47 replies to this topic

[Monkeybird747]

Yes, thanks to overhearing that Adam Block had managed to cram a 16803 on to his E180 I had to try it on the new E160. This was one heck of a first light trial. Just look at this beast! There's more camera than scope  .

 

 

First I had to sort out the autofocus. I chose the mighty powerful, and mighty cheap, Pegasus focus motor. Since I already have the UPBV2, this was an easy plug-n-play solution that only uses a single ethernet cable to the motor. Its a 12v motor, unlike some of the popular 5v options out there, and has excellent lifting power on the stock focuser. I'm actually REALLY impressed by the stock focuser. I honestly didn't hold out much hope for it, but have been pleasantly surprised. The thing is solid as a rock, and the rotation and focuser travel is very smooth. There is zero slop in the focuser. 

 

So I needed to fashion a support to help take some of the stress off the motor bracket. The focuser only has one bolt you can use to secure the focus motor, and I wanted to give it some additional support for the torque moment. I 3d printed this bracket, and it works really well. The motor mount is solid, and there is no twisting of the bracket at all when under load. The link to this bracket is down below at my Thingiverse page. I can rotate the focuser about 180 degrees before the motor bracket hits the rotation lock knob. This is plenty for a square chip camera. I should be able to make an adjustment and get more rotation if I ever need it.

 

 

 

 

I needed a guiding solution, and since the FLI kit chews up a lot of backfocus I went with a guide scope. For absolutely no good reason I wanted the matching Takahashi 7x50 yellow finder. Spoiler alert: the two yellows are not exactly the same. Sad face. 

 

Legend had it that it was possible to convert a Takahashi finder to a guide scope with helical focuser. If only you could find the correct part. The threads are M51 or some weirdness. I risked it all on Ali Express and found what I needed. Now I have an (almost) matching yellow Tak 7x50 guide scope with helical focuser. Huzzah!

 

 

Since I was in tinkering mode I noticed the Epsilon has a removeable cap on the rear to help cool the primary. It is just a small metal cover with three screws that will be lost in the night at some point. I designed and printed a replacement cap that threads on instead. It consists of a threaded base that uses the existing three screws, and a matching threaded cap. Then I thought, "well why not thread a cooling fan on?". So I made a simple threaded bracket for a 60mm 12v fan that I had lying around. The bonus is that it runs off one of the heater ports on the UPB, so I have remote control and variable speed. I doubt this is really necessary for such a small mirror, but hey why not?

 

 

 

 

 

 

 

 

Now for the data. Its slim pickings from my suburban backyard (bortle 7 red/orange) for widefield right now. I'm able to get a few hours a night on the Cone Nebula, so that's what I chose for this test. First I built a V curve in Voyager. This is one of the best V curves I've seen on one of my systems. I'm using 300 steps of IN backlash compensation. Also, in the UPBV2 firmware I have "Reverse Direction" enabled because of the side I chose to mount the focuser on.

 

This V curve looks like a refractor curve with one of my NiteCrawlers. 

 

 

I got 10 x 600s subs before clouds rolled in. Here is what they look like. I'll post a dropbox link to the raw data since you can't tell much from this resolution. The image scale is around 3.5"/px. Just a tad undersampled .

 

A raw Ha sub:

 

 

Flat Frame

 

 

Flat Contour Plot

 

 

Calibrated Sub

 

 

Integration (10 x 600s)

 

 

Central Region Zoom

 

 

Edge Stars Blocky (No Drizzle)

 

 

Same edge stars with Drizzle magic (not blocky anymore)

 

 

Aberration Inspector

 

 

 

I also learned that from my location with all the stray lights from street and neighbors, plus being at f3.3, I needed a light shield. I was in a hurry, but threw this together quickly so as not to lose any more sky time. It's way too long, but the difference was huge. I have a heated astrozap one on the way. 

 

 

 

 

So I'm calling this a great first light and an unexpected success. I never even considered using this camera/scope combo and have a 268M on order that I thought would be the go to. Now I'm not so sure. I thought that at the least I would have lots of sag/tilt in the stock focuser. I couldn't have been more wrong. The combo produces a monster fov, albeit significantly undersampled with the 9 micron pixels. Obviously the pixel size is allowing me to get away with things at the edges and corners that I might not be able to with something like an IMX455. Still, drizzle recovers resolution nicely so I'm not really worried about that. It also appears my scope arrived in excellent collimation, and I have not intention of touching it anytime soon.

 

Here is the raw data:

 

https://www.dropbox....ThAlCuDjNa?dl=0

 

And here is the link to my 3d files:

 

https://www.thingive...bird747/designs

 

 

 

 

 

 

 

 

 

Edited by Monkeybird747, 25 January 2021 - 03:15 AM.

