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Forum: Post Your Photos! 06-26-2019, 10:37 AM  
Nature Another pass combining Ha with RGB data on the Pelican and NA
Posted By fewayne
Replies: 6
Views: 231
If you would care for advice, I would be honored. If you don't, ignore rest of message :-)

I agree that single-frame images without tracking are probably going to fall short of what you would like. At 390mm effective focal length, AstroTracer gives you only a few seconds' exposure. That's a start...so long as you can stack.

Stacking can certainly be a bit of a pain. I used Photoshop and free software for awhile, but finally bit the bullet and bought dedicated software just this week. Deep Sky Stacker is probably the most popular free program for the purpose, and works reasonably well on default settings. Siril is pretty good, but its user interface is kind of abstruse. If you have Photoshop, opening your exposures as layers, selecting them, Edit | Auto-Align Layers will register them, then you can convert to a smart object and set the object's stack mode to Median.

Focusing is HARD. Even experienced astrophotographers struggle with it. Wide open, at long focal lengths, the zone of sharp focus is miniscule, we're talking microns. So those of us who lack astro autofocusers make or buy Bahtinov masks, and magnify the Live View image of a bright star to be able to see the spikes. Usually I have to use Vega or Sirius to have enough light to focus on, and then verrrry carefully swing around to my target without disturbing the setting.

Your image proves that you can certainly achieve sharp focus! That's an amazing result for a telephoto on a tripod.
Forum: Post Your Photos! 06-25-2019, 08:05 PM  
Nature Another pass combining Ha with RGB data on the Pelican and NA
Posted By fewayne
Replies: 6
Views: 231
First, thank you. I'm pretty happy with that image.

But my friend, if I can do it, you can do it. Trust me on this one. The guys and gals on the astrophotography forum will doubtless agree, because they've been hearing and seeing all my spectacular failures for years. Dropping telescopes. Failing to get the focus right. Forgetting the bring gear. Forgetting to charge batteries! Failing to get the scope pointed at the freakin' target.

This image was done with a full-on deep-sky setup: Stellarvue 70mm astrograph, an iOptron equatorial mount, guidescope and camera, dedicated Raspberry Pi controlling the setup, and a cooled mono astro camera with electrically-driven filterwheel. All of which I am only starting to get the hang of, but while fancy gear doesn't guarantee good results, in astro it's much easier to be gear-limited than in some other realms.

If you're interested in astro, that forum is one of the best resources around. Doesn't have the population of, say, Cloudy Nights, but it is an incredibly supportive group of people, some of whom are both outstanding astrophotographers and amazingly willing to analyze errors, share their secrets, and teach.

And if you're interested in seeing some of my journey, my Zenfolio astro page has the evidence, including some of the egregious fails!
Forum: Post Your Photos! 06-23-2019, 10:09 AM  
Nature Another pass combining Ha with RGB data on the Pelican and NA
Posted By fewayne
Replies: 6
Views: 231
Here is a re-re-edit, combining some old data I acquired with my DSLR and stuff just last month off the mono/filterwheel setup. North American and Pelican Nebulae.
Forum: Pentax DSLR Discussion 10-20-2018, 08:22 PM  
DC power supply for K-5 or -7
Posted By fewayne
Replies: 4
Views: 670
Well, I suppose I could buy the adapter, cut the DC end off, and throw away the AC part. Cheap source for the plug, and I could test for the pinouts. Thanks!

---------- Post added 10-20-18 at 22:24 ----------


Poifect! The drone article has everything I need, I believe. Thanks!
Forum: Pentax DSLR Discussion 10-20-2018, 01:05 PM  
DC power supply for K-5 or -7
Posted By fewayne
Replies: 4
Views: 670
Hey all,

There was a great DIY article by a helpful fellow named Bob who figured out what Molex connector was needed for the 8.4V power input, how to wire everything up, and all the details. But the link has gone dark. Does anybody have the requisite info? I can dig up the part number for the voltage regulator, but the pinouts and connector P/N elude me. Since my astrophotography setup needs to run for hours uninterrupted, it would be delightful if I could run it off the big 12V for my mount and computer, rather than swapping LI-90s.

