Mounting my camera on SWSA GTi

[a6400]

Hi,

I have a lens collar and want to mount it on swsa gti.

I suppose I need a dovetail bar with some kind of screw?

https://imgur.com/a/hohmBiQ

[Elp]

You need to think ahead. Are you just mounting the camera body or will you want to autoguide the setup in future?

The simplest method is using a vixen doevetail bar and the appropriate sized and length bolt to fix the camera. Note, if the lens you're using is long/heavy you may find it rotates under gravity when at certain angles, then you need to think about adding in physical stops or traction under the camera body to stop the rotation. There are many different ways to mount equipment, you also have to be mindful of declination balance.

[a6400]

3 minutes ago, Elp said:

You need to think ahead. Are you just mounting the camera body or will you want to autoguide the setup in future?

The simplest method is using a vixen doevetail bar and the appropriate sized and length bolt to fix the camera. Note, if the lens you're using is long/heavy you may find it rotates under gravity when at certain angles, then you need to think about adding in physical stops or traction under the camera body to stop the rotation. There are many different ways to mount equipment, you also have to be mindful of declination balance.

The collar is on the lens because it’s very front heavy. I don’t see how would the camera rotate? The camera can’t rotate unless lens does.

Question is what screw do I need for the vixen dovetail hmm

[Elp]

If you're only going to fix the lens collar to the dovetail via one bolt there's a chance the whole setup can rotate in declination, trust me I've seen it happen. You need two fixing points to stop rotation.

Measure the hole diameter on the bottom of the collar, likely it's a photo 1/4 inch 20 tpi (unc thread) but it could be metric. Length you can determine yourself by measuring.

[a6400]

3 hours ago, Elp said:

If you're only going to fix the lens collar to the dovetail via one bolt there's a chance the whole setup can rotate in declination, trust me I've seen it happen. You need two fixing points to stop rotation.

Measure the hole diameter on the bottom of the collar, likely it's a photo 1/4 inch 20 tpi (unc thread) but it could be metric. Length you can determine yourself by measuring.

But then it will be attached by 1 screw and might be unsafe as you said. Any other idea what I could try?

 

[a6400]

I just found this, which should work with the collar, but the price...

https://www.rothervalleyoptics.co.uk/adm-dvpa-azgt-dv-series-dovetail-adaptor-for-skywatcher-az-gti.html

[Elp]

25 minutes ago, a6400 said:

But then it will be attached by 1 screw and might be unsafe as you said. Any other idea what I could try?

 

The lens collar you've linked to has more than one fixing hole. Have you actually got it in hand?

There isn't really an issue mounting via the bottom of the camera body, i've sometimes done it with my adapted Canon Samyang 135s and they weigh a ton.

[a6400]

9 minutes ago, Elp said:

The lens collar you've linked to has more than one fixing hole. Have you actually got it in hand?

There isn't really an issue mounting via the bottom of the camera body, i've sometimes done it with my adapted Canon Samyang 135s and they weigh a ton.

Yeah but you would need dovetail with holes in same spot as collar and same size right?

 

Can’t mount camera directly to dovetail because of the lens design it’s too beefy.

[Elp]

Usually as long as the lens mounting hole isn't larger than 1/4 inch or M5/M6 maybe, a bolt will go through the dovetail slot, I use cap head screws because you can tighten them from the top of the bolt with an allen key.

You can mount the body to the dovetail, likely you'd need two dovetails to lift the body up to accommodate the lens (or riser blocks, aluminium blanks work well), or mount the body closer to the front of the dovetail for the lens to clear the dovetail.

There are many ways to approach mounting cameras, I've chopped and changed many times until I've reached a solution I'm happy with, as I setup fresh every time, usually using different lenses and cameras too so each situation calls for a different solution.

Cheese plates give you a multitude of camera mounting options as an alternative, but you'll still need to mount such to a vixen dovetail so it can be clamped into the mounts saddle.

Edited January 29 by Elp

[a6400]

Got the Neewer dovetail plate but the issue is with the second screw.

https://i.imgur.com/WMZQR9q.jpeg

The smaller 3/8" screw won't fit next to the larger one due to too large head.

Not sure how to look for a screw with same thread but smaller head?

Edited January 31 by a6400

[Elp]

There's three holes on that lens ring holder. What sizes are they? What is the depth measurement under the dovetail from the raised edge to the bottom face?

Cap head screws work well. Otherwise you can grind the outer circumference of your existing dslr screws smaller if you have access to power tooling and fit with a second smaller bolt/screw next to the first.

[a6400]

On 31/01/2024 at 21:25, Elp said:

There's three holes on that lens ring holder. What sizes are they? What is the depth measurement under the dovetail from the raised edge to the bottom face?

Cap head screws work well. Otherwise you can grind the outer circumference of your existing dslr screws smaller if you have access to power tooling and fit with a second smaller bolt/screw next to the first.

I will leave it at one screw, seems more than enough.

Thanks