How do you connect the William Optics Z61 + WO 61A + ZWO ASI533MC Pro

[KEJ]

Hi

Can I please ask, is there anyone out there with the following or a similar setup to this:
 

• William Optics Z61 Scope + WO 61A Flattener + ZWO ASI533MC Pro (or other ZWO Camera) ?

 

Currently,  I have been using the following setup:

• William Optics Z61 Scope + WO 61A Flattener + Nikon DSLR
   

However, by the end of the week I am hoping to have this new setup:

• William Optics Z61 Scope + WO 61A Flattener + ZWO ASI533MC Pro
   

I was really just wondering how the more experienced out there had configured/connected their equipment together?

How people connect their ZWO cameras to the flatteners?

Are the flatteners still required with the smaller sensor cameras ?

I was just wondering if anyone has any pictures of similar setups to above please (equipment trains)?

 

Thanks in advance for any comments or advice.

Edited October 5, 2020 by KEJ
Improved title

[symmetal]

Hi KEJ, I have a ZS61 + Flat 61A + ASI071MC.

The back focus distance from the flattener rear to the camera sensor is 67.7mm as shown below for the ZS61 scope.

This is with the adjustment ring set to zero on the flattener. A DSLR and T-adapter has a standard back focus distance of 55mm so to achieve 67.7mm you can set the adjustment ring on the flattener adjuster to add the difference of 12.7mm as shown below. This shows 12.9 instead of 12.7 but it's close enough.

The flattener rear thread is M48 so I used an M48 extender followed by a M48 to M42 adapter to screw on to the camera. Using M48 for most of the distance reduced any possible vignetting that may occur. The 533 back focus is 6.5mm so you want a total spacing of 61.2mm. You have up to 15mm of adjustment on the flattener so the extension spacing needs to be between 61.2 and 46.2mm with any shortfall below 61.2 made up on the flattener adjustment.

With the flattener adjustment ring fully removed you can insert a 2" filter in the rear of the flattener if you wish though the filter will reduce the adjustment range by the thickness of the filter. With a UV/IR cut filter in mine the adjustment range is from about 7mm to 15mm. Filters can be added as part of the M48 to M42 extension if preferred as indicated in the camera manual. There are a number of extensions and adapters with the camera which will work but as I preferred M48 for as far as possible I bought a separate 30mm M48 extender from FLO.

Alan 

[KEJ]

Alan good morning

Brilliant and thank you, once the camera arrives I will have a setup session in the kitchen.

I believe the camera comes with several connectors and initially the shop advised I could use a 1.25 IR filter in the 1.25 adapter connector which would fit into WO female(which I currently don't use).

I will add some pictures later to show what I mean, but thank you for the info.......watch this space.

Cheers

Keith 

[KEJ]

Alan

Right,  run and breakfast out of the way, not good when it's raining especially.

I just popped into the kitchen and disconnected my DSLR and added on the William Optics (WO) 1.25" adapter instead, so I assume and would you agree, that potentially this would be a setup that should work(possibly tweaks for back focus).

 

Equipment Train

WO Z61 Scope + WO 61A Flattener + WO 1.25” Adapter(female)  + *(ZWO 1.25” T-Mount(male) with 1.25” IR Filter fitted + ZWO ASI533MC Pro camera)*

*(New equipment on order)

 

As shown below, minus the new equipment

Thanks

 

 

 

Edited October 6, 2020 by KEJ

[KEJ]

******

Update

******

I did just query this with the Retailer and now, they said they would recommend 2" IR filter instead.

And do away with the 1.25" filter and adapters, which was in the back of my mind and my reason for also firing off the above to them this morning.

Hopefully now sorted out and before the order is dispatched.

[KEJ]

Alan

Yes, that now all makes sense - thank you.

I will attempt to add the 2" filter to/inside the flattener and then check out your numbers.

 

Brilliant and thanks

[Adam J]

7 hours ago, KEJ said:

Alan good morning

Brilliant and thank you, once the camera arrives I will have a setup session in the kitchen.

I believe the camera comes with several connectors and initially the shop advised I could use a 1.25 IR filter in the 1.25 adapter connector which would fit into WO female(which I currently don't use).

I will add some pictures later to show what I mean, but thank you for the info.......watch this space.

Cheers

Keith 

Yes an IR cut will probably be required so as to prevent bloated stars. You will find an adaptor to allow you to use 1.25 inch filters with the camera in its box.

