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Tak Epsilon 130 in the dark!

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#1 tim53

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Posted 01 July 2013 - 01:00 AM

So, this is rather embarrassing.

I brought the Epsilon, complete as purchased, figuring I'd do some astrophotography under the beautiful dark Milford skies. And everything seems to be in order and working well.

Only I don't have a 2" eyepiece adapter, so I can't use 2" eyepieces in my 2.7" focuser, which just seems silly!

So I gee whizzed a while as I was waiting for the clouds to dissipate. And they have, so I got out my easiest camera first - the Pt Grey scorpion with the 1 1/4" nosepiece, and stuck that puppy in. Well, it couldn't go in far enough to reach focus, so I put in a 2x shorty barlow and could focus. But then, it's not a simple system and a machine vision camera isn't the best for DSOs (but it'll work). So...

...I had gotten a key code for the 30 day trial for Backyard EOS for my Canon T1i. ...only I don't have an adapter to put it on the scope, unless I use the 2" Meade barrel which will fit on one of the Tak adapters but - you guessed it, I can't reach focus.

Same with my Panasonic Lumix GF3. So I was poking through the stuff that came with the scope and got to the Bushnell branded camera adapter. It's a t-thread to camera, but the camera isn't anything I own. Not Canon, Nikon, Konica or Exakta. But the adapter screwed into the t-threads on the Bushnell is apparently a Tak part, but I couldn't get it off the t-adapter because there are eensy set screws holding it on. And I don't have a set of jewelers screwdrivers with me.

I just about gave up, when it occurred to me that the diameter of the bayonet of whatever it is was at least a slip fit onto the Konica to Lumix adapter that I bought so I could use my Konica glass with the Lumix. So, I got out the trusty duct tape and made them one!

So now it works!

The Lumix can only take up to a minute exposures so I'll be doing a lot of subs to see if I can stack and improve on them. I'm also hoping that at such a short f/ratio (130mm f/3.3) that the Tak EM-1 mount will be accurate enough that I won't have to guide - which would require I make some rube goldbert contraption out of another lens and one of the Pt Grey cameras!

While we're waiting for me to start taking pictures, here's one of the scope rigged up. It's such a purdy little thing!

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#2 Steve_M_M

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Posted 01 July 2013 - 01:19 AM

Good story. We were talking about you and your e-130 at Mt. Pinos on Friday night. I mentioned focus as an issue with my e-160 from years past. Glad you got it all worked out. Here are some jewelers screw drivers for next time....

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#3 tim53

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Posted 01 July 2013 - 01:30 AM

Yeah, too bad I can't print 'em out and use them here!

Hardware store will be open tomorrow, though.

The Lumix does a nice job, but it can't go over 60 seconds and it's not so great at the higher ISO settings.

So I definitely want to hook the Canon up and see how it'll do.

-Tim.

#4 tim53

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Posted 01 July 2013 - 02:05 AM

Well rats some more.

I assume the corrector doesn't move with the focuser? If it doesn't, then the spacing between the corrector and the ccd is set by best focus, and the collimation is off (or the spacing between the primary and the corrector is off). If it does, then the spacing between the corrector and the ccd might depend on the adapter and the backfocus distance in the camera body.

I can get decent focus on the center stars, but ring nebulas at the corners.

A single 60 second exposure of M51:

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#5 tim53

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Posted 01 July 2013 - 02:10 AM

Even at this reduced scale you can see the ring nebula effect, which is worse toward the lower right of the frame. Hm... must be collimation, then?

The camera isn't real sensitive, and does poorly at high ISOs, so I should stick to star clusters.

Here's the Coathanger

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#6 tim53

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Posted 01 July 2013 - 02:15 AM

Polar alignment and tracking seem to be doing pretty well, considering. I wish I could leave it out, but I can't. Thankfully, it's light enough that I can probably just haul it in and set it on the screen porch with a jacket thrown over it for hoots.

But I'm getting sleepy. I'll be able to stay up later tomorrow night. It's still pretty warm in the house at 1:13 AM local time. Got to 102 today. Was 117 when I went through Vegas yesterday. I heard tell that it was 120 today! Honda with 176K miles on it did pretty well, but one of my front tires has a bubble in the tread now. I'm going to swap out for the spare and hope that gets me home.

Night night.

-Tim.

#7 Dave M

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Posted 01 July 2013 - 06:25 AM

it occurred to me that the diameter of the bayonet of whatever it is was at least a slip fit onto the Konica to Lumix adapter that I bought so I could use my Konica glass with the Lumix. So, I got out the trusty duct tape and made them one!

So now it works!


Could also be something flexing or not square.

#8 Chuck Hards

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Posted 01 July 2013 - 06:41 AM

Life in the "fast" lane, Tim! ;)

#9 turk123

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Posted 01 July 2013 - 07:03 AM

Here is a little adjustment

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#10 tim53

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Posted 01 July 2013 - 10:21 AM

Now that I've had a cup of coffee and my head isn't hurting so much and I'm awake, I notice that the best focus is sort of a linear trend diagonally across the scene.

