Orion Nebula revisited

[Mac]

I tried to get a better capture of the Orion Nebula again last night. It was much colder than the night before when I got my first ever DSO photo and there was a lot of dew.

I first tried with my 6" SCT and could hardly see it in the eyepiece so I never bothered to attach my camera. So I switched to the 400mm zoom lens at F5 and could see it very well.

I am thinking about returning the 6" SCT and look for something better, I am not sure as I am disappointed in its performance relative to a DSLR zoom lens. While using the zoom lens pointed almost straight up at the Pleiades, it would not stay in place and sliding down.

After about an hour I was ready to get back in the house as I didn't bring warmer clothes than a hoody.

[Hankmeister3]

Thank you for sharing. Is this a guided or unguided astro-image capture? What was the exposure time and ISO speed you used?

Telephotos can be so hard to focus sometimes because of the extremely small image sizes involved. It looks like your focus was pretty close to being perfect. But if you ever want to be sure about your focus buy a relatively inexpensive Bahtinov focus mask of the appropriate size that will fit over the end of you telephoto (you can also buy one for you 6-inch SCT) which are very easy to use and they yield spot-on focus. But I think you did a very nice job of capturing M42 with a DSLR camera and telephoto.

Also, when was the last time you collimated your Celestron SCT? In view of the image you captured with your telephoto it seems to me you should have at least gotten a pretty decent image of M42 … or I may be misapprehending something here.

[Don Quixote]

This is very nice Mac.
I hear you on the tele slipping when pointed up.
My nikon does this also. I have a AF-S 18-300 G ED. It is heavy and tends to slip. I put some blue painter's tape around it when I am pointing up with the zoom out. It actually does the same thing when pointing down in the zoom is in.

[Jockinireland]

That's a nice image, well done. I d not give up on the sct yet. You should have got something with it. Let's see if we can't help you work it out.

Is it possible your sct was fogged with dew? That may be why you could see nothing. There are wrap round dew shields which help some. Or a a dew heater (what I use on my 8" sct). If need be and you have power a low heat hair drier carefully applied will clear it.

Apologies if you've already gone through all that but give us more information and I'm sure that some of the smart guys on here can help you get an image from the sct.

[Mac]

Thank you for sharing. Is this a guided or unguided astro-image capture? What was the exposure time and ISO speed you used?

Telephotos can be so hard to focus sometimes because of the extremely small image sizes involved. It looks like your focus was pretty close to being perfect. But if you ever want to be sure about your focus buy a relatively inexpensive Bahtinov focus mask of the appropriate size that will fit over the end of you telephoto (you can also buy one for you 6-inch SCT) which are very easy to use and they yield spot-on focus. But I think you did a very nice job of capturing M42 with a DSLR camera and telephoto.

Also, when was the last time you collimated your Celestron SCT? In view of the image you captured with your telephoto it seems to me you should have at least gotten a pretty decent image of M42 … or I may be misapprehending something here.

Thank you Hankmeister.

This was on an unguided Celestron AVX mount.

It was 30 seconds at 400mm f/6.3 iso160 Thought it was F5 but this lens is 6.3 at max zoom.

Focusing is fairly easy zooming way in with the LCD screen on the DSLR for the smallest point on a star at center screen. I took a few at higher iso but the focus was not as sharp as this one.

The Celestron CST is brand new and I posted some images from it in the Lunar images section. It is very sharp in the eyepiece but that doesn't come out as well in a photo. I have not collimated it and hadn't had enough experience to know how or if it needed.

I am going to return the 6" SCT and look for a shorter focal length scope and as fast as my wallet will allow. This SCT is really only good for the solar system and at F10 needs much more exposure time.

I would like to do more DSO imaging and what would be a good next target to try and image with the equipment I have?

[Mac]

This is very nice Mac.
I hear you on the tele slipping when pointed up.
My nikon does this also. I have a AF-S 18-300 G ED. It is heavy and tends to slip. I put some blue painter's tape around it when I am pointing up with the zoom out. It actually does the same thing when pointing down in the zoom is in.

Thanks Don. I never experienced that before and it didn't slip until about 30-40 minutes in the shoot. I think the cold is the culprit.

This is a Tamron 18-400mm and while not light, yours is a heavier lens as I have used one.

