21 replies to this topic

[Bokchoy Ninja]

I have my redcat51 V2 set up, with all the usual gadgets except for an autofocuser. Given the focusing mechanism, it would take a bit of fiddling to 3D print and collect the required parts.

 

But, it's a pretty short focal length optic, so I wonder if people experience the need to refocus throughout an imaging session? Filter changes are another avenue for focal shift but they're supposed to be parafocal. I'll have to actually check if I get a clear night soon.

Edited by Bokchoy Ninja, 08 May 2024 - 10:46 AM.

[Acenspades]

I have an EAF on my RC51 V1 and from my experience it makes a difference comparing when i didnt have an EAF to now with an EAF.

I refocus every 1 hour (set in my super simple and ez to use ASI Air) and/or when i change filters.

[unimatrix0]

In my experience, there is no such a thing as overkill when it comes to perfect focus. 

You can achieve good results with a Bathinov mask, but you will never match the autofocuser work with algorithm developed to determine the best focus position based on calculation done on star sizes.  

 

BTW you can also buy already made, 3d printed parts for the redcat. 

Edited by unimatrix0, 08 May 2024 - 10:54 AM.

[Bokchoy Ninja]

In my experience, there is no such a thing as overkill when it comes to perfect focus. 

You can achieve good results with a Bathinov mask, but you will never match the autofocuser work with algorithm developed to determine the best focus position based on calculation done on star sizes.  

 

BTW you can also buy already made, 3d printed parts for the redcat. 

Fair enough. Then it'd be harder to justify having bought a 3D printer haha.

[Bokchoy Ninja]

I have an EAF on my RC51 V1 and from my experience it makes a difference comparing when i didnt have an EAF to now with an EAF.

I refocus every 1 hour (set in my super simple and ez to use ASI Air) and/or when i change filters.

Fair enough. What focusing system do you use?

[auroraTDunn]

Yes, you should use an EAF as it helps to provide the best data. As temperature changes so does everything in your setup. minor but for sharpness it matters. If you use filters, even if parafocal there will be differences and looking at my logs (and I use and swear by pretty expensive Astrodon filters) they are not all that subtle, definitely enough that it will make a difference.

 

But the answer is it depends on what you are shooting, the more extreme you go, and there are many avenues of extreme the more the difference may be seen. So don't get me wrong, you can get really good results without one but if you want setup then run all night, sometimes on different targets with or without meridian flips AND you want to have a sound nights sleep, an EAF is a dang near must!

 

As to what I use, I have a dang near pure ZWO setup (WHERES MY ROTATOR GUYS!?!)  on my RC71 so I use the ZWO EAF. And for the mount I use the one by DeepSkyDad and LOVE it I have used and abused it hard and it has never given me any pause or thought!

 

I have others on other, older, packed away, rigs but my RC+ZWO is way and by far my favorite from more then half a century of doing this! Take your time, it's a very expensive life, but sooooo worth it.

[Rich_]

I use the Pro Astro Gear Black Cat mounting system with my Redcat51. This allows you to install a ZWO EAF and other items, such as an ASI and a guidescope when used with the original cat handle. Check thingiverse to see if there are copy cat versions of the same concept (although it's not too expensive to buy).

https://www.firstlig...-redcat-51.html

Auto focusing is essential if you want to image overnight whilst you sleep. Some nights the focus can stay relatively stable, other nights it can change quite a bit. The time saved on getting an accurate initial focus over manual focus with a bahtinov mask is worth the investment alone.

Attached is a picture of my Redcat51 with ZWO EAF, Pegasus Powerbox Advance, 32mm guide scope and mono setup attached. The AF routine works perfectly well with all my LRGB-SHO filters

Attached Thumbnails

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Edited by Rich_, 08 May 2024 - 12:02 PM.

[hyiger]

Fair enough. What focusing system do you use?

