Loose Skywatcher FF thread

[RayD]

I have recently taken delivery of my SW Esprit 80 with the matching SW field flattener.  When putting it together and checking the alignment, I notice the FF seemed my looser on the focus tube than I would expect from a relatively large and fine thread.

I took a few videos but they're too big to upload here, so below is my Dropbox link to them, and I would welcome your thoughts on whether you think I would have a good argument for insisting on a replacement, or whether you think this amount of movement isn't going to cause any issues.  As a note, when my EFW2 and camera are attached, and the FF isn't locked off, I can raise and lower the end of the camera by about 4-5mm.  When locking off the FF can differ in height by about 1-2mm in a vertical plane.

https://www.dropbox.com/sh/zftkhyh2og62rfh/AACx2cgrUrIXrKKRme2jyv0Ha?dl=0

[Peter Drew]

Fits of mass produced items can vary a little but from your descrption I would say that this is excessive. For photography a good fit for squareness and concentricity is usually essential. Do any other components fit correctly at this point?, this could define that it's the FF that is at fault.

[RayD]

Yes the screwed end cap that came off the focus tube to enable the FF to go on is spot on, so it would appear it is the FF for sure.

[laudropb]

That amount of movement is excessive. If you have purchased it new I would contact the retailer to ask for a replacement.

[RayD]

Yes was brand new from a very reputable UK supplier and they are waiting to hear back from SW to make a decision.  I just wondered what people's thoughts were on whether perhaps I was being a bit critical, or am right in thinking it should't be this 'sloppy".

Thanks for the feedback.

[cosmojaydee]

I have just purchased the same 2 items, having just checked mine , it has the same movement, not sure this is the norm but I will contact the supplier tomorrow for advice 

[RayD]

2 minutes ago, cosmojaydee said:

I have just purchased the same 2 items, having just checked mine , it has the same movement, not sure this is the norm but I will contact the supplier tomorrow for advice 

It just seems to me it would be difficult to get consistency for AP given how much it affects alignment.  I was checking some flats with CCD Inspector and the reference centre was moving all over the shop.  Shame as the rest of it seems excellent.

[cosmojaydee]

Ray , would you mind if I used you video's to send to a supplier ?

[RayD]

7 hours ago, cosmojaydee said:

Ray , would you mind if I used you video's to send to a supplier ?

No of course not if they are of help and demonstrate what you have also then feel free.

[RayD]

Just heard back from my supplier and they said SW has confirmed this is not right, and are going to replace either the connecting ring, FF or both depending what turns out to be at fault.  If you have the same cosmojaydee I suspect they may have had a run of bad rings.

[cosmojaydee]

5 minutes ago, RayD said:

Just heard back from my supplier and they said SW has confirmed this is not right, and are going to replace either the connecting ring, FF or both depending what turns out to be at fault.  If you have the same cosmojaydee I suspect they may have had a run of bad rings.

looking at it , it does seem to be a fault with the adapter rather than the FF

[RayD]

Just now, cosmojaydee said:

looking at it , it does seem to be a fault with the adapter rather than the FF

Yes that's what I've noted to them, but I guess to make sure they want both parts back.  I'm happy to do that as I don't want this as a potential weak spot on what is otherwise a pretty good OTA 

[cosmojaydee]

I have sent an Email to the supplier but as yet not heard anything 

[Nova2000]

Just for my knowledge what's ff? 

[cosmojaydee]

Its an abbreviation for Field Flattener  

[Nova2000]

The esprit refractor requires a ff? Isn't it mentioned on the skywatcher page that they have internal flatters? 

[glowjet]

Looking at the videos, there seems to be an excessive amount of play in the threads, as if one or the other has been cut oversize. certainly not any good in any shape or form for you guys involved in AP. Quite correct to return the goods, as it will be a matter for the supplier to sort out with SW, make sure you get covered for return postage costs.

Shame this happens when you take delivery of new goods, as the Esprit 80 seems to be an excellent all round refractor, hope you get things sorted

[cosmojaydee]

6 minutes ago, Nova2000 said:

The esprit refractor requires a ff? Isn't it mentioned on the skywatcher page that they have internal flatters? 

They dont have an internal FF 

 

5 minutes ago, glowjet said:

Looking at the videos, there seems to be an excessive amount of play in the threads, as if one or the other has been cut oversize. certainly not any good in any shape or form for you guys involved in AP. Quite correct to return the goods, as it will be a matter for the supplier to sort out with SW, make sure you get covered for return postage costs.

Shame this happens when you take delivery of new goods, as the Esprit 80 seems to be an excellent all round refractor, hope you get things sorted

Not what is stated on their homepage and I quote  Connect the triplet and doublet field flattener with a high precision thin thread to keep the optical axis perpendicular to the image.

[glowjet]

15 minutes ago, cosmojaydee said:

They dont have an internal FF 

 

Not what is stated on their homepage and I quote  Connect the triplet and doublet field flattener with a high precision thin thread to keep the optical axis perpendicular to the image.

So much for their quality production control, these things should not happen, but unfortunately they do and you end up being one of the unlucky customers to draw the short straw as it were

[cosmojaydee]

5 minutes ago, glowjet said:

So much for their quality production control, these things should not happen, but unfortunately they do and you end up being one of the unlucky customers to draw the short straw as it were

Yeah I agree, but I am aware of issues with mass produced products , but I would like to make it clear for anyone looking to buy an Esprit , this is an issue with the corrector adapter it seems,not with the OTA per se , hopefully my supplier will be in touch very soon as I have sent a few emails without response as yet 

[RayD]

10 minutes ago, glowjet said:

So much for their quality production control, these things should not happen, but unfortunately they do and you end up being one of the unlucky customers to draw the short straw as it were

I suspect the adaptor is made en mass in China or similar, so I guess at some point someone is likely to get a dodgy one, or as seems to be the case here, couple.  The actual FF seems absolutely fine, as does the focus tube, but this adaptor ring doesn't even "feel" like its of particularly good quality to be fair.