Aspheric lens for a C8 ?

Has anyone fitted an aspheric lens to a C8 for greater throw?

Is it a worthwhile mod, and indeed can you get an aspheric lens to fit a C8?

Dave I have the same doubts as you. I´m interested in this lens too.

It would be worthwhile. People do similar things with Mags all the time. I’m not aware of any off the shelf aspherics with the right diameter and focal length for a simple drop-in though.

I don’t have a C8 but do have a HS-802. Is that about the same diameter as a C8? I ground down a larger aspheric so that it would fit that light but focal length is the other issue. I had to muunt the aspheric halfway down the barrel of the head.

I also have a 50 mm aspheric that I haven’t used for anything yet. The concept is no different than the DBS or Tiablo aspherics however. I’m still referring to XR-E’s however for best results.

Why do it when you can buy a Flood to Zoom from Manafont for $14.90.

I'm not to sure!!! Will they give the same beam pattern?

I’ll let you know in a week or two since I just ordered that! I just depends on the quality of the aspheric that you use and of the host that you put it in as to whether one is better.

When you pick your own host you can pick a better constructed body than most of the cheap zoom lights use. In a twist rather than push/pull light those may work quite well. I have two different twist versions on order.

For the most part however those zoom lights just don’t seem to be constructed very well. Until recently there weren’t larger sized aspherics in those zoom lights.

This lens should fit a C8 class head.

Too bad they are sold as a five-pack only, a bit too many for a first experiment.

I was thinking of trying the same thing, but came across the Small Sun ZY-C10 pictured above, and I have now that one on the way.

GCBrian- will be intersted to see your impressions of the twist zooms when you get them .

Which models are they- seems like the twist types which I prefer for stability/quality are more rare than the push pull ,imprecise types.

They do seem to be more rare. Many who like zoom lights like the fact that will push/pull you can use one hand.

I’m interested more for the throw and I don’t want that setting to move so easily when I put the light in my pocket so twist is better.

It now looks like only one is twist as the other was mis-advertised.

The twist model arrived today and here is a link to my review.

Review: Cree Q5 270 lumen 3-mode twist to focus LED flashlight with side switch (18650)

By the way, this twist model and be used one handed quite easily.

FWIW, has a Jaegers 41mm diam., 35 mm FL for 4.50 US, a Pyrex 44mm diam., 30mm FL for 6.00 US, and a double convex aspheric 44mm diam. 30mm FL for 5.00 US. Shipping is a flat 5.00 for an entire order. More expensive than some, cheaper than others, somewhere in between. Probably good quality; I don't have any of the three myself.

Do those lenses have a flange?

I'm only getting ready for my first aspheric mod, but I think the flange makes the job much easier. I also doubt if a double-convex lens would be suitable for this task.

Yes, they do have a flange, which should make grinding to size somewhat easier. I agree about the DCX, although someone in another thread (I haven't searched for it) did use a DCX successfully.

"For shipments going to Hawaii, Alaska or countries outside the U.S., we will e-mail shipping option prices for your approval prior to processing your order " This what they say about shipping outside the US.

Speaking of grinding to size: what are the recommended methods?

Any specs on these lenses ?

Specifically the BFL, or Back Focal Length is of particular importance.

The best way that I have found is to use a conventional bench-top grinder, resting the lens flat side down on the provided support in front of the wheel,with a piece of thin cardboard under the lens to prevent scratching. I bring the lens against the wheel and rotate it horizontally as methodically as I can to try to maintain a circular shape. A fairly slow process but not too bad; nonetheless,I hope someone has a better way.

ChicagoX, thefirst one (Jaegers 41diam./35FL) has a back FL of 30mm, 15mm center thickness,3mm edge thickness. For the second (Pyrex 44diam.,30 FL ) no back FL given,14 mm center thickness, 2.5 mm edge thickness. The last one, the DCX, again no back FL given, 17 mm center thickness, 3 mm edge thickness. All this from their website, again, I don't yet have any of them. Given the $5.00 flat rate shipping I may order all three for 20.50 rather than one for about 10.00. Spend money to save money.

Wow, if a lens can stand that, then dremelling radially (that's what I had in mind) should be plenty safe.

I found dremelling to be very very slow, but I think it would have worked if I was more patient. The grinding wheel does create excessive heat if the lens isn't kept moving or "backed off" periodically.

I don’t have a bench grinder or a Dremel tool but for a while I had access to a friends bench grinder and I did it exactly as mentioned above.

It does get hot so you have to back off every now and then and you need to constantly get turning it. It’s not hard to do however.

I think it would be hard to do with a Dremel with the smaller head size but it’s worth a try.

It helps to know that one doesn't have to be too concerned about cracking the lens or chipping its edges.

I thought it was a very delicate job.