Mounting to a Gitzo PL-5 head

**pgk** · 3-May-2024, 02:03

I have a PL5 head and the period tripod it came on. On mine the tripod column top disk is not removable, so my guess is that your tripod is later than the head. Whilst I do have a brass collared screw which will work on the PL5 I've found it easier to use a long Arca style clamp fitted to the head via several 1/4" Whitworth~ (1/4" 20tpi) bolts and then fit cameras with Arca style bases. This makes life a lot easier and buying the clamps and bases off ebay means that they can be bought quite cheaply.

**Reverb** · 3-May-2024, 06:06

Thanks. I'm just bringing myself up to speed now on all this. I have an Arca clamp on the tripod I use for micro 4/3, I just didn't know it was an Arca. It's what came with the tripod (bought new), it fitted my camera, so I used it no questions asked. It was my first tripod fitting of this type. I suppose my older tripods (started with a Slik 88) predate that system.

If I've now understood correctly, 1/4" (6.35 mm in these parts) is the standard screw/bolt fitting for the underside of an Arca clamp?

My measurement of the slot for the Gitzo head is 6.8 mm at the narrowest (there's a raised rim running round the inside of the slot). That's enough clearance for a 1/4" bolt including the threads.

In the bottom of the monorail clamp is a screwhole that I measured at 9.1 mm - the Gitzo screw that fitted it is about 9.3 mm diameter from thread tip to thread tip. I'm not familiar with fractions of an inch, but I am assuming my metric measurements equate to a 3/8" connection. So I need to find an Arca plate with that size screw, and attach it to the bottom monorail clamp, is that right?

**pgk** · 3-May-2024, 07:13

Tripod screws come in two sizes. Basically, and without wanting to go too deeply into this, both are Whitworth type threads (this designates their specification) and they are 1/4" and 3/8" diameter. In the USA the 1/4" 'Whitworth' is very similar (interchangeable) to what is often referred to as a 1/4" 20tpi (threads per inch) specification. Most tripod attachments such as quick release plates and adapters use these and mostly they use the 1/4" thread, but not all as some use the 3/8". Small insert adapters are readily available to screw into 3/8" threads and these have a threaded hole in them to enable a 1/4" thread to be fitted effectively converting the 3/8" hole to a 1/4" one.

Many Arca style clamps are supplied with 1/4" bolts with a section of the thread cut away to enable them to be used in the slot you refer to, and these allow the clamp to be bolted onto the tripod head. However on the PL5 the slot is big enough to enable a 1/4" bolt (I use washers too) to bolt right through it to hold an Arca Quick Release clamp. I use a clamp which has 3/8" threaded holes and have fitted these with adapter collars which then take the 1/4" bolts and this works perfectly. So you should have no problems fitting a long Quick Release clamp to your PL5 and using a similar long plate on your camera will make life easy when putting the camera on an off the tripod.

Does this all make sense?