Moon globe from Sky & Telescope review

If you are in the market for a moon globe, there are only a few real choices. One of the most popular of those choices for years has been the Sky & Telescope moon globe.

Sky & Telescope moon globe

Even as a child, long before becoming an astrophotographer, I was fascinated by the moon. As a kid however things like a globe of the moon was just out of the question. Now that I spend a good portion of my time on astronomy related endeavours, I found room on my desk for another little toy, my own moon globe.

I wanted something that was of course fairly accurate, and something that was large enough to actually be used as a globe. Sure, like most astronomers and astrophotographers I have maps, charts, and programs that will show me every inch of the lunar surface. That is just not the same as seeing where things are in relation to one another, and in relation to the entire sphere. 

Once I narrowed it down to the globes that were reasonably current and around 12″ in diameter, that left me with three choices; the Sky & Telescope model, the Replogle model (probably made the S&T one too) and the Watanabe 3063.

The S&T model moon globe was the best looking sporting a dark gray color, it also had excellent reviews. It is hard to argue with Sky & Telescope, they are very high up the food chain in astronomy circles. The other two, not so much. The S&T one went for $99, not too much.

Replogle moon globe

The Replogle moon globes I found were a little cheaper, but seemed based on an older lunar map, and also had more complaints about fit and finish. I thought this odd because it sure looked to me that they were made by the same people that made the S&T globe, right down to the base. This globe came in at around $80.

Watanabe globe

Lastly, there was the Watanabe 3063 which is a color moon globe where the colors denote the heights of the surface features. The Watanabe is the only topographic moon globe in this roundup. This moon globe supposedly uses data from the Japanese Kaguya spacecraft to make the mappings extremely accurate.

Closeup of the Watanabe globe

Indeed if you look close at this lunar globe, it appears to be extremely detailed, and it should be for the $175 asking price.

I decided to go with the S&T model for now as the more realistic appearance of this moon globe was more important at the time than the hyper detailing on the Watanabe model.

The globe arrived in excellent condition directly from S&T. The assembly consisted of taking the globe out, taking the base out, and setting the globe on the base. 

Sky & Telescope globe closeup

Detail on the globe is very good, everything I was expecting. To see all the detail I needed a magnifying glass, and even with that, the detail holds well. With enough magnification you can of course see the pattering in the printing, but that is at such a magnification that it does not detract from exploring the surface at all.

Seam running across the globe

This moon globe and the Replogle one both have an obvious seam running around the equator of the moon. Once you get one at look close, you can easily see this is where two images have been taped together. No attempt has been made to hide this fact, and it stands out pretty obviously even from a distance. This would be my main complaint with this moon globe.

In comparison, no picture of the Watanabe globe I have seen seems to have any seam at all. This may be the feature that drives me over the edge and forces me to lay down the money for the more detailed, color coded, Japanese globe.

Overall however, I am happy with my purchase, it was the best moon globe for me. It may not be as detailed as one, and more expensive than the other, but I think it strikes a nice balance and looks dang good sitting on my desk. The Replogle is too light colored, and the Watanabe is too multicolored, to pull off what I was looking for. You however, may have something entirely different in mind with your moon globe so those may be a better fit.

If you like the S&T moon globe, you might also look at their other globes, such as the their ones of Venus, Mars and Pluto.

I hope you enjoyed my review of my new Sky & Telescope Moon Globe!


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Monochrome vs OSC CCD cameras, which is right for you?

So you have decided to move up from a DSLR or other regular photography camera to a CCD but not face the question of which variety to get. You have heard about CCDs that are just like a DSLR in that they shoot a color image, while you have heard others shoot in monochrome and require color filters to get a color image. What to do?

Start by understanding that every camera records in monochrome, yes, even your DSLR and one shot color CCDs, and yes, even a film camera!

Above you see a representation of a Bayer matrix used in many one shot color CCDs. The gray squares are the actual sensors in the camera called photosites, each colored square (marked with a R for red, G for green and B for blue) is a filter on top of the photosite (note that all photosites are covered by colored filters, they are removed in this image for demonstration purposes). These are combined to form a single color in the camera so the output you see is in full color. Every four-pixel square (one red, one blue and two green because the human eye is most sensitive to green in normal daylight) is combined using a complex math formula to create one colored area with four pixels of detail.