[Mac]

That's a nice image, well done. I d not give up on the sct yet. You should have got something with it. Let's see if we can't help you work it out.

Is it possible your sct was fogged with dew? That may be why you could see nothing. There are wrap round dew shields which help some. Or a a dew heater (what I use on my 8" sct). If need be and you have power a low heat hair drier carefully applied will clear it.

Apologies if you've already gone through all that but give us more information and I'm sure that some of the smart guys on here can help you get an image from the sct.

There was no dew as it was covered under a blanket before I started. That was the first thing I checked because as a newbie, that hit me the first night out here in Ohio when is was literally dripping. Maybe I was getting impatient trying to get it aligned on M42 and couldn't see anything except the brightest of stars in the belt. It takes about 2 minutes to switch the scope and DSLR and my first shot it was loud and proud in the LCD screen.

This was part of their bundle mount and scope. We are trying to come to a value for credit on the return of just the SCT.

[Jockinireland]

That's a nice image, well done. I d not give up on the sct yet. You should have got something with it. Let's see if we can't help you work it out.

Is it possible your sct was fogged with dew? That may be why you could see nothing. There are wrap round dew shields which help some. Or a a dew heater (what I use on my 8" sct). If need be and you have power a low heat hair drier carefully applied will clear it.

Apologies if you've already gone through all that but give us more information and I'm sure that some of the smart guys on here can help you get an image from the sct.

There was no dew as it was covered under a blanket before I started. That was the first thing I checked because as a newbie, that hit me the first night out here in Ohio when is was literally dripping. Maybe I was getting impatient trying to get it aligned on M42 and couldn't see anything except the brightest of stars in the belt. It takes about 2 minutes to switch the scope and DSLR and my first shot it was loud and proud in the LCD screen.

This was part of their bundle mount and scope. We are trying to come to a value for credit on the return of just the SCT.

OK, well I hope you get something sorted out with the dealer. Good luck and I look forward to seeing your images as you progress. It's a great hobby and this is a great place to get help and advice.

[Mac]

That's a nice image, well done. I d not give up on the sct yet. You should have got something with it. Let's see if we can't help you work it out.

Is it possible your sct was fogged with dew? That may be why you could see nothing. There are wrap round dew shields which help some. Or a a dew heater (what I use on my 8" sct). If need be and you have power a low heat hair drier carefully applied will clear it.

Apologies if you've already gone through all that but give us more information and I'm sure that some of the smart guys on here can help you get an image from the sct.

There was no dew as it was covered under a blanket before I started. That was the first thing I checked because as a newbie, that hit me the first night out here in Ohio when is was literally dripping. Maybe I was getting impatient trying to get it aligned on M42 and couldn't see anything except the brightest of stars in the belt. It takes about 2 minutes to switch the scope and DSLR and my first shot it was loud and proud in the LCD screen.

This was part of their bundle mount and scope. We are trying to come to a value for credit on the return of just the SCT.

OK, well I hope you get something sorted out with the dealer. Good luck and I look forward to seeing your images as you progress. It's a great hobby and this is a great place to get help and advice.

Thanks… I am having second thoughts about returning the SCT as I may keep it for lunar imaging and get another for DSO.

Who doesn't need an extra lens or two in their arsenal?

[Mac]

I took so many photos that I hadn't a chance to review them all.

I found this one which was taken at ISO800 and it really shows the nebulosity much more pronounced. There is even some showing around some of the other stars to the upper right.

This is what gets me excited vs. lunar and planetary imaging.

If you look close there is a very faint white line starting in the upper left and comes out the bottom right of the nebula. Not sure if it was a bolide passing thru at the moment I took it.

What DSO object is next down the list in magnitude as compared to M42 that I can try to image?

[Jockinireland]

I took so many photos that I hadn't a chance to review them all.

I found this one which was taken at ISO800 and it really shows the nebulosity much more pronounced. There is even some showing around some of the other stars to the upper right.

This is what gets me excited vs. lunar and planetary imaging.

If you look close there is a very faint white line starting in the upper left and comes out the bottom right of the nebula. Not sure if it was a bolide passing thru at the moment I took it.

What DSO object is next down the list in magnitude as compared to M42 that I can try to image?

