MB-SUB VB50 Cave review

[Goldigger]

The aspheric doesn't appear to be smooth, it has rings in it that are very close together..

 

[DM51]

The aspheric doesn't appear to be smooth, it has rings in it that are very close together

Fresnel lens.

 

[Goldigger]

Fresnel lens.

Like they use in light houses?

 

[DM51]

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]

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..

 

[Goldigger]

Here's a slightly better video..
http://www.youtube.com/watch?v=qzidSq488Ks

How do i embed video on my posts?

 

[jspeybro]

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]

Thanks for all the info, looks like a great light.

How much are the VB50 heads and the battery packs?

 

[mbsub]

Thanks for all the info, looks like a great light.

How much are the VB50 heads and the battery packs?

Hi,

you will find the price lists here:
http://www.mb-sub.com/lampsprice/?L=2

because the affordable current exchange, the price for the total system VB-CAVE (head with battery canister and charger) today is only US$ 1050,00

Michael

 

[mbsub]

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

Yes, the optical lens is behind a 8mm glass lens.

Michael

 

[Goldigger]

Hi Michael,
Have i done enough advertizing for you now?

 

[lucca brassi]

No Goldigger ,


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 .........till next mission........

your Michael

 

[Goldigger]

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..

 

[lucca brassi]

Frensel lens : online to buy

http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=11

they are really thin ( better translucence ) and don't need to much space

 

[gcbryan]

Frensel lens : online to buy

http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=11

they are really thin ( better translucence ) and don't need to much space

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?

 

[lucca brassi]

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
.

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.

 

[mbsub]

Hi Michael,
Have i done enough advertizing for you now?

Hi Jason,

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

Michael

 

[lucca brassi]

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

 

[Goldigger]

Here's a quick video i took today of the VB-50 along side a Halcyon 21w hid.
Sorry its not great, but the first opertunity I've had..

http://www.youtube.com/watch?v=CKaQn2RQ4Co

 

[Packhorse]

A bit hard to tell due to angles and distances but it looks like the HID blows it away???