You can manually do the exact same thing with a monochrome camera and three colored filters:

The four images above are the three color channels and then the final combined image. This is how monochrome imagers create color images, and of course, how your camera works. This is called RGB (easy!).

You do not necessarily have to shoot red, blue and green filters to use this function. This is also how people shoot “narrowband” using Ha, SII and OIII filters, among others. They use a monochrome camera (or in my hard headed case, a DSLR) and shoot one set using the Ha, one set using the SII and another set using the OIII filter and then combine them on the green, red and blue channels respectively (for “Hubble pallet” images). You can mix and match colors, shoot one through a regular colored filter, another through a narrowband filter, and a third through no filter at all, then combine them. You can even combine MORE than three colors by adding new channels! While there are no rules, I suggest you start with standard RGB and/or Hubble pallet narrowband to get a feel for things and then move on.

One reason all this is important is resolution. If you take a look back at the first figure this post you will notice that each photosite, or pixel, records one color. To make a real color image we just learned that you need three colors, red, blue and green. So how does that relate to resolution in the camera?

A color camera, CCD/DSLR/Point & Shoot all work the exact same way. The camera takes a square, one red pixel, one blue pixel and two green pixels and creates one color pixel from these. Basically this takes your 10MP camera and turns it into a 2.5MP camera (10 divided by 4) when it comes to colors, yet it retains the 10MP luminosity. Stripping away the techno-babble this means that your image has the black and white resolution of 10MP (luminosity) but the color resolution of 2.5MP. Said another way, it takes a 2.5MP color image and overlays that color (not the detail, just the colors) on top of a 10MP image.

I know this is a hard concept to visualize so let’s do one more analogy. Take two images, one 2.5MP in size and one 10MP in size. Convert the 10MP to grayscale (sometimes called black and white, but actually has all the gray shades as well) and print them out the same size, the 2.5MP on tracing paper in full color, the 10MP on regular paper in monochrome. Now overlay the 10MP with the 2.5MP and see the results. Note that the edges on the 2.5MP image will be very jagged compared to the 10MP so the color will not line up just right with all the edges. This will cause some blurring on the edges and your objects will not be nearly as sharp and well defined.

Enough with analogies, let’s see what that looks like:

The image on the left is a 300 pixel wide crop of image NGC2244 in monochrome, the image on the right is a 75 pixel color crop stretched over the 300 pixel monochrome image with an opacity of 50%.

This fairly accurately simulates the difference between two cameras, one monochrome and one color, with the same megapixel sensor. Notice how much sharper and clearer the monochrome image is.

So what the heck does this mean? Simply stated this means that a monochrome camera will always have better detail than a color camera if they are both rated at the same number of pixels or resolution.

If it sounds like all the advantages are with the monochrome, you would not be far from the truth. You will always be able to get better images with a monochrome CCD, period. The advantage of a one shot color camera, and it is a big one, is time.

With a monochrome CCD if you want to capture a color image and you need about one hour of capture time, that means you need at least three and preferably four (red, blue, green, and luminance). This means four hours of capturing. If you want to do the same thing with a one shot color, one hour is all you need assuming it has the same sensitivity. For four hours that may not be that big of a deal, but some images I have are made up of twenty or more hours using a one shot color!

Now you can add to your shooting time, processing time. Images from a one shot color are generally faster to process because they are already combined into a color image. Monochrome images require you to combine and calibrate the images to create a color image you can then work with, the one shot color takes all of this work out of the equation. 

So it basically comes down to this; if you are short on time or want an easier time of it, get a one shot color CCD, if you have plenty of time and don’t mind working harder to get a superior image, go for the monochrome CCD.

 


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Orion XT8 SkyQuest 8″ Dobsonian Telescope Review

I have had an Orion XT8 SkyQuest 8″ Dob for a few years now and it has held up well. This telescope has offered up a nice view of a lot of objects but for some reason I have never written about it. Let’s change that. Here is a short Orion Skyquest XT8 review.

Orion XT8 Classic Dobsonian Telescope

Orion 8945 SkyQuest XT8 Classic Dobsonian Telescope

I bought this telescope several years ago and paid less than the Orion Skyquest XT8 price on Amazon, but like most things, prices have gone up a little and they have changed the scope a little. My old Orion XT8 came with a couple of eyepieces and I believe one of Orion’s Deepmap 600 maps which I love. The new one has eliminated one eyepiece and the map, but thrown in a few enhancements we will look  at.

