Sunday, October 04, 2009

 

You Must Choose…

Brothers and sisters. You must choose…a CCD camera if you intend to get into the imaging game in 21st century style. This is, I reckon, a follow-on to a recent entry, “Trying to Take Pictures.” Therein I talked about first steps in imaging in general terms equipment-wise. Now I am gonna get specific as to camera choices. Well, some camera choices. This time out we’ll be looking at astronomy-specific cameras. Real Soon Now we’ll visit the DSLR showroom.

Hokay, for the sake of argument, we’ll assume you have settled on an astro-camera as your imaging tool of choice. These imagers, also sometimes generically referred to as “cooled cameras”—though not all of them feature active cooling—or “integrating cameras,” are, unlike Digital Single Lens Reflexes, intended almost exclusively for astronomy (some have been used for takin’ pictures through microscopes as well). You will not be shootin’ holiday snaps of Aunt Lulu and her beloved poodle dog with an SBIG ST-2000. It is possible to adapt them for piggyback imaging through standard camera lenses, but when I think “CCD” what I mostly envisage is “prime focus deep sky photography.”

What’s out there? A lot. From two or three big-time manufacturers serving the amateur-astro-community, we’ve gone to at least half a dozen majors and probably at least as many minors over the last fifteen years. You’ll see I’ve mainly stuck with the makers that appeal to the decidedly plebian side of the market. I speck those of y’all dippin’ your toes into the CCD pool for the first time are gonna want to do that to the tune of 2 – 3k dollars MAX. I know I did.

There are more good cameras in all price ranges than those you’ll find below, sure, but I do note there seems to be a general tightening up of the introductory market, especially. Some of the pioneering low-end names have dried up and blown away, maybe owing in part to the recession, but maybe also due to the popularity of DSLRs in the less than 1k category. SAC imaging, for example, who started with webcams and moved on to fairly sophisticated integrating cameras, is gone. ATIK, another early entry on the low end who went on to more sophisticated products, is still around but no longer has dealers in the U.S.

Starlight Xpress

Why do I start with the UK’s Starlight Xpress? One reason is that Terry Platt’s cameras have always been innovative, doing things nobody else does and doin’ that well. It’s also because the first CCD camera I owned when I got started in solid-state imaging a decade ago was an SX. I’d looked longingly at the SBIGs, but was a wee bit skittish about spending the money their introductory camera, the ST-237, cost. Not only was the Starlight MX516 cheaper, it featured self guiding.

No, it didn’t have a separate onboard guide chip like the SBIGs; that is a proprietary feature peculiar to the Santa Barbara cameras. No doubt a guide chip would have priced the 516 out of my one-grand or so range anyhow. But the 516 (and a couple of Terry’s other cameras) had somethin’ that sounded just as good: STAR 2000.

This auto-guiding system, still used in some current SX cameras, allows the CCD chip to guide and image at (almost) the same time. It requires an interlaced-scan type CCD, and essentially guides for half a frame and images for the other half. How well did this work on my little camera and how well might it work today? Purty good. Yes, it had the effect of reducing the sensitivity of these already not overly sensitive cameras a wee bit, but was workable. Given a decent polar alignment, it guided my Ultima 8 with surprising effectiveness.

So why did I wind up cussin’ the camera most of the nights I used it? Mainly due to its tiny 500x290 pixel chip. Given that I didn’t have a go-to rig at the time, getting a DSO on the sensor was challenging at best and damned near impossible most of the time. For that reason, I sold my MX516 in 2003 to raise the funds for a SAC 7B one-shot color (webcam) imager to use on Mars during that year’s amazin’ opposition, turned to Meade and then SBIG for my deep sky imaging needs, and never looked back.

Does that mean the Starlight Xpress cameras of today are no good? Not hardly. Terry’s current line is as sophisticated as anything out there. In fact, some of the finest images I’ve seen over the last several years have been produced with the company’s large-chip cameras. Not ready for large chips? The descendent of my li’l MX516, the SXVF-M7 improves on its ancestor with a somewhat larger 752x580 chip and one-shot color, and comes at a relatively reasonable $1595.00.

Unfortunately, the company’s newer imagers use progressive scan chips, meaning STAR 2000 won’t work with them. Starlight does make a nice compact guide-camera now, though. If you really want to try STAR 2000, the company still sells some interlaced chip cams, including the SXVF-M7. One huge advantage of the SX cameras comes for users of Fastar/Hyperstar. Their small cross-section tubular cases mean you won’t be blocking light or reducing contrast when you hang ‘em on your corrector.