I really dont see why you would go with a 2 inch filter for this camera??? Its such a small sensor there is no need. 

I know its not a ASI533mc pro but they all have the adaptor included and all work in the same way. In the case of the pro you just thread it onto the black female to female extension on the front of the camera. 

I would just save yourself money and buy smaller cheaper filters. 

In addition to that all the T2 extenders you will need to connect to the scope are in the camera box. The only thing you should need in addition to what comes with the camera is the IR cut filter. 

Adam

Edited October 6, 2020 by Adam J

[KEJ]

Adam hi

Bo*****s!     My order has been dispatched, I didn't realise that.

And thank you........I can have a look when it all arrives.............

Also, whilst being slightly annoyed, I won't mind too much if I can actually us the 2 inch filter.

 

 

Edited October 6, 2020 by KEJ

[symmetal]

Hi KEJ, As Adam says your sensor is quite a bit smaller than my APS-C size 071 camera so the 2" filter size is not a necessity, neither is prioritizing M48 extensions. I should have mentioned this in your instance but at least your system is future proofed against a bigger camera if you get one. 🙂

As you've now done, it's best not to use the 1.25" eyepiece adapter in the imaging train but to screw everything together so that the camera is held in a fixed orientation to the flattener and reduces any chances of any tilt happening.

Your first post asked if the FF was actually necessary. As you have it you may as well use it. The corner stars may be good enough without it, but using it should make them better. 🙂

Alan

[KEJ]

Thank you all.

All the gear finally arrived, I removed my DSLR, added the 2" IR filter into the 61A flattener, used two spacers and connected the camera ASI533.

Kept the focus position to what I used for my DSLR camera on the WO Z61 scope, cooler connected up and working, piggy backed my ASI120MC-S into the 533 and Bingo all working.

 

The only thing I want to check are the measurements that Alan gave me above tomorrow, I might have hit the numbers exactly by accident & got them spot on.

Regarding cooling, is there a procedure you should follow or is that BS to avoid thermal shock to the sensor?

Example

Before a nights shoot, 10 mins before set the temperature to zero on the camera, 5 mins before down to your desired temperature -10.....

take all of your pictures

Then the reverse........set camera to zero and leave for 10 mins before turning off etc or discounting the fan.

 

What do you chaps do ?

Cheers

 

[geeklee]

1 hour ago, KEJ said:

Before a nights shoot, 10 mins before set the temperature to zero on the camera, 5 mins before down to your desired temperature -10.....

take all of your pictures

Then the reverse........set camera to zero and leave for 10 mins before turning off etc or discounting the fan.

I think most programs (certainly Apt and Voyager) cool the camera down at a sensible rate (with varying parameters of your choice to help speed up or slow down).

For heating, they have "warm up" type functions that, as far as I can see, just reduce the cooling power slowly so it comes up to temperature over 5 minutes or so.  You can tell the difference Vs turning the cooler off immediately - it heats back up quick!

Depends on timing for how you set up to when you kick the process off.  It can obviously just sit there at -10 (or whatever) for a good time before you start shooting  (if required).

Meant to say, one of my cameras is the ASI533! It's been through plenty of cycles and being cooled for 8-9 hours at a time (for example) and had a few accidental quick warm ups when I've had a software failure.

Hope this helps.

Edited October 7, 2020 by geeklee

[symmetal]

As geeklee says re the cooling. I use SGP and set it to cool down or up to specified temp in 10 mins but that's just habit.

Concerning the FF spacing remember to add extra distance to the 67.7mm specified due to the filter and protective glass in the light path as refraction through them moves the actual focus point back by around 1/3 the thickness of the glass. So you FF spacing should be nearer 69mm. As your sensor is not large though, the spacing shouldn't be that critical in your case.

Alan

[Adam J]

16 hours ago, KEJ said:

Thank you all.

All the gear finally arrived, I removed my DSLR, added the 2" IR filter into the 61A flattener, used two spacers and connected the camera ASI533.

Kept the focus position to what I used for my DSLR camera on the WO Z61 scope, cooler connected up and working, piggy backed my ASI120MC-S into the 533 and Bingo all working.

 

The only thing I want to check are the measurements that Alan gave me above tomorrow, I might have hit the numbers exactly by accident & got them spot on.

Regarding cooling, is there a procedure you should follow or is that BS to avoid thermal shock to the sensor?