Screen Shot 2019-10-12 at 9.12.48 AM.png

That's even nicer.

I think that the nebulosity you are referring to in the upper right is th "Running Man" nebula. You can just make out the dark shadow inside the nebula with head at top, arms and legs pointing forward and back like a guy running. Really cool!

You can do a lot with the sct if you keep it as well as plants and lunar. I use an 8" meade sct and although still a complete beginner I've got some nebula and galaxies which, while far from fantastic are a starting point.

What next? With your telephoto perhaps plaedies, there is some wonderful nebulosity to find there if you get enough time on it and coax it out post processing. A challenge but really worth it. Or some wider fields around cygnus can show much more than you might expect.

If you want to try another nebula on the SCT, how about the dumbbell M27. If you look in the DSO forum you'll see several, one of which is my first effort with my sct.

Clear Skies!

[Hankmeister3]

I see the line, Steve. I don't think it's a meteor. Given the brevity of your exposure and the rather abrupt beginning and ending of the streak, I'd say you captured a satellite. I've had similar streaks of similar length in two and three minute exposures which I initially thought were meteors, but the abrupt beginning and ending to the streak itself pretty much points to a dimly reflecting satellite at extremely high altitude, hence it didn't track all the way through the frame which is often the case. Given the brevity of your exposure the satellite might even be in a relatively low orbit. Of course, depending on when one begins their exposure, one often gets a partial track through their frame. Satellites, of course, are all straight line and generally give a consistent image signature throughout their journey across you CCD/CMOS chip. In rarer cases you might image a tumbling satellite which will vary the brightness of its telltale as it journeys across your astrophoto.

As to brighter DSOs, you might try imaging M8 Lagoon Nebula in Sagittarius to the south/southwest now. With each passing day M8 is nearing a setting point in the West within the next six weeks or so. But if you have a proper southern exposure with little light pollution on your southern and southwestern horizon, you might be able to righteously image it with a 10 to 12 second exposure at ISO1600 with your 135mm telephoto. Also, M20 Triffid Nebula is not that far away and will certainly be included in your frame though it's a bit dimmer and smaller. You will catch a good bit of the Milky Way in that image capture too and don't be afraid to pump up the luminance in post-production in order to enhance your Milky Way capture either. A bit of grainy image is better than no image. Add a bit of contrast to darken your sky background in your astrophoto, too. Just play around with your photoshop controls until it's pleasing to your eyes, grain or no grain.

BTW, there are relatively inexpensive wind up star tracking devices like the Omegon Mount Mini Track LX2 which cost less than $150 that you can buy which should yield acceptable guided exposure lengths of 30 seconds to a minute which are more than enough to capture most of the Milky Way and the brighter DSOs. Then you'll be able to image brighter DSOs like the M16 Eagle Nebula, M27 Dumbbell Nebula, Omega Nebula, Ring Nebula (which is awfully small), get deeper exposures of M42, M13 Hercules Cluster (which will be setting in another month), the Double Cluster of Cassiopeia, and probably another ten or so relatively large scale DSO. The Wild Duck cluster is a nice tight cluster to image because it sits in the middle of the Milky Way and the sheer number of background stars is pretty impressive.

I've even toyed with the idea of buying that Omegon wind-up sidereal rate mini-tracker for use with 18mm to 80mm lenses on the fly. I think a 135mm telephoto will probably be the working limit before the clock-driven inaccuracies catch up to you. But if it really works as advertised, I wouldn't be afraid to take one minute exposures (if you're properly aligned with Polaris and the NCP one degree away) at ISO 800 and 1600 and then live with the results.

BTW, with my Canon 200mm f/2.8 telephoto, it's unbelievable the amount of nebula, DSO objects like star clusters and most of the Messier objects that a 30 to 45 second exposure at ISO 3200 can capture. As with most things, there are trade-offs like between more image capture with higher ISOs like 1600 and 3200 and "grain"/noise. But sometimes you can smooth out that "grain" or subdue the noise in post-production but at least you have an image to work with. So don't be afraid of bumping up from ISO 400/800 up to ISO 1600/3200 at the very beginning until you can get an accurate tracking mount. Actually, even today, I find ISO 1600 to be my camera's sweet spot when it comes to dimmer objects approaching magnitude 9 or 10.

