[cprobertson1]

If you have the money, the best small (DSLR based) tracking mount you can get is the Skywatcher AZ-GT1. AZ-GTi Mount – Sky-Watcher USA

It will support a payload up to 11 lbs, has go-to capabilities so it's easy to find the faint fuzzies to photograph. can work in Alt-AZ or EQ mode (with a firmware upgrade) so you can take longer exposures.

It's light at around 8lbs so you can take it on a hike to a dark site with no light pollution.

It works with smartphones to do alignment/go-tos or you can buy an optional hand controller.

Runs about $400 including the wedge for EQ mode.

Nice - it may be my first real upgrade if I get into the field!

I've been working with only the tripod lately - just getting used to taking photos in the dark to be honest: only had one real opportunity just before xmas to photograph the moon - its' been very overcast of late! I did however down a shot of the stars just before new year... mostly because I couldn't feel my fingers and by the time I warmed up I didn't want to go outside again!

Remember that you can get very good results with old glass. I had a link to Pete_XL's capture of the objects in Orion that he captured with a SMC Pentax-A 200mm f/4 lens from 1982 or something like that. I have the S-M-C M42 mount version of that lens and I paid like $40 for it so getting glass that is good enough isn't that expensive. That and some times you can't basically steal a lens like I did with my Sigma 300mm f/4 APO macro that I got for $130 if you keep your eyes open.


Unless you have a big telescope and are willing to do lots of processing this will likely be a hard one to do. By big I mean big like 2000mm (yes 2,000mm) or more. With my 300mm and K-3 when I shoot jupiter it is only about 17 pixels across. I'm not trying to discourage your, just trying to set expectations.



No I mean I posted some real stinkers but I was looking for help which is why I posted them and I did get that. There is a fair amount of technique required in taking the shots, but there is also even more skill required for editing them. Astro pics have so few photons you are really trying to make the most of them and things can go sideways easily. Ask questions early and often when starting so that bad habits don't develop.


I've never gotten that or given that advice and I don't think anyone would here either. All of the criticism that flows over in the astro group is constructive and advice on how to correct what ever issue is being discussed is always given. Also don't be intimidated by the posts you may see from VoiceOfReason, DrawsACircle, or Pete_XL, they are all masters and are very helpful.

Ha! I've actually fallen in love a little with my sigma lens - took it out birdwatching the other day with a DIY red dot reflex sight on the hot shoe and it was surprisingly good, even with the 2x teleconverter (though the latter caused bad chromatic aberration, not sure if it will be useful for astrophotography) - I'll need to be on the lookout for more old glass - I keep saying I'm going to visit the local antique store (he has a table of old SLRs, a few of which must be pentax - and who knows, I might find a lens or two in there as well!)

Good call on asking questions early! I'll make sure I join the astro group today - and I'll try not to be intimidated by the masters, but I can't promise I won't be

As I mentioned earlier, I've not been out much - over the festive period - between having the flu and a nasty cold and family and Christmas-dinner-induced-food-comas, and worst of all, clouds, I've only managed to take some shots of the moon - going to use them for stacking practice!

That reminds me, can you suggest some free/freeware stacking software? I've seen/heard reccomendations for RegiStax and Deepsky Stacker but haven't really looked into them yet (what little I've done so far was aimed at getting used to photographing the sky in the dark rather than the stacking side, though I have also taken some series of shots intended for stacking, I just haven't gotten round to it yet!

As for setting my expectations [of planets] to reasonable levels - not going to lie, I'm expecting a blurry dot/line at best *


*Side note about capturing a few pixels - I decided to try to appreciate the size of the mozaic image taken by voyager I as it left the solar system the other day and found out lots of cool things, looking back at earth and was amused that it had two cameras: a 1500mm, f/8.5 narrow-angle camera and a 200mm, f/3.5 wide-angle camera - and ultimately capture the image on an 800x800 pixel "sensor" (actually a vidicon tube! It's still a sensor in a utilitarian sense though!). It's quite something when you're so far away from your target that a 3.2-degree field of view is considered "wide angle" xD Really puts things in... perspective.

So! They returned 60 frames of which three (with blue, green and violet filters) were returned and combined to get the final image of Earth, as seen through the 1500mm lens from a tiny 3'757'059'000 miles away on a 41 year old vehicle travelling at 40'000 miles per hour (6'046'400'000km, 64000km/h (nearly 18 km per second) and the return signal took five and half hours to reach earth (despite traveling at the speed of light).

How cool is that!? I even found an appendix showing the specs of the cameras used!

