Attach ZWO ASI 533MC Pro

[Hoopla]

Hi All,

im hoping someone can help. I have a skywatcher 150p explorer scope and in wanting to get better DSO shots I’ve purchased a ZWO ASI533MC Pro camera however I’m trying to attach the camera to the scope to gain focus and attempt to get used to the software during the day so that in the eve o can hopefully get a few shots going. 
 

I simply can’t seem to get any level of focus. I’m aware regards the gain and exposure and am sure it’s not that but more the spacers I’m using when attaching to my scope. 
 

i have tried so many combinations and the manual does not seem to line up with the wording on the spacers it’s self. Can anyone please help!!   I have attached the spacers I have in the pack. I’m sure I’m doing something stupid but just can’t seem to resolve this. 

[CraigT82]

What are you trying to focus on? It may be too close which would require a lot more outwards focuser travel?

[Hoopla]

Hi Craig, thank you for replying. I’m trying to focus on a tree a very long way off. 
 

all I’m seeing is green as I take it through the gain or exposure on the way to white or black (depending on which way the slide is going). 
 

im really unsure if the adapter I’m using are the correct ones for my scope? 

[Craney]

Later this afternoon the Moon should be rising in a (hopefully) blue sky..... it is looking promising here in N Yorks.

An easy target to find and is pretty much at 'infinity' for a telescope.   That should get a result for you. If not post a picture of your imaging set up and we might be able to spot something.

Sounds like you have the software working which is always a bonus.

Sean.

[discardedastro]

The way I sanity check my adapter configuration is to grab an eyepiece with a similar field of view and make a note (mentally or with some dry-wipe marker) of where the first lens in the bottom of the eyepiece is when viewed from the outside. Then, get that to focus. You now have a mark on the outside which is roughly where you need to place your focal plane. You can then simply hold up your adapters (or measure, etc) and see if you get the same answer, more or less! Then adjust to suit.

On Newts, often you'll surprise yourself with how far back you need the camera's sensor to be relative to where you might end up with an eyepiece "sitting" because of the offset between the actual entry pupil location (the first lens in the eyepiece towards the scope) versus the "stop" of the eyepiece in the barrel.

[Hoopla]

2 minutes ago, Craney said:

Later this afternoon the Moon should be rising in a (hopefully) blue sky..... it is looking promising here in N Yorks.

An easy target to find and is pretty much at 'infinity' for a telescope.   That should get a result for you. If not post a picture of your imaging set up and we might be able to spot something.

Sounds like you have the software working which is always a bonus.

Sean.

Thanks Sean, I’ll try this. I’m aware I could just be shooting too close but thought it would be able to focus initially on my target as my canon 700d does. 
 

I’ll give it a shot and try. 

[CraigT82]

Is your scope the PDS version? If not I'd think you'd need to use the least amount of adaptors necessary as the camera will focus almost all the way in? Can you focus normally on the tree using an ep? If so where abouts is the focus travel at focus then? You would want the camera sensor to be at roughly the same position as the field lens of the EP.

 

Edit: just seen that you can get focus on the tree with your dslr. I'd put the dslr in, focus on the tree then make a note of where in the focuser travel it is, then trying to replicate that with the ASI. Will need to take into account how far into the body each sensor is on the two cameras

Edited January 23, 2021 by CraigT82

[Hoopla]

2 minutes ago, discardedastro said:

The way I sanity check my adapter configuration is to grab an eyepiece with a similar field of view and make a note (mentally or with some dry-wipe marker) of where the first lens in the bottom of the eyepiece is when viewed from the outside. Then, get that to focus. You now have a mark on the outside which is roughly where you need to place your focal plane. You can then simply hold up your adapters (or measure, etc) and see if you get the same answer, more or less! Then adjust to suit.

On Newts, often you'll surprise yourself with how far back you need the camera's sensor to be relative to where you might end up with an eyepiece "sitting" because of the offset between the actual entry pupil location (the first lens in the eyepiece towards the scope) versus the "stop" of the eyepiece in the barrel.

Thank you. I’ll give that a shot too if I can’t get focus on the moon a bit later this afternoon. 
 

I have to say I’m pretty impressed with the forum. Never seems to disappoint. Thank you all. 

[Hoopla]

14 minutes ago, CraigT82 said:

Is your scope the PDS version? If not I'd think you'd need to use the least amount of adaptors necessary as the camera will focus almost all the way in? Can you focus normally on the tree using an ep? If so where abouts is the focus travel at focus then? You would want the camera sensor to be at roughly the same position as the field lens of the EP.

 

Edit: just seen that you can get focus on the tree with your dslr. I'd put the dslr in, focus on the tree then make a note of where in the focuser travel it is, then trying to replicate that with the ASI. Will need to take into account how far into the body each sensor is on the two cameras

If I can just ask Craig, which of the adaptors in the picture would you suggest using please? I can only seem to fit the bottom left adaptor in the image above directly to the camera but this won’t fit on the T2 u used with the canon to add length. 

[KP82]

The standard flange distance in a Canon DSLR is 44mm and with the T-ring 54 - 55mm. The CMOS sensor inside your ASI533MC is about 6.5mm into the camera body without the T2 adapter. Once you add the T2 adapter (top left), the distance becomes 17.5mm. If you add the 21mm T2 extension you have there, that will make it 38.5mm. So in order to reach focus, you will need to move the drawtube another 16mm-ish outwards from where your DSLR focuses.

[Hoopla]

So thanks to all that commented. Whilst I’m still Terrible at polar alignment after finally getting something resembling a moon I did a little focusing and 💥 here’s the result of my first ZWO shoot. 
 

thank you guys!!!!! 

[KP82]

20 minutes ago, Hoopla said:

So thanks to all that commented. Whilst I’m still Terrible at polar alignment after finally getting something resembling a moon I did a little focusing and 💥 here’s the result of my first ZWO shoot. 
 

thank you guys!!!!! 

 

Get a copy of Sharpcap pro and your polar alignment will be done in no time.

Or if you want something free, either the polar drift align in PHD2 or Polar alignment assistant in Kstars/Ekos will do it for you.