MB-SUB VB50 Cave review

Goldigger

Well-known member
Joined
Mar 17, 2009
Messages
327
Location
London UK
The aspheric doesn't appear to be smooth, it has rings in it that are very close together..
vb50lens.jpg
 

DM51

Super Moderator,
Supporter
Joined
Oct 31, 2006
Messages
13,338
Location
Borg cube #51
The small concentric circles are actually refraction prisms in X-section and this allows the lens to be made thinner and therefore lighter / less bulky. I'm not sure about light-houses, but it sounds likely they would use the same principle, otherwise the lenses would be hugely heavy.
 

Goldigger

Well-known member
Joined
Mar 17, 2009
Messages
327
Location
London UK
I remember seeing a program on TV about them, they defo use them in light houses.. obviously there lighter as they can make them out of plastic to.
But it allows the light house to be able to project the light further..
 

jspeybro

Well-known member
Joined
Aug 13, 2009
Messages
586
Location
Belgium
interesting... I've been looking around for fresnel lenses because I had the idea of using fresnel lenses in dive lights, but they seem hard to find. And when you find them, they don't give you the details you need :shakehead (positive/negative, focal length,...)
Lighthouses indeed use fresnel lenses.

I suppose the fresnel lens is behind a flat glass/plastic lens?

I guess I'll need to look at suppliers of optics to find what I want.
 

The Magpie

Well-known member
Joined
Jun 25, 2009
Messages
62
Thanks for all the info, looks like a great light.

How much are the VB50 heads and the battery packs?
 

lucca brassi

Well-known member
Joined
Feb 1, 2008
Messages
885
Location
Kocevje , Slovenia, Europe
No Goldigger , :knight:


Now you have to update Scubaboard , DirExplorers , DecoStop , Cave Divers, Rebreather's World , yorkshire-divers , Taucher's Net , Pressluftflacche.de , and then you 'll be relesed from my claws :devil::devil: for a while :dedhorse: .........till next mission........

your Michael
 

Goldigger

Well-known member
Joined
Mar 17, 2009
Messages
327
Location
London UK
I've done Yorkshire divers, there's a thread on direxplorers that i could hijack.. :)
But the DIR guys were pretty clear and said that it wasn't DIR, so they might not be the correct audiance?

Update
Direxplorers and scubaboard are now in on the review..

Michael i expect a xmas present this year if your sales go up.. :)
 
Last edited:

lucca brassi

Well-known member
Joined
Feb 1, 2008
Messages
885
Location
Kocevje , Slovenia, Europe
I want to focus on frensel lens below aspherics lens similar to VB50. There are several typs (aspherics frensel , classic frensel made from glass or acryl) Cheaper acryl with diameter arround 2'' has price 25-29$ that mean 20-24€.

Yes quality optics is not cheap , but even MB-SUB must have some argumentation for price of head which is 495€ if you want to implement on your system (adapter+cable +VB50) . I think profit there is quite absorbing
:sssh:.

For instance twin cave is much more complicated head for machining , it have two ostar leds which is each expensive at least as one SST-50 , reflectors , solid switching mechanism (instead of ring magnet) then electronics but it is 10€ cheaper !!!

Have you ever tried any of the Edmunds aspherical lenses at $35-$45 and compared them to the DX lenses at $2.00?

I'm wondering how much better they are?

No , but I'm quite sure that quality light is product of common quality (construction of housing , machining housing (thermal managment ), optics, electronics, and hand composing it together). Because of that reason it is very hard for DIY to get same or better results on modified hand flashlights like maglite or similar.
 
Last edited:

mbsub

Active member
Joined
Dec 23, 2007
Messages
44
Hi Michael,
Have i done enough advertizing for you now? :D


Hi Jason,

thank you for your helpful advertizing.
Because we are only a small company, we need this kind of advertising.

Michael
 
Last edited:

lucca brassi

Well-known member
Joined
Feb 1, 2008
Messages
885
Location
Kocevje , Slovenia, Europe
I completly understand MBSUB needs on advertising ,because market is small and limited and product has high price , but Germany itself has a lot of scuba lights producers.

...but this is in princip DIY forum where people like to analyse products and squeeze out useful information to reduce their cost and made DIY product better if it is possible.

regards
 
Top