[grhazelton]

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I'm thinking about buying a focus rail for use with my 645n or my LX. Given the weight of the 645 with the 120 macro I'm concerned about the strength of the rail. Adorama offers this unit MFRSS Adorama Macro Focusing Rail Set, 4 Way, Fine Control, Camera Focusing Rail to Aid in Tripod Mounted Macro Photography.

and a call to Steve at Adorama reveals that the rail is made of metal, unlike their other offerings, which are plastic. I presume that the gears and lock knobs are metal, though. Steve had no info on weight capacity.

So like the true skinflint that I am I hit EBay and found this listing: 4 Way Macro focus Rail Slider f Canon Nikon Pentax SONY | eBay

Which certainly looks exactly like the Adorama unit! It is stated to be made of metal. No weight capacity is stated. Anyone have experience with either ot these rails? Any suggestions for other units?

[Jools]

I use one of the ebay knock offs and it works quite good as long as the camera remains in a horizontal or near horizontal position. The moment one begins to alter the camera's position, the gears get harder to move forward or backward. It is especially noticeable when the camera is pointed downward or above the subject. So this is an issue for specific movement of the camera or precise focusing like in stacking.
I don't use nor know the weight of a 645n but use a K200D with and without the battery grip with ebay 4way rails.
My guess is that the 645n would be too heavy for this 4-way rail. With my setup, I can get frustrated. Will invest in something more reliable but for now this one suits me fine.
Good luck.

[excanonfd]

So like the true skinflint that I am I hit EBay and found this listing: 4 Way Macro focus Rail Slider f Canon Nikon Pentax SONY | eBay

Which certainly looks exactly like the Adorama unit! It is stated to be made of metal. No weight capacity is stated. Anyone have experience with either ot these rails? Any suggestions for other units?

Exactly what I was going to say; what Adorama is selling for 180 or 70, they are probably the same as the one you found on eBay for 33 bucks. They're all made in China now, I don't see why you would want to spend double or considerably more for a generic Adorama brand. I bought two single rails for my K20D and I had my Canon FD 200/4.0 macro mounted on it as a four way control rail and it works. There is no noticeable stuttering when the rail is being extended, just the knob on my single rails are very skinny. I think I will buy the four way rail you found on eBay, there is a lot more clearance between rails and the knobs for easier manipulation of the rails.

Thanks,

[jimpurcell]

I bought a cheap ebay version. I will sometimes use it for my K5 and other small cameras. It is enough of a hassle that I wouldn't even consider putting it under my 645d. The problem is the mechanism for movement isn't micro enough. That's the first problem I would deal with.

In short. If you KNOW you are going to use it. Spend the money for a great one.

[Helen Oster]

........a call to Steve at Adorama reveals that the rail is made of metal, unlike their other offerings, which are plastic. I presume that the gears and lock knobs are metal, though. Steve had no info on weight capacity.

Should've asked me.... it's 5 pounds

[grhazelton]

Oops! Sorry, Helen, for forgetting about you.

[Helen Oster]

Oops! Sorry, Helen, for forgetting about you.