This is my RedCat 71 which is similar. I used the all metal adapter kit from https://deepskydad.com/ I had tried a 3D printed bracket but had issues keeping it tight. The EAF mounts underneath with riser blocks on the dovetail. I'm not as wide as you but there is a night and day difference between using an autofocusser and a Bahtinov mask. Also, with an autofocusser I don't need to be near the scope. 

 

Edited by hyiger, 08 May 2024 - 12:01 PM.

[hyiger]

As to what I use, I have a dang near pure ZWO setup (WHERES MY ROTATOR GUYS!?!)  on my RC71 so I use the ZWO EAF. And for the mount I use the one by DeepSkyDad and LOVE it I have used and abused it hard and it has never given me any pause or thought!

I even have the RedCat Edition AM3  Oh and the RC71 is the best scope I've ever owned. The optics are amazing. 

 

Yep, the DeepSkyDad version is better in my opinion. I'm sure it's a short matter of time before ZWO comes out with a rotator. 

 

Edited by hyiger, 08 May 2024 - 12:07 PM.

[hyiger]

Fair enough. What focusing system do you use?

I use both the ASIAir and HocusFocus plugin for NINA (depending on my mood)

[fmendes]

It's mostly peace of mind. I designed and printed my own EAF parts. Instead of the fancy (and nice) ZWO stuff, I use MyFocuser Pro2. Start here:

 

https://www.thingive...m/thing:5600585

 

A cool thing, this hardware is interchangeable with the Rokinon 135mm. The MyFocuser Pro firmware needs a tiny tweak to allow powering from USB only (value of a constant needs to be changed), but works like a charm. And most important, other than the printed parts, hardware to make 3 EAFs costs less than $40.

Edited by fmendes, 08 May 2024 - 12:14 PM.

[Bokchoy Ninja]

It's mostly peace of mind. I designed and printed my own EAF parts. Instead of the fancy (and nice) ZWO stuff, I use MyFocuser Pro2. Start here:

 

https://www.thingive...m/thing:5600585

 

A cool thing, this hardware is interchangeable with the Rokinon 135mm. The MyFocuser Pro firmware needs a tiny tweak to allow powering from USB only (value of a constant needs to be changed), but works like a charm. And most important, other than the printed parts, hardware to make 3 EAFs costs less than $40.

Nice. Do you know whether the ASIAIR would run those?

[DanMiller]

To me, an autofocus main advantage is for when you are doing long imaging sessions.  Over night.  As the temperture changes, the weather changes, the seeing changes.  Having an automatic autofocus gets you the best data.  With N.I.N.A. advanced sequencer, you can have auto focus run under the following conditions.

1). If you have automated the changing of a filter, you run the autofocus and before you begin imaging again.

2). If the stats of the stars change by a specific threashold, you can have auto focus run.  I really don't like this one because you could have a cloud passing that degrades your stars.  I would rather throw out the specific frame then take the time for the auto focus to run.

3). After a specific number of images taken, you can have auto focus run.

4). This is the one I use.  I auto focus every hour.  Not sure if that is the sweet spot, but that is what I currently use.

 

So, as you can see.  Having the ability to automatically run an autofocus can save you from being at the mount for performing a focus.  And it also can be tailored to your needs.

 

Dan

[hyiger]

Nice. Do you know whether the ASIAIR would run those?

ASIAir can only use ZWO cameras, select DSLR, many different mounts, ZWO EAF and ZWO EFW only. 

Edited by hyiger, 08 May 2024 - 04:12 PM.

[Bokchoy Ninja]

ASIAir can only ZWO cameras, select DSLR, many different mounts, ZWO EAF and ZWO EFW only. 

Go figure...

[fmendes]

Go figure...

 

Their business model. "You want to use our nice solution, can only use our hardware". I see an ethical conflict with Asiair, as it uses INDI that is an open platform for proprietary purposes. In other words, they steal from the community.

 

MyFP has both ASCOM and INDI drivers and there's no technical challenge to make it run on Asiair. Only barrier is ZWO.

[hyiger]

Their business model. "You want to use our nice solution, can only use our hardware". I see an ethical conflict with Asiair, as it uses INDI that is an open platform for proprietary purposes. In other words, they steal from the community.