[rockstarbill]

Results are clear. Excellent performance from the E160ED. My 16803 is dying to get on the scope and first light with the Mach 2 mount. Also of interest is that f3.3 didn't really make the signal with 3nm filters suffer that much. Looks great!

[Complexmystery]

You really pulled this off haha. A beast indeed.....

[ChrisWhite]

Ty,

 

Thanks for sharing.  The camera on that scope looks like a novelty gift gone wrong! 

 

I took a look at your RAW fits and when you really pixel peep stars are not perfectly round anywhere in the frame.  I'm being OVERLY critical here.  The full frame has an Eccentricity of ~0.51.  When I crop it to 2500x2500 to remove the corners the eccentricity is ~0.48.  I'm not an expert on this kind of analysis, but I generally see subs with perfect round stars in the 0.3 to 0.35 range. 

 

What do you think is causing this?  Tilt somewhere due to that crazy heavy setup?  Imbalance with guiding (Doubtful if you are using your 1100)?  So maybe a little collimation error? 

 

Have you had a test with a smaller pixel lighter weight camera?  Would be interesting to see if the result is the same.  Those 9um pixels are a bit more forgiving than something in the 3um to 4um range.  Hoping to see more tests with this scope and the IMX455 sensor, which with that 2" FW would also look a bit ridiculous on that scope!

 

Based on what you are showing here, this performance rivals and beats the FSQ106 for a large sensor.  At half the cost of the FSQ when you consider the focuser upgrades, etc.... this scope is VERY interesting.  With the 16803 and those large pixels any error here does go away with drizzle integration.  Might not be as forgiving for an IMX 455 chip, but out of the box I suspect the results would still be usable. 

 

I've been looking for an FSQ106 for a few months now, but this scope may edge it out.  I'll wait for a little more results from people using the IMX455... but very compelling!

[andysea]

The focuser on my 130 has a tiny amount of flex. Not a problem with my ASi6200 but I can see how a heavy camera may cause flex.

[rockstarbill]

The drizzle integration stack shows a 0.46 eccentricity which is pretty good and it was only integrated from 10 x 5 minute subs, I believe. From a pretty picture perspective you would have to zoom into the image extremely far to see any real issues, and even then they don't appear that bad to me. I would consider this good and not go tinkering and potentially make things worse. 

 

That is a really, really wide field and the chip (52mm) exceeds the spec for the correction (44mm) by a decent amount, yet still looks to be performing quite well. The E160ED results I see here actually look better (to my eye) than the results on the Adam Block E180D system.

[Monkeybird747]

Ty,

 

Thanks for sharing.  The camera on that scope looks like a novelty gift gone wrong! 

 

I took a look at your RAW fits and when you really pixel peep stars are not perfectly round anywhere in the frame.  I'm being OVERLY critical here.  The full frame has an Eccentricity of ~0.51.  When I crop it to 2500x2500 to remove the corners the eccentricity is ~0.48.  I'm not an expert on this kind of analysis, but I generally see subs with perfect round stars in the 0.3 to 0.35 range. 

 

What do you think is causing this?  Tilt somewhere due to that crazy heavy setup?  Imbalance with guiding (Doubtful if you are using your 1100)?  So maybe a little collimation error? 

 

Have you had a test with a smaller pixel lighter weight camera?  Would be interesting to see if the result is the same.  Those 9um pixels are a bit more forgiving than something in the 3um to 4um range.  Hoping to see more tests with this scope and the IMX455 sensor, which with that 2" FW would also look a bit ridiculous on that scope!

 

Based on what you are showing here, this performance rivals and beats the FSQ106 for a large sensor.  At half the cost of the FSQ when you consider the focuser upgrades, etc.... this scope is VERY interesting.  With the 16803 and those large pixels any error here does go away with drizzle integration.  Might not be as forgiving for an IMX 455 chip, but out of the box I suspect the results would still be usable. 

 

I've been looking for an FSQ106 for a few months now, but this scope may edge it out.  I'll wait for a little more results from people using the IMX455... but very compelling!

Overly critical is welcome. They stars are not perfect, but mostly look good to my eye. At 3.47"/px I don't see anything that would concern me at all, but I generally try no to get too spooled up on star shapes in widefield images. If I had those measurements on 12.5" I might be more inclined to investigate. When I put a smaller pixel camera on there I'll check again. I bought the 268M just for this scope, but when some of the other manufacturers get their hands on the IMX455 I'll probably get another full frame chip for it. I had a 294M ready to go, but there seemed to be possible issues with the implementation of that sensor in the QHY version. I didn't want to risk missing my return window waiting for that to get fleshed out, so I returned it for a refund. 16803 is the only camera I have at the moment.

 

That being said my FLI and CFW 5-7 have a known amount of top to bottom tilt. I believe this comes from the connection method between camera and wheel, which uses a dovetail at the top of the camera, and two bolts at the bottom. I use a Gerd to easily correct it on the idk, but no room on this system. You can see this is the FWHM plots in the eccentricity script. 