This is the older version which only had a 1.25″ rack and pinion focuser whereas the newer ones seem to come with a 2″ crayford which I can say would be a huge improvement. While this older focuser is not nearly as nice and I can’t use it with 2″ eyepieces, it is still a solid unit.

The newer versions of the Orion XT8 and  my version both come with a red dot finder which is really cheap and flimsy. I much prefer Orion’s Orion EZ Finder Deluxe which sadly is not available any more. You can however get a Astromania Finder Deluxe Telescope Reflex Sight from Amazon which is almost an exact copy, yea!

The best thing about this scope is that it is a solid scope, both in build quality and image quality. My Zhumell Z8 scope is a much nicer scope to use than this Orion XT8 and came with better accessories, but for the money, this is an awesome starter scope and no one will regret buying one. 

Orion’s technical support is also first rate and should you run into any problems, the solution is a quick phone call or email away. You probably won’t need that however because this Orion XT8 is not only well built, but drop dead easy to assemble and use as well.

Opening the Orion XT8 box you find the tube in one section and the base/parts in another. Assembling the base was a simple matter of three side pieces and the bottom, along with a hand full of allen head screws for which they provided the tools. 

Orion XT8 unboxed

Once the base was assembled, you can just set the tube in the base and attach the side springs which put tension on the setup so the scope stays where you put it. Other telescopes I have used have adjustable tension while this one does not, but I fail to think of a scenario that a typical beginner would get into where that would be a problem. In fact, the only time I have used my tensioners on my Zhumell Dob is when I was doing something the telescope was never designed to do in the first place so I am not going to penalize the Orion XT8 for not having it.

About the only thing left is to slide the finder into the slot for it and tighten it down, then grab the eyepiece and start looking around.

Initial thoughts on moving the scope around are that it is pretty smooth in both altitude and azimuth movements. Years later, it is still remarkably smooth. As smooth as the more expensive scopes that use high end ball bearings for everything? Well no, but for much less expensive scope it is more than smooth enough and seems to keep that smoothness over the years. Using the teflon (I am assuming) pads on the altitude might actually be a really good thing as bearings can wear out and possibly corrode, the pads probably will not.

One of the down sides to any Dobsonian telescope, including this Orion XT8, is the cool down time. This is the time it takes for the telescope mirrors to adjust to the temperature outside. Typically you take the telescope from an air conditioned inside to an outside viewing location and the temperature can vary between the two locations by up to forty degrees. This temperature variance causes terrible viewing as the mirrors cool down (or warm up). Once the mirrors have equalized, the viewing is exceptional. Although not included with the scope, Orion does have a cooling fan that attaches to the back of the Orion XT8 to help it cool down faster.

Although I much prefer dual speed crayford focusers in my telescopes, the single speed rack and pinion in my Orion XT8 is pretty nice, and very functional. The newer single speed crayford in the new version of the Orion XT8 I am sure is an excellent focuser. Users I have talked to say it is very fast and smooth and a real improvement over the rack and pinion design.

25mm Plossl eyepiece that comes with the Orion XT8

The 25mm eyepiece provided with the scope is a solid eyepiece for a beginner and provides excellent views of the moon, Andromeda galaxy, Orion nebula, and a host of other popular beginner targets. Unfortunately this one eyepiece choice can leave someone a little lacking so I would suggest you get an Orion moon filter and an Orion 12.5mm Sirius Plossl eyepiece to round things out.

Orion gives you a coupon for a download of some astronomy software included with the Orion XT8. I am not a fan. You can get Stellarium for free off the internet but really, who has a computer out next to their telescope unless they are doing astrophotography? Better options include Orion’s own Deepmap 600 which is awesome in the field, a nice Planisphere (be sure to select the right one for your location!) or any number of excellent phone/tablet apps.

If you wanted something a little nicer you could always go with Orion’s XT8 Plus. When looking at the orion xt8 vs xt8 plus, the plus includes adjustable tension, secondary mirror thumbscrews adjusters, two eyepieces, a 2x barlow and a dual speed crayford focuser for just $100 more:

Orion XT8 PLUS Dobsonian Reflector Telescope

Orion SkyQuest XT8 PLUS Dobsonian Reflector Telescope

Whichever Orion XT8 you decide on, you will have a telescope that should last for many years and provide excellent views.