Thanks!
Forum: Post Your Photos! 08-24-2018, 12:34 PM  
Night Andromeda Galaxy
Posted By fewayne
Replies: 26
Views: 787
My iOptron CEM25P mount, like many others, can talk to a computer via the serial port in its hand controller and a USB-to-serial converter box. I selected KStars/Ekos as my astronomical software because I wanted to run a Raspberry Pi in the field and not depend on my laptop's batteries. With no other hardware than that, I can use Ekos's polar-alignment routine and usually nail it within a few seconds of arc within ten minutes or so. You simply point the scope roughly at Polaris, and the s/w shoots a series of three images, does plate solving to figure out exactly what's in the picture, and then does the math to determine where the polar axis has to be pointing in order to yield those particular results.

It sounds complicated but in practice it's really simple. I had to download and install some of the plate-solve index files, but other than that it was pretty turnkey and the actual process is really pretty simple. iOptrons have a pretty dang good polar scope but this gets me to MUCH better accuracy.

I use the guidescope and guide camera for this since the lower magnification does not necessitate as many index images, but if you download the extra indices, it works perfectly well with your main imaging scope too.
Forum: Pentax Forums Giveaways 07-30-2018, 04:00 PM  
July Pentax K-1 Giveaway: Raffle Thread 4, 23:00 UTC, July 30, 2018
Posted By fewayne
Replies: 68
Views: 4,037
Ooooo me please!
Forum: Post Your Photos! 07-30-2018, 01:49 PM  
Nature So, She Sez, The Liver's The Best Part, And I Sez...
Posted By fewayne
Replies: 5
Views: 197
IK, R? One of the local power plants has a falcon nesting box which has been occupied every year for the past ten, IIRC. And watching those peregrine chicks go from fluffballs to gawky cartoons to mad-flapping crufty-looking fledglings has been just a stitch. Then one day they turn into 200-MPH Death From Above predators. Hmm. Maybe I should be watching my children a little more carefully.

Probably nothing on the livestream now, they've all flown but some of the chicks are still hanging around, hoping Mom will come back and feed them. Also very much like teenagers, that.

Wait, I'm wrong, at least as I typed this one of the chicks was visible on the Livestream cam, just snoozin' away.

MGE Peregrine Falcons - Madison Gas and Electric. - Madison, Wisconsin
Forum: Post Your Photos! 07-30-2018, 01:41 PM  
Night Great Nebula in Orio
Posted By fewayne
Replies: 9
Views: 379
I think it's particularly funny that, given the facedesk fail of not getting the image uploaded, I also irrevocably committed the title "Orio" to posterity.
Forum: Post Your Photos! 07-30-2018, 11:30 AM  
Night NGC 7000 and IC 5070, aka North American and Pelican Nebulae
Posted By fewayne
Replies: 2
Views: 309
Wow, thanks! If you really want a bottomless time-sink of jaw-dropping astro imagery, just drop in on astrobin.com and click around. For example, search for "North American" on their home page and marvel at what the astrophotographers who know what they're doing have done with this deep-sky object.

Figuring everything out and getting it set up for a night of imaging...I tend to think "Sheesh, how hard could it be, I can do it." But I've served a pretty intense apprenticeship, and I think I undervalue just how much I've learned in the past 2-3 years. However, the actual doing is mostly a matter of swatting mosquitoes in the summer and shivering in the winter, while the shutter goes "click" and the mount makes those contended little grunting noises as the autoguiding software nudges it about.

Processing, though. That's another story. However you'd be amazed at what you can accomplish with anywhere between 10 and 50 time exposures -- say, 15 seconds for a wide-angle lens -- of the night sky. The elements of stacking and processing a photo like that can really, honestly, for realz learned in an evening. Perfecting it takes a lifetime, of course. Or so I assume!

Lonelyspeck.com has some great Milky Way tutorials, including shooting it with your cell phone!

