Hyperstar wizards?

[8324689]

1 hour ago, Elp said:

You can measure it. The start measurement is from the bottom of the thread of the hyperstar (where it reaches physical stop) where you attach the camera side and then any connecting equipment (filter drawer, extension tubes etc) and then finally your front of camera to sensor distance which is supplied by the manufacturer or if you tell us what camera you're using we can advise. You can measure all this whilst it's disassembled, a Vernier caliper will be more accurate if you have one at hand.

The tolerance of the HS backfocus distance is +/- 0.5mm.

The dew heater ring I find is excellent. A dew shield will help prevent dew formation in the first place, it also helps block out stray light entering the OTA which will also improve contrast slightly. If you look at the inside surfaces of the OTA when stray light is entering it, the reflected light off these surfaces is still quite bright so any reduction of this with a dew shield can help. The inside of OTAs should really be coated with vantablack or musou black paint/fabric really in this day and age but it's a more modern innovation so won't apply to previously made telescopes.

`brilliant shall definitely measure it tonight and get back to you 

ALso a dew shield shall give me a resting place for making flats (when i get there)

Edited November 14, 2022 by 8324689

[8324689]

8 hours ago, Elp said:

You can measure it. The start measurement is from the bottom of the thread of the hyperstar (where it reaches physical stop) where you attach the camera side and then any connecting equipment (filter drawer, extension tubes etc) and then finally your front of camera to sensor distance which is supplied by the manufacturer or if you tell us what camera you're using we can advise. You can measure all this whilst it's disassembled, a Vernier caliper will be more accurate if you have one at hand.

The tolerance of the HS backfocus distance is +/- 0.5mm.

The dew heater ring I find is excellent. A dew shield will help prevent dew formation in the first place, it also helps block out stray light entering the OTA which will also improve contrast slightly. If you look at the inside surfaces of the OTA when stray light is entering it, the reflected light off these surfaces is still quite bright so any reduction of this with a dew shield can help. The inside of OTAs should really be coated with vantablack or musou black paint/fabric really in this day and age but it's a more modern innovation so won't apply to previously made telescopes.

@Elp

 

Hi there I’m not sure if I got the placement right but is this correct?

12.3 MM

 

17.5mm for the Risingcam/Touptek

 

NEW 26mp SONY imx571 1.8" APS-C 16bit Zero Amp Glow USB Astro Cooling Astronomy ... Back Focus distance: 17.5mm

 

Ps at the moment the train is HS, spacer, camera  that’s all  

I might add a filter directly later without filter drawer

 

Thanks!

 

Edited November 14, 2022 by 8324689

[Elp]

No.

 

Measure from the physical stop of the HS camera side mounting thread (ledge where I've marked it red because any connecting adaptor will physically stop on this ledge and cannot go any further). 

Measure the thickness/depth of any connecting adaptor (to the bottom physical stop of any male thread, do not include the thread in this measurement because when the adaptors are screwed together the thread doesn't add to the distance because the adaptors become flush with their mating parts unless a gap is left between them when they're fully home, in such a case you'd have to include the gap which is left).

Measure up to the start of your camera at the nose where the arrow "top of m42 mount" touches the camera, I've found this drawing:

Add them all up including the camera front to sensor distance of 17.5mm.

According to the Starizona website the spec for the HS8 is:

Backfocus (from mounting thread to focal plane): 39.8mm (1.57")

So your total distance should fall within the range 39.3mm to 40.3mm if it's right. I would check with Starizona on the backfocus distance though as I've found their website and what they personally advise can be different.

Edited November 14, 2022 by Elp

[8324689]

Hi there

So I found an old email from Starizona and can confirm that my camera needs the ZWO cooled camera adapter. Could anyone tell me the mm sixe of this please so I can check I have the right in posittion?

thanks for all

[8324689]

It should be -> 39.8 - 17.5 = 22.3 +- .5mm

 

Right?

[Elp]

Yes. The 22.3mm remains to be made up with adaptors or spacers. I tend to use, the HS to zwo cooled cam adaptor, zwo filter drawer (21mm) and 11mm camera connector ring, pretty much exact.

The ring is very thin, something like 1-2mm, I'll measure it and come back.

