CLOUDY NIGHTS FORUM ARCHIVES
"Live Forums" can be found here: Live Forums


Astrophotography and Sketching >> Sketching

Pages: 1 | 2 | (show all)
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
How do I do it - Sketching a simple open cluster
      #3407984 - 10/24/09 11:12 AM

Open Cluster NGC 1664 in Auriga.

Step 1

Once you've located the object, enjoy the view and try to get an overall impression of the cluster. I also prefer to sketch the object so that north is up and east to the left. This is an easy thing to fix later on but I still try to rotate the field so that north is up if possible.

You can use low power to note any specific colors in stars, star chains and so forth.

In NGC 1664's case here are some features that I noticed @ 37x:

1.) Bright 8th magnitude star SE from the cluster.
2.) Five magnitude 10-11 stars in the cluster.
3.) Y-shape of the cluster, resembling that of IC 4665.
4.) Little asterism ~35' NE from the cluster.

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3407993 - 10/24/09 11:16 AM

Step 2

Find a good magnification. Do not make the object fill the entire field - this (usually) greatly reduces the visual impressiveness of the cluster. Do not sketch the object to a too small field of view - this makes the object (of course) difficult to sketch. A good rule is not to let the object fill more than 1/3 of the field.

For NGC 1664 I selected 96x (31' field of view) on an 8" Orion DSE. This is a fairly good match with the 1/3 rule (cluster's size is roughly 10').

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408001 - 10/24/09 11:19 AM

Step 3

There are two ways to do the next step.

First way is to plot and sketch bright stars in the field to use them as reference points. This way you get the field stars and field pretty well cemented to the correct positions but might have some issues regarding the object itself (scale).

The second way is to start with the actual object (and in this case the cluster). I find this way the best for me, although plotting the field stars after the actual object might cause some problems (scale).

So get as comfortable as possible and start sketching. I personally use a chair, headlamp and a ruler while sketching. A ruler is especially helpful as you can use it to accurately mark star positions in a geometrical way.

Also round up the stars if possible.

After step 3, your sketch might look something like this:

Step 3 sketch - primary stars sketched

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408006 - 10/24/09 11:21 AM

Step 4

Now you should have a pretty basic outline of the cluster. If you're happy with the result you can move on to start sketching the field stars. If not, I suggest you start over or apply some fixes.

I personally do all of my sketches by combining the views with different magnifications. In this case, NGC 1664 can take magnification pretty well but the suburban sky cannot. I often double the magnification or use over 200x for the next step but on this night seeing wasn't too good so I used only 200x.

Anyway, at 200x you can see the fainter stars more clearly and can bring out few additional stars from the background. Sketching these stars will make the cluster appear richer and sometimes more... inviting. One can argue about the realism of combined sketching but if you're against it, you can always sketch the stars you can see with the primary magnification and leave it to that.

Now, since I do use at least two magnifications on an object when sketching, I've added all the faint stars I could spot @ 200x to the sketch and made sure all of the stars are round.

After step 4 the sketch looks like this:

Step 4 sketch - primary stars + secondary stars @ 200x

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408014 - 10/24/09 11:24 AM

Step 5

Next step is the step I find the most difficult. Sketching star clusters that contain geometrical patterns or even some sort of shapes (99% of all clusters do) is pretty easy. I personally try the sketch only the cluster and minimize the amount of extra field stars I have to sketch.

As you can see from the sketch above (step 4 sketch), this is how I visualize the cluster. It hardly is the exact same size that the true physical cluster is and surely is missing some true cluster members... but you can think of this as an artistic impression of NGC 1664.

But the next part is a critical one. You can sketch all the field stars if you want but in my opinion you just end up wasting a lot of time sketching all the stars you can see. How I do it varies depending on the night, my mood and patience.

For argument's sake, I've added more field stars than I usually do. I find it that too many field stars tend to steal away some of the actual cluster's beauty and impressiveness.

This is usually the time when I write down magnification, directions and all other info to the sketching form. After a few days I can hardly remember anything about a specific observing session so it is better to be safe than sorry with the little details.

After the final stage of sketching the sketch looks like this:

Step 5 - The final unscanned version

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408017 - 10/24/09 11:25 AM

Step 6

Time to scan the sketch with a scanner, crop it to 400x400. Here is what the unedited, scanned version looks like:

Step 6 - The final scanned version

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408019 - 10/24/09 11:26 AM

Step 7

All the sketch needs now is a light touch in Photoshop. Eraser tool takes care of all the excess material in the sketch and a little visit in the "Levels" menu takes care of all the possible color left from the scan and adds a bit contrast to the sketch.

