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Astrophotography and Sketching >> Sketching

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Chopin
Canis Insanus
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Reged: 02/03/05

Loc: In the doghouse.
Sketch tests: scanning vs photographing
      #6190823 - 11/12/13 02:37 PM

So the story goes like this:

Last night I was inspired to begin lunar observing by trying a hand at my very first "official" lunar sketch. After setting up the scope and finishing collimation the clouds moved in and I waited...and waited...and finally put the scope away.

Not to be beaten, I decided to find a suitable photo of lunar section on google images, and proceeded to draw the image in an attempt to work out some basic illustration techniques. I have said it before, including a recent post in one of Uwe's terrific crater sketches, that drawing lunar features is a flat out daunting task for the novice lunar observer.

So after spending over an hour with the sketch, I came away with some mild comfort, and some possible ideas for area of improvement. It is a humble effort, and I see more wrong than right with the drawing, but I decided I'd post the image to share with my fellow CN sketchers.

Then it dawned on me that not long ago I wanted to experiment with finished captures of an image by comparing a scanned copy to a photographed copy. I am fortunate enough to own a quality Canon bed scanner, as well as some very good Canon camera gear. So what began as a failed trip to the telescope last night, has transmogrified into a mildly insightful experiment...that will surely put you all to sleep.

The scanner used is a Canon MP560 set to 300ppi and all values flat (ei, no sharpness or gamma enhancements).

Camera used is a tripod mounted, remotely triggered Canon 1D with mirror lockup enabled and a Canon 70-200 1:4 L at 200mm and f13 (manually focused). Lighting is a mix of daylight through windows and soft overhead lights. Quick note: dust particles are from filthy sensor

I did my best to normalize the "blacks and whites", as well as the mid grey point, but was careful not to change the gamma curve from the respectively captured states. Both images were also desaturated to remove any color cast.

Full image, scanned:


Full image, photographed:


Crater Arzachel, scanned:


Crater Arzachel, photographed:


Other region, scanned:


Other region, photographed:


Test marks, scanned:


Test marks, photographed:



Both of these results certainly work, and are more than adequate for forum posting purposes. A generalized observation notes that the scanned versions all suffer from lower dynamic range. In some circumstances this leads to a slight increase in contrast, which in turn occasionally creates a perceived sharpness increase (ie, the rim of the crater). This limited dynamic range can also be clearly noted in light, fine pencil strokes in the "8H" of the test marks, and in the lower left edge of the open strokes in the "other region" crops. Most obviously noted is the brightening of the peaks of tooth from the illustration grade paper, I estimate to be caused by the hard edged light of the scanner plate. This unfortunately hides the delicate nature of the faintest pencil strokes by overly highlighting the open paper areas, and promoting an artificial increase in contrast.

I will stress that this is a single test, used with one set of imaging instruments. I do believe that the results should be similar with other related gear, though.

I'm not sure how helpful this will be to others, but if it gets anyone's gears turning...you're welcome.


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JeanB
Pooh-Bah


Reged: 07/11/11

Loc: Montreal, Canada
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6191043 - 11/12/13 04:13 PM

Wow! Very interesting study, Jason! It will certainly be useful. I normally scan my sketches with uneven results. I never tried to photograph them as I could not find a suitable lightsource.

BTW this is a terrific sketch of craters!

Thanks for this post!

Jean


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niteskystargazer
Carpal Tunnel
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Reged: 10/05/09

Loc: 41-43'-28" N 87-42'-39" W
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6191051 - 11/12/13 04:17 PM

Jason,

Very good sketches of the Moon .

CS,KLU,

,

Tom


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hbanich
Pooh-Bah
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Reged: 06/17/05

Loc: Portland, Oregon
Re: Sketch tests: scanning vs photographing new [Re: niteskystargazer]
      #6191178 - 11/12/13 05:17 PM

I've also experimented with photographing my sketches because I found that scanning tended to "burn out" details in the darker areas. But then the problem with photography was getting even illumination of the sketch so the background didn't end up with a light to dark gradiant. After a bunch of experimenting I was ready to give up when a I read a suggestion in this forum to use diffuse sunlight. That worked quite well and is my method of choice for my larger drawings now.

