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Sketching is drawing and there are lots of ways to do it, it depends what you are good at ;)

TSED70Q, iOptron Smart EQ pro, ASI-120MM, Finepix S5 pro.

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Just to add, all you need is a sketch pad of reasonable quality paper, a range of different hardness pencils and a decent eraser. I use from 8H through to 4B if I remember correctly (which I often don't ;-) )

Stu

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Sketching is another term for drawing, it is usually done with a pencil, or set of pencils, the different ones being to get lighter and darker shades. Also it is also often monochrome - black and white, so not coloured pencils. Not sure why this is.

A sketch can be simple and quick or go into detail.

Sketching sunspots is a good example as shown in BMS's post above.

I cannot sketch, draw or anything similar. The term drunken spider is close to my ability.

If you look through old observations you will find that people like Messier, Herschel etc will have "sketched" what they saw as evidence for their observations. Some are good, others questionable. Had a good example recently of the Crab Nebula. The original sketch looked crab like so was called The Crab Nebula. When they pointed a better scope at it then it didn't look at all crab like, but the name stuck. It is in effect named after a bad sketch. :eek: :eek: :eek:

I suppose that you are more familiar with the term drawing, and not what I guess is a bit of a specific area of that. To ask a person "Do you draw what you see?" is exactly the same as asking "Do you sketch what you see?".

The "odd" bit about this question is you are the second person to ask exactly the same thing, almost word for word the same question. The other person was based in the US about 5 or 6 months back, where owing to the language similarity I would have presumed that the term was known. Seems otherwise.

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Just draw what you see, then have another go and so on. Eventually your drawings will improve. Like riding a bike, you learn the more you do it, practice practice practice.

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When sketching DSOs there is only one "rule", which is to include an arrow showing a cardinal direction (usually west, i.e. the direction in which objects are moving across the field of view if the telescope is undriven). The rest is up to you. A usual convention is to draw stars as blobs whose size corresponds to brightness: the brighter the star, the bigger the blob.

Advantages of sketching: it makes you look longer and search harder for details. It gives you a permanent record of your impression.

Disadvantages: it takes your eye away from the eyepiece and exposes you to light during the period of observation (fine for planets but not DSOs). The sketch may not be accurate.

I used to sketch a lot, nowadays I rarely do. I find it most useful when looking at dense galaxy clusters, where you can sketch in all the objects you see, then identify them later from charts or images.

In general I prefer to record detail verbally rather than visually. For DSOs, William Herschel's scheme (as used in the NGC) works well enough. I look at the object, summarise its description in my head, then write it down once I've finished looking at it.

The DSO sketches of William Herschel, and the observers who used the 72-inch Leviathan (Lord Rosse etc) were in most cases rudimentary: a hatched ellipse for a galaxy, with field stars indicated, and an arrow showing west. More detailed sketches were sometimes made in the case of unusual or particularly detailed objects, and would be drawn up fully afterwards in daylight. If they were to be published then they would be redone by a professional engraver. The case of the Crab Nebula is mentioned in an earlier post in this thread: in that instance the various stages led to considerable inaccuracy. Lord Rosse's drawing of spiral structure in M51 was a lot more successful.

A picture tells a thousand words, but not necessarily true ones.

Edited by acey
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As others have said, practice. I used to suck but I am okay now. Start with the moon. You don't have to worry about light, so can have one on illuminating the pad. I find my sketches of moon craters are better because I can see. Sketch in a faint line the rough shape, then practice with different shadings to build up to an image. Simple lines and shadings showing a few objects can give a nice rendition of a crater which is fairly accurate. It doesn't necessarily have to be artistic with every pat of the page covered in various shades of grey.

Deep sky objects are harder as it is hard to keep looking at an object, moving away, drawing, comparing if it is accurate, whilst a light shines and your eye keeps adjusting. To be honest, I don't really sketch DSOs. Like others have said, write notes. It really helps as you think about what you are seeing and can compare results over the nights, without having to worry about an inaccurate drawing.


