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Re: EOS Lens Adapter Loose - EFW Version

Posted: Fri Jun 01, 2018 3:21 pm
by another_mikey
Sean,

That sounds good. Yes, I cannot get this to work on any of my 3 Canon lenses that I own.

I did not buy this from a dealer but bought this adapter direct from ZWO. Is there a way to get another one before my trip on June 10th? Please advise on quickest way for me to make this happen. I would still very much like to have this before I leave if it is at all possible. And as stated, I can return ship the one I have back to you as well if you give me instructions to do so.

Thank you,

Mike Lewis
57507 Gunbarrel Road
Longmont, CO 80503
USA
303-834-2937

Re: EOS Lens Adapter Loose - EFW Version

Posted: Mon Jun 04, 2018 12:53 am
by Sean.Wang
Yes, please send us your address to support(at)zwoptical.com. We will send them as soon as we can. Also we will give you a address to send the old adapter back to us. two of them.

Re: EOS Lens Adapter Loose - EFW Version

Posted: Fri Sep 07, 2018 12:01 pm
by bellavia
Hi,

I too own a ZWO-EFW-EOS, and it has a tremendous amount of play in it. I measured the gap to be 0.3mm

Is there a spacer to tighten this up, or can I get the newer version, that supposedly is tighter? It is loose on all my lenses (at least 6 of them), causing tilt, and thus stars get elongated from one side to another.

Thank you!

Steven Bellavia

Re: EOS Lens Adapter Loose - EFW Version

Posted: Thu Sep 27, 2018 3:58 am
by Sean.Wang
Please take a look of previous post, I told one way to make adapter tighter.

Re: EOS Lens Adapter Loose - EFW Version

Posted: Thu Sep 27, 2018 7:09 am
by Konihlav
best way to make it tight is to buy a EOS lens adapter that has a contra-screw-tightening nut like the adapter from Geoptik (but it also isn't super perfect as the nut is kind small and has only little of travel, but it's the best (so far) commercially available product - BECAUSE it has NOT PLAY at all!!!).

I wonder why all other makers base the adapter on the same stupid one little spring side-lock... for astronomy this will never work (unless you do not care about star shape which is the case that many people have also damaged lens that can't be ever focused in all 4 corners at all so they do not care because they do not see it)...

Re: EOS Lens Adapter Loose - EFW Version

Posted: Sat Sep 29, 2018 2:44 pm
by Sean.Wang
Konihlav wrote:best way to make it tight is to buy a EOS lens adapter that has a contra-screw-tightening nut like the adapter from Geoptik (but it also isn't super perfect as the nut is kind small and has only little of travel, but it's the best (so far) commercially available product - BECAUSE it has NOT PLAY at all!!!).

I wonder why all other makers base the adapter on the same stupid one little spring side-lock... for astronomy this will never work (unless you do not care about star shape which is the case that many people have also damaged lens that can't be ever focused in all 4 corners at all so they do not care because they do not see it)...
We found that EOS lens are quite different, some will be loose, some will be very tight. so we made 3-4 modify but still didn't fit all EOS lens.

Re: EOS Lens Adapter Loose - EFW Version

Posted: Fri Oct 05, 2018 2:22 am
by James_Sorenson
20181004184025_IMG_4235.JPG
I bought my adapter at the end of feburary, it has play issues as well. I can't seem to get good stars in my images because of lens flex with my Rokinon 135 f2. It is supported with a ring. I want to know if the one that I have is the old model or the newer one? It seems the one I have has very thin locking flange tabs and judging by the pics posted here, they are thicker. I also question the flatness on mine.

Re: EOS Lens Adapter Loose - EFW Version

Posted: Fri Oct 05, 2018 2:49 am
by James_Sorenson
Konihlav wrote:best way to make it tight is to buy a EOS lens adapter that has a contra-screw-tightening nut like the adapter from Geoptik (but it also isn't super perfect as the nut is kind small and has only little of travel, but it's the best (so far) commercially available product - BECAUSE it has NOT PLAY at all!!!).

I wonder why all other makers base the adapter on the same stupid one little spring side-lock... for astronomy this will never work (unless you do not care about star shape which is the case that many people have also damaged lens that can't be ever focused in all 4 corners at all so they do not care because they do not see it)...
I have considered getting a Geoptik to solve the whole problem but one issue exists that prevents me from doing that. It's to thick for my setup. I wish it was thinner...

Re: EOS Lens Adapter Loose - EFW Version

Posted: Sat Oct 06, 2018 11:07 pm
by bellavia
Sean.Wang wrote:Please take a look of previous post, I told one way to make adapter tighter.
I think I have taken care of it.

I purchased 0.0125 inch (0.32mm) polyester shim stock and cut it into a washer, with a small hole in it.

https://www.mcmaster.com/9513k21

That seems to have removed most or all of the slop and it is not too tight either.

See attached images.

Re: EOS Lens Adapter Loose - EFW Version

Posted: Tue Oct 09, 2018 1:52 am
by James_Sorenson
Looks like you have the same one as I do. I have tried spacing with shims several times and varified that I have the correct total spacing for everything. Can't seem to get rid of the lens tilt in my images.