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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
Re: Sketch tests: scanning vs photographing new [Re: hbanich]
      #6191448 - 11/12/13 07:42 PM

Jason, you're just plain wrong. You may be humble, but those sketches are far from it. I hope your actual sketches are just as nice, it would make a nice addition to the lunar art in this forum.

Reading your comment, it's clear your well versed in the subject. It's a great point on the hard light illuminating the paper and 'creating contrast.' Which version is more true to the master (which could be you, but I mean the rendering.) I might choose the method that provides the closest match to the actual sketch.

From a purely aesthetic view, I like the scanned version with the slight boost in contrast. But, I may like it for the wrong reasons, especially if it's less true to the original.


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Chopin
Canis Insanus
*****

Reged: 02/03/05

Loc: In the doghouse.
Re: Sketch tests: scanning vs photographing new [Re: Asbytec]
      #6191771 - 11/12/13 10:30 PM

To all, thank you for the comments, both related to the subject and with regards to the compliments.

Jean, as Howard points out diffuse daylight is a terrific way of finding a plentiful and useful light source. Although diffuse sunlight can be effective, I actually prefer cloudy conditions, as in full cloud cover. The cast is beautifully diffuse, and grey to boot. Either will work.


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Chopin
Canis Insanus
*****

Reged: 02/03/05

Loc: In the doghouse.
Re: Sketch tests: scanning vs photographing new [Re: Asbytec]
      #6191795 - 11/12/13 10:42 PM

Quote:

Jason, you're just plain wrong. You may be humble, but those sketches are far from it. I hope your actual sketches are just as nice, it would make a nice addition to the lunar art in this forum.

Reading your comment, it's clear your well versed in the subject. It's a great point on the hard light illuminating the paper and 'creating contrast.' Which version is more true to the master (which could be you, but I mean the rendering.) I might choose the method that provides the closest match to the actual sketch.

From a purely aesthetic view, I like the scanned version with the slight boost in contrast. But, I may like it for the wrong reasons, especially if it's less true to the original.




Again, thank you Norme.

You do bring up a terrific point, and one that I believe must be the decision of the user. I prefer honesty in representation, so for me the photographic version is better because of its accuracy. That said, given the greater dynamic range, the photo allows more latitude for adjustment in post processing. Ultimately, I am nit picking...slightly. The variation between the two images is not exactly colossal, but it exists nonetheless, and it may offer enough reason for a sketcher to choose one over the other. Overall it's a fun experiment that I recommend to anyone unhappy with their current image posting methods.


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Chopin
Canis Insanus
*****

Reged: 02/03/05

Loc: In the doghouse.
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6191810 - 11/12/13 10:48 PM

Oh, and Norme, to answer your indirect question, the photographic version is indeed a more authentic reproduction of the original.

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Asbytec
Guy in a furry hat
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Reged: 08/08/07

Loc: La Union, PI
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6191836 - 11/12/13 11:06 PM

Interesting dilemma, then: stay true to the original or go with the added contrast for aesthetic reasons. When delivering a sketch, it's good to keep the viewer in mind. Often I increase a little contrast on my own sketches so the viewer does not have to work as hard to see the detail as I did. But, I do try to make it close as possible - leaving some difficulty in - trying to stay true to the image. Balancing those aspects seems key. Plus, everyone's monitor is set randomly from one another, so images show up differently. You almost have to make it easy (or easier) for everyone else to see. Really, maybe sketching is a balance between being true as possible and giving the viewer an easier time looking at it.

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stray1
sage


Reged: 09/03/12

Loc: SW Ohio
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6192623 - 11/13/13 12:52 PM

Jason,

These are great! Your skill with a pencil rivals the best of them. As you stated the difference between scan and photo are slight; however, I prefer the photo version. It looks "cleaner" than the scan (barring dust motes on the sensor ). I'm looking specifically at the small crater in the largest; with the scan it has a definite 3d quality to it, but with the photo it jumps out at you like its really "there". Again, this is a great sketch, can't wait to see more!



