nwastro

[nwastro]

Hi, I'm also planning to buy a 2nd hand SXD, but I do not understand Why there is a declination jump? It's because of incorrect polar alignment? I'll use the mount but without autoguiding for astrophotograhpy, is it possible? I heard from my friends that vixen mount is designed with excellent techniques and accuracy, the jump is a mechanical problem or software/ starbook problem?

It is a problem with how the motors are being controlled by the motor board or the software. If you take an SXW/SXD with a Starbook, and remove the cover to access the gears (be careful here), and then turn the mount on so that tracking is active, you will notice that the Dec gears are actually being engaged. The gears themselves will vibrate as it tracks. Not entirely sure if it is the electronics board, or the software telling the electronics what to do, but the Dec motors are being told to do things while tracking, which is not what you want when trying to photograph things. The  amount of jump I saw in my measurements was on the order of 20 arc seconds if my memory is still correct. It wasn't periodic either. This was measured using guiding with signals to the Starbook turned off just to see the drift. Normal drift will still affect the location of star in Dec, but it shouldn't jump that much on the order of 1-2 seconds when it was smoothly drifting in much smaller increments before and after the jump.

If I had to make any sort of guess, the motors were being driven back and forth rapidly within the backlash of the gears. But occasionally it'd get through the backlash and cause the jump.  

After installing the NexSXD board, the Dec motor is no longer being driven during tracking (no noise from the Dec motor, no vibration in the gears). The mount itself is also worlds quieter, with no sign of the Dec jump while tracking.

Honestly, while this mount is a bit of a hidden gem, I can only really recommend it with a NexSXD/SXW board, which last I checked was in spotty supply. I wound up with both an SXD and an SXW in my possession for a period of time, and they both had roughly the same amount of PE (happy with the smoothness of the PE though), and they both exhibited the Dec jump with the Starbook driving it. And the PE isn't much better than stuff like the Atlas or Sirius mounts, it is just smoother. So Unguided may do well, but you are still going to be limited on the length of exposures you can make in a very similar way. But in my case, where I wanted it as a refactor mount that could do guided AP that was accurate enough that it "just worked", it is totally worth the money I spent. The competition in this space (Losmandy, AP) are more expensive, and even better built, but tend to also be heavier (CW included). This for me was a nice compromise in price, tracking quality (after the NexSXD board), and portability.

[nwastro]

Some shots of that camping battery.

[nwastro]

This is the power station I've built and been using for 4 years for Astrophotography.

As electronic devices become a bigger part of our lives, they are even making their way into the gear we take out into the wilderness. Astrophotography going digital has gotten to the point where it is normal to use a laptop in the field for multiple nights. Finding ways to keep electronics powered off the grid is becoming a blooming market, with companies like GoalZero carving out a niche for complete kits at premium prices.

For many though who need as much power as possible, as cheaply as possible, doing it yourself is an option. This is something I did before the rise of solar recharging options a few years ago, building a >100Ah 12V battery. With fuses, monitoring of battery state, and 4 12V cigarette lighter outlets, it was possible to keep my USB gadgets powered while also powering a laptop and astrophotography gear for 4-8 days at a dark site.

[nwastro]

Final version of the North American Nebula shot. There's still plenty of noise to fight, but there's also plenty of detail here too. Next time I visit this area, I should get a lot more integration time, and work with a camera that can show more Hydrogen-alpha.

Mount: Vixen SXD w/NexSXD

Camera: Canon Digital Rebel XS

Lens: EF 200mm F2.8 II 

Exposure: 33 x 5min @ ISO1600

[nwastro]

Review: TMB92SS

Thomas M. Back passed away suddenly in 2007, but he left behind some of his last telescope designs with Astronomics. Specifically, the Signature Series line still being sold by Astronomics today. As of the time I wrote this, there was still a wait list to get one. I will say it is my favorite little refractor, replacing a trusty Orion 80ED I’ve been using for the last 6 years.

The TMB92SS itself is designed with an eye towards being an imaging telescope. The end result is a short, dense telescope with a fast focal ratio that makes it easy to travel with. The focuser itself is from Starlight Instruments, which is expecting you to use some fairly heavy cameras. In short, this thing is built like a tank, and it shows. About the only thing that seems out of place is the lens shade. It slides back for travel, and only uses felt to hold it in place, so there is a bit of droop due to slack in the tolerances.It hurts the perception of quality that the rest of the telescope exudes.

Visual Quality & Focus

One issue when imaging is that your goal is to find critical focus with the telescope for imaging. When working visually, it is a little more forgiving, but since the scope is fairly fast, fine focusing is still a help here. The micro focuser, like all Feathertouch models I’ve used in the past, does an excellent job here. It can carry a good amount of weight without making it any more difficult to move the draw tube, making focusing a smooth experience, imaging or not.