[Mac]

Thanks Hank and Jock for the DSO suggestion to try and image next. I think I will just hang on to the 6"SCT for now as there won't be a lot of opportunity for gazing with winter approaching. It's a bit too cold for my bones to stand out in 40 degree weather let alone the many nights here close to zero.

I have the AVX mount that I used for the 30 sec shot above at 400mm. I need a cable release to use bulb mode as my phone app wasn't connecting to the camera. I think the wifi device I was using mounted to the AVX was interfering as I normally connect no problem.

In regards to getting good PA, it was very easy to see Polaris vs. here at home. But when I used the goto function after everything was setup it was really far off. I have not done a two star alignment yet and it's my next thing to do. Others are getting a couple minutes off their AVX unguided so I am hoping to achieve that.

Hank, don't you think the AVX will serve me well for ' an accurate tracking mount ' once I get it aligned properly?

[Mac]

I was just looking at some wide angle images that included the Andromeda galaxy and the double-star cluster.

This was taken with my Tokina at 14mm f2.8 for 30 seconds.

I think I will try the M8 Lagoon Nebula next as I have a fairly good view to the south but the LP may be too high.

The Andromeda Galaxy could be seen in several shots as a small faint smudge.

Thanks again for your suggestion on DSOs to image next.

[Hankmeister3]

If you can find a way to cobble together a set-up that gives you at least 30 seconds to 1.5 minutes of relatively accurate sidereal rate, if you can get within five minutes of the NCP in both alt and azi (Polaris is less than 45 arc minutes or .75 degrees away from true NCF or "geodetic north") in polar alignment accuracy, there's a whole bunch of DSOs you can image though they will be pretty small in scale. Check out some of my 200mm telephoto shots I've posted in this Astrophotography forum. Now I admit I'm piggybacking on another 'scope and I'm generally polar-aligned enough with my EQ6-R Pro mount which is also capable of 3 to 3.5 minute hands-off PEC + Sidereal internal tracking. Also, you'll need a phone App like "Polar Finder" which will show you where on that .75 degree circle you have to put Polaris from your location and time of day to be within 3 to 5 arc minutes of the NCP. After awhile all this gets a lot easier as it becomes more routine.

I'll post an image that I took 9/23/19 of Omega Nebula and Eagle Nebula to let you see what can be done in 120 to 140 seconds at ISO 1600. Unfortunately I wasn't as super aligned (which is hard to do when working off a throw-down portable tripod and mount) as I wanted to be that evening, but this image is a good proof-of-concept image. This was imaged through my 1990s Canon EF-L 200mm f/2.8 fixed telephoto lens (excellent Japanese glass) mounted on my Canon EOS 77D. I resized the picture in order to post it here so it's not in full detail, though pretty close. And I think I can do better on a more transparent and better seeing night. If you're imaging at f/4 you'll have to double exposure times. BTW, focus and good guidance is just about everything with these kind of astrophotos. I might try capturing some one minute exposures next week when the Moon isn't interfering with DSO imaging and post a sample here.

However, you'll note as with your M42 image, central core "burn-out" is going to be a real issue, especially using higher ISO settings which decrease the dynamic range of your photo. But with single-frame imaging it boils down to either getting an image with extended nebulosity or other celestial features or not getting an image at all. So now I'm planning on posting a 200mm image of M31 in the next couple of weeks, so keep your eyes peeled.

[Mac]

I would be thrilled to get something close to that image Hank. The mount was giving me good tracking at 30 sec and 400mm. It can only get better with the PoleMaster I plan on adding soon. I won't be imaging at f4 anytime soon but I've been looking for some older prime lens like your 200mm f/2.8 for just that reason. The best I can do is f/6 at less than 400mm

[Hankmeister3]

Steve, I think a more realistic representation of the nebula that my Canon 200mm f/2.8 captured in my photo above is the one I'm posting here. I "re-processed" the image by pulling out some color saturation, pumped the cyan channel to reduce the amount of red (some of which is probably noise from a hot camera that night) and then reduced the contrast to yield a better dynamic range which doesn't cause the red channel to really pop. In my original processed image above I didn't add any red or try enhance what appeared to red background nebula, but in adding more luminance to that particular photo during my post-production I more than likely biased the overall image to a significant degree.

