Setting up the E160-ED for Full Frame Imaging Takahashi Epsilon-160ED · Dark Matters Astrophotography · ... · 1655 · 60489 · 369

Got my Hercules installed. Super easy upgrade from the LEO. Only issue was that I wasn’t able to connect to the serial port. Turns out they sent me the wrong cable — a USB/Serial cable like the one that comes with the LEO, but the Hercules connects via USB-C. Once Jeff D. spotted the error, I swapped in a USB-C cable I had on hand and all is well. 

Just doing some cable management and I’ll be ready to test. Speaking of cable management, Chris won’t advertise for himself, but y’all need to check out the E-160 related tools he sells via his Overcast Observatory website. His side saddle mount and UPv2 cable management system are making cable management easy.

The focuser does not change the backspace at all. The focal plane does not change no matter what focuser you have on there. Backspace refers to the distance between the corrector and the sensor.

Chris White- Overcast Observatory:
The focuser does not change the backspace at all. The focal plane does not change no matter what focuser you have on there. Backspace refers to the distance between the corrector and the sensor.

Yes, the backspace doesn't change, but the amount of it taken up by the focuser/rotator can eat into the backspace, right (like if the Hercules were 70mm thick, we couldn't use it in our E-160s)? I don't mean we get any MORE backspace (above the 56.2mm), but that we don't eat into that 56.2mm from the Hercules, where as my Falcon rotator sure did. Right? Don't harsh my mellow, man! Trying to fit a FW & rotator and OAG (which I never use, but others, do) has been tough on many. Don't destroy my DREAM!!!

You know I love you man, I would never harsh your buzz. 

But let's clarify for the sake of ... clarity. 

You must have 56.2mm between the corrector and the sensor to have a flat field. That's a given. If the focuser were too thick, then you simply wouldn't be able to reach focus. While you could technically reach focus by reducing your backspacing, you'd no longer have a flat field. So the focuser is what it is. Assuming you have 56.2mm spacing then it either works or it doesn't. The Hercules was engineered to be the same thickness as the Leo. So in that sense it's the same and doesn't gain you anything. Of course, not needing a falcon is a huge win and getting rid of that DOES gain you available spacing to use for other accessories or simply a spacer. The other advantage is that the Hercules is a precision instrument. Falcon can't claim that. Jeff recently measured my gemini rotator and it was within 5um of flatness through the rotation cycle. Now that is seriously good engineering from that company. 

Enjoy your mellow man. You get to eat your cake and have it too. :-)

Congrats!

Look, I'm a PROFESSIONAL writer!!! I normally get paid to get words and phrases wrong and uncleary (look it up - it's not a word). I'm not gettin' paid here!

No, you are right, of course. I didn't mean to imply that. I only meant that they built the Hercules in such a way that you basically regain the space you lost if you had a rotator in your optical chain...which I think is pretty great/miraculous/magical since things are pretty tight on our E-160s. So there!!!

I did not get a chance to see how accurate the rotator was since I had some tilt, but the tilt appeared to be similar from one rotational position to the next as I looked at the subs this morning. When I get the tilt adjusted, I'll be able to see fairly clearly (NOT cleary - which IS a word...LOOK IT UP!).

Quick question: as per this thread, I got a ZWO filter wheel (sent back my Pegasus Astro), and do their filter centering masks work? I put in the Buckeyestargazer filter centering masks, and I wonder if tilt can be introduced with those.

UNCLEARY, MAN!!!

(Oh, and I blame this all on the fact I got very little sleep last night, so there!)

No, your filter masks can't cause image train tilt. Sorry. It's much more complicated than that. if this harshes your buzz it's not my fault!

Quick question for those who've used a Leo or Hercules (the settings should be the almost the same) with Hocus Focus. I know the step size is 0.079 microns for the Hercules, but what should I put for steps and step size? I know I'm being dumb here, but I'd like to get this right.

Thanks!

Muchas gracias! You are a gentleman and a scholar.

I received my Hercules focuser/rotator and will attempt installation tomorrow. The scope is very well set up now, so it is a risk but the high reward will be a much better focuser and rotation, of course. Any tips from those that have already installed it? Anything to look out for?

Also, I wonder if anyone is running the Hercules (or Leo) with ZWO EFW + ASI 6200 + Photon Cage with an OAG. Does anyone know if the Pegaus Indigo OAG will fit in this imaging train? I can put a small guidescope but this rig is going remote and I would love to have it with an OAG, which I like better.

Thanks!

You may want to reach out to Optec and Jeff about that.  I had the same issue, focus was about 0-5000 steps out of 112,000.  They machined and sent a lowered saddle plate and it fixed it.  I can focus now right at around 56,000 steps.  They were great about it, but worth talking to them and they seemed really helpful in getting it right.

As a side note, I"m glad that EAT is working good.  I put one on this epsilon, probably same configuration and it's performing well on this one.

Josh Jones:
You may want to reach out to Optec and Jeff about that.  I had the same issue, focus was about 0-5000 steps out of 112,000.  They machined and sent a lowered saddle plate and it fixed it.  I can focus now right at around 56,000 steps.  They were great about it, but worth talking to them and they seemed really helpful in getting it right.

As a side note, I"m glad that EAT is working good.  I put one on this epsilon, probably same configuration and it's performing well on this one.

Good idea — will contact Jeff. Definitely would like another 10,000 steps at a minimum.

