How about grinding the lens to a smaller size and put it inside the reflector with some adhesive at the edge.
Or there is a smaller sized lens: http://www.dealextreme.com/details.dx/sku.13908
Is it going to work?

Different aspherics have different focal lengths. I ordered some of those but they have been out of stock. Anyway grinding the lens will be very hard to do right. Much easier to cut the reflector.

The larger the focal length the further the lens needs to be from the LED. The further away the lens is the less light it will collect from the LED.
Also the larger the diameter of the lens the more light it will collect, but I think having a larger diameter lens will also increase its focal length.
Of course the diameter and focal length and probably a few other variables all play a part in determining the size of the projected image/beam

Ideally you want a lens that will collect all the light from the LED. So a LED that throws its light foward as opposed to sideways is preffered.

OK I am ordering another 4 IST's
2 for Osiris
2 for Plumb Bob

The supplier has a total of 9 in stock.
Anyone else want any?

I will also be ordering in the other parts to mod them and if we buy in 3+ or 10+ we can get discounted rates.

PM me for details.

Ok for those who ordered ISTs, I have them and the upgrade modules. I am awaiting the aspheric lenses which will be here early next week. Completed product should be dispatched soon after.

Received my lights toady, great werk Packie!! Very nicely done, though I'n having difficulty seein the kewboard cos of burnt retinas...

Wow that was quick. I posted them yesterday arvo!!

Yeah it pays to not look down the barrel as you turn them on.

Ok I gave the Modded IST lights a run yesterday as Stealth, Selina and myself went to Flea bay for a couple of dives and the last one ended up being a night dive.

All in all I reckon the light was very good, the tight beam was excellent for piercing the sometimes murky water and the brightness of it was outstanding.

Only two things detracted from the torches.

1, Don't trust the threaded securing point on the end, I had secured a snap bolt to it and in the 1st 5 minutes of the dive I lost one of the torches but luckily had a back up. So that's a fault of the IST manufacturer not PH you could probably glue the threads in or something but if you have one you must do something cos it's very insecure with only 2 tours on the thread!

2, The square beam is a little to tight for looking at critters, good for spotting em but not so good for viewing them, we saw the biggest cray i've ever seen and couldn't light up more than 1/3 of it at a time due to the beam being so tight.

That last point isn't that big a deal really as I wanted these torches as backups for my can light and as such would prefer the tighter throw to a more diffuse beam.

Sterling effort Packie!!

Got anymore?

Oh. sorry to hear you lost one! Some loctite or glue would help that for sure although I just did mine up with some pliers and never had a problem.

You are not the first to lose one on its first dive. I gave one to Osiris and he lost it in Lake Pupuke but I think he had simply not clipped it on properly as opposed to it unthreading.

My supplier has 2 left in stock and if he can get anymore there will be a price increase due to the collapse of the global economy.

I have one more of these for sale if anyone is interested.
Not yet modded so you can order it to spec.

Looks like this may be the last I can get hold of. My supplier has none left and will require me to buy 30 at a 50% increase if I want more.

Hey Mr. Packhorse,

Would it be possible for you to post some pictures of the guts of the IST, stock HS, Driver, down the tube etc. Also what is the diameter of the stock driver? Thanks I followed this from the CPF and I am thinking of doing a Cree MC-E mod on one of these.

Merry Christmas,
DD

I will when I get some time although I think a MC-E would be a waste of time. I did one with a P7. it was alot more floody than stock or with a Q5 and stock reflector & not as bright as a Q5 due to more flood. The run time was crap. You cant use a aspheric lens with it as you will end up with 4 square beams. Unless you defocused the aspheric.

The Q5/R2 mod is the best LED for these lights. Anyway if you want one stock or modded PM me as it looks like I will be buying 30 in the near future.

I have used a modified 8 degree optic that has had pretty good results. very little X and good balance between hotspot and flood. Also PM sent regarding stock unit

Well I have just taken delivery of some more IST's.
Although these look the same externally they have a different LED Probably a Luxeon K2 instead of a I . Anyway they do put out more light than previous ones and come pretty close to the Cree Q5's. Bad news is they still run of 2 3 volt Li Ions and will not run for long on 2 3.7v Li Ions.

Anyway if anyone is in the market for a modified IST with a Q5 LED, aspheric lens and bored out for a 18650 LI Ion battery please let me know. I have already pre sold about half of this order.

Some comparative beam shots
Canon G10
1/10sec
ISO 100
F2.8


Aspheric Q5

Q5 IST reflector

Stock Black wide angle intova.