In addition to innovation, Mssr. Platt offers high build quality and, very important for y’all just being initiated into the CCD way of picture taking, superb support after the sale. I said I turned to Meade and SBIG for deep sky cameras, and while that’s true, I still like the Starlight gear and will for sure consider one of their products in the future.

Meade

Meade produced a line of fairly sophisticated CCD cameras in the 1990s, its “Pictors.” Most notable of their advanced features was the more expensive models’ SCSI interfaces. Back then, everybody else was stickin’ with the same old uber slow parallel/serial mess. You’d a thought the Pictors would have been a big hit—both for their features and for the fact that lotsa Meade fans like Meade badges on all their gear—and they would have been if they’d worked right. Unfortunately, the word got out that the cameras in general and that SCSI interface in particular did not work very well at all.

There things remained until a couple of years after the new century came in. To be honest with y’all, I hadn’t associated the word “Meade” with the word “CCD” in quite a while. Not until I got an email from the good folks at Anacortes Telescope and Wild Bird. They was wonderin’ if I’d like them to reserve one of Meade’s new $399.00 DSIs for me.

A little rootin’ around on the dad-blasted Internets informed me that “DSI” was the acronym for Deep Sky Imager, Meade’s new one-shot color deep sky camera. My SAC7b, humble as it was, had shown me how nice it can be to get a color picture in one frame, so I was intrigued. And almost got out my credit card. Till further reading revealed the DSI was uncooled. Uncooled? Hell, even the SAC had a Peltier cooler. Wouldn’t the Meade’s images be a mass of false stars without coolin’ to reduce thermal noise?

Not according to Meade’s ads. They said the camera used a passive cooling system (a heat sink on the back) and software that turned off as much of the camera’s electronics as possible during exposures to reduce heat-inducing noise. Now, Meade’s ad-copy writers have been known to occasionally stretch the truth, or at least gussy it up, but I was intrigued. The sample images they was showing looked fairly impressive, 400 bucks was a lot less than I’d paid for the MX516, and this one had a bigger chip (510x492) than my old camera. I figured it was time I tried deep sky CCDin’ again.

When I received my DSI, I was right impressed. The little thing was solidly built and included a 1.25-inch nosepiece and an IR filter (albeit one not in a filter carrier; it was jus’ a piece of easily broken glass). Yeah, the dadgummed USB cable was way too short. What could Meade have been thinkin’ when they decided we would be OK with a 4-foot cord? Answer: nothing. Still, a genu-wine USB 2.0 camera for this price? Did I tell y’all just how long it took my MX516 to deliver an image to the computer via its parallel interface? Long enough to make me wonder if it was time to sign up for the consarned AARP.

So, “hardware good.” How about the software? That was a different story. A CD jus’ full of stuff was delivered with the camera. Somethin’ called “Autostar Suite.” This was not just a camera control program, but a planetarium app (Meade’s hoary ol’ Epoch 2000), and a barebones image processing program, Autostar IP. Those I could dispense with since I had TheSky and Photoshop at my beck and call. All I needed off the Meade CD was Enivsage, which ran the camera. It was a monster. Not just because it did a lotta stuff: focus assistance, image stacking, image quality evaluation, time lapse photography, histogram display—quite a contrast the barebones software that came with my MX516. It was also a monster when it came to user friendliness. And I don’t mean that in a good way.

The main screen of Envisage was an absolute mess of stuff. More than one new DSI user never got it figgered out. Which is not to say it didn’t work pretty good if/when you did. Once I’d somehow managed to cipher out how to get it goin’, it did an outstanding job. While Meade has tweaked Envisage over the years, it has retained the same character: 10 pounds of spit in a 5 pound bag.

Despite Envisage’s faux pas, I cranked up my CG5 and C8 and shortly got much farther with the DSI than I ever got with the ‘516. One huge help had nothing to do with the camera: even though I was using a very early version of the Celestron CG5 firmware, the mount would almost always put my targets on the DSI’s tiny chip at about 800mm of focal length (attained with Meade’s f/3.3 focal reducer).

After just a little experimenting, I established a routine that brought me some images that pleased and still please li’l ol’ me. I’d polar align using the utility in the hand control, go-to align the scope, focus up on the last alignment star, and send the mount to the evening’s first target. If it wasn’t on the chip or nearby, I’d engage Celestron’s “Precise Go-to” function. With that turned on, the mount would go to a bright star near the target. You’d center this star in the eyepiece and hit Enter. The CG5 would then proceed to the object of choice, which would invariably be visible on the computer screen. Which impressed me quite a bit. The little cam was actually pretty sensitive—considerably moreso than my old monochrome Starlight Xpress—and would show at least a trace of even dimmer objects with just a few seconds of exposure.

I found I could go as long as 30 – 45 seconds unguided with my humble rig and still get nice, round stars in most frames. What I would do was instruct Envisage to take 30 second frames, and stack those that were of good quality (which it was able to determine automatically) into the equivalent of a longer exposure. Half an hour of which would bring back just about anything I wanted. Not only would NGC 7331, the Deerlick, for example, be detailed and showing nice color, the tiny NGC galaxies around it, the Deer, would be there shining their little hearts out. More surprisingly, close examination of the image revealed miniscule sprites of PGC galaxies in the frame.

Yep, I was very pleased with the DSI; I felt like I was finally getting some CCD results. Not that it was perfect. Even with longer, guided exposures, the images it produced were noisier than those taken with a cooled camera. There was that eensy-beensy chip, too. I like to make 8x10s of my shots, and I found the camera’s images just would not stand that much enlargement. Otherwise, though, the original color DSI was a winner, and, as I’d hoped, Meade didn’t stop there.

Shortly after the original camera’s debut, they brought out a more sensitive monochrome version, the DSI pro (which included an integral filter slide for tricolor pictures). Both these cameras are gone now, though, being phased out not long after an even more improved cam, the DSI II, hit the streets. Not only had Meade improved the camera’s noise profile, the chip had got bigger too; it was now a slightly more generous 752x582. Even better, the price for the II has sunk to the same $399.00 I paid for the original. Like the earlier camera, this one is available in one-shot-color or “Pro” monochrome versions.

Meade still wasn’t done. Just as the II was reaching its ascendency, they brought out a DSI III. The III is the most expensive model yet, now clockin’ in at $799.00 (after a couple of price reductions), but that is an incredible price considerin’ what you get, which is mainly a 1.4 megapixel 1360x1024 CCD. No, there’s still no cooling, but Meade’s engineers have continued to refine their passive cooling scheme to the point where that is much less of a concern. These two babies (a color and a Pro as before) put Meade back into the big-boy camera arena they deserted when the Pictors were cancelled, and folks are doing some incredible work with them. I’m surprised there ain’t more interest in the DSI III than there appears to be.

Orion

Maybe I know the reason for that, though. Orion, the U.S. Orion, the Telescope and Binocular Center, decided to poach on Meade’s preserve camera-wise. They began by contracting with SAC, the wee Melbourne, Florida semi-garage-outfit, which had been having some success with its first non-webcam imager, the SAC 8. The resulting camera, a color one-shot, the StarShoot, was similar to the DSI in most ways. But not all. It was cooled, being designed around a Peltier solid state heat pump that was surprisingly miserly current-wise, operating off a pair of D cells. And it came with a simplified version of Maxim DL, Maxim DL Essentials, that most folks found easier to use than the confusing Envisage.

It wasn’t all gravy, though. Despite cooling, the StarShoot’s noise profile was not that hot (or maybe too hot). And like the SAC 8, the unregulated cooler had a tendency to make the chip frost-up on humid nights. The big problem, though, turned out to be getting one. There was simply no way SAC could produce enough cameras to satisfy Orion’s customers. They’d, in fact, had a hard time making enough SAC 8s to serve their own small customer base. It’s not unusual for too much success to bring a small company down just as quickly as too little. That was just what happened with SAC. In fairly short order they were in bankruptcy.

That didn’t stop Orion, though; they just switched suppliers (I don’t know who makes their cameras now, but it may be the UK’s Atik/Artemis). Whoever makes ‘em, they did their homework, as the current models, the StarShoot II, the StarShoot III, and the StarShoot Pro are worlds better than the SAC, and, in some ways, are a considerable advance over the DSI II and III. The one-shot color II is equipped with a 752x582 chip just like the DSI II. But not only does it come with better software, the Maxim DL Essentials program and an improved Peltier cooler, it goes for an amazing $299.00 now.

Want to play in the big leagues? Try the (monochrome) StarShoot III. It sports a 1392x1040 chip and improved cooling with the addition of a fan to help disperse the Peltier’s heat, something the original StarShoot and the StarShoot II both lack. Yes, at $1499.00, it’s more costly than the comparable DSI III, but the cooling system may make that an easy pill to swallow.

Don’t like black and white, and don’t intend to fool with tricolor imaging? $1199.00 gets you a StarShoot Pro, a one-shot-color Orion with a great big chip. This 6 megapixel cam delivers 3032x2016 pictures to your computer. If you want more better gooder than that, an additional 200 Georgie Washingtons will buy you the StarShoot Pro v2.0, which boasts a substantially improved thermoelectric cooling system. It’s still not regulated, but at least features software control of the fan.