I'm strongly against using any kind of digital editing (Photoshop stars / colors / nebulosity) so none is used.

Here is the final version:

Step 7 - The final sketch

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408022 - 10/24/09 11:26 AM

Acknowledgments

Sketching is very rarely this easy. A good sketcher requires endurance and strong will to stay outside for hours just to finish up few sketches. Your hard working sketcher can often be late from school/work, appears red eyed and dead tired in the morning.

Here are some of the typical things I've encountered during my over a decade long sketching career and these are just a few of the things a true sketcher has to endure during sketching:

* Temperatures below -20°C (-4°F)
* High humidity (sketching paper gets soaking wet)
* Stage 1-2 frostbite in your hands/feet
* Steady hands
* Chance of loosing your night's observations in a gust of wind/leaving them to your observing spot

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!

Edited by JakeSaloranta (10/24/09 11:37 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
mapofthedead
super member


Reged: 06/01/06
Posts: 155
Loc: Cambs, UK
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408096 - 10/24/09 12:26 PM

Very interesting in the fact you use an ink pen to "sketch", I have to say, through experience, pencils work better at -20°C than ink

Hands and fingers however, do not

--------------------
You cannot teach a man anything; you can only help him discover it in himself.
-- Galileo Galilei


Post Extras: Print Post   Remind Me!   Notify Moderator  
Waduino
sage


Reged: 10/24/08
Posts: 286
Loc: Richmond Hill, Ontario
Re: How do I do it - Sketching a simple open cluster new [Re: mapofthedead]
      #3408171 - 10/24/09 01:17 PM

Thanks for posting this. And how long would you say it takes to sketch an open cluster, like the one used in the demo?
Wad.


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open cluster new [Re: Waduino]
      #3408287 - 10/24/09 02:13 PM

Quote:

And how long would you say it takes to sketch an open cluster, like the one used in the demo?




I think it took me roughly 30-40 minutes to sketch this one. Very time consuming!

/Jake

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Jef De Wit
Carpal Tunnel


Reged: 03/06/09
Posts: 2234
Loc: Hove, Belgium
Re: How do I do it - Sketching a simple open cluster new [Re: JakeSaloranta]
      #3408406 - 10/24/09 03:23 PM Attachment (86 downloads)

Jake, reading your "way of working" was very interesting. I will think of your "1/3 rule" the next time I sketch a cluster. In the beginning I used more the "1/1 rule"... which gives terrible results. An example to illustrate: NGC 7243 (Caldwell 16). A cluster 30' large in a field of view of 37'!

Attachment

--------------------
Clear skies
Lunt LS35THa, Eden XP 8x42, 6 cm 60's Towa, WO Zenithstar 80 FD & Orion Optics UK 30 cm Dobson
"Bright skies aren't empty skies" (James Mallaney)
My best solar system sketches
My deep sky sketches


Post Extras: Print Post   Remind Me!   Notify Moderator  
DNTash
scholastic sledgehammer


Reged: 09/02/07
Posts: 856
Loc: Berlin, Germany
Re: How do I do it - Sketching a simple open clust new [Re: Jef De Wit]
      #3409233 - 10/25/09 12:49 AM

Thanks for posting your process -- very helpful for those of us just getting started with sketching. Where does one find the ready-made sketch pages with the circular field of view?

--------------------
AT 72ED f/6 doublet
TMB 92L f/5.5 triplet
Orion 120ST f/5


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open clust new [Re: DNTash]
      #3409378 - 10/25/09 04:38 AM

Quote:

Where does one find the ready-made sketch pages with the circular field of view?




I've used our deep sky-section's cardboard sketching template from 1998. I think we just got a new copy of these few months ago and there should be a bunch of them in English too. I'll see if somone has a pdf file.

Here's just a simple circle:


/Jake

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
DNTash
scholastic sledgehammer


Reged: 09/02/07
Posts: 856
Loc: Berlin, Germany
Re: How do I do it - Sketching a simple open clust new [Re: JakeSaloranta]
      #3409391 - 10/25/09 05:20 AM

Thanks Jake, very nice of you! A .pdf in English would be great if you can find one -- love to see it. I'm curious as to what all the data points were on the sheet.

