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Sparky Paul
Jan 17, 2003, 02:59 AM
I was struck by the coloring of the Sagitta 900 in that thread... black on the bottom, yellow on top.
I just repainted a Gentle Lady to a black bottom as I'd had problems seeing it.
Flew it a couple days ago and got some good photos, which I've pasted on a cloud photo..
Each smaller image is 75% of the previous.. againat a blue background (standard SoCal sky :D )
all the planes can be seen, if indistinctly for the right images..
in the cloud photo, the topview image although still there to #8 vanishes at image 6.
Black works better. (See Kelly Johnson. :) )

Ollie
Jan 17, 2003, 08:02 AM
Paul,

That's a great illustration.

How did you take and process the images?

Sparky Paul
Jan 17, 2003, 11:00 AM
Ollie, the original photos were taken with a Fuji FinePix 2800... at 1600x1200 resolution, 6x zoom.
Then transferred from the camera to Paint Shop Pro 7. Choosing one of the images as the sky, I took the other and with the "magic wand" tool selected it out of its background and pasted it into the first image to make the pairing. "Mirrored' the top view to get the plane orientation the way I wanted it..
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Using the wand, selected only the plane images, and pasted those into the cloud photo. Each smaller pair was reduced 75% and wanded and pasted until they got too small.
Here's the Gentle Lady bottom image.
These new generation digital cameras with optical zoom ranges >2 are really good for this stuff..
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Right, here's both images at full size..
The right image goes away faster because it is smaller, and it's less easy to seperate from the cloud background also because of the color..

shoe
Jan 17, 2003, 12:07 PM
That's a great idea but I think that the result is a bit skewed due to the size of the original images. The original on the right is clearly smaller that the one on the left. By the third interation you can still see both quite well and the one on the right is MUCH smaller.

BMatthews
Jan 17, 2003, 03:19 PM
Picture problem aside I agree with Sparky about dark colors on the lower sides. The don't need to be black but any of the very dark colors that shadown to near black are the way to go for sure.

The only alternative that I've found is even close is transparent red or, surprisingly enough, blue and green. You wouldn't think that the last two would work but for some reason they seem to stand out quite well. Forget about trans yellow. It just dissapears too easily........ At least that's what my eyes found.

Dark unders and light tops (white seems to work the best) really lets you see what the model's attitude is when low and distant. The alternating dark and white in a turn being very good to catch.

Gary Retterbush
Jan 17, 2003, 04:37 PM
Sparky, as I recall the Aussies did a fairly good test a few years back with real sailplanes and came up with a dark green as the best.

I can assure you of one thing, white as used in most scale birds is NOT the answer! But, I just can't bring myself to spray an ASW27 or Discus or etc anything other than white.

markdrela
Jan 17, 2003, 07:19 PM
Evidently what matters most is intensity contrast, not color. A yellow-bottom glider against a bright blue sky is very difficult to see. But when it flies in front of a bright white cloud, it becomes much more visible, even though the "color contrast" is worse. The intensity contrast improves, and that's what counts. Dark bottom is good.

Also, I've found that it's important for the dark underside to be continuous across the span. A wing with two dark-bottom tip panels and a light-bottom center panel is MUCH less visible than the same wing with a uniformly dark bottom.
Save any bright decorative chordwise stripes for the top. On the bottom they will only degrade visibility.

Daveairway
Jan 17, 2003, 08:20 PM
Originally posted by Sparky Paul
I was struck by the coloring of the Sagitta 900 in that thread... black on the bottom, yellow on top. (snip) Black works better. (See Kelly Johnson. :) ) Hi All,

The dark bottoms really do work well. My Sagitta is actually a very dark blue on the bottom and my BOT is black on the bottom. They are pretty much equal to see in the air.

There are other points about this color scheme that some might not notice from Paul’s picture. One of the primary advantages is that the black stabs give better orientation at very high altitudes. I also cover the moving rudder dark (at the hinge line, not the vertical fin) to match the wings for the same reason.

I tried a little test while looking at Paul’s photo. First, back away from the computer till the planes get very small. Then look away and look back. The dark plane shows flight direction much better. I have also found that when you get distracted and lose sight of your glider (it only happened once ...) that your eyes will locate the dark wings much faster. This color scheme works for bright skies, dark skies, fog, and cloud base. ;)

Happy Landings,
Dave

Kestrel
Jan 17, 2003, 11:10 PM
BMathews,

I agree with your comments. Trans yellow gets lost by itself. However, if you suround it with the dark colors it really glows! One of my models has all of the open bays covered with trans colors. The center panels and a few of the open bays near the tip are red with perhaps 18" of trans yellow inbetween. All of the sheeting is covered with black on the bottom and white on top.

The model has a poly wing, so in a lower alt. turn with a shallow bank, the off side wing tip is white on top and very visible with the closer tip showing the black underside. It really helps when the model is at a distance.