But this second picture is probably a more reasonable reproduction of what my Canon EOS DSLR was "seeing" that night: noise, light pollution, skyglow. At f/2.8 at ISO 1600 and exposures around 100 to 140 seconds, astro-images will often get a little crazy. I don't want to mislead you, however really fast lenses with higher ISO values really do register a lot of photons … and noise I guess, so the problem is trying to sort the two out in post-production when dealing with single-frame astrophotography. But yeah, it's pretty cool sometimes the amount of stuff one does pick up in guided exposures of over 2.5 to 3.5 minutes at low f/numbers and high ISOs. You'll learn all about that just as I did when I jumped into the digital astrophotography realm back in April 2018.

[Mac]

Thank you Hank ( or do you prefer Henry )

I have several years of dodging and burning in LR along with other manipulations to enhance my photos. Not a lot of experience in Photoshop yet. The image I took of the Orion Nebula had the whites really blown out but with LR I was able to reduce it considerably and bring out some of the background detail.

Even the 2nd unprocessed image is an image I would be proud to capture and hope my AVX will provide me with at least a minute of excellent tracking. If it's working now at 400mm and 30 seconds without a lot of fuss in alignment, I am sure I can do much better once I get the PoleMaster.

I am a Macintosh software developer since it arrived in '84 and have no love of Windows OS but it's clear that I need a real PC or add another 16GB to my Mac. After installing Windows in a VM, there wasn't much of my 8GB of RAM left to work with when stacking photos.

Thanks for info, I really appreciate it!!

[Hankmeister3]

Steve, you're on the right track. Just keep on the learning curve and you're going to be getting some great single-frame captures of all kinds at DSO 1600. Many consider that DSO to be sort of the "sweet spot" of DSO capture. If you can get even 60 to 90 seconds of really nice tracking out of your mount using ISO 1600 (and even 3200 at times) you will be amazed at what you can capture. This assumes you're working at f/5 to f/6.5. Down the road, If you want to upgrade at some point to a really good and fast imaging telescope, think about getting a six or eight inch f/4 fast Newtonian offered by Orion and Skywatcher (Quattro). However, optical collimation becomes a real issue. But there are some nice six and eight inch f/5 and f/6 Newtonians which aren't as difficult to keep properly collimated if you have a quality laser collimator and a Cheshire eyepiece. But until then, if you can acquire some quality 200mm to 400mm telephotos that are mostly correct for chromatic aberration (CA), this would be the most economical way to go in the near term.

Also, if you take advantage of good seeing conditions (Pickering scale 5 or above) and transparency, you're going to keep yourself busy under the stars! Once you're reasonably happy with imaging the more "difficult" DSOs and learning from others on TSS, you can decide if you want to start stakking, remote imaging to catch hours of "data", and using more "exotic" post-production techniques which really do create some very astonishing astrophotos. One step at a time, learn the craft, accept the failures (I've had many) and stay on the learning curve, my friend. You're doing fine!

BTW, if you can accurately track for 45 to 60 seconds, try your hand now with M27 Dumbbell Nebula. This nebula is sufficiently bright, moderately-sized and is nicely positioned in the sky right now near the meridian. Actually I have both an ISO3200 astrophoto folder and an ISO6400 astrophoto folder which I've created on my desktop just for the fun of it to see how fast I can image certain objects. You will be utterly amazed at what you can capture in 30 seconds but you'll have to live with the truncated dynamic range and the extra "grain". It's almost addictive for us single-frame astrophotographers … well, at least for me it is. Two and three minute exposures opens up galactic imaging (within reason) and a whole 'nother level of DSOs like the Helix Nebula and the M1 Crab Nebula which I'm still working on myself in single-frame capture. Heh!

[Mac]

I think that a fast 6" f/4 is in the cards for next year. I am not sure how the AVX will handle a 8" but it may be OK.

Unfortunately the skies here at home are poor and I am not even sure what it is on the Pickering scale. The next time I visit mom in SC I will be bettered suited to take advantage of it and hopefully there won't be a near full Moon in the sky for most of the night.

After capturing M42, it's got me even more hooked on DSOs.