---------- Post added 07-30-18 at 14:07 ----------

Just tweaked the processing on this -- did Levels to set the black point a little higher, making the shadows darker, and then Stamp Visible, duplicate the layer, and set blend mode to Soft Light at 27% opacity. Much more dramatic image, without IMHO looking cheesily garish. Maybe a teeny bit of the nebulosity lost off the dark end, which is acceptable.

Forum: Post Your Photos! 07-29-2018, 06:13 PM  
Nature Pensive Fox Kit
Posted By fewayne
Replies: 3
Views: 315
Thanks from an old Osceola boy!
Forum: Post Your Photos! 07-29-2018, 06:12 PM  
Night Andromeda Galaxy
Posted By fewayne
Replies: 26
Views: 787
Haha, Shinigami, you speak RANK ASTROPHOTOGRAPHY HERESY! But thanks.

I just looked -- my Tammie is indeed the 55BB. I'd had it for maybe 36 hours when I dropped it on a tile floor, so I'll never know how sharp it COULD have been! But it has done some really nice work for me, assuming that I have the time to get it focused exactly right. I'd like to try it out again using my Bahtinov mask for really critical star-focusing sometime. Now that I have a Stellarvue, it's hard to put known-inferior optics on the mount and use up good imaging time, though!

The Andromeda Galaxy is actually huge, covering something like 3 degrees of sky. In fact it's reasonably easy to see with the naked eye if you know where to look and have a modestly dark sky. You won't see this, of course, but especially if you avert your gaze just a smidgen you can definitely pick out a fuzzy patch up there.

I too have at least one image that looks kinda like an oversize core with maybe a little smudgy stuff around it. That was three years and a lot of reading and practice ago. :-)
Forum: Post Your Photos! 07-29-2018, 06:01 PM  
Night Milky Way and Meteors
Posted By fewayne
Replies: 17
Views: 523
Despair not! How I Photograph the Milky Way from Light-Polluted Skies of Singapore | Justin Ng Photo

Sure, it's harder, but it's achievable!

---------- Post added 07-29-18 at 20:04 ----------

Oh, and I'll tell you a secret: Look at the horizon line on the second one. Those "hills" in the background bear an uncanny resemblance in shape to the stuff in the foregr--hey, wait a minute!

I cannot tell a lie, that was a stitching fail. Photoshop's auto-align didn't work and so I had to align them manually. Was looking at the stars, didn't notice that I've boogered the horizon...
Forum: Post Your Photos! 07-29-2018, 05:31 PM  
Night Stars Go Zoom!
Posted By fewayne
Replies: 9
Views: 359
Sometimes sharing your fails can be good too. Here, I was using an iOptron SkyTracker mount to shoot the Horsehead and Flame Nebulae with my Tamron. That's pushing the limits of that mount pretty hard to begin with, but this frame shows an added challenge: The batteries died partway through the exposure (which was likely around a minute, the EXIF data don't include the exposure time). So the dim nebulae are relatively sharp, but when the apparent sidereal motion took off, the stars were bright enough to expose long trails.

I swear on my honor as a Pentaxian that this is a single exposure, NOT a double exposure or composite of any kind.

Warp speed, Mr. Sulu!

Forum: Photographic Technique 07-29-2018, 05:23 PM  
Astro Aperture requirements using astrotracer (milkyway photos)
Posted By fewayne
Replies: 13
Views: 1,384
I'm +1-ing IO on one of their early points too: It's much more important to get out there and get shooting and processing, rather than waiting till the One True Lens. Processing matters more in astro than in any other photographic discipline I have encountered, and the only way to get good at it is to do it. A lot of it. (Much more of it, apparently, in my case!) It's hardly unusual for me to spend several hours on a single image, throw that out, and start over. Bracken's Deep-Sky Imaging Primer is just excellent if you want to read up. The Brits swear by Making Every Photon Count, I haven't read that one.
Forum: Photographic Technique 07-29-2018, 05:13 PM  
Low-Light Astrophotography tips - a short tutorial
Posted By fewayne
Replies: 12
Views: 1,099
I heartily agree with GPM here, just learning the techniques of astrophoto imaging and processing is enough for plenty of hours of fun. Some of it with cuss words.