Sparky Paul
Jan 17, 2003, 11:23 PM
Way back when I used to think being able to differentiate between right-left was most important.. but after a lot of flying, it's not.
Top-bottom is most important. Light colored top, dark colored bottom so that when you see the dark image, you know you're looking at the bottom.
VERY important on manuvering airplanes!
Most of my racers are white on top, orange on the bottom.. they don't get more than a few hundred away anyway, so top-bottom is very important for orientation.
My fun flies are usually yellow on top, red or orange on the bottom, with a large white stripe on the bottom, for instant orientation. These planes don't get very far away or very high. Orientation is THE most important feature of the color scheme on one of these!
Scale paint jobs such as the generic all white full-scale glider which isn't controlled from a distance as the model is really should have the model adulterated with something to aid in orientation, however yucky it is scale wise.
White just plain goes away against clouds.
I see a lot of U-2 activity out here. The black ones disappear quicker than the natural metal (typically a U-2 is stripped to natural metal when undergoing depot level maintainence, and flies in that scheme after reassembly. NASA has a couple of mostly U-2s which fly by occassionally) or white ones, due to the reflective nature of the desert. White shows up for many thousands of feet of altitude, above where black is just impossible to discern.
I like transparent yellow on many of my planes because it "glows" when the plane is on the sunside of the flight area. I think the curved top surface acts like a lens to enhance the sunlight thru the covering. But when the plane is at a slant distance and far out, yellow and orange don't help much. That's why I sprayed the GL bottom with black Krylon.
The attached image of my Oly II shows the transparent yellow "glow" and the transparent green as an effective color.

BMatthews
Jan 18, 2003, 12:18 AM
Originally posted by Sparky Paul
...
Top-bottom is most important. Light colored top, dark colored bottom so that when you see the dark image, you know you're looking at the bottom.......

Exactly.... When I fly far from home plate and I'm lower in the sky than I'd like the switch from dark to white when I'm circling in lift (hopefully...:D) is super comforting and a great aid to ensuring that the model doesn't get tossed off on a tangent and winds up doing something I don't know about.

Daemon
Jan 18, 2003, 02:53 AM
Just another ditto here.
I fly everything I own anywhere from 1000 feet below, to a couple thousand feet above me, and light on top, dark on bottom is key to increasing my "speck" altitude and being able to see em against the ground when they're down low above the ground. (I fly from a paraglider launch often and have had to land at the bottom of the mountain a couple times.)

This isn't a thermal ship but it gets plenty of thermalling duty but here's a color scheme designed for MAX visibility in any orientation against almost any background and lighting conditions, with obvious emphasis put on the more common flight modes.
http://www.houseofthud.com/rc/#moth48
Click on the links to the right of the image to see all the various angles. Every color on that thing plays a very important role in the various conditions that things flies (which is ALL conditions).

BTW, someone suggested that yellow against white clouds works. Not in my experience. One of my gliders was yellow on the bottom and the only thing that showed up against sky or clouds at speck altitude where the broad black stripes across the yellow I added later.

Also people will say "ya, but almost every color ends up looking black at altitude", when justifying blue or red on the bottom. What I've found is that yes, they all look dark under the shadow of the wing itself, but they still disappear from view at a lower altitude than the gliders with a true black bottom.

ian

vario
Jan 18, 2003, 09:21 PM
i have what i think to be the best of all worlds,,its clear on top [balsa color],dark on LE ,top and bottom,then brillant transparent for the underside see attached photo;; on a poly glider i had always liked to have the top of the tips a light color ,buy using clear on the top i get both dark and light! works for me


i also just needed an excuse to show off my 900 sagitta!!:D

vario
Jan 18, 2003, 10:14 PM
bottom

vario
Jan 18, 2003, 10:26 PM
again

vario
Jan 18, 2003, 10:29 PM
side veiw,, its funny but from differant angles it can be very light on top ok ill quit now!! thanks vario

Sparky Paul
Jan 18, 2003, 10:48 PM
Originally posted by Gary Retterbush
Sparky, as I recall the Aussies did a fairly good test a few years back with real sailplanes and came up with a dark green as the best.

...
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I recall reading about the Rhodesian AF testing a couple of Canberras for real high altitude work.
The decision was made to go with brown on the bottom.
The comparison test was inconclusive, with some skeptics feeling the test plane wasn't even flying, when it began to leave a contrail, and that's ALL that could be seen!
The conventional painted plane it was formating with was visible from the ground.
Some day I'd like to be a hundred miles north or so and watch a U-2 going north from Palmdale.. generally they're out of sight long before they get to the con layer looking from Palmdale.. all that can be seen is the contrail going up.
EAFB flies a lot of mostly white fighters, which are very visible from 25-35 miles away, when the sky is clear.
B-52 are similarly invisible except for the cons when they're really up there.. black bottoms.
It probably has a lot to do with the ability of the eye to detect motion more so than color.
The new tactical grey overall paint "vanishes" an F-18 sized plane at 5 or so miles, even when you can hear it, and know where it should be.
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I put my eSpiritElite up to "way too high" today.. mostly yellow, and still quite visible against the totally cloudless blue sky.

Vince inTX.
Jan 22, 2003, 12:27 AM
This is my solution to the, lite on top and dark on the bottom color on the nose and color on the stab, recomendations that I got. It is an original design (tounge firmly in cheek). This was the second plane that I have painted this way......see my avitar for number 1. I have been told to put numbers on the tail but I dont want to look like I''m copying the Thunder Birds:D

All in all I can honestly say that it does help with orientation and tracking......not that it has been at spec attitude yet ......but against grey clouds, white coulds, or clear blue sky I dont have any problems with orientation, attitude or finding it should my eyes have to leave it momentarily.

Vince

Vince inTX.
Jan 22, 2003, 12:28 AM
try this again