Visually, the telescope is very sharp. Even when using some of my shortest focal length eyepieces, stars remained nice and tight points rather than airy disks. It’s hard to describe just how nice it is to have a telescope that does as good a job of keeping the light well focused as this one does. Yes, and 80ED can give you good views, but if it isn’t able to keep the image sharp under magnification, you lose detail. This scope has given me the best views I’ve seen of any telescope under 6”, although with the footnote that I haven’t used any of the truly cream-of-the-crop telescopes from Takahashi or Astro-Physics for any real length of time to compare. It is a definite step up from the more budget-minded telescopes out there. With optics this good, I’m tempted by the idea of binoviewers, if it wasn’t going to be horrifically expensive to double up on my existing eyepieces.

Since this is a triplet, one of the features is the lack of false color. While you can find doublets that control color very well, there is a limit to what they can do, especially in the budget category. With my 80ED, I had to fight false color pretty hard when imaging. This shot in particular, was heavily processed to try to remove false color, of which there was plenty. Another shot shows false color despite processing. Visually, the 80ED would show a little false color on some targets, making it a little harder to determine a star’s color at times. The TMB92SS in its place, showed zero false color visually. So far, it looks like the design controls false color very well.

Caveat

I have yet to actually do some serious imaging with this particular scope, and have only used it visually at this point. Even so, it is one of the sharpest refractors I’ve used. If I was using it for visual only, I probably wouldn’t plunk down the money on it unless it was my main visual telescope that I travelled with. I do plan to attempt some imaging of M42 (Orion Nebula) during the winter in order to get an idea of how well the scope itself performs imaging-wise.

[nwastro]

This is the result of a test shot I made a while back to do some imaging while testing out my mount. I may need to do a little more processing, but it turned out better than expected. The goal here was to make sure the tracking and autoguiding worked with a side-by-side mounting plate that held the Canon  lens as well as an Orion 80ED used for guiding. 

Mount: Vixen SXD w/NexSXD

Camera: Canon Digital Rebel XS

Lens: EF 200mm F2.8 II 

Exposure: 33 x 5min @ ISO1600

[nwastro]

Happy New Year

Today marks the start of 2014. May you visit dark skies, and see amazing things this year.

2017 Solar Eclipse

It is worth mentioning the 2017 Solar Eclipse, even though it is still 3 years out. This is a rare opportunity for folks in the Pacific Northwest to see a total eclipse without too much travel involved to do so, as the path of totality will pass through northern Oregon and southern Idaho before moving into Wyoming. 

2014 Table Mountain Star Party

It looks like the 2014 Table Mountain Star Party will be held at Eden Valley Guest Ranch again this year. The original site suffered major fire damage, and the Forest Service is still evaluating the condition of the area around Lion Rock. 

[nwastro]

Missing a fair amount of red, thanks to the stock IR filter present in the camera. The amazing thing is that the central star made it through processing.

Mount: LX200ACF

Camera: Canon Digital Rebel XSi

Lens: LX200ACF @ 1250mm

Exposure: 10 x 20 sec

[nwastro]

Review: Meade PST and Lunt Zoom Eyepiece

Part of my planning for the Venus transit in 2012 was to look at solar observing gear to watch the transit. One of these pieces of gear that I picked up was a Meade PST. While I was clouded in for the transit itself, I did get a chance to do some solar observing around the event with an active Sun providing a good show with this little scope.

The scope itself is meant to be portable, and easily useable by the beginner. So it includes a solar finder built into the scope, and threading on the base to mount onto a camera tripod. With the light weight, a decent camera tripod is really all you need to observe the Sun with.

Once setup, I was greeted with views of the Sun you simply can’t get any other way visually. Hydrogen-alpha scopes can show you details of the Sun’s atmosphere such as flares and prominences. However, I found that focus was difficult to achieve and things never really came into sharp relief, as if it was just out of reach. This is because at this price point, the filter cannot narrow down the light enough to get the level of detail a larger scope with a more restrictive filter can provide.

Still, worth every penny to see the Sun with your own two eyes like this.

Lunt Zoom Eyepiece

I picked up Lunt’s Zoom eyepiece to go with this scope as I didn’t have a zoom eyepiece in my collection yet. This particular eyepiece is pretty standard. Nothing wrong with it, nothing really stellar about it either. It does have the distinction of being one of the cheapest zoom pieces currently available.

Final Conclusion: Positive, But…

I should say up front that I do recommend this for folks looking to get into solar observing, and wanting to give hydrogen-alpha observing a go, but may not be 100% committed to the expense that hydrogen-alpha demands. They hold their value on the used market well, to boot.

If you are like me though, and want to see as much detail as you can in the corona of the Sun, then it isn’t quite enough. Larger solar scopes grow exponentially more expensive though, and do not make for a great first purchase. Once you do step up, there is a lot of debate between Meade and Lunt, which I myself haven’t waded into yet.

[nwastro]

Fully processed and tweaked to extract as much color as I could without introducing too much skyglow. You can see the mix of stars quite clearly.

The downside is that through being slightly out of focus, mis-collimation, or just sheer light pollution (or all three), this shot actually shows much fewer stars than are in the globular cluster.