Example

Before a nights shoot, 10 mins before set the temperature to zero on the camera, 5 mins before down to your desired temperature -10.....

take all of your pictures

Then the reverse........set camera to zero and leave for 10 mins before turning off etc or discounting the fan.

 

What do you chaps do ?

Cheers

Honestly, I am not 100% sure warm up is a big issue with CMOS as the number of times I have disconnected the camera by mistake (equivalent to pulling the power) is not insignificant. So while i would not do it as a matter of course I dont view its a critical either. 

Adam

[KEJ]

On 05/10/2020 at 20:00, symmetal said:

Hi KEJ, I have a ZS61 + Flat 61A + ASI071MC.

The back focus distance from the flattener rear to the camera sensor is 67.7mm as shown below for the ZS61 scope.

This is with the adjustment ring set to zero on the flattener. A DSLR and T-adapter has a standard back focus distance of 55mm so to achieve 67.7mm you can set the adjustment ring on the flattener adjuster to add the difference of 12.7mm as shown below. This shows 12.9 instead of 12.7 but it's close enough.

The flattener rear thread is M48 so I used an M48 extender followed by a M48 to M42 adapter to screw on to the camera. Using M48 for most of the distance reduced any possible vignetting that may occur. The 533 back focus is 6.5mm so you want a total spacing of 61.2mm. You have up to 15mm of adjustment on the flattener so the extension spacing needs to be between 61.2 and 46.2mm with any shortfall below 61.2 made up on the flattener adjustment.

With the flattener adjustment ring fully removed you can insert a 2" filter in the rear of the flattener if you wish though the filter will reduce the adjustment range by the thickness of the filter. With a UV/IR cut filter in mine the adjustment range is from about 7mm to 15mm. Filters can be added as part of the M48 to M42 extension if preferred as indicated in the camera manual. There are a number of extensions and adapters with the camera which will work but as I preferred M48 for as far as possible I bought a separate 30mm M48 extender from FLO.

Alan 

Alan hi

Once again thank you for the attached.

So just going off your measurements(I still haven't looked on the website yet).

I have now set it as per my attached drawing.

As suggested I connected the 2" IR filter inside the flattener and then put the hood back on over up to the 11.2mm mark.

I then added 2 of the spacers that came with the camera to make a total distance between the flat surface of the camera and flattener hood of approx 50mm.

 

In theory 11.2mm + 50mm = 61.2mm

However, that is my measurement to the outer camera case??

I will give it a try now and then also have a look online.

 

Thanks

 

*** Update saw your second message ***

So I have now changed the 11.2mm below(in diagram) back to 12.5mm...................originally I had it set to 12.9mm for my Nikon Camera.

Revised:

Now, in theory 12.5mm + 50mm = 62.5 mm

 

Edited October 8, 2020 by KEJ
amended text after second message

[KEJ]

4 hours ago, Adam J said:

Honestly, I am not 100% sure warm up is a big issue with CMOS as the number of times I have disconnected the camera by mistake (equivalent to pulling the power) is not insignificant. So while i would not do it as a matter of course I dont view its a critical either. 

Adam

Adam

Ok, thanks.............just me not knowing, so I would rather ask.

 

Cheers

[symmetal]

Hi KEJ,

Yes, your drawing is correct with the updated increase on the flattener adjustment from 11.2 to around 12.9mm to account for the extra glass in the way. The front glass and the filter are 2mm thick I believe, so adding 1.3mm for the total glass would in theory be correct making a setting of 12.5mm on the FF the more theoretically correct figure.

However, the sensor size on the 533 is not large, so FF spacing is not so critical, and I doubt whether 0.4mm would make any actual difference to the image results. It's a coincidence the spacers you've used actually make your 533 setup almost the same as a DSLR. 🙂

In practice, with large sensors, you almost always have to make slight fine adjustments to the FF spacing to get the optimum results, as some of the figures quoted for camera back focus etc. may be slightly different from the published figure.

Alan

[KEJ]

31 minutes ago, symmetal said:

Hi KEJ,

Yes, your drawing is correct with the updated increase on the flattener adjustment from 11.2 to around 12.9mm to account for the extra glass in the way. The front glass and the filter are 2mm thick I believe, so adding 1.3mm for the total glass would in theory be correct making a setting of 12.5mm on the FF the more theoretically correct figure.