Josh Jones:

Chris White- Overcast Observatory:

Quick question for those who've used a Leo or Hercules (the settings should be the almost the same) with Hocus Focus. I know the step size is 0.079 microns for the Hercules, but what should I put for steps and step size? I know I'm being dumb here, but I'd like to get this right.

Thanks!

I'd start with 4 steps and 900 or 1000 for the step size.

That is where I ended up with.... 900 step size and about 100/100 on backlash started giving good focus curves.

I had it at 200 step size. Changed to 1000 and everything great now. No backlash compensation needed though - I was under the impression the Leo has no backlash?

Is the EAT available for purchase? I am sending my Epsilon to a remote observatory next week with a regular Photon Cage. It sure would be nice to be able to do that part remotely if needed

Josh is the one to ask. I purchased mine as part of a limited initial run and for the same reason, to enable a worry free remote deployment.

Josh asked me if I would field test the prototype ASG EAT last winter/spring so I've had a ton of experience using it by now.  I used it on several different scopes including epsilon and it has been a dream.  For those of you who don't know, I am a bit obsessive about seeing what the optics are capable of, and that means dialing in spacing and tilt to micron level tolerances when using a full frame sensor.  I have found the EAT to be extremely precise and repeatable with its movements.  We all get hung up on tilt, but spacing is super critical with scopes like epsilon, and the EAT makes it very easy to adjust.  Basically, I tested it at 50um spacing changes until I got it really optimal.  Doing that with a manual tilt device is possible, but it takes a fair amount of time at the scope to make adjustments and they are not always easily perfectly repeatable. 

I actually zeroed the unit out several times in my epsilon testing and could fix 95% of the tilt within about an hour from my living room.  Pretty amazing when you consider just how challenging it is to work on a system like epsilon.  After several months of field testing, I bought a production unit and put it on my AP110 that was just installed at HCRO in New Mexico.  The other night I spent about an hour fixing tilt (from about 2500 miles away) and got an excellent quality field.  Since it's the new moon I didnt want to spend any more time on it, so once we get to the full moon I'll dial in that last little bit.

There are a couple of things I would like to point out for those of you thinking of incorporating EAT into a remote deployment. 

1) The motors do not have encoders, so you can lose where you are if you accidentally zero things out in the software, or if the motors get moved while the unit is powered off.  I believe Josh told me that it would be cost prohibitive to have encoders, especially for bringing a novel product like this to the market.  So you need to be mindful of this….  My scope rode on a pallet across the USA for a week in trucks, and all the vibration and weight of my camera caused the motors on top (as it was positioned) to spool out.  I noticed something was way off when I first logged in when tilt was way worse than i expected.  Even though I had zeroed it out, the motors moved a bit.  I was worried about something like this happening and concerned that it would be difficult to address, but it turned out to be super simple.  I asked the tech to measure the thickness of the two lower plates with a set of calipers, and discovered that the upper part was 1mm wider than the lower.  So yeah, 1mm of tilt!  Thats a problem.  It took maybe 10 minutes of the tech taking measurements, and me making some adjustments to get it all flat again.  Then I zeroed it out and had a new starting point.  Problem solved. 

2) Related to the above…. once you figure out which motor in the UI belongs with the motor in real life…. LABEL THEM WITH A MARKER!   I did this before I shipped, so the tech knew he was measuring Top Right or Top Left (based on my labels) and I knew exactly which motor to move to get it to flat.  Otherwise we might have played a guessing game for a bit.  So label them so you know which motor adjustment in the UI moves Which motor at the scope. 

3) The UI is pretty basic, which is totally ok… but because the upper left motor in the UI might not be the upper left corner of your sensor you need to become well acquainted with all of the orientation.  It was more complicated in my case because I use a QHY camera and ZWO filter wheel.  Once I figured it out, I made a basic spreadsheet in Excel that I could input the tilt measurement output from NINA or ASTAP that would convert that to which corner that corresponded with in the UI.  This way I didnt have to think about orientation. I could run the ASTAP analysis and then I knew which motor to adjust.  Figure all of this out well before you deploy and take photos of the setup, label things and make notes.  Josh is working on the UI to help with orientation (which reminds me I need to reply to one of his emails about this) but even if he adds some bells and whistles to the software, you still should become familiar with everything on the UI and how it relates to the scope.  Your remote site technician will thank you. 

It's an pricey convenience factor, but if you want to get the most out of your investment then it's a no-brainer.  For the kit I sent to New Mexico, I have a ton of $$ invested once you break down all the bits and pieces…  While the gear is capable of producing perfectly round stars to the corners, it takes significant effort to dial it in.  I found that the $2500 for the EAT was a smart purchase for me to be able to do it from the comfort of my home and with relative ease.  I couldnt imagine trying to talk a tech through dialing in tilt with a manual tilt device.   Talk about a recipe for frustration…..  It takes me hours to do it by hand and I have tons of experience with tilt and spacing analysis and mitigation!   Plus if I want to swap in a different flattener for galaxy season I can just have the tech swap it out and if there is any tilt take care of it remotely.  For those with epsilon, think about the 1.5x extender.  Would be killer for galaxy season.

Ani Shastry:
The one thing I do wish was that the software had different profiles; where I could tune the tilt for any particular rotation angle of the imaging train and have the EAT snap to that. And it would be awesome to expose the tilt profile as an instruction in the advanced sequencer in NINA.

This is an interesting idea.