[MossyRocks]

hat reminds me, can you suggest some free/freeware stacking software? I've seen/heard reccomendations for RegiStax and Deepsky Stacker

For starting out Deep Sky Stacker (DSS) will work well for star fields and deep sky objects. For shots of the moon or things like planets (assuming you have a large scope) RegiStax or AutoStakkert! would work. DSS doesn't do planet or moon stacks and I don't believe the other 2 would do star field stacks. There are other programs that people use too. I have staked pictures of the moon using GIMP and Photoshop for the stacking portion and the Hugin component align_image_stack. When I did it in photoshop I used it to do a final alignment. Sometime people use DSS to only create aligned output files and then load those into another program for stacking. When using DSS don't use it's image editing abilities they are awful, just use it for stacking.

[dick897]

Tagging for later

[Craigbob]

Another good free stacking program is Sequator. It's designed for stacking night landscape/Milkyway images and has some good tools for that. But it also does pretty decently on deep sky images.

[cprobertson1]

It's been a heck of a learning curve, but I managed to stack the pictures I took on the 24th of Dec (2018) - 8x images taken on 2018-12-18 with a 300mm lens at f/11, 1/50s, ISO100 and stacked with RegiStax

It may not be great, but I like it I will hopefully get a bit more practice and hopefully some more moon shots in the near future Thank you all so much for the help! I have to say, that image came out far better than I had anticipated - yeah, it could be better (there's a lot of noise, for instance!), but for a first attempt I'm very pleased with it!



I'll no-doubt resurect this post if/when it comes time to start upgrading gear xD

[MossyRocks]

It's been a heck of a learning curve, but I managed to stack the pictures I took on the 24th of Dec (2018) - 8x images taken on 2018-12-18 with a 300mm lens at f/11, 1/50s, ISO100 and stacked with RegiStax

Were you on a tripod of hand held?
Either way I would suggest backing off the f-stop some and shooting at f/8 and 1/100s, maybe up the ISO to 200 as well and shoot at 1/200s. The amount of noise at ISO 100 with a 8 pic stack seems excessive even if it were just a single shot it still seems really bad. Was the focus off and did you sharpen a bunch?

Going forward I would suggest work on nailing the focus, do it manually as the autofocus for me never quite nails it. Also if considering doing a stack put the camera in burst mode and blast away and load 30 to 100 images in a stacker.

It is still better than my first moon shot.

[cprobertson1]

Were you on a tripod of hand held?
Either way I would suggest backing off the f-stop some and shooting at f/8 and 1/100s, maybe up the ISO to 200 as well and shoot at 1/200s. The amount of noise at ISO 100 with a 8 pic stack seems excessive even if it were just a single shot it still seems really bad. Was the focus off and did you sharpen a bunch?

Going forward I would suggest work on nailing the focus, do it manually as the autofocus for me never quite nails it. Also if considering doing a stack put the camera in burst mode and blast away and load 30 to 100 images in a stacker.

It is still better than my first moon shot.

That was with the tripod using a remote release and manual focus; I'm not the logic behind why I was using ISO100 though! Will keep that in mind when I'm taking my next shots - hopefully I'll have a clear sky in the near future!

I think a lot of the noise came from post processing - BUT the images were probably very slightly out of focus to begin with, which I attempted to compensate for with very novice (and no doubt heavy-handed) use of the wavelet controls - and then I emphasised any defects I had introduced from that when I cropped the image.

I'll give the stacking another go with that set of images and see if I can do a better job of the post processing - can never have too much practice! With any luck I'll get another clear night soon and I can give the image capture another go as well!

--EDIT--
Will a Batinov Mask work for/aid in focusing on the moon? I'm debating printing/cutting one out but it's a bit of effort if it won't do anything (that said, I'll still need one eventually!)

---

Last edited by cprobertson1; 01-07-2019 at 02:58 AM.

[MossyRocks]

That was with the tripod using a remote release and manual focus; I'm not the logic behind why I was using ISO100 though! Will keep that in mind when I'm taking my next shots - hopefully I'll have a clear sky in the near future!

I think a lot of the noise came from post processing - BUT the images were probably very slightly out of focus to begin with, which I attempted to compensate for with very novice (and no doubt heavy-handed) use of the wavelet controls - and then I emphasised any defects I had introduced from that when I cropped the image.

I'll give the stacking another go with that set of images and see if I can do a better job of the post processing - can never have too much practice! With any luck I'll get another clear night soon and I can give the image capture another go as well!

--EDIT--
Will a Batinov Mask work for/aid in focusing on the moon? I'm debating printing/cutting one out but it's a bit of effort if it won't do anything (that said, I'll still need one eventually!)