I hope you enjoyed my little review of the Orion XT8 Dobsonian telescope!

 


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Astrophotography image storage and backup

Astrophotography image captures can add up quickly. They also tend to not be very small. Once you add in darks, bias and flats, you can have quite a mess on your hands. 

Organization

The fist problem is figuring out how to store the files so that it makes sense and you can get the files you need in a hurry. I started off with just a folder where I threw everything in and thought my naming convention would keep my astrophotography image collection organized enough. I was very very wrong.

What I recommend now is a different method, and I suggest you take a look at this one and then make changes to get a system that works for you. Organization is not just so you can go back and find stuff, which you will want to do, but  also to make processing and backups easier.

If you tend to shoot multiple targets in one night and rarely if ever shoot the same target over multiple nights and combine them, the method I recommend for your astrophotography image folders is something like this:

One way to store your astrophotography image collection

This was the first astrophotography image organization system I used. In this case, you start off with a folder called Astrophotography, then make a folder inside of that for each year, then one in that for each session, then one inside that for each target. Lastly, you have folders inside each target folder for each of the image types you are storing. If you are shooting monochrome CCD, then inside the Lights folder you could have folders for Red, Green, Blue and Luminance. Or you might have folders for Ha, S and O3 if you are shooting narrowband.

If on the other hand you tend to shoot the same target over multiple nights you might try something like this:

Another method of astrophotography image organization

In this system, each target can be shot over multiple nights, even spanning years. Either way, you may need to adjust things based on the way you need your astrophotography image collection to work for you. You will probably adjust things over time to better suit you as you evolve.

You might also need folders for processing or storage depending on what your astrophotography software or astrophotography tools require. For example, Photoshop tends to need little more than a PSD file while other astrophotography post processing software such as PixInsight makes a ton of files as it steps through processing towards your final astrophotography image.

How much storage?

This can be a pretty complicated figure which depends heavily on what camera you shoot, and how many frames. Let’s take a look at one session of mine and then extrapolate from there.

On January 3rd, 2014, I imaged Caldwell 4 (among other targets). I took 25 lights, 25 darks, 2 bias and 2 flats along with 5 focusing shots of this target that evening. Each image from my Nikon D7000 is about 10MB in size. In total, there were 59 camera images coming to a total of 590MB of data I want to keep for that one target. That much imaging took about five hours, so let’s say that is about 120MB/hr.

If you are a prolific astrophotographer you might image two nights a month (new moon only) and that works out to about 16 hours a month for 12 months or 192 hours. Multiply that by the 120MB/hr figure we got earlier and you have 23GB of data. Now we need to figure for processing and my experience has been that either with PixInsight or Photoshop I tend to have a lot of image files for processing and output so let’s double our previous figure and say that is 46GB of astrophotography image data.

Of course if you are dealing with FITS files from a CCD the capture images may be smaller, but you will probably have more processing files.

And lest we forget video, if you plan on doing planetary or some high resolution lunar work, our video files might be pretty large as well. Let’s say our video runs about 125MB per minute of capture and a reasonable capture might be five minutes per capture, of which we have 20. That all comes out to about 12.5GB, doubled for processing makes 25GB added to our 46GB to make 71GB of data per year.

Keep in mind that this formula was meant to show you how you can calculate your own data consumption, not really to say you need 71GB of storage per year to put your astrophotography image collection on. Heck, if you get good and you have an astrophotography photos for sale you might want to keep multiple copies in different sizes.

Internal or External?

Now we need to decide on whether we want to keep our astrophotography image collection inside our computer, or externally such as on an external USB hard drive.

Having all our images on our internal hard drive will make finding and processing those image faster, it will also make it easier to fill up our hard drive (a very bad thing) and if something happens to our computer, we could potentially lose our images easier this way. If I was going to buy an internal hard drive for astrophotography image storage I would use this one:

Seagate Green 4TB SATA Internal Hard Drive

Seagate Green 4TB SATA Internal Hard Drive

Putting the images on an external hard drive is moderately safer, and a little slower, although it also gives us portability so we can work on our images anywhere. If you want an external hard drive and will be processing the images while they are on this external hard drive, I would suggest this one:

Fantom Drives Gforce3 Pro 4TB 7200 RPM USB 3.0

Fantom Drives Gforce3 Pro 4TB 7200 RPM USB 3.0

If you just want one to store the images on, copy them to the computer for processing and then copy the finished product back to the external, then I would suggest this one:

Seagate Expansion 2TB Portable External Hard Drive USB 3.0

Seagate Expansion 2TB Portable External Hard Drive USB 3.0

Personally I keep the images I may work on in the near future on my local computer drive and then keep a more “permanent” copy of all my images on a NAS (a big fancy external hard drive that connects through the network).

