That 12mm is $254 on that link!! Cheapest I've seen for that one. These lenses are for 1" sensors. All the other cheap CCTV lenses are for 1/2" or 2/3" so that looks like they need to be 26mm+ to cover the sensor while that 8mm almost covers .
Using a longer lens and wideangle adapter with apertures of arround F2.0 is nonsense - I have tryed it and IQ is horrible. It just doesn't work.
But I think it is absolutely possible that its a modified Kowa LM8HC - it looks VERY similar. Teleconverters can deliver sharp images and the 8mm seems to already nearly cover the m4/3 sensor (as shown in the other thread). With a 1.5 teleconverter it would definitely cover m4/3, even putting any distortion at the corners outside the sensor. Only apperture would not be F1.6, it would more be like F1.7 - but I have no idea how to really test this small difference.
Finding the right teleconverter, putting everything together to make a solid lens is not easy and some effort. And the Kowa does cost arround $300, so adding $200 for the teleconverter and effort is not absolutely over the top - it isn't cheap either.
As I don't have the lens, I can't test it - but someone with the lens in there own hand can try to seperate the rear element form the rest of the lens. If thats a 1.5 teleconverter and a 8mm lens - the SLRmagic might be a little rip off, but that doesn't matter. It would be much more interesting to be able to use the whole Kowa lens series with a teleconverter on m4/3 cameras ;-)
I think it is very interesting how this lens was designed and built, but not for the bashing, more out of pure technical curiosity.
Just a summary of stuff here. 1. Add a 0.45x WA to the 25mm. Per my knowledge there is NO 0.45x WA on the market. All the 0.45x WA lenses have a WA and a rear macro element. The macro element is essential to focus but converts the 0.45x to a 0.7x. 2. A new lens design. Designing lenses is not very easy. There only about a dozen manufacturers around the world who actually design *quality* lenses nowadays. Mainly in Japan and Germany. I would suggest reading some papers on lens design to see why a lens with corner sharpness is hard to design, and a wide fast lens with corner sharpness is harder still. 3. Tele added to Kowa 8mm. A quality tele is easier to design than a quality wide. So this can be a possiblity. 4. SLR Magic is a fraud because its a one man shop in HK. Screw you mate. I don't like commies but the chinese govt have a space program that actually works (as opposed to NASA which is a bureaucratic mess), and I knew some brilliant chinese post-grad students in my MS classes.
>A new lens design. Designing lenses is not very easy. There only about a dozen manufacturers around the world who actually design *quality* lenses nowadays
They could just ask Kowa or other quality CCTV lens manufacturer to made lens according to specifications. It really can be some lens with added lens group acting as tele converter.
Vitaliy. Lens design involves more than just entering specs into a computer and receiving a blueprint. The Kowa 8mm lens has 120 lpm in center and 80 lpm at the corner. Thats a big difference between center and corner sharpness. To improve this requires more glass elements. This would increase the light loss. Adding correctional elements also changes the optical properties of the original glass.
Also adding a tele would increase the difference between corner and center sharpness as well as adding light loss. This is why the Oly 12mm lens costs so much.
Finally a lens optimized for 1" coverage requires a major rework for 1.33" coverage. Lens designs do not always scale so well. Otherwise, Nikon and Canon would manufacture the same lens for every single sensor size from 35mm to 1/4-inch.
Can't comment much yet. Metal lens. Not up to the Vivitar Series 1 or Canon FD L standards, of course. As you know it has aperture ring on the front as on most industrial lenses. Do not like it.
My lens has a problem, mount is not attached properly, it wobbles.
Lens is absolutely usable at F1.6, despite heavy chromatic abberations (they are down at about 2.8, at 2.0 still strong).
Just finished this with very intensive use of the Noktor 12mm. My lens wobbles as well. The yellow ring is very annoying when using filters. Why is it yellow!!? Should be black! But besides that. I LOVE the lens.
I removed focus ring screws (btw it is hold by this screws simply by friction :-) ) Tried to fix mount, but SLRMagic become so afraid, so they refused to help me or provide any information. Said that they'll send new lens as it'll be ready.
If I'll have some time on weekend I'll try to remove mount and try to fix it.
So here's a promo I shot with the SLR Magic 12mm that I just received today. I ran into a problem with it, but I fixed it. I'll tell you all about it later. Shot with @Driftwood Aquarius hack (hell ya your settings are on TV 20 times a day!)
@stonebat there is just a little play in the mount, nothing terrible. I tightened the screw but it didn't fix it. The big problem I had was that the screws holding down the focus ring were loose. The ring came loose in 5 minutes of playing with it and was free spinning, so I had to get a really small screwdriver from engineering and correct it, took a little bit but I got it corrected. It was weird, I screwed it back down the first time and realized I couldn't focus as far but I could focus closer. I would tighten, turn, loosen, and repeat to correct it.