In my experience with the Nikon 1 system, one issue that I was looking to avoid was having to spend $500 to get a lens wider than 10mm. As a result of having lots of ebay bucks this past quarter and nothing compelling to spend them on, I decided to perform an experiment to see if I could pick up a front-mounted wide angle converter for use on the 10mm lens to give me something in the neighborhood of 6.5 to 8 mm in a small, inexpensive package, which produced acceptable results. One thing that I quickly noticed was that many of these converter lenses sell for almost nothing on ebay - and others are being sold with rather ridiculous asking prices in the multiple hundreds of dollars. Now that might be realistic if one was buying a converter that had actually been designed for the base lens, and would therefore be a relatively known quantity - but since these were going to be re-purposed for a lens that they definitely had not been designed for, I decided right off the bat not to consider any converter that I couldn't get for $25 or less. During the past couple of weeks, I picked up several of these, and also had a couple lying around from other purposes which I threw into the test as well: Among those I tried were: Sony VCL-MHG07 0.7x cost me $21 fits 52mm threads Sony VCL-R0752 0.7x cost me $6 fits 52mm threads JVC GLV0752U 0.7x cost me $7.50 fits 52mm threads Raynox DCR-6600 0.66x HD cost me $10 fits 55mm threads (52mm size also available) Fujifilm WL-FXE01 0.76x cost me $12 fits 43mm threads Digital Optics 0.5x Pro High Definition with Macro - had it already from an older camera - fits 62mm threads Each of these needed to be adapted to the 40.5mm filter threads of the Nikon 1 10mm lens via step-up rings. Right off the bat, from a practical perspective, the Sony VCL-MHG07 and the Digital Optics converters were too big, heavy and bulky to be practical. The Digital Optics weighed 10.5 ounces, and the Sony was almost 5 inches wide and weighed close to a pound. I immediately sold the Sony, and happily, sold it for more than I paid for it, covering my shipping and ebay costs as well. The Digital Optics converter was surprisingly sharp across the frame, although it had substantial barrel distortion and was large and heavy enough that I would not have been willing to carry it around in a Nikon 1 kit, and I'd be worried about over-taxing the focus mechanism of the 10mm lens. As for the others: The Raynox DCR6600, I had high hopes for, as I had heard good things about it when used on some DSLR lenses by other folks. Unfortunately, when mounted on the 10mm lens, it exhibited noticeable field curvature, and only roughly the middle 2/3 of the frame was sharp enough to be useable for subject matter that one wanted to be in focus. Also, unlike each of the other lenses, it exhibited not barrel distortion, but surprisingly, pincushion distortion, as apparently, the optical formula over-corrects the barrel distortion typical of these wide converters. As I got this for MUCH cheaper than it normally sells for, I'm pretty sure that, like the Sony, I'll be able to recoup all of my costs on this and more when I sell it. Weighs 6.5 ounces. The JVC GLV0752U, performed almost exactly like the Raynox, in terms of field curvature and lack of sharpness at the extremities, except that it exhibited the typical barrel distortion - albeit not extreme - as opposed to the pincushion distortion of the Raynox. Probably not worth selling, as I doubt I'd get much more than the cost of shipping for it. Usable in a pinch, but only if I did not mind significant edge blur due to the field curvature. Weighs 7 ounces. Sony VCL-R0752: Along with the Fuji, this was the smallest and lightest converter tested - weighing a mere 2.5 ounces: This lens exhibited the most pronounced fisheye effect of all the converters tested. The effect was easily de-fished within Adobe Photoshop Elements. Unfortunately, like the others, it exhibited field curvature which prevented any sharp subject matter outside of the center 2/3 of the frame. Again, usable in a pinch, but only if one did not care about significant edge blur, and was willing and able to de-fish the results. Fujifilm WL-FXE01: Another converter I had some high hopes for based upon a prior review. First of all, this converter required some surgery to be able to be mounted: It comes with 43mm filter threads, but the rear mount ring extends about 2mm beyond the threads. Fortunately, this extension extension is made of relatively soft plastic which needed to be filed down to the threads in order to be able to mount a 40.5 to 43mm step up ring. This was relatively straightforward to do, and it took me about 10 minutes to do this - fortunately, the rear element is somewhat recessed, so when filing the soft plastic down, one is not particularly close to that rear element so it can be done safely. Suffice it to say that this is worth the effort. This was BY FAR the best converter I tested. It was also quite small and light, weighing only 3.5 ounces. After this filing operation was completed, this exhibited very slight vignetting in the extreme corners, but was usably sharp at the edges of the frame, as well as good in the center of the frame - Thus, this converter actually DOES make the 10mm lens into a useable 7.6mm f2.8 lens. Barrel distortion from the converter was very much under control and quite small. The best thing is, there are a couple of vendors Beach Camera, and Buydig, that are selling these converters for $12 on ebay right now, and they each have several of them. If you have the 10mm lens, this might be the best $12 you can spend: Here are a couple of test shots straight out of the camera - the subject matter is dull, but quite useful for the purpose of this test. I didn't bother to post any of the shots with the other converters, because, quite frankly, they were nowhere near as good. But this Fujifilm wide converter is, to me, DEFINTELY useable as a means of getting wider than 10mm. The first shot is with the Fuji Wide Converter on the 10mm lens, the 2nd shot is the 10mm lens by itself. Both of these were shot at f5.6, but the results are similar from f2.8 to f11.