Using ISO 100 is acceptable, I usually will use ISO 200 to get a faster shutter to help with shake. I usually shoot the moon at ISO 200, f/8, and 1/400s. Also if shooting off a tripod disable the image stabilization.

A lot of astro imaging is with the processing which takes a lot of effort to learn. Everyone who starts out faces a pretty steep learning curve and makes a bunch of mistakes they didn't know they were making. I would say steer clear of wavelets when starting out and instead try a workflow more like this:
1. Stack in your favorite stacking program and if possible do a 2x drizzle. The 2x drizzle is an upsizing of the image and the alignment and stacking is done on the larger upscaled image. This will result in a better alignment and also finding more detail.
2. Open the stacked upscaled image in Photoshop or GIMP (doesn't really matter)
3. Do 2 unsharp mask edits. One with a radius of 3 to 4 pixels and 50-100% and the second with a radius of 150 to 250 and 7-15%. The first one will bring out more of the fine details that will be kind of fuzzy in upscaled image and the second will add clarity and pop to the larger structures.
4. Do a curves adjustment to increase the contrast. This gives it more pop and will help with some of the flatness of the image.
5. Once satisfied down scale the image back to the original dimensions and post to facebook and wow your non photographer friends and family.
6. Now go shoot more pictures and do the same things all over again because your second attempt will be better.
There are more techniques for processing astro images but these are fairly mild and easy to understand. I have only started dabbling with wavelets and don't really understand them yet so I can't provide much if any advice on how to avoid things going sideways with them. I should probably dabble with them some more especially with my fogged lens moon shot as it could probably benefit from them and it would be a good learning experience.

As far as focus it does take practice especially if you don't have a focusing aid. When I have shot the moon in the past I have usually had to tinker with the focus a fair amount to really nail it. To your question about a bahtinov mask for focusing on the moon and if it will work. Yes but when focusing you don't point it at the moon as you really need something that is more a point source of light and not a large disc. I use one when getting the focus nailed but instead will point it at a bright star. Sirius is a good candidate, if it is up, as it is really bright, and I can focus using live view with ease. When I use a bahtinov mask I always focus on a bright star and then move to the target now. From your lens's perspective the moon and all the stars are all at infinity. The one I made I decided I wanted to have as many slits as possible and have as much open area as I could. I used the generator here which gave me a SVG file and then loaded that into an opensource CAD program to create the 3d printer file. There was some finishing work with the printed mask to smooth it out and clean it up but that wasn't hard. The mask I have now basically makes my 300mm f/4 lenses 300mm f/8 and it is really easy to nail the focus now. I get huge bright spikes that are easy to align in live view.

[cprobertson1]

Lots of good tips there - can't wait to give it a proper trying out!

I think the logic behind my using ISO100 was that "I can get away with it therefore I should" (the moon being so bright that I could afford the low ISO!) - and I think that's as far as my mental processing went

Ah, good shout on using a point source instead of the moon itself - I'd have tried to use the moon had you not said that (and probably gone "huh, that's not too great" afterwards).

Now I'm about to ask a n00bie question that betrays my regular photography-n00bieness too :P At my parents house (Class 4 on the Bortle scale, vs a 6/7 at my home location) there is a radio mast with a big red anti-collision beacon 5 miles away. The noobieness comes from my wondering: as far as my lens is concerned, is that at infinity focus? Would I be better using/does it have to be an astronomical object?

This question brought is brought to you by a poor understanding of infinity focus with respect to lenses (I know what infinity focus is; I do not know the specifics of how to achieve it!)

--EDIT--

I know what infinity focus is in principle (the point beyond which which light is effectively collimated (or very close to it at least) but I'm not terribly sure where that is with respect to a lens; I would assume it is at some distal point; but where is the cutoff point where the light has very suitably low divergence?

Hrm... wait... I just had a flashback to hyperfocal distances... 5 miles should definitely be beyond the hyperfocal point - does that mean if I focus on it everything beyond that should also be in focus (since I'm not worrying about things in front of that point, the moon being a little bit further away rather than close xD) - my sigma lens has hyperfocal markings on it as well... but that raises the question, when I turn it to the infinity symbol (which I always assumed was infinity-focus) - why will it not focus on perfectly on stars or the moon, which I would have assumed to have been beyond the hyperfocal distance? Is this just poor calibration on the len, wear-and-tear, or something more interesting?

