Scope to camera adapter for Epsilon 160ED

You could easily order a Precise Parts adapter to connect the E-160 to the ASI2600. You pick the device on the scope side (the E-160 corrector) and the camera side (ZWO 2600) and add the spacing. The E-160 requires 56.2mm spacing so if the ASI2600 takes up 17.5 mm (which I think includes the tilt adjuster) so your spacing would be 38.7mm. 

That's easy enough, but there's several caveats.

With the E-180, you need to get the backspacing minimally within something like 0.2mm, preferably within 0.1mm. However, the actual back spacing of the ASI2600 is probably within +/- 0.5mm of the spec. Because of that, you would probably want to order the PP adapter a little short, say 38mm and make up the difference with spacers if needed - otherwise the adapter may be too long even if it is to spec.

It's expensive - about $180 USD

There's a wait time of about 4-6 weeks.

It's also not very versatile. If you later decided to add something to the image train, like an OAG, filter tray or tilt plate than that adapter is useless and you will have to start all over again.

You can get sets of M54 spacers of different lengths like this M54 extension tube set which has six spacers from 4mm to 9mm. I also recommend a set of fine machined spacers like these M54 fine spacer set to fine tune the spacing to within 0.1mm

If you go that route, you will also need a male-male gender changer like this M54 male to M42 male adapter

Lastly, a caliper can be very handy to verify the spacing. Nothing too fancy, I use one that's accurate to 0.1mm.

John Hayes:

Paul Wilson:
As an aside, I was told that last year, EVERY mirror for RASA delivered to Celestron was no good.  There were NO new RASAs last year at all, and people with bad mirrors have them sitting there, un-repairable!  We need for equipment to come from places other than just China.

First off, the primary mirrors in the RASA system are spherical.  There is no easier component to make than a concave spherical mirror!  How in the world could they all be bad...for a year?  I'd like to understand that story in a lot more detail.

Second, this isn't a great place to start if you want to go off on a "crummy Chinese equipment" rant.  For years, Synta delivered very high quality optics to Celestron and I'm aware of a number of other high quality optical fabrication shops in China.  If the optics were indeed bad, it's not because they were from China.  It's more likely due to some technical problem but that's hard to say without more facts about what happened.

John

I dont believe I said anything about crummy Chinese equipment.  I said that there need to be more sources of equipment.  Do you see that as a bad thing?  I read 2 comments elsewhere about the bad mirrors.  There are scopes backed up at Celestron that are currently not repairable due to bad mirrors and no replacements.  Not trying to make controversial statements.

Paul Wilson:

John Hayes:

Paul Wilson:
As an aside, I was told that last year, EVERY mirror for RASA delivered to Celestron was no good.  There were NO new RASAs last year at all, and people with bad mirrors have them sitting there, un-repairable!  We need for equipment to come from places other than just China.

First off, the primary mirrors in the RASA system are spherical.  There is no easier component to make than a concave spherical mirror!  How in the world could they all be bad...for a year?  I'd like to understand that story in a lot more detail.

Second, this isn't a great place to start if you want to go off on a "crummy Chinese equipment" rant.  For years, Synta delivered very high quality optics to Celestron and I'm aware of a number of other high quality optical fabrication shops in China.  If the optics were indeed bad, it's not because they were from China.  It's more likely due to some technical problem but that's hard to say without more facts about what happened.

John

I dont believe I said anything about crummy Chinese equipment.  I said that there need to be more sources of equipment.  Do you see that as a bad thing?  I read 2 comments elsewhere about the bad mirrors.  There are scopes backed up at Celestron that are currently not repairable due to bad mirrors and no replacements.  Not trying to make controversial statements.

Interesting, you would think people would be going bananas on youtube etc. F2 on any lens is a razor thin focal plane which is why they had to upgrade their focuser but even still, an EAF is the way to go and I know people have had challenges getting that nailed. That is not even considering if you are using filters what the  bandpass width is and I've heard that on the low end, 12nm is not the way to go but 5nm so a lot of considerations with superfast optics.  The shift is apparently noticeable as distortion unless you are using the correct bandpass width.  At least according to the gurus on the astroimaging channel on youtube.  I'm not sure how many people are aware of all these considerations.  It seems like more of a professional level instrument to get the very most out of it.  Please no one take any umbrage to that statement I don't mean to imply anything about anyone's skill.

Paul Wilson:
I have never imaged with a Newt. So I ordered the E-160ED and I will be waiting for it for, probably, many weeks yet. Or months

I don't know what connects to what on it, admittedly.