-stray-


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frank5817
Postmaster
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Reged: 06/13/06

Loc: Illinois
Re: Sketch tests: scanning vs photographing new [Re: stray1]
      #6193468 - 11/13/13 08:38 PM

Jason,

First of all, nice lunar sketching.
Recently I have both scanned and photographed each of my sketches. I sometimes find the photos are better and other times the scans better when compared to the original sketch.
Neither equal the original.

Frank


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stray1
sage


Reged: 09/03/12

Loc: SW Ohio
Re: Sketch tests: scanning vs photographing new [Re: Chopin]
      #6193855 - 11/14/13 01:06 AM Attachment (7 downloads)

Jason,

I was so appreciative of your moon sketch that I decided to emulate (read butcher) your technique. Below is the result of that effort, my personal train wreck for the night (I want my hour back). You'll note that I tried to copy your cross hatch method of shading. Whereas your lines are smooth and deft; skillfully placed making perfect sense; mine are arbitrary, chaotic, lacking form and rhythm.

Don't get me wrong, there are a couple of things that worked...like one or two of the smaller craters...otherwise...BARF !

One thing that I have learned, however, is that I will never try something like this at the EP. NEVER!

Sketch notes: Rendered from a photograph with “artistic” license. Medium is pencil (2B, B, 2H, & HB) on copy paper. Post work in Paint.net (brightness and contrast adjustment as well as gray border shading).

The End,



-stray-

ps- wanna put this on a coffee mug?

Edited by stray1 (11/14/13 01:08 AM)


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mike73
super member


Reged: 05/01/12

Loc: UK Plymouth
Re: Sketch tests: scanning vs photographing new [Re: stray1]
      #6193966 - 11/14/13 04:28 AM

Scanning white pastels on black paper gave me very contrasty images so I've always just used a camera on a tripod using natural light.
The problem with this is the light changes depending on the time of day. I make some very minor editing adjustments to roughly get the images looking similar but to be honest I don't sweat about it too much, for me the important part of sketching is the actual observing, as long as the end result looks acceptable then I'm happy.

You should be able to see what I mean by looking at this page.
http://www.pbase.com/mike73/messier_sketches


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Chopin
Canis Insanus
*****

Reged: 02/03/05

Loc: In the doghouse.
Re: Sketch tests: scanning vs photographing new [Re: stray1]
      #6195133 - 11/14/13 06:11 PM

Quote:

Jason,

I was so appreciative of your moon sketch that I decided to emulate (read butcher) your technique. Below is the result of that effort, my personal train wreck for the night (I want my hour back). You'll note that I tried to copy your cross hatch method of shading. Whereas your lines are smooth and deft; skillfully placed making perfect sense; mine are arbitrary, chaotic, lacking form and rhythm.

Don't get me wrong, there are a couple of things that worked...like one or two of the smaller craters...otherwise...BARF !

One thing that I have learned, however, is that I will never try something like this at the EP. NEVER!

Sketch notes: Rendered from a photograph with “artistic” license. Medium is pencil (2B, B, 2H, & HB) on copy paper. Post work in Paint.net (brightness and contrast adjustment as well as gray border shading).

The End,



-stray-

ps- wanna put this on a coffee mug?




Mark, I really like the sketch! Your hatching technique is actually quite good, and the shadows are finished far better than mine. Forget coffee mug, I think I see t-shirt in your future.


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Chopin
Canis Insanus
*****

Reged: 02/03/05

Loc: In the doghouse.
Re: Sketch tests: scanning vs photographing new [Re: frank5817]
      #6195145 - 11/14/13 06:17 PM

Quote:

Jason,

First of all, nice lunar sketching.
Recently I have both scanned and photographed each of my sketches. I sometimes find the photos are better and other times the scans better when compared to the original sketch.
Neither equal the original.

Frank





Frank, thanks for the kind words.

Regarding which to use, I do think it really comes down to what works best for a given drawing. So I believe your experiences are poignant. I do want to get under some nebulae to do some subtle faint fuzzy sketch work. Something tells me the differences might be more pronounced between the two methods. Time will tell. First I need clear skies.


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