 

Speaking of the FWHME script, make sure you are not measuring too many stars since so many are severely undersampled. I run the PSF Image render script first, adjusting sensitivity until I get 700-1000 stars detected. Then look at the beta value, and use the Moffat model that is the closest match to that number. In this case I used sensitivity of .5 and Moffat 2.5 in the FWHMEccentricity script. That measured about 700 stars, which hopefully are well sampled, and excludes the ones that are made up of only 9 pixels or so. It doesn't change the measurement by that much, but the full frame of the sub I used came out to .48, and a 50% central crop measured .42. All things considered, I think that is really good for f3.3. But the eyeball is the only real judge that matters.

 

It is certainly an alternative to the FSQ worth considering.

[Monkeybird747]

The focuser on my 130 has a tiny amount of flex. Not a problem with my ASi6200 but I can see how a heavy camera may cause flex.

That's what I was expecting, but I really can't detect any in this focuser. Surprisingly solid feel. It could be there I and just can't notice it by eye. 

[rockstarbill]

Speaking of the FWHME script, make sure you are not measuring too many stars since so many are severely undersampled. I run the PSF Image render script first, adjusting sensitivity until I get 700-1000 stars detected. Then look at the beta value, and use the Moffat model that is the closest match to that number. In this case I used sensitivity of .5 and Moffat 2.5 in the FWHMEccentricity script. That measured about 700 stars, which hopefully are well sampled, and excludes the ones that are made up of only 9 pixels or so. It doesn't change the measurement by that much, but the full frame of the sub I used came out to .48, and a 50% central crop measured .42. All things considered, I think that is really good for f3.3. But the eyeball is the only real judge that matters.

 

It is certainly an alternative to the FSQ worth considering.

The PixInsight documentation says that 0.42 is not perceptible to most people. Traditionally I keep frames that are 0.5 and below. I would be happy with the results you got with that large of a chip, and that heavy of a camera/fw combo. 

[Monkeybird747]

Someone asked about the QHY. I did actually mount it up and tested the clearance and rotation. The drawtube is extended to thread on the OAG, but it can be lowered to the full in-travel position with no problem. I have since moved my top plate back a little and could get close to 360 degree rotation now. But, I chose the QHY because of the dovetail connection. My intent is to leave the focuser in one position, and use the qhy dovetail to rotate and frame the image. 

 

 

Here is a video. This is the QHY294M, CFW3 5 position (standard thickness) for 2" filters, and the QHY-M OAG. After all that I think about 8mm of spacers were needed, which go on the front of the OAG and provide additional clearance. In the clockwise rotation the motor housing eventually contacts the focuser rotation lock knob. This could be mitigated if it was really important to you to hit that particular rotation position for some reason.

 

https://www.dropbox....G_9195.MOV?dl=0

[syxbach]

Looks awesome. For the video, your focuser body is out for ~10 mm. I wonder if you can make the focuser to the zero position (or close to zero position). I am worried if the OAG will be blocked by the focuser housing. Thanks!

 

Yuexiao

 

 

 

Someone asked about the QHY. I did actually mount it up and tested the clearance and rotation. The drawtube is extended to thread on the OAG, but it can be lowered to the full in-travel position with no problem. I have since moved my top plate back a little and could get close to 360 degree rotation now. But, I chose the QHY because of the dovetail connection. My intent is to leave the focuser in one position, and use the qhy dovetail to rotate and frame the image. 

 

 

 

Here is a video. This is the QHY294M, CFW3 5 position (standard thickness) for 2" filters, and the QHY-M OAG. After all that I think about 8mm of spacers were needed, which go on the front of the OAG and provide additional clearance. In the clockwise rotation the motor housing eventually contacts the focuser rotation lock knob. This could be mitigated if it was really important to you to hit that particular rotation position for some reason.

 

https://www.dropbox....G_9195.MOV?dl=0

[ChrisWhite]

I wouldn't have measured if my eyes had not seen it first.

 

I agree with your assessment though that it is very minimal, and for widefied... hardly a concern. 

 

Will be interesting to see how it performs with small pixels.  I also ordered a 268M, and I'm hoping to use it on my reduced AT92.  I doubt it will look as good as what you have just presented, and if I'm dissatisfied I might pickup a 160ED and match it with my 6200.... putting the 268M on my EDGE. 

Edited by ChrisWhite, 25 January 2021 - 01:45 PM.

[rockstarbill]

I wouldn't have measured if my eyes had not seen it first.

 

I agree with your assessment though that it is very minimal, and for widefied... hardly a concern. 

 

Will be interesting to see how it performs with small pixels.  I also ordered a 268M, and I'm hoping to use it on my reduced AT92.  I doubt it will look as good as what you have just presented, and if I'm dissatisfied I might pickup a 160ED and match it with my 6200.... putting the 268M on my EDGE. 