I also should have downloaded a couple of the out of focus donuts I shot while figuring out the Lumix operation. It's clearly out of collimation.

No worries, though. Not big ones, anyway. I downloaded the manual somwhere and I have the cheshire eyepiece that came with the scope, so I will work on collimating it this evening.

Got to dial into a couple telecons in a bit, then I need to go help out with my wife's class this afternoon, but I do intend to get over to the hardware store for some jewelers screwdrivers and try to get that camera adapter apart, because it would be nifty to try the Canon on the 130.

Thanks for the adjusted view, Tom! I should probably spring for a decent basic version of Photoshop or something on my own laptop, because all I had to use (when that tired) was Apple Preview, which is rather lame. I've also got The Gimp, which is pretty capable, but I'm so familiar with Photoshop that I haven't quite spent the time I need to get more comfortable with the Gimp's tools.

-Tim.

#11 Chuck Hards

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Posted 01 July 2013 - 10:25 AM

Sounds like a slightly tilted imaging plane, perhaps? Something out of square?

#12 tim53

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Posted 01 July 2013 - 10:28 AM

Yes, me thinks so too.

An obvious place to start would be my duct-taped camera adapter! It might have moved or sagged enough to cause the problem. But the donuts aren't round, either. So collimation is in order as well.

-Tim.

#13 tim53

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Posted 01 July 2013 - 03:16 PM

So I got a set of jewelers screwdrivers and got the bushnell adapter off the Tak insert. It's a wedge thingy that the set screws bear against. I thought I was good to go until I discovered that the Canon adapter was about 2mm bigger on the inside than the other one. So, I got out the trusty duct tape and wrapped about 3 strips around it, put it in place, and tightened the setscrews to where it doesn't look like it'll move.

Here it is, with most of the duct tape out of sight. If I can cut metric threads with one of my lathes at home, I might machine a new adapter to go between the Tak focuser and the Canon adapter ring. But we'll see.

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#14 tim53

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Posted 01 July 2013 - 03:19 PM

And here's the camera in place. I experimented to make sure I can reach focus by looking at some clouds over a roof in the distance, and there was leeway either side of focus, so I'm good to go. Now I can go ahead and download my trial copy of Backyard EOS, and see if it runs in Windows 7 under VMWare Fusion on my Macbook Pro.

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#15 tim53

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Posted 01 July 2013 - 06:05 PM

So I was reading the F manual, and it hit me: Collimating this thing isn't rocket surgery. It might be a little more touchy than a fast newt, but it's basically the same procedure.

and the scope is engineered like a brick... ...it's well built!

Anyway, still have the collimation to do, but I think I'll wait for dark to do it while viewing a live image on the computer screen.

YES! I got Backyard EOS installed and it appears to work!

-Tim.

#16 tim53

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Posted 01 July 2013 - 06:24 PM

Well, that was easy:
Posted Image

Took less than 3 minutes to collimate (daylight). The secondary was off a tad and the primary push pull screws were all loose - no kidding. Why didn't I ever check those? :shocked:

Anyway, I'll revisit fine-tuning at night.

-Tim.

#17 Dave M

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Posted 01 July 2013 - 06:56 PM

Looking forward to seeing your results tonight.

#18 tim53

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Posted 01 July 2013 - 06:58 PM

Weird, too. It's CLEAR! We're usually getting thunderboomers around this time of the afternoon.

...it's hot, too!

-Tim.

#19 Chuck Hards

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Posted 01 July 2013 - 09:08 PM

Totally overcast up here. It moved in quickly.

#20 tim53

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Posted 01 July 2013 - 10:51 PM

I've got clouds low on the north horizon, but rest of the sky is crystal clear.

Just got polar aligned and checked out the star images visually. Seems to be pretty good, especially compared to last night! But I think I'll get the camera hooked up sooner rather than later to make sure.

-Tim.

#21 tim53

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Posted 01 July 2013 - 11:23 PM

Now I'm embarrassed again because I don't know where my images go when I take them. Yet.

My first image ever with BackyardEOS and the Canon T1i was a 60 second exposure on Deneb. No processing at all. PINPOINT STARS RIGHT TO THE CORNERS!

I'm a Cappy Hamper!

-Tim.

#22 tim53

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Posted 01 July 2013 - 11:49 PM

Here's a drastically reduced image of the Deneb region. Two minute exposure at 800 ISO. No darks or flats.

Of course, it's reduced in size, but the stars really are pinpoint to the corners!

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#23 tim53

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Posted 01 July 2013 - 11:51 PM

Boy do I feel like an idiot. That's Vega, not Deneb!

-Tim.

#24 Dave M

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Posted 01 July 2013 - 11:58 PM

That looks Tak-alicious, Nice work Tim :bow:

#25 Steve_M_M

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Posted 02 July 2013 - 12:17 AM

Fantastic image Tim. I am out tonight doing some imaging too. A bit different though as I have my 60mm f20 Goto piggybacked on my 12" LX200 with a Mallincam Extreme in the Goto. You are seeing "all the sky" and I am seeing "a teeny tiny bit of sky". Clouds are rolling in here too, so I am packing up.

I love those Taks you acquired :)






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