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Sketching practice

At the ASEM beginners meeting last night (4 December 2014) we talked about sketching astronomical objects. During the discussion, I talked about developing and honing your skills by making drawings from actual photographs. This method allows for practice and development in a comfortable environment (and around Missouri, we have more cloudy nights than clear ones so I use that time productively).
 
Once you've developed a stable technique, you can then move on to developing the equipment and techniques you'll use in the field (we didn't talk about THAT in detail - maybe next month).
 
After the meeting, several links went out covering resources available to the sketcher. Three of the links are relevant here. The first is the book that I've used as a reference for years. It's "Astronomical Sketching: A Step-by-Step Introduction". (Click on the title to go to the publisher).
 
The second link is to a Youtube video by Jeremy Perez. This video shows you how to sketch by using the galaxies M81 and M82.
 
The third link goes to Michael Bernardos' video who uses M45 as an example.

I found the videos interesting in that the tools and techniques I use and have developed independently are very similar to Jeremys and Michaels - Thanks mom and thanks Michael & Jeremy!

Having mentioned that practice makes perfect and you can do it at home AND needing to freshen my skills a bit, I decided to run a practice sketch using Jeremy's video and an image supplied by Dan Crowson.
 
Dan is our local astrophotographer whose work has appeared in many websites and periodicals. He's REALLY good! He graciously allowed me to post his image for use in this exercise:
 
 
Want to see more of his EXCELLENT images? Go here: https://www.flickr.com/photos/dcrowson/
 
 
So here is a step by step result of that effort:
 
 
So here I have my standard 5"x7" drawing form setup on a small 8"x6" clipboard. The image is displayed on the laptop screen. Since this is just an exercise in drawing skills, I have taken no effort to simulate the view or the setup to match my telescope and observing position. That's "Advanced practice". I should note that the only tools I use at the scope are a mechanical pencil w/2H lead, a 3B pencil for shading, a small piece of pink pearl eraser, a no. 3 blending stump and a red flashlight. Once I have the basic drawing constructed using those items at the eyepiece, I'll move to a desk (or desk like platform) to finalize the sketch. A few trips to the eyepiece will usually be needed.
 
 
 
 
 

 
The first thing to do is locate and place the objects on the paper. I start with stars and just place them without much attention to brightness. I will note the brightest and the dimmest stars in the field. As for the dimmest, I'll want to identify one each from direct and averted vision but this is just for reference purposes.
 
 
 

 
The next steps are to fill in the galaxies and begin the smoothing and detail process. This uses the blending stump exclusively.
Fill and smooth the galaxies. Use the eraser and blending stump to finalize the appearance of the galaxies.
 
 
 
 


 

 
The last major steps are to
  • Ink in the stars at their relative brightness (I use a 005 pen as it gives the blackest value and works for stars from mag 12 to -24).
  • Add the simulated the spider vane spikes and the "fuzziness" surrounding bright stars.
  • Fill in the data blocks
  • Make any relevant notes.  













 
Here I photographed the result, converted the image to black and white and then turned it into a negative. Total time
: Less than one hour (with lunch). 
 
 
 

Original model 
 
 

M81 in the drawing doesn't look very much like the photo does it? Well, that's what practice is all about. The drawing DOES look an awful lot like the results I actually get at the eyepiece, in the field, in the dark and in the cold ;)
 

 
The "Tools of the trade"
 
All I use are 
  • Two, (maybe three) pencils
  • No. 1,2 & 3 blending stumps
  • a black inking pen,
  • A bit of carefully shaped Pink Pearl Eraser. I have not tried the malleable eraser Jeremy and everyone else suggest. I've been cutting up Pink Pearls for years and they do me well.
  • Some kind of sandpaper for cleaning up the stumps and putting ultra fine points on pencils.
  • At the scope I use a variable intensity red light on a clamp or a small red light I hold between my teeth. That's another practice session: Turn the intensity of the laptop screen WAY down and try to draw the image in the dark AS IF I was at the scope.
 

 
Q&A (I'd post this in the comments section but it limits the amount of text).
 
I received a question from a member who attended last night. It is a good one. It and my response belong here:
 
His question:
 
Very helpful. Do you mark all stars seen through the eyepiece? Why bother with those you can only see with averted vision? If you do not mark all the directly visible stars, what criteria do you use to make your selection? Does this vary depending on the object being drawn (nebula vs. open cluster vs. globular cluster vs. galaxy, etc.)?
 
My answer:
  
I didn't mention this last night but one of the first things I do at the eyepiece is just take in the field. What contributes to the drawing and what's just extraneous "flotsam and jetsam".
  
I don't necessarily mark all stars in the FOV.
  • I mark stars that help to establish the relative positioning of the object in the field of view. In the case of moving objects within the solar system, it helps to identify their location relative to known stars at the time of the drawing.  
  • I will mark stars that form an interesting asterism.
  • I will mark stars that enhance the drawing.
  
Star content does vary from object to object and field to field. Think of the Trapezium. If you're drawing M42 you certainly want to include those but you might not have time to include all the stars in the periphery of the field. Some stars can be left out as they may not contribute to the overall balance of the drawing or they "clutter" the view.  Start with the important ones first and work down.
  
Nebula, Open and globular clusters present a different problem with respect to fidelity:
  
On the one hand, there may be so many stars in the FOV around a Planetary nebula that you may get bogged down trying to draw them all and miss the subject of the drawing - the nebula itself. Don't forget to include enough stars to indicate (or imply) field density.
  
On the other hand, fidelity could be necessary for the Open or globular cluster so you MIGHT get bogged down drawing the stars in the cluster.
  
Let your time and sky conditions drive what you include in you're drawing and how much time you spend on it. I think the important thing is to capture what YOU think is the story of the drawing - Know what I mean? What is it you're trying to capture here? I'd let drawing fidelity increase with experience and taste.
  
As for the dimmest stars? That just gives me a reference to how transparent the sky was and how well me and my scope were performing - it's just data, not part of the composition.
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