EOS Lens Adapter Loose - EFW Version

another_mikey

When I have any of my Canon lenses mounted to my ASI1600MM-C camera I have a fair amount of play (looseness, lens turns after engagagement, along with wobble). I have the last version of the camera prior to the release of the Pro series, if that matters. I see this behavior with any of my Canon lenses mounted. I do use a lens mounting ring for my larger lens, along with the camera mounting ring. I had a custom spacer plate made (about 8mm for mounting my Canon 70-300 f/4-5.6 L IS lens) that tries to take the elevation difference between the 2 plates into account.

This problem is obvious even when mounting a lighter lens, and just holding the camera completely vertical. The lens still turns a noticeable amount back and forth when clicked into place and also has significant side wobble as well.

As a result of all of this, my attempts to image using this adapter so far have resulted in inconsistent star quality across the frame, often shifting during the imaging session as the camera rotates through different orientations.

I bought this adapter back when I got my camera, a while ago. I did see elsewhere in this Accessories forum a mention from ZWO that this adapter has been improved - is that true? I would try a newer version if there is some reason to believe the design has been improved to mitigate or eliminate these issues. Can anyone from ZWO confirm this?

Thanks bunches,

Happy ZWO ASI1600 Owner!

Mike L.

Longmont, CO, USA

Support@ZWO

Hi there.

Yes, The EOS adapter is much tight now.

another_mikey

Sean,

Ok thanks. Based on your comments, I have ordered a second EOS EFW compatible lens adapter, with the expectation that it sill not be loose like the 1st one. Additionally, I have also ordered the upgraded 78mm camera mounting ring as well. Thanks for the help. I will let you know if this does not seem to fix my problem.

Support@ZWO

You are welcome, ML. Have a good day!

another_mikey

Sean,

My shipment of my EOS EFW lens adapter and new mounting ring came in Friday, I just received them today as I was out on company travel Friday. Unfortunately the new EOS EFW lens adapter is now MUCH too tight. It is impossible to mate it to a lens now - it is so tight it can barely rotate at all and then gets so tight it is stuck and almost cannot me removed. It has no way to rotate far enough to let the pin engage.

I have now bought 2 of these, one is very loose and the new one is impossibly tight. I have checked on multiple lenses (which all mate perfectly to either of my 2 Canon DSLRs) and I have the same problem with this new adapter on all 3 of my lenses.

I noticed that the alignment dot on the new adapter is white instead of red - since it seems to align up initially I am thinking this cannot be the wrong type of adapter but thought I would check. I am going to very dark skies for a week of imaging with my ASI1600 starting 10 June. Is there any chance that someone can help me to understand and solve this problem and potentially send me a non-defective adapter before I have to leave? I don't feel good about having to potentially pay for a 3rd one of these, especially with the issues I have seen so far. I LOVE my camera and filter wheel, and ZWO service so far has been excellent. Hoping someone can help me out. If someone needs to contact me directly I can pass on my email (although probably captured under my user profile I think...)

Thanks for any assistance,

Mike L.

Longmont, CO USA

Support@ZWO

another_mikey wrote:
Sean,

My shipment of my EOS EFW lens adapter and new mounting ring came in Friday, I just received them today as I was out on company travel Friday. Unfortunately the new EOS EFW lens adapter is now MUCH too tight. It is impossible to mate it to a lens now - it is so tight it can barely rotate at all and then gets so tight it is stuck and almost cannot me removed. It has no way to rotate far enough to let the pin engage.

I have now bought 2 of these, one is very loose and the new one is impossibly tight. I have checked on multiple lenses (which all mate perfectly to either of my 2 Canon DSLRs) and I have the same problem with this new adapter on all 3 of my lenses.

I noticed that the alignment dot on the new adapter is white instead of red - since it seems to align up initially I am thinking this cannot be the wrong type of adapter but thought I would check. I am going to very dark skies for a week of imaging with my ASI1600 starting 10 June. Is there any chance that someone can help me to understand and solve this problem and potentially send me a non-defective adapter before I have to leave? I don't feel good about having to potentially pay for a 3rd one of these, especially with the issues I have seen so far. I LOVE my camera and filter wheel, and ZWO service so far has been excellent. Hoping someone can help me out. If someone needs to contact me directly I can pass on my email (although probably captured under my user profile I think...)

Thanks for any assistance,

Mike L.

Longmont, CO USA

Hi Mike

I'm sorry about this. I got a way maybe helpful to make it work.

another_mikey

It seems like the fit is currently so tight that it may be more than just the spring force, but I will try to see if I can flatten those springs out a little bit and see if that might help.

I will let you know how it goes.

another_mikey

Sean,

I looked again at my adapter. The springs are actual quite flat. In addition, the springs are not the issue because the adapter binds up well before the springs are even engaged by the lens. The difference I see between my 2 adapters that seems significant is that the flanges on the new adapter are significantly thicker than on the old adapter. Interestingly, the old adapter (which is loose when mated) already has the springs quite extended.

New adapter, camera side (camera thread adapter removed) showing spring very flat, this is super tight before spring even engages

NewAdapter_CameraSide.jpg

Old adapter, camera side (camera thread adapter removed) showing spring extended, this is still loose

OldAdapter_CameraSide.jpg

There is no way I can see that the new adapter could have ever worked. perhaps it has a manufacturing defect or tolerance issue?

Any way to get a good one sent out quick before my trip? I will gladly mail the defective new one back in exchange, but not enough time to wait for you to receive it. Even if you cannot send another before you get mine I would still like to exchange the new bad one, or at the very least get my money back, as it is completely unusable as is.

Thanks bunches,

another_mikey

Additional images from the lens side:

NewAdapter_LensSide.jpg

OldAdapter_LensSide.jpg

Support@ZWO

tolerance issue, new adapter is much tight than before, we tested with two Canon lens before sell them, but looks like some lens use that adpater still too much tight.

We can give you replacement. dealer will help you switch them.

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

Support@ZWO

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.

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

Support@ZWO

Please take a look of previous post, I told one way to make adapter tighter.

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)...

Support@ZWO

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.

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.

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...

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.

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.