Mount: LX200ACF

Camera: Canon Digital Rebel XSi

Lens: LX200ACF @ 2500mm

Exposure: 13 x 24 sec

[nwastro]

Review: Orion Mini-Guider Kit

Finding a good autoguiding setup for beginners, or someone who just wants a kit that works with their refactor has been a gap in the market for a while. Orion has taken the opportunity to bring out a budget-minded kit that fills this gap better than I could have expected.

Performance

The goal with autoguiding is simply to help the mount track as accurately as possible. The simpler the setup can be, the better, to avoid the usual problems like flex. This setup makes a very simple, light configuration that helps minimize these variables without having to put a lot of thought into it.

In terms of performance: guiding a 600mm refractor, I was able to achieve under 1.5 arcseconds p-p error using the kit, hooked up to the free PHD Guiding, with the default settings, on a Mac. So not only does it do a good job out of the box, but PHD’s support for the QHY5/SSAG makes it possible to run this on Apple hardware without a copy of Windows, which is a plus.

It’s hard to say a whole lot more than this. It does what it sets out to do with little fuss, and it works.

Where it Falls Short

It’s hard to be terribly negative towards this package, because of how good it is at what it is designed to be. It still has a couple of drawbacks to be aware of though.

Despite being small, the design does mean that most of the time, it will be mounted off-center on your imaging telescope. This makes balance harder to get right, and you will pretty much have to accept that you won’t be in perfect balance on your mount. It is possible to work around this, but it becomes a kit-bash of parts rather than a nice kit at that point.

Focusing with this kit is somewhat tedious. The focus ring included does allow you to reproduce focus in the future, but you will need to adjust again every so often. When you do, it will take a little time to manually slip the camera back and forth until you reach focus. The upside here is that Orion now offers a version of the package with a helical focuser, which improves this situation.

One last small thing to mention is that because it uses a small 50mm scope to track the star with a short focal length, it is limited in what type of telescopes you can guide with it. It just isn’t designed to guide something like a large SCT. I don’t personally see this as much of a drawback, as a beginner shouldn’t be starting with an SCT to image, and someone who is imaging with an SCT should be experienced enough to have the knowledge to work through the issues of guiding with a heavier setup.

Closing Thoughts

Put simply, this is a product that has been created to fill a real desire of the amateur astronomy crowd. It succeeds at doing that, and Orion has continued to improve it. You can still buy this particular package as their budget-minded model, with a more expensive version with the helical focuser available. My own personal recommendation is to spend the extra on the focuser if possible, as it will make things easier.

[nwastro]

This was an image taken awhile back that was originally a last-ditch effort to make it into a bright image contest on time. Unfortunately, it was too late in the month, and my target was hidden in the lunar shadow.

The image itself turned out to still be fairly interesting, and reveal a fair amount of detail in the craters in the southern hemisphere of the moon's surface.

Mount: LX200ACF

Camera: Digital Rebel XSi

Lens: LX200ACF @ 2500mm

Exposure: ???

[nwastro]

First attempt at guided photography. With a bit of patience, I was able to setup the main scope to guide well enough that I was able to get 2 minute exposures off a rough polar alignment without losing any of the exposures.

Doesn't really reveal much more detail since I am still only capturing about 40 minutes worth of actual exposure time, but it required a lot less processing to get this level of detail. I am actually having more problems with noise in this shot and discoloration in saturated stars than I am with fighting dim stars.

Mount: LX200ACF

Camera: Canon Digital Rebel XSi

Lens: Orion 80ED @ 480mm

Exposure: 20 x 2min @ ISO1600

[nwastro]

My first real attempt at photography with galaxies. It is not a great shot objectively speaking, but it isn't terrible for a first attempt. I've managed to capture some detail, but the big problem here is I just don't have the resolution happening, and I didn't spend enough time figuring out what the cause was (tracking, stacking, seeing, etc). 

Kept around more as an example of my early attempts more than anything else.

Mount: Celestron CGE

Camera: Canon Digital Rebel XSi

Lens: Orion 80ED @ 480mm

Exposure: ???

[nwastro]

This is a lunar mosaic I took fairly early on. The mosaic is 7 different shots taken very close to the full moon. 

The processing here was to saturate the shot until colors of the regolith itself started to appear, without becoming too saturated. Here you can start to see that instead of just a white moon, there is variety in color across the surface.

The second shot is a full-size shot, but is a bit less saturated, making the colors more muted. 

Mount: LX200ACF

Camera: Canon Digital Rebel XSi

Lens: 10" LX200ACF @ 2500mm

Exposure: 1/80 sec @ ISO100

[nwastro]

This guy felt the need to investigate my telescope when I was doing planetary photography. Lucky he didn't get to aggressive, but I have had to shoo one raccoon who was just too curious about the noise being produced by the telescope.

[nwastro]

These both were part of an experiment with an ETX125 to do a little bit of planetary photography. A mixture of a few different things made the results less than stellar. But I managed to capture the red spot with both shots. Somewhat lucky there.

Mount: ETX-125PE

Camera: Meade LPI

Lens: ETX-125 @ 1900mm and 2500mm respectively

Exposure: 80x and 120x frames respectively