x zoom, you can also drag the moveable wheel counterclockwise from the lower-right index to the 12 o'clock index. And then look at the AOB value aligned to the number of horizontal marks that you see on the graticule scale. That works the same.

[Trevally.]

Originally Posted by Pisces

Yes, your steps are done correctly, despite vertical graticule marks being wrong.

Instead of multiplying by 4 if you use the 1.5x zoom, you can also drag the moveable wheel counterclockwise from the lower-right index to the 12 o'clock index. And then look at the AOB value aligned to the number of horizontal marks that you see on the graticule scale. That works the same.

Thanks for the conformation and the tip Pisces

[joegrundman]

AOBs greater than 90 cannot be shown using this tool, as you realised, but stbd 112 is equivalent to 68. 68 is substantially different from AOB 20 that it gave and is not good enough for targeting.

There is something wrong with the reticule here, or else the technique for using the tool with this reticule needs to be explained further, or else remake the reticule from scratch

edit: you're Orkadian? My parents-in-law live on Orkney!!

[Trevally.]

Thanks joegrundman

I have re-made the reticule - I think I have the vertical correct.
Reading about the AOB I think I've now made a mistake based on this:-

112-90=22deg or 21clicks

If I get vertical correct I can re-do the horizontal.

Posting new test soon.........

edit: you're Orkadian? My parents-in-law live on Orkney!!

Yes Im Orcadian. Small world eh....

My home town here http://en.wikipedia.org/wiki/Stromness