Backup solutions

You know what is worse than your imaging session getting rained out? Getting awesome images and then losing them because a hard drive failed or you accidentally deleted the wrong folder. That is why you need a backup.

The only real  backup solution I can recommend for astrophotography image backup is BackBlaze. Why them? Because for $95 a year, you can upload unlimited images (or any other data you want) and they will keep it all nice and safe. I should reword that because it sounds like you have to remember to upload your  images and that is incorrect, all you have to do is install BackBlaze and tell it where your astrophotography image files are, then let it do its thing.

In addition, they keep multiple versions of your files which helps protect you from things like cryptoviruses and overwriting files you didn’t mean to. With versioning, you can get the previous version of the file instead of the current one, or the previous to the previous, etc. Click on one of the links for BackBlaze and get a month free trial, what are you waiting for?

Of course they back up not only your  astrophotography image files, but all your other files too!

I hope you enjoyed my article on Astrophotography image storage and backup!


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Our first contest!

FREE ASTROPHOTOGRAPHY BOOK !!

Since this is our first contest, hopefully of many to come, we decided to keep things simple. Sign up for our mailing list and get entered for a free Kindle version of any of the books by Allan Hall currently available. It’s that easy!

AS First Contest!

0m 0s

 

 

This contest is no longer accepting entries.


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Social Media addition to Allans Stuff

Allans Stuff joins popular social media

It is probably overdue but Allans Stuff is finally joining social media. To start off, we will work on getting our blog posts  linked/posted to Facebook, Twitter, Instagram and Google+, in that order. This may take a while to get fully implemented so if you are primarily a Google+ user it may  be a little while before you start seeing content. Of course we will be engaging with our fans on these platforms as well but that too may be a little slow to start with so please bear with us.

We already have a presence on YouTube at https://www.youtube.com/c/AllanHall with about 550 subscribers and over 100,000 video views, so be sure and drop by and subscribe to the channel. There are a lot of good videos already with more on the way.

Follow Allans Stuff on Facebook as AllansAstroStuff , on Twitter @AllansStuff, on Instagram and on Google+.

Of course you can also send a message using the Contact Me form here on the website, or use our newly revamped astrophotography forums.


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Astrophotography objects for beginners book released

Book on astrophotography objects

Today I am proud to release a new book aimed squarely at beginning astrophotographers who want to know what astrophotography objects they can image with their equipment.

From the webpage:

Are you interested in astrophotography objects in the northern hemisphere?

Do you need good information on astrophotography objects that can help you as a starting point?

Taking images of astrophotography objects that are millions of miles from Earth is about as complicated as it sounds and when you start out you will find it hard to target the right ones.

Size, brightness and type are just a few of the more common considerations, but there are many more that relate to the type of equipment you have to hand and what the best tools for the job will be.

Now, with 50 Best Astrophotography Targets for Beginners, you have a handy information guide that will provide the starting place you seek, with information on:

  • How to get started
  • Tackling close astrophotography objects like the sun and moon
  • What the targets look like
  • The best time of the year to shoot them
  • How big the targets are
  • How to find them
  • What the images look like straight out of the camera
  • And much more…

Once you have mastered the techniques needed to take stunning photographs of these amazing beginner astrophotography targets you can move on to further reading on the subject, but making sure that you are taking quality images of some of these is the first step.

Designed with the novice in mind, 50 Best Astrophotography Targets for Beginners provides good, clear information in an easily understood format, allowing you to take the photographs you’ve always wanted to take. It even includes photographs that realistically shows you, as a beginner, what you can expect to achieve. There are no NASA or Hubble images in this book!

Aimed specifically at the beginning astrophotographer using a camera such as a DSLR in the Northern Hemisphere, this is the book you have been looking for.

Get a copy today and see how it will improve the way you take amazing shots of the heavens that will impress and delight friends and family alike!

The book is available today in both print and Kindle editions. 

Buy the book on astrophotography objects now          Get more information on the astrophotography objects book

Get out an image those astrophotography objects!


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