Affiliation
American Association of Variable Star Observers (AAVSO)
Sat, 07/16/2016 - 16:41
Just been corresponding with an observer who (as I would) wants to see the facility for VSP to produce charts suitable for use on digital devices rather than printed charts, so... red stars on a black BG. Not sure what language VSP uses, but can it (for instance) use API calls or something similar to do this? There seems to be a market for red-on-black!
Some time ago I converted all my 500-odd charts to this format by either scanning into Photoplus or downloading from VSP and then manipulating likewise. It took a while! (British understatement) and it'd be cool if other folks could be spared this trouble.
Call me an 'ole stick in the mud' but in my honest opinion digital devices have no place at the visual observers telescope. Keep 'em well away!
Gary
It's OK Gary, the laptop isn't connected to the scope, or to the observer! I just got fed up with charts blowing about in the wind/mildew/having their ink run when they got damp and other problems not calculated to help one's blood pressure.
PS - you're an ole stick in the mud ;-)
If you want custom colors for your charts, just download the .png files from VSP and change colors using GIMP or Photoshop. I did that for a while, until I noticed how rapidly the toner in my laser printer depleted when I printed them out. Now I print them on light blue paper. Under red light, it works just fine. Yellow paper works also.
Also, I put my charts in those clear plastic jackets that are used for slides (e.g. Avery PHV119). It makes them easier to store in a ring binder without tearing. I'm not trying to start a thread on chart housekeeping, just a thought.
OK - worked out the best of both worlds. I have written a quick 'mask' for my app (v2) that I use at the scope. The physical charts downloaded from VSP remain black on white (so you can print them or use them 'conventionally') but the app routine shows them as red on black. VB6 code is:
picBox.Picture = LoadPicture("c:\aavso\ab cep.gif")
picBox.AutoRedraw = True
With picBox
.DrawMode = vbInvert
picBox.Line (0, 0)-(.ScaleWidth, .ScaleHeight), vbWhite, BF
picBox.DrawMode = vbMaskPen
picBox.Line (0, 0)-(.ScaleWidth, .ScaleHeight), vbRed, BF
End With
In practice of course the picture (i.e., chart) in the picture box is retrieved from a file using code. I just use a B&W chart for AB Cep for testing purposes. Not sure yet whether VB6 understands .png files though.
On that front, one little suggestion to VSP... could the file name bear the name of the star, so "al dra.png" rather than "X16779I.png"?
I use a my own LiveCode program to create red on black charts. See attached - just the right size to fit an iPad screen.
I wonder what the effect is on the eyes looking at an LCD screen in the dark and how it might influence visual estimates. Anyone know anything about this?
I like the idea of making the charