T2 to canon EF adapter

[TiffsAndAstro]

I think my camera has slight back focus (sensor slightly too close) and a little tilt.

I notice that when connected up to my scope, I can turn/rotate the dslr around the long axis of the scope a small amount, less than a mm, almost nothing. But still something. Between camera mount side of t2 adapter and where it connects to the dslr body.

Could either or both of the above issues  be related to the possibly lower quality T2 adapter?

Could the slight rotation and back focus be possibly fixed by one or more eg 0.1mm shim/rings between camera body and T2 adapter?

[michael8554]

I've had premium T2 adapters that have that slight rotation against the locking pin on the body.

And cheapest Chinese adapter that was perfect.

Luck of the draw on manufacturing tolerances.

Won't cause Tilt unless the bayonet is poor too.

And shims won't cure either.

You could try filling the index hole with solder, and redrilling slightly larger than the pin diameter.

Michael

[TiffsAndAstro]

On 05/05/2024 at 08:35, michael8554 said:

I've had premium T2 adapters that have that slight rotation against the locking pin on the body.

And cheapest Chinese adapter that was perfect.

Luck of the draw on manufacturing tolerances.

Won't cause Tilt unless the bayonet is poor too.

And shims won't cure either.

You could try filling the index hole with solder, and redrilling slightly larger than the pin diameter.

Michael

cheers for your reply, saves me trouble of trying random ones. ill worry about improving other areas instead 

[TiffsAndAstro]

So I've decided I've invented (manual) rotational dithering.

I'm sure Hubble and jwst will implement it soon.

I'll reach out to zwo see if they'd like to send me an astro camera to test against

[michael8554]

Dithering is intentional movement between images.

You don't want any movement during imaging.

Michael

[TiffsAndAstro]

4 hours ago, michael8554 said:

Dithering is intentional movement between images.

You don't want any movement during imaging.

Michael

I sort of meant I could rotate camera tiny amount, take a pic, rotate it back that same fixed amount, take a pic and repeat.

Only as a joke though