For the price, the E160ED is quite the performer. Did you download his integrations or just the single raw sub? The stacks look pretty good, you may want to check those out if you have not already.

[syxbach]

You can check out this. 455 is already tested on this scope. Pretty good. I cannot find a reason for a smaller chip on this scope.

 

https://www.astrobin.../users/grapeot/

I wouldn't have measured if my eyes had not seen it first.

 

I agree with your assessment though that it is very minimal, and for widefied... hardly a concern. 

 

Will be interesting to see how it performs with small pixels.  I also ordered a 268M, and I'm hoping to use it on my reduced AT92.  I doubt it will look as good as what you have just presented, and if I'm dissatisfied I might pickup a 160ED and match it with my 6200.... putting the 268M on my EDGE. 

[lucam]

This definitely gives me scope envy. The new e160 looks really good!

[Monkeybird747]

I wouldn't have measured if my eyes had not seen it first.

I agree with your assessment though that it is very minimal, and for widefied... hardly a concern.

Will be interesting to see how it performs with small pixels. I also ordered a 268M, and I'm hoping to use it on my reduced AT92. I doubt it will look as good as what you have just presented, and if I'm dissatisfied I might pickup a 160ED and match it with my 6200.... putting the 268M on my EDGE.

It does look promising. The 268 would be really good on this scope I would think. Same for the full frame cmos cameras. I guess there already a few users with full frame data, but I haven’t looked at any of it.

I was a little concerned about my standard f4 3nm filters. Data looks ok, but without comparing size by side with high speed filters it’s hard to say if I’m losing any appreciable signal.

[Monkeybird747]

I wouldn't have measured if my eyes had not seen it first.

Yep, that’s what I meant. That your eye is better than any measurement. Didn’t mean to imply otherwise. 😋

Edited by Monkeybird747, 25 January 2021 - 02:29 PM.

[Monkeybird747]

Looks awesome. For the video, your focuser body is out for ~10 mm. I wonder if you can make the focuser to the zero position (or close to zero position). I am worried if the OAG will be blocked by the focuser housing. Thanks!

Yuexiao

No problems. I tested full focuser travel. It just happened to be out when I took the picture. You won’t get 360 degrees of rotation with the Pegasus, but it’s probably enough to suit most framing scenarios.

[ChrisWhite]

No problems. I tested full focuser travel. It just happened to be out when I took the picture. You won’t get 360 degrees of rotation with the Pegasus, but it’s probably enough to suit most framing scenarios.

Yep, you only need 135 degrees of rotation to frame in any orientation with a rectangular sensor. Nice work on the printed mount.

[ChrisWhite]

You can check out this. 455 is already tested on this scope. Pretty good. I cannot find a reason for a smaller chip on this scope.

https://www.astrobin.../users/grapeot/

Cool. Just 1 corner looks a little funky. Very good performance.

[AstroGabe]

Excellent result!  Thanks for sharing your detailed writeup.  Your frame looks great with minimal distortion at the edges.  

 

Here's an analysis I ran w/ my inspector tool.  There's some slight coherent elongation on the left side, which as was mentioned may be due to the weight of the camera.  Overall it looks like a fantastic performer!

 

I'm eager to get a first light with mine and the ASI6200MM.

 

[Monkeybird747]

Excellent result!  Thanks for sharing your detailed writeup.  Your frame looks great with minimal distortion at the edges.  

 

Here's an analysis I ran w/ my inspector tool.  There's some slight coherent elongation on the left side, which as was mentioned may be due to the weight of the camera.  Overall it looks like a fantastic performer!

 

I'm eager to get a first light with mine and the ASI6200MM.

 

newplot (20).png

newplot (19).png

Cool analysis Gabe!

 

[Ballyhoo]

That is one adult toy you got capt. 

[rockstarbill]

That is one adult toy you got capt.

Not sure what you mean....

[Shannon Foye]

Excellent result!  Thanks for sharing your detailed writeup.  Your frame looks great with minimal distortion at the edges.  

 

Here's an analysis I ran w/ my inspector tool.  There's some slight coherent elongation on the left side, which as was mentioned may be due to the weight of the camera.  Overall it looks like a fantastic performer!

 

I'm eager to get a first light with mine and the ASI6200MM.

 

newplot (20).png

newplot (19).png

Gabe - That is a clever tool you have developed. I was going to ask you where I could find the software, but I searched and found your discussion of the tool on the Voyager forum. Your combined display (not shown above) of FWHM size, eccentricity amount, and eccentricity direction is brilliant.

 

Ty - Thanks for providing the pictures and details of how you’re setting up this scope for imaging. Very informative for someone interested in the new Epsilon.

Edited by Shannon Foye, 27 January 2021 - 06:02 AM.