[8324689]

Well thias is great I was WAAYY out before at 17.5+17 (Altair Filter Drawer)+ approx 12.3 = 46.8 

 

I was just so confused and chasing my tail as thinking it was a collimation error and not spacing. No there yet..... but getting there

 

Just waiting for good weather 

 

Thanks to all 

[Elp]

The HS6 adaptor ring to zwo camera ring (it actually fits flush into the zwo filter drawer so the male thread on mine is m48), the thickness is 1.3mm. A HS8 ring may be slightly different.

[8324689]

Tonights the night I reckon! 
I’ll be going in/limbering up ✌🏻

[AKB]

On 13/11/2022 at 22:51, 8324689 said:

 

Is this ok?

 

 

FYI, this is a quick snap I just made for collimation.  Not well collimated, butthe correct spacing and you can see that the images are much more uniform...

 

Edited November 18, 2022 by AKB

[Elp]

Close, looks like it needs to move down a little (the shadow of the central). You can likely image okay as it is.

Edited November 18, 2022 by Elp

[8324689]

2 hours ago, AKB said:

 

FYI, this is a quick snap I just made for collimation.  Not well collimated, butthe correct spacing and you can see that the images are much more uniform...

 

This is brilliant thank you for this. I was really excited as it was forecast to be completely clear tonight but alas it’s the complete opposite

[8324689]

It’s been completely overcast all day! And still is and will be

 

 

[Elp]

Best to use metoffice cloud map, works reasonably well

[8324689]

@Elp

i think Ive found a major issue

My extenders and filter wheel are m48 but HS looks bigger... T2?

Where does the spacing start from please?

a b or c?

 

 

 

 

 

 

 

 

 

 

 

Edited November 20, 2022 by 8324689

[AKB]

On 18/11/2022 at 18:56, Elp said:

Close, looks like it needs to move down a little (the shadow of the central). You can likely image okay as it is.

This shows that I can get collimation closer, but also very clearly demonstrates the curved cable form that I posted earlier in the thread.  When in focus, this means that the diffraction spikes from the cables are very effectively suppressed... definitely worthwhile doing.

The diagonal chip measurement here is 23mm (it's an ASI294-MM.)

 

[AKB]

1 hour ago, 8324689 said:

Where does the spacing start from please?

a b or c?

I would say A.  Effectively from the top of the basic Hyperstar assembly.

[8324689]

OK Thanks 

Would anyone know the length of adapter "C" pls?

 

I cant see how i could measure it with calipers 

[8324689]

ok looks like I need to swap my filter holder for one that attches direct to HS and then converts to m48 so I ca have my spacing exact. 

 

The "C" adapter I measured as 19mm but doesnt seem legit to me as spacing still seems off in photos  

[8324689]

OK so in picture "A" can anyone tell me the size please?

M42, M48 T2 etc?

In essence; all my adapters and filter drawer are m42. Im guessing HS is m48 so I need a m48 to m42 adaptater and Im good .... I hope

 

Edited November 20, 2022 by 8324689

[AKB]

Not sure of the size, but for the ultimate in flexibility in attaching to a Hyperstar, this modular system has everything including variable length spacers…

https://www.firstlightoptics.com/baader-filters/baader-ufc-universal-filter-changer-system.html

…alas, also the ultimate in costs, I suspect.

[Elp]

3 hours ago, 8324689 said:

size

What diameter does it measure at the teeth of the thread? If it's m48 a zwo filter drawer would screw straight onto it, I've got a feeling it's an odd size.

[8324689]

Oh my lord. It ends up I had the wrong spacer in. Im really embarressed and sorry for wasting your time but I am overjoyed!

 

Only issue is now I put a SkyTech LPRO MAX filter in and there is a bit of spacing issue but there was no issue with no filter in.......

Edited November 22, 2022 by 8324689

[8324689]

I forgot the these came out at some point !
 

I’m going  try and put it back in

[Elp]

Good to hear. I find with filters, it requires a slight refocus, though I've never used without as bare minimum I need to use a UV/IR cut filter, so my filter drawer is always attached.

Will look forward to seeing some images, as I guess you will be too, I started a hyperstar imaging thread a few weeks ago in the getting started with imaging subgroup so if you want to contribute you are more than welcome to.