Dale

--------------------
AT 72ED f/6 doublet
TMB 92L f/5.5 triplet
Orion 120ST f/5


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open clust new [Re: DNTash]
      #3409420 - 10/25/09 06:38 AM

Object
RA
Dec
Magnitude
Size
Epoch
Type (of object)

Sketch (date and time)

Observer
Observing place
Instrument
Magnification
Filter
Field of view
Limiting magnitude
Background brightness
Seeing
Visuality (of the object)
Height (of the object)
Weather

Description

---------------------

My personal html template looks something like this:

Instrument: N203/1200mm Orion DSE
Object: NGC 129 / Collinder 2
Obs. place: Kasiniemi, Padasjoki, Finland
Date: 23/24.3.2006, 16.53
Bortle class: 2 (typical truly dark site)
SQM-L reading: 21.82 (zenith)
NE lim. mag: 7.2 (SE - SAO 122725)
Background sky: 2 (M13 easy naked eye)
Seeing: 2 (slight undulation)
Transparency: 1-2 (stars bright near the horizon)
Sky conditions: Slight sky glow in the N (aurora?)
Weather: Good. -14°C, humidity 71%, N wind 3m/s.

Minimum aperture: <7x50 binocs
Visual impressiveness: 1 (excellent)

Description: bla bla bla.

/Jake

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!

Edited by JakeSaloranta (10/25/09 06:43 AM)


Post Extras: Print Post   Remind Me!   Notify Moderator  
DNTash
scholastic sledgehammer


Reged: 09/02/07
Posts: 856
Loc: Berlin, Germany
Re: How do I do it - Sketching a simple open clust new [Re: JakeSaloranta]
      #3409472 - 10/25/09 08:01 AM

Thank you for that list Jake. Much appreciated and helpful. I see now that your original sheet is in what I believe to be Finnish (?). Your personal template is quite thorough on the seeing conditions, which were superb in your example. That must be an incredible site in Finland -- cold, but incredible. My seeing conditions here in the city last night were light polluted, yet fairly good by local standards, but laughable by comparison to the site in your example. Not sure how I'd fill out your template.

Thanks again, and continued clear skies...

Dale

--------------------
AT 72ED f/6 doublet
TMB 92L f/5.5 triplet
Orion 120ST f/5


Post Extras: Print Post   Remind Me!   Notify Moderator  
JakeSaloranta
scholastic sledgehammer


Reged: 09/18/08
Posts: 967
Loc: Sisu Sauna Sibelius
Re: How do I do it - Sketching a simple open clust new [Re: DNTash]
      #3409497 - 10/25/09 08:28 AM

Dale,

Yes the original sheet is in Finnish.

Regarding good seeing conditions in Finland - it happens very rarely. Dark skies but often sea level (bad) seeing.

/Jake

--------------------
8" Orion DSE
4.7 inch (F/6) Sky-Watcher "Pepe"
3" Konus

The sea was angry that day my friends, like an old man trying to return soup at a deli!


Post Extras: Print Post   Remind Me!   Notify Moderator  
markseibold
Pooh-Bah


Reged: 01/19/08
Posts: 1493
Loc: Portland Oregon
Re: How do I do it - Sketching a simple open clust new [Re: JakeSaloranta]
      #3410351 - 10/25/09 04:19 PM

Jake

Very nice tutorial I have never been able to bring myself to do just stars only. I will have to try it one day. I still have the Omega Centauri globular in my mind after seeing it in Fiji through a 10.1 Newtonian for several hours one night. As you mentioned cold temps, it was a balmy 80 degrees F at 2 AM in Fiji, so I had no excuse not to sketch; I even bought a pastel chalk or two while there; incidentally they are not impervious to temperature, just a little to humidity [especially the paper.]

I see you indicated two hours to for this sketch. Can you imagine the whole moon in 4 ~ 5 hours? It is an extremely fatiguing process to say the least.

I look forward to seeing your future observations and sketches,

Mark

www.markseibold.com
My CN Gallery


Post Extras: Print Post   Remind Me!   Notify Moderator  
kraterkid
Post Laureate


Reged: 03/07/05
Posts: 4709
Loc: Jacumba, California
Re: How do I do it - Sketching a simple open clust new [Re: markseibold]
      #3411433 - 10/26/09 08:45 AM

Super sketch and wonderful description of your technique Jake. I really like the sketch form, it is very easy to read and contains all the pertinent info I'd want, including the equipment, conditions and observation notes. Another fine tutorial for the Best of The Sketching Forum!

--------------------
Rich



My CN Gallery




Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | (show all)


Extra information
0 registered and 60 anonymous users are browsing this forum.

Moderator:  Charlie Hein, cildarith 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 3082

Jump to

CN Forums Home



Cloudy Nights Sponsor: Astronomics