Stacking has become so simple these days that IMHO there's hardly a reason not to do it. I still stack a lot of my deep-sky stuff taken through my telescope in bog-standard Photoshop -- no special software or complicated techniques needed.

Also agree that this is Quite The Image, especially for one shot taken in high light pollution! I've found that by getting lots of integration time I can get around LP, but it's SO MUCH EASIER if you can get away from it!
Forum: Pentax K-5 07-29-2018, 04:58 PM  
K5 & Pentax GPS Module O-GPS1
Posted By fewayne
Replies: 6
Views: 8,004
I got my K-5iis pretty shortly after they came out, and the O-GPS1 certainly works with it (several images in my Astrophotography gallery if you like). I have used it with lenses up to 500mm, so I think the Sigma would do just fine. Mind you, you have to reposition the camera pretty often if you're going to stack, unlike with a German equatorial mount or a tracker like the iOptron. I sometimes struggle getting the "precise calibration" to take, but I've never had to give up. And the keeper ratio is lower too. But it's sure effective, and hella easier than packing one of those along!
Forum: Post Your Photos! 07-29-2018, 02:56 PM  
Nature Pensive Fox Kit
Posted By fewayne
Replies: 3
Views: 315
We had a fox dig a den right on one of the heavily-traveled main routes through campus, and the kits provided enormous entertainment for students and staff. I've seen Madison Metro bus drivers play "Make Way for Ducklings" as the mom and 5 kits crossed in front of their buses, and their playtime was pretty much joy distilled -- racing about, pouncing, wrestling, practicing being predators.

I caught this one in a rare moment of stillness, which was good as the Tammie is a slow lens and it was well into the evening.



---------- Post added 07-29-18 at 17:00 ----------

Mom and two of the kits crossing Linden Drive. Or, more like just hanging out in Linden Drive, really.

Forum: Post Your Photos! 07-29-2018, 02:48 PM  
Night Andromeda Galaxy
Posted By fewayne
Replies: 26
Views: 787
Thank you. Astrophotographers tend to be technical perfectionists -- after all there's not much posing or creative lighting to do! And so when I see flaws in one of my images, it's hard to appreciate the good bits. I need to learn to do more of that. These objects are just beautiful, although to the naked eye (or even through a quite large telescope) they're just slightly fuzzy patches. So to an even greater extent than most photography, the photographer's vision and technique is what makes the image. There's no pretense of journalistic objectivity!
Forum: Post Your Photos! 07-29-2018, 02:43 PM  
Night NGC 7000 and IC 5070, aka North American and Pelican Nebulae
Posted By fewayne
Replies: 2
Views: 309
Starting to get autoguiding figured out. This is data from two separate nights of imaging, about 70 individual 180-second frames stacked and processed in Photoshop. The telescope is more or less a dedicated APS-C astrograph, 480mm focal length but with the flattener/reducer in play it's more like 362mm. This is at least the third time I've processed this image since I shot the frames during the new moon earlier this month, and I don't think I'm done yet. The stars are still too big and garish, there's no color in them, and the nebula could have a subtler tonal range, I think. Still, I'm learning. Comedy is easy. Astro is hard.

Forum: Post Your Photos! 07-29-2018, 02:19 PM  
Nature So, She Sez, The Liver's The Best Part, And I Sez...
Posted By fewayne
Replies: 5
Views: 197
For a couple of years a pair of red-tailed hawks nested in the white pines across the street from my office. Watching the chicks grow up was hilarious.



---------- Post added 07-29-18 at 16:25 ----------

One of the same chicks, several weeks earlier. They grow up gorgeous, but there's that fuzzy infant stage and then the awkward-teenager one...