Paul,

A few thoughts and a question:

1) Do you know that the M42  connection on the ASI2600 is not going to vignette with the E160ED? The Tak has a M54 corrector - you'll want to maintain that opening for the light cone as close to the sensor as possible. I would be wary to have an M42 bottleneck, even if it is only a few mm from above the optical window of the camera.

2) The ZWO tilt correction unit is going to be incredibly frustrating to fine tune with the E160ED (or pretty much with any OTA that doesn't allow access to the push-pull bolts without removing the camera from the optical train. I can't tell if with the OSC camera you are going to have enough space to sneak an allen key in there and adjust tilt with the camera in place. Also, the ZWO TCU is pretty coarse and unlikely to allow the fine tuning necessary at f/3.3. You already experienced frustration with the RASA, you want to stack the deck in your favor.

3) If you decide to purchase a finer TCU like the Octopi Astro or the ASG Photon Cage, you will not need the M42 constriction on the camera and the camera backfocus will be 12.5mm.

4) Have you given any thoughts to filters that you may want to use? I understand you are using an OSC camera but unless you are always imaging from pristine skies, you may end up using a dual band filter or light pollution filter or Ha filter to supplement RGB imaging of emission nebulae. You could use a filter drawer connected to the TCU (Baader connected to Octopi Astro or ASG homegrown filter drawer on the Photon Cage) if you are not going to use a filter wheel. This will take backfocus that you want to consider and account for.


Finally my question, where did you order the E160ED and were you given a target delivery date? I assume you are in the US. About a month ago I called Tak USA is Houston to ask about ordering a E160ED. I was told that Tak Japan had put new orders of FSQ106 and E160ED on pause because of the huge backlog and that the latest orders they took would be delivered in 2024. If this picture changed or if I was misinformed, that would be fantastic but that's the information I was given.

Cheers,

Luca

Luca Marinelli:

Paul Wilson:
I have never imaged with a Newt. So I ordered the E-160ED and I will be waiting for it for, probably, many weeks yet. Or months

I don't know what connects to what on it, admittedly.

Paul,

A few thoughts and a question:

1) Do you know that the M42  connection on the ASI2600 is not going to vignette with the E160ED? The Tak has a M54 corrector - you'll want to maintain that opening for the light cone as close to the sensor as possible. I would be wary to have an M42 bottleneck, even if it is only a few mm from above the optical window of the camera.

2) The ZWO tilt correction unit is going to be incredibly frustrating to fine tune with the E160ED (or pretty much with any OTA that doesn't allow access to the push-pull bolts without removing the camera from the optical train. I can't tell if with the OSC camera you are going to have enough space to sneak an allen key in there and adjust tilt with the camera in place. Also, the ZWO TCU is pretty coarse and unlikely to allow the fine tuning necessary at f/3.3. You already experienced frustration with the RASA, you want to stack the deck in your favor.

3) If you decide to purchase a finer TCU like the Octopi Astro or the ASG Photon Cage, you will not need the M42 constriction on the camera and the camera backfocus will be 12.5mm.

4) Have you given any thoughts to filters that you may want to use? I understand you are using an OSC camera but unless you are always imaging from pristine skies, you may end up using a dual band filter or light pollution filter or Ha filter to supplement RGB imaging of emission nebulae. You could use a filter drawer connected to the TCU (Baader connected to Octopi Astro or ASG homegrown filter drawer on the Photon Cage) if you are not going to use a filter wheel. This will take backfocus that you want to consider and account for.


Finally my question, where did you order the E160ED and were you given a target delivery date? I assume you are in the US. About a month ago I called Tak USA is Houston to ask about ordering a E160ED. I was told that Tak Japan had put new orders of FSQ106 and E160ED on pause because of the huge backlog and that the latest orders they took would be delivered in 2024. If this picture changed or if I was misinformed, that would be fantastic but that's the information I was given.

Cheers,

Luca

The ASI2600 sensor has a diagonal of 28.26mm. Using this filter size calculator, the minimum size for a filter at 7.5mm from the sensor is 32.59mm so he shouldn't have any vignetting with the 42mm of the tilt plate. The tilt adjustment screws are towards the outer edge of the tilt plate, so they should be easily accessible as long as he doesn't attach a CFW. That said, the screws are way to coarse for the E-160 as you said (I've read people saying it's pretty useless even on slower scopes). As Arun H  mentioned, and Octopi would be up to the task (albeit expensive) and seems to be the tilt adjuster of choice for the E-160. Either way, I think the stock focuser on the E-160 will be more of a problem that will need to be addressed before considering any sort of tilt adjustments or springing for and Octopi.