These new cameras, along with a couple of autoguiders, including a standalone model (like the old ST4 and STV from SBIG), have given Orion a leg up in the CCD race. Not only are they leavin’ Meade behind in the low-end contest, they are preparing to release a pair of cameras using Kodak’s big KAF8300 chip. Since the heavy hitters in the CCD biz tend to price cameras using this CCD sensor in the 6000 buck and up range, if Orion can do a good job and also bring their pair of cams (a color and a monochrome) in for substantially less, they may be ready to play with SBIG, Apogee, and FLI, and will have come a real long ways since the days (not long back) of their little SAC imager.

SBIG

For those of us for whom the CCD bug is not just a passin’ affliction, it usually comes down to SBIG. Oh, some of y’all who are really good at this difficult art will kick it up another notch with the Apogees and FLIs, but, honestly, no matter how advanced you get, Santa Barbara Instrument Group has a camera for you.

Their product line ranges from the 765x510 ST-402, the descendant of the pioneering ST-4, to the likes of the new 16 megapixel STX camera. The ST-402 goes for a reasonable (given its build quality) $1495. Yes, you’ll pay more for an SBIG than you will for an Orion or a Meade, but from my first use of one, a buddy’s ST-237 (a long-discontinued novice camera) I could see why.

SBIG’s build quality is very high, all the cameras have regulated coolers (set it for -10, and it stays at -10) that deliver low noise images, and the software that comes with the cameras (CCDops) is simple and easy to use and really, really works. When I want a serious picture, I pull out an (1600x1200) ST2000, which, in addition to all the other qualities common to SBIG cameras, features the aforementioned extra chip to handle guiding. With no guide scope to worry about, CCD picture takin’ is, even for me, almost easy.

If I had to choose today? If I were just embarking on the daunting but exhilarating CCD adventure? If I had 3K to spend, it would be hard not to consider a monochrome or color ST2000. But I realize most beginners don’t want to spend that much. If half that is practical, I vote for the StarShoot Pro. Still too much? The DSI III—you could do worse. Because of the inherent additional difficulty imposed by a real small imaging chip, I don’t recommend the DSI II or StarShoot II. Not only does a little chip make target finding harder, even with a good go-to, the “magnification factor” imposed by small sensors makes guiding accuracy way more critical.

None of the above your cup of tea? There are other players in the intro/mid-range CCD game: ATIK, QHY, and more. Still not sure? There is that other road to deep sky imaging satisfaction, the Digital Single Lens Reflex. But that, muchachos, is a story for another Sunday.

What’s hap-nan here? At good ol’ Chaos Manor South? Not only is the Moon full, the clouds are back. Miss Dorothy and I spent most of yesterday evening at the (annual) Bayfest where we saw two of our favorite bands, Hank Becker and the Boogie Chillun, and hometown heroes Wet Willie. A good time was had by all. Even if a stinkin’ Coors Lite did set me back 5 bucks. In other news? Your ol’ Uncle continues his assault on modern technology, and now has a Facebook page up. Check it out, but be forewarned, I am still tryin’ to figure out how it works and what exactly it is good for.

Comments:
Rod - good info

Right now ST-8ME is the same price as the ST-2000XM - would you still go with the ST-2000XM?

Bob
 
Probably so. Its chip size and pixel size do a fine job for me with everything from SCTs to my little APO refractors. Nevertheless, the ST-8 is a fine, fine camera, and now that it's more popularly priced, I'm sure lots of folks will vote for it.
 
What about an ST-2000XM ($1500, no filters) vs a StarShoot Pro V.2.0 ($1200)?
 
What about an ST-2000XM ($1500, no filters) vs a StarShoot Pro V.2.0 ($1200)?
 
If you can get an ST2000 for that price, that is a very valid choice...but the older I get, the more I like one-shot color.
 
So the ease of the OSC might outweigh the RGB effort? This would be my first CCD Imager. It's for a 10" LX200R. With the ST-200XM I'd still need to spend another good amt to purchase the wheel and filters. Guess I'm curious what you think of the SSP v.2.0? Thanks, lvoe your Cat book btw!
Scott
 
The Orion sure LOOKS and SOUNDS good, but I haven't seen enough results with it yet to say for sure. If you're like me and don't aspire to bein' the next Jack Newton or whatever, and just want some purty pics to be proud of, I think one-shot-color or a DSLR is the way to go.
 
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