 

MyFP has both ASCOM and INDI drivers and there's no technical challenge to make it run on Asiair. Only barrier is ZWO.

 

Go figure...

A Mele Quieter 4C running NINA or SharpCap is an excellent alternative. Also, iOptron iMate which runs kstars/ecos

 

I have an ethical problem as well with the ASIAir which is why I'm weaning myself off of it. Once they release their source to github I'll reconsider. 

Edited by hyiger, 08 May 2024 - 04:16 PM.

[Acenspades]

Fair enough. What focusing system do you use?

With the RC51 V1 i have attached a ZWO EAF and run my whole imaging routine through the ez pz but very capable ASI Air

[DanMiller]

I spent my whole life in I.T.  People using other peoples work does matter. Especially when their is a license that defines terms.  ZWO is just like apple and many other control freak coperations. They lock you into their product and you can't get lose.  Why don't you read the stories where major buisnesses get locked into products(Oracle, MicroSoft) and they spend millions when they try to change.  All brands have their bad side. And ZWO is no different.  Please, I upgraded their firmware on an EAF and I had to use SOMEONE ELSES software to fix where it would not move either with the hand controler(theirs) or with software the full range.
 
If you place all your eggs in one baskete, you burn your self when you find something else you want to use.  The ONLY reason I have problems is because of lack of funds.  Not that I have various brands.  It really is as simple as that.  
 
Dan

[DeepSky Di]

I use an EAF with my RedCat 51 V2, using the cog driven adapter. I have a belt driven adapter for my Samyang 135.

 

It's totally worth running an EAF.

[PIEJr]

I built my first focuser with 12 volt stepper motors, but it wasn't automatic.

Then when I was getting serious I bought an ASI EAF and got the latest of the greatest at the time, the 5 volt one.

At first I was quite enthralled with it. Then I discovered it would run fine moving outward, but would arbitrarily stop moving the focuser inward.

And it could not find focus with the arbitrary stopping. So back to ZWO customer service in New Jersey.

They claimed they could not replicate the problem and sent it back. I had put tiny dots at screws and places so I could tell if they had opened it. My first step to check their quality control.

They hadn't done anything by run it, as far as I could tell.

I tried it on both my 80mm Crayford telescope, and on my AT 130mm. Neither could find focus with the misbehaving EAF.

 

I figured it was going to be a PITA, so I found a Pegasus Astro focuser with much better attributes, including a full 12 volt drive.

 

I had to make ZWO a movie of what the focuser was doing and post it so they could watch it. I was able to PROVE to them mine was defective and teach them how I troubleshot the malfunction.

Not good customer service at all. But very typical of the Chinese business model I've encountered over more than a decade. They will never refund a purchase, even though their warranties say they will, at their discretion.

 

So I can highly recommend Pegasus Astro Focus Cubes over any ASI EAF.

 

Oh, and after 6 weeks later they did replace the faulty ASI EAF. It now lives on the 80mm that we use for visual observing. The Grandkids love not having to touch the telescope to adjust the focus from kid to kid with the hand control I bought for it to help prove mine was defective.

When manually focusing having it stop is no big deal, just touch the button again.

Makes me remember a Toby Keith song.

 

An Automatic Electronic focuser makes a huge amount of difference in the quality of the images you are trying to take. There is a lot going into keeping you focused.

HDR, Temperature, Analytics, things you and your fingers don't do. All working automatically to get you sharp clear results.

Edited by PIEJr, 09 May 2024 - 12:39 AM.

[WadeH237]

Just a note from your friendly neighborhood moderator:

 

The first rule of Cloudy Nights is Play Nice.  I have removed a bunch of posts of people sniping about licensing.  If you have something to say, please say it nicely.

 

Also, please stay on the topic of autofocus with the RedCat 51.  Vendor lock-in and licensing are relevant to choosing a focusing solution, but isn't the main point. If that becomes the focus of further replies, the topic will likely be locked.

 

Thanks!