Series 7 lens adapters

[Stressball]

Hi all, nice to be a part of this forum finally :)

I'm having a bit of a predicament, I've just recently bought a cheapo fisheye lens adapter for a toy off eBay, with Series VII 49, 52, 55 and 58mm adapter rings. When I bought this lens adapter, I was still using my Pentax K100D with a 58mm diameter lens, so it was compatible. After I paid for the fisheye, I bought a Canon 40D with a Tamron lens of 62mm diameter. The lens to adapter connection is male - female, which leads onto a male 49/52/55/58mm connection. My question is, does anybody know what the diameter of the lens-to-adapter connection is?

I have attempted to hold the lens connection against the 49/52/55/58mm male connections for a comparison, and it appears to be between 52 and 55mm?? I'm not sure if it is either one of these, or if it is a particularly special diameter to ensure you can only use Series VII adapter rings with this lens or something of the sort?

The lens is here: http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&rd=1&item=160234197791&ssPageName=STRK:MEWN:IT&ih=006

Any help would be greatly appreciated, as I am also having this same problem with a macro ringflash I have bought that fits the same adapter rings. I do not know the X - 62mm adapter I need to buy to get both of these to fit properly.

Thanks in advance!

[Jon]

The "Series" filter sizes don't correspond directly with any "mm" filter sizes. The "Series" designations have been around for years, generally with threadless filter discs held in a "sandwich" holder. It actually predates the current system but has fallen out of favour. You'd need a 62 mm Series VII adapter, but for a 58 or 62 mm filter-size lens, you really would need Series VIII; Series VII is about a 50 mm filter; series VIII is 63 mm; you're risking vignetting (which helps the fisheye maker "cheat" in the effect a bit) with the smaller size.

[Stressball]

Thanks muchly!

I know the fisheye adapter will get some vignetting with it wide on that adapter, however it's really just a toy to do some experimenting so it doesn't bother me too much.

As well, it will be ok for the most part with the macro ringflash I've bought, as I won't often be shooting full wide anyway. I do not have a dedicated fixed-length macro lens, so I can adjust it if necessary.

Thanks for your help :)

[foxbat]

I can't quite work out your question but if you are asking "what size is Series 7" then the answer is 54mm.