--EDIT-Part-2--
Whoops! Answered my own question! "Modern" lenses focus past infinity to allow compensation for thermal expansion and for IR shooting. Not sure if my Sigma lens is "modern" but it certainly seems to go to infinity and beyond :rofl:

[MossyRocks]

I think the logic behind my using ISO100 was that "I can get away with it therefore I should" (the moon being so bright that I could afford the low ISO!) - and I think that's as far as my mental processing went

That is perfectly fine thinking but putting a bit more ISO into it and getting slightly more noise per shot makes up for being able to get that faster shutter. Having a faster shutter also allows you to have a better chance of catching those fleeting moments of atmospheric clarity and minimizes any movement/shake blur as a 300mm lens really magnifies them.

there is a radio mast with a big red anti-collision beacon 5 miles away. The noobieness comes from my wondering: as far as my lens is concerned, is that at infinity focus? Would I be better using/does it have to be an astronomical object?

Probably unless you are using a huge telescope. For a 300mm lens that should be far enough away. However if you are using a bahtinov mask I'm not sure if that light would be enough of a point source to give good results. I depends on how big the light is and if, when magnified, it is only a handful of pixels across (point source) or if it is in the teens across (disc). You really want a point to get the best spike alignment. I usually stick to a star as they are always visable and just pick a really bright one. It helps if you get the focus close to infinity first as the bahtinov mask basically makes it almost impossible to see things that aren't close to proper focused. You will learn where this close enough point is on your lenses after using them a few times. For example on my 300mm if I set the focus line so it is half on and half off the infinity (just shy of the official infinity mark) I am pretty close and can see the spikes clearly even if they aren't properly aligned yet. You will have to zoom in with live view to seem the spikes. If you don't already know where it is my suggestion is the following procedure:
1. set the lens to it's infinity focus marker but do not have the bahitnov mask on yet
2. turn off focus peaking (when doing astro shots it seems to cause more problems than it is worth)
3. go into live view and get the star about as small as you can
4. put the bahitnov mask on
5. using zoomed live view align the spikes
6. Now look at where real infinity focus is and take a mental note and use this point as a starting point next time and you only have to step 5

With astro photos you are going for really crisp images so the thermal expansion and contraction does produce a noticeable difference in focus and is a concern when going after DSOs but shouldn't be with moon shots as those are just go and quick shoot a pile. I usually let my lenses acclimate to the temp first before doing an initial focus. I usually shoot in a bortle 5 but that is a 40 minute drive from my house (very bright bortle 8 almost a 9) so they mostly cool down in the trunk on the drive. Then I leave them out when I am getting things setup. If you are having falling or rising temps (more than a a couple degrees) it may be worthwhile to adjust the focus every now and then to keep a proper focus. The last couple of times I have been out the temp has been pretty steady so I haven't refocused.

[cprobertson1]

That is perfectly fine thinking but putting a bit more ISO into it and getting slightly more noise per shot makes up for being able to get that faster shutter. Having a faster shutter also allows you to have a better chance of catching those fleeting moments of atmospheric clarity and minimizes any movement/shake blur as a 300mm lens really magnifies them.



Probably unless you are using a huge telescope. For a 300mm lens that should be far enough away. However if you are using a bahtinov mask I'm not sure if that light would be enough of a point source to give good results. I depends on how big the light is and if, when magnified, it is only a handful of pixels across (point source) or if it is in the teens across (disc). You really want a point to get the best spike alignment. I usually stick to a star as they are always visable and just pick a really bright one. It helps if you get the focus close to infinity first as the bahtinov mask basically makes it almost impossible to see things that aren't close to proper focused. You will learn where this close enough point is on your lenses after using them a few times. For example on my 300mm if I set the focus line so it is half on and half off the infinity (just shy of the official infinity mark) I am pretty close and can see the spikes clearly even if they aren't properly aligned yet. You will have to zoom in with live view to seem the spikes. If you don't already know where it is my suggestion is the following procedure:
1. set the lens to it's infinity focus marker but do not have the bahitnov mask on yet
2. turn off focus peaking (when doing astro shots it seems to cause more problems than it is worth)
3. go into live view and get the star about as small as you can
4. put the bahitnov mask on
5. using zoomed live view align the spikes
6. Now look at where real infinity focus is and take a mental note and use this point as a starting point next time and you only have to step 5

With astro photos you are going for really crisp images so the thermal expansion and contraction does produce a noticeable difference in focus and is a concern when going after DSOs but shouldn't be with moon shots as those are just go and quick shoot a pile. I usually let my lenses acclimate to the temp first before doing an initial focus. I usually shoot in a bortle 5 but that is a 40 minute drive from my house (very bright bortle 8 almost a 9) so they mostly cool down in the trunk on the drive. Then I leave them out when I am getting things setup. If you are having falling or rising temps (more than a a couple degrees) it may be worthwhile to adjust the focus every now and then to keep a proper focus. The last couple of times I have been out the temp has been pretty steady so I haven't refocused.