 

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my sketches are basically smudges and dots. I sketch the sun (white light) and planets as well as star clusters and galaxies etc. I am no artist and struggle with complex objects. I see sketches as making my notes interesting and also to allow me to go back later to look at images and see if what I thought I could see (and sketched) is corroborated by the evidence online. this allows me to confidently confirm what I saw and that I have 'ticked off' an object.

sometimes I get it wrong which is also a learning experience.

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I just use sketching as a form of recording my session. I basically imagine a clock face and locate stars as accurately as possible. I make a rough attempt to represent the brightness/apparent size but I'm not to obsessive about it. I've tried a couple of clusters so far, just did them as a smudge with areas of brightness represented rather than accurately recorded to the nth degree.

Mainly I use it as a way to capture my observation and also to force my eyes to tease out every last bit of detail I can.

Just use a cheap sketch book, couple of cheap pencils from the B end of the spectrum, finger, eraser, occasionally a home made blending stump (although usually just the finger).

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Can't really add anything to the advice above but adding voice to the thread :p

You'll appreciate that there are two essential features to visual astronomy: finding the object and observing it. The former process invoves star-hopping and reading star maps, the latter requires you to slow down and actively engage yourself with what is being observed.

Anything just glanced at will always look like a featureless something, so the trick is to go beyond this style of looking and practice picking out features and textures. The best way of doing this is to begin by asking yourself some basic questions, something like:

  • What am I looking at?
  • What have I read about this object that can inform my observation?
  • What shape does it seem to have?
  • How many stars can I see in my field of view? What colour are they? Are there differing intensities of brightness between them? Are there any doubles?
  • Is there anything distinct about the object that strikes my eye?
  • and so on.

These kind of questions would suffice for a well-informed log book entry and if you are going to sketch you are now armed with a better understanding and visual appreciation of the given celestial object.

When you feel you are ready, pick up the given drawing instruments you prefer to use (pencils, chalk and brushes, pens etc) and begin to sketch what you are looking at. It might help to draw yourself a decent sized circle and start by drawing the field stars paying particular attention to their spacing relative to each other and their relative brightness and colour. It isn't always necessary to draw all of the stars you see but the ones you do ought to serve as a guide to the object itself.

Sketching is an iterative, mechanical process: you look through the eyepiece, you sketch a little something, you compare, you look again, sketch a little more, compare, and on and on you go. If you find you are getting bored, relax, take a little break, and when you are ready, return again.

The point of sketching for me is not to create a beautiful rendering of the object itself, but rather to train your eye to see better. If you can do both - I certainly can't - you are extremely fortunate and gifted. But if you feel your sketches don't match up, it doesn't matter, for what is more important is that you have been training your eye and brain to see better in this subtle game of whispering entities and faint whisps. It also means everyone can sketch.

You keep going back and forth from eyepiece to paper until you feel you have either had enough for the night or that your drawing contains most of the details you have seen. Whatever the tools or techniques used, when sketching be sure to use a green or red light and try to be as comfortable as possible.

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Have a look at the images - sketching and unconventional forum on here - I have got loads of advice from this section.  I use black paper/white or greyscale pastel pencils and pens as I can't get my head around colour inversion!

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 I use black paper/white or greyscale pastel pencils and pens as I can't get my head around colour inversion!

Black paper and a white pastelis / pencil are much more challenging to work with.

I always worked with a white paper and simple graphite pensils + q-tips. I did try to make a sketch or two on a black paper - and it was really tough.

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Black paper and a white pastelis / pencil are much more challenging to work with.

I always worked with a white paper and simple graphite pensils + q-tips. I did try to make a sketch or two on a black paper - and it was really tough.

Difference of opinion here!  Either way might work for you - good to know that there are different ways to approach it though   :smiley:

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