ASI 2600 Pro Duo and a Canon EF lens

mikemilton

How do I do this?

The promo and manual info shows the EOS T2 adapter attached directly to the camera as if it has 54mm threads but it does not.

I tried replacing the back of the adapter with an ASI 54mm filter drawer but it is slightly too long (and won’t focus to infinity)

It might be possible to adapt the T2 thread to 54 mm but that would cover at least some of the guide sensor.

Is there another spacer from the adapter to the camera?

Clearly people have done this - HOW???

w7ay

mikemilton Clearly people have done this - HOW???

Just get the "New" EOS filter drawer:

https://astronomy-imaging-camera.com/product/new-filter-drawer-for-eos-lens/

(Be sure to throw away any old ZWO filter drawers, since they leak light as a sieve, and cannot be used for astrophotography other than at really dark sites; the "new" GEN2 have the filter holder countersunk into the drawer.)

The EOS adapter comes with an M42 to M54 ring to intefrace with ZWO's M54 "tilt plates" for their cameras. Thread the ring over the male M42 of the drawer, and it looks like a M54 male interface, but with the M42's opening.

Done.

I don't know if ZWO now sells an EOS adapter with an M54 interface. The M42 filter will badly vignette a full frame camera (the clear opening of the M42 interface in the drawer is 38mm), but should work with the small sensor (28mm diagonal) on your ASI2600.

If you want a M54 interface, get the "New" EOS filter drawer. Then get the GEN 2 stand-alone filter drawer with M54 interface (ZWO also makes one for M42 interface, so be sure to buy the right one). Replace the M42 (T2) back from the EOS adapter (just a couple of screws) by the back from the standalone M54 filter drawer.

Photo shows the modified "new" EOS adapter at the back of a Rokinon 135/T2.2 lens with EOS interface. You can just see a small sliver of the shiny Rokinon flange.

Notice that I have to add a thin shim (the stainless steel washer) to the drawer to compensate for the len's backfocus when filter glass is added to the optical path. ZWO produces filter drawers and filter wheels, but assume you do not place any filter in them!!! With ZWO's drawers, you need to add a shim that is 1/3 the thickness of the filter glass. Filters such as the Radian Quad, Chroma and Astrodon are 3mm thick, and contribues 1mm to the backfocs. Caveat Emptor.

https://cloudbreakoptics.com/products/new-filter-drawer-for-eos-lens
https://cloudbreakoptics.com/products/new-2-filter-drawer?variant=43595031871737
https://agenaastro.com/blue-fireball-9-pc-fine-tuning-spacer-ring-set-for-m54-threads-0-1-to-1-0-mm-s-set9.html

Again, be sure it is all GEN2 ("new") products. You cannot mix and match new and old ZWO drawers. Notice the shape of the filter holder -- different from the older (there were two generations actually, that preceeded what is generally called the GEN2 drawers; both of the old ones leak light). Only the "new" or "GEN2" drawers/filter holders have the holder countersunk and flush with the drawer's cylinder.

Yes, you have to replace all of your old filter holders too -- they do not work with the new filter drawers. I guess this is how ZWO makes money -- make you buy everything twice or three times (in the case of filter drawers). If they change again, I will switch to Antlia's universal filter drawer system, which appears to be a much better thought out design.

https://www.cloudynights.com/topic/779676-antlia-filter-drawer-system/

Chen

Tech@ZWO

mikemilton We will release the accessories that change the thread on the adapter to M54 soon

mikemilton

Thanks - I’ll give that a try

mapa

Tech@ZWO Any update on version with M54 on both sides ?

MalcolmPark

has the 54mm threaded version been made available? What do we use to connect a canon lens to the camera, with no filter wheel and no filter drawer? M42 threads cut off the guide chip. How do we connect at m54 so as not to cut off the guide chip?

Tech@ZWO

MalcolmPark Should be released soon, let me confirm the estimated date with our team.

nhmorgan

It's the end of November and I was super excited to have my new ASI2600MC Air arrive only to discover this same problem. I can't use it with lenses because the only adapter covers the guide sensor. I bought this to be a portable lens-based DSLR replacement, but no go. Every alternate I can find removes the ability to use the camera with filters.