---------- Post added 07-29-18 at 16:30 ----------

I was gobsmacked to discover this redtail calmly disassembling a squirrel next to a busy intersection of sidewalks near Ag Hall and Microbiology on the U of WI campus where I work. She did not seem to care a solitary bit that some human was going click near her. Note the strong "ring" bokeh characteristic of mirror lenses; hardly super-aesthetic, but for verisimilitude I didn't smear it with Gauss blur or some such. Kicked myself most of the way home when I filled up my SD card shooting at this and then missed the money shot when she picked up the remains of the carcass, spread those magnificent wings, and took off. GAAA!

Forum: Post Your Photos! 07-29-2018, 01:42 PM  
Night Blood Moon Lunar Eclipse, 2015
Posted By fewayne
Replies: 1
Views: 170
This was a 15-second exposure with the O-GPS1 in Astrotracer mode, which is about all you can get out of it at 500mm! Still, it's pretty impressive that Pentax lets you get this kind of thing with nothing more than your camera (if it's a K-3ii or newer) and a tripod. Yes, I get better astrophotos out of my thousand-dollar telescope and thousand-dollar German equatorial mount, but (1) that's $2K blown, and (2) that rig, with 12V battery, mount, counterweight, and tripod (2" diameter legs) weighs about 75 pounds. I can put the O-GPS1 in my pocket and hardly know it's there.

Forum: Post Your Photos! 07-29-2018, 01:22 PM  
Nature Composite 2017 Solar Eclipse with Corona and Prominences
Posted By fewayne
Replies: 0
Views: 188
This is a "poor man's HDR" composite, auto-aligned in Photoshop and then mask-painted to reveal individual layer details in the corona and the solar prominences (!!!).

Astrophotographers talk about "lucky imaging" as a technique, where you shoot hundreds of video frames and let software pick out the best ones. This was geospatially lucky imaging; we judged Nebraska to be the closest point of totality with a decent probability of good weather.

Except, as many who tried know, there were widespread clouds and storms on the day of the eclipse. I was almost beside myself trying to decide whether to stick to our location in the tiny, quintessentially American town of Tecumseh or jump in the car and try to chase holes in the clouds. My wife all but slapped me and told me to settle down. And I bear witness, she was absolutely right, or else she's even more of a powerful goddess than her children and husband believe (which is going some, believe me!).

It was wild -- the clouds parted JUST around totality and let us get a glimpse. Plenty of thin high clouds in the way, but we got all the great effects -- sunset all around the horizon, evening birds singing, and completely eerie light. Then it went solid cloud again.



---------- Post added 07-29-18 at 15:29 ----------

Proof that my family loves me: They actually turned around AWAY FROM THE ECLIPSE so that I could shoot this flash/available-light composite. People are masked in from the frame with flash, everything else is from one of the available-light frame taken just beforehand. Note the sunset effect on the horizon and the "diamond ring" on the sun -- as well as all the clouds. So lucky to have been able to witness this!



---------- Post added 07-29-18 at 15:31 ----------

I should note that this is actually a THREE-image composite -- that ring around the sun is from clumsily masking in a separately-exposed image of the partially-eclipsed sun. Need to go back and fix that!
Forum: Post Your Photos! 07-29-2018, 01:12 PM  
Night Milky Way and Meteors
Posted By fewayne
Replies: 17
Views: 523
I was EXTREMELY lucky, in that I do Ski Patrol with a wonderful person whose husband is also a gem. The two of them have just retired from nursing careers and spent decades saving for a place up North, which is gorgeous. And when she heard we were going to be traveling up there, she just gave me the key. Lucky hardly begins to cover it!

We live ourselves in a dark-red zone in the darksitefinder.com map; this was one of the first chances I've gotten to do astro someplace that's truly dark. Even so, you can see the light pollution from the bustling megalopolis of Gordon, WI (pop. 636 in 2010, down 1.4% from 2000).
Forum: Post Your Photos! 07-29-2018, 01:05 PM  
Landscape Stormy sunrise, Badwater, Death Valley
Posted By fewayne
Replies: 23
Views: 831
Oh, very nice. Wonderful color without being (IMHO) over the top.
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