However, the sensor size on the 533 is not large, so FF spacing is not so critical, and I doubt whether 0.4mm would make any actual difference to the image results. It's a coincidence the spacers you've used actually make your 533 setup almost the same as a DSLR. 🙂

In practice, with large sensors, you almost always have to make slight fine adjustments to the FF spacing to get the optimum results, as some of the figures quoted for camera back focus etc. may be slightly different from the published figure.

Alan

Alan

Brilliant thank you.

I just took a test shot over the valley(only manual focus from the inside the house/kitchen) and it looks clear enough.

How do I know(stupid question maybe) that I don't have the optimal settings or basically is it clear, then you are fine ?

 

Just checked the website:

For my camera 55mm back focus, then using your diagram (always confused with the 2 two columns A/B) 67.7 required.

 

Is this correct please

50mm of spacers + 12.5mm adjusted on flattener + 6.5mm sensor seated = 69mm. (allowing for extra glass?)

Is that because from the last glass, that is where the measurement is taken ?

 

On their website is states back focus distance 6.5mm/17.mm is that to give you room to play/focus or anywhere there will be fine ?

 

Thanks in advance for your help

 

 

Edited October 8, 2020 by KEJ

[symmetal]

Hi KEJ,

You'll only see if the spacing is correct with actual star images. You examine the corner stars in a test image to see if they are nice and round and not distorted into elongated stars (or little seagulls sometimes). The further you are from the centre of the image the worse the distortion becomes, which is why large sensors show it more, and make the spacing distance more critical.

The 55mm backfocus distance is a standard figure for DSLRs.

It's confusing that backfocus has a different meaning depending on what's being discussed.

For a lens, the backfocus is the distance from the centre of the rear lens element(s) to the image focal plane (the camera sensor). As this is not easy to measure in practice, a figure from the rear of the lens casing is quoted instead, which is easier to measure in use. This is the 67.7mm distance quoted on the WO diagram, (if the adjustable section is set to zero). The 69.2mm figure is I believe from an internal M54 thread which is accessed by removing the adjustable section of the flattener which ends in the M42 thread. Using the M54 thread there is no adjustable feature on the flattener. 

For a camera, the backfocus is the distance from the front lens attachment point of the camera to the image sensor. For a DSLR this is usually 55mm. For your 533 it's only 7.5mm, which is why you need extra spacers to make up the distance to achieve the total FF backfocus ( FF spacing), when using astro cameras instead of DSLRs.

40 minutes ago, KEJ said:

Is this correct please

50mm of spacers + 12.5mm adjusted on flattener + 6.5mm sensor seated = 69mm. (allowing for extra glass?)

Yes. 😀

Alan

Edited October 8, 2020 by symmetal

[KEJ]

Thank you - just outside now.

I fired off 50 mins at the veil and now just having a quick go at M33 before bed, more of test really.

All seems to be working, only saving to the memory stick and viewing on the iPad and stacking in the app.

I will stack properly on the laptop tomorrow.

Gain 101 and 5min exp on the veil and 3 mins on M33 before the Moon appears(any minute).

Thanks again for your help and everyone else.

Edited October 8, 2020 by KEJ

[alexander85]

Hi all,

I'm a first time poster and attempting to make my first steps in astrophotography. I have the exact same setup as quoted below:

Quote

Currently,  I have been using the following setup:

• William Optics Z61 Scope + WO 61A Flattener + Nikon DSLR

However, I'm completely unable to achieve focus. With my flattener set to 12.7mm as described above (to obtain 67.7mm), it's as if the camera is set too far back so that even with the scope focusser fully inserted (as far forward as possible), the image is completely blurred. As I retract the scope focusser, the image just gets more and more blurred. I've taken some pictures without the flattener, and with the flattener set to 0mm, and have no focusing issues, but of course I lose the benefit of the flattener in that case. The maximum I can set the flattener to and still focus the scope is around 5-6mm.

I'm trying to determine if there's an issue with my kit or if I've overlooked something.

Thanks for any help you can give!

Alexander

[symmetal]

Hi Alexander,

Most odd. Can you post a picture of a side on view of your setup showing the scope, flattener, camera adapter and camera.

What model Nikon camera do you have? As you said it's a DSLR I assume you have the correct Nikon-M48 adapter fitted to your camera to allow it to screw onto the rear of the flattener. Unlikely to be wrong as there are only F-mount or Z mount I believe, with the Z-mount being much longer due to it being for mirrorless cameras and also a different lens flange diameter.

Also is the flattener screwed directly onto the M54 thread on the rear of the scope. You have to unscrew the the scope's 2" eyepiece fitting first.

Alan