Totally printing that off for tonight's shoot! I'm headed to the harbour front tonight for a SCUBA lecture - BUT I plan on showing up early because it's the harbour front where I'll have panoramic view over the sea and very little light pollution from the west (obviously I'm expecting lots of diffuse skyglow from the North, East and South... but hey! I'll live with it My guess is a bortle-6 - let's see if I was right!) - anyway, I should be able to have a bit of fun before my lecture at 1930

That was a very good shout on the bahtinov mask by the way! I had actually discovered that exact site earlier in the day and had the same day you did!

Will let you know how tonight's shoot turns out - I'll post it over in the astrophotography group so I can keep a record of my adventures :P

[cprobertson1]

Totally printing that off for tonight's shoot! I'm headed to the harbour front tonight for a SCUBA lecture - BUT I plan on showing up early because it's the harbour front where I'll have panoramic view over the sea and very little light pollution from the west (obviously I'm expecting lots of diffuse skyglow from the North, East and South... but hey! I'll live with it My guess is a bortle-6 - let's see if I was right!) - anyway, I should be able to have a bit of fun before my lecture at 1930

That was a very good shout on the bahtinov mask by the way! I had actually discovered that exact site earlier in the day and had the same day you did!

Will let you know how tonight's shoot turns out - I'll post it over in the astrophotography group so I can keep a record of my adventures :P

Eeep... that... didn't go well!

For starters, it was windy as **** which did not help matters; I don't seem to be able to get them to stack right - not sure what's going on there xD

Oh well! I'll just need to try again! :P

[MossyRocks]

I don't seem to be able to get them to stack right

If you have photoshop you can always give that a try for stacking. Different programs do alignment differently and sometimes the image will cause problems for different algorithms. When I have had problems stacking things I usually will try starting with a tighter crop of the object, in this case the moon. Also I have found that a thin crescent moon does seem to produce more issues when stacking. I would suggest trying some other alignment or stacking programs. Some others to try:
1. Photoshop (if you have it)
2. AutoStakkert! (free)
3. align_image_stack program which is part of Hugin (free but you just get aligned output file that you have to manually stack)

Those are the 3 that I have used in addition to RegiStax and I have always been able to get one of them to stack the images of the moon correctly. You may need to put in some manual control points in AutoStakkert! or RegiStax instead of it doing it automatically. Also do a 2x upscaling first before using any of the stackers and make sure the crops are all the same size. If you have only a handful of images (basically 10 or less), to stack use bicubic smoother to avoid the jaggedness, but if you have a bunch (more than 16) use nearest neighbor for the upscaling, in between it is kind of a tough call and I usually try both and see what produces the best result.

The wind may have been what did you in. If you have too much shake it may be making too much of a mess of the image for the stacker to find those nice spots to align on. If out again shooting the moon in such a situation I would probably suggest upping the ISO to 400 or even 800 from 200 and then increasing the shutter speed to 1/800s or 1/1600s.

[cprobertson1]

I'm afraid I lack photoshop - I use darktable for RAW processing and gimp for actual manipulation - though I find myself using gimp less for photos I take these days

You know something - I was reading something related to registax in that it's not really designed for dealing with full resolution images (which would certainly explain the out-of-memory errors I was getting when trying to use drizzle, resampling and any other options when stacking) - apparently autostakkert is a popular choice for the actual stacking, followed by registax for the wavelet processing (which, in the words of one eager commenter, is in fact "the shiz")

So! Cropping: what is the best (by which I mean easiest) way to crop a whole bunch of images?

Take for instances my picture of vega: it has the brightest group of stars in a corner (I placed lyra in the top right of my frame with intent on capturing some of the dimmer stars in the direction of the coathanger cluster - more for the sake of experimenting and seeing what can be drawn out of a given image rather than a deliberate attempt at anything!) - if I crop on the centre of the image, lyra will be cut off - is there a way to automatically crop, say, fifty images on a particular group of objects (or the brightest object?)

[cprobertson1]

When I started my "Adventures in Astrophotography" post over in the Astrophotography group, a number of people reiterated the suggestion on using the O-GPS1 and that it'd be a worthwhile purchase, and I'm certainly being swayed by it!

So obviously it provides rudimentary tracking and GPS functionality - but what I was wondering was, if properly calibrated, does it also record the orientation of the camera (specifically the azimuth/elevation)? I was out taking pictures this morning and forgot my notepad, and I would usually record roughly where the camera was pointed so that I can find it again later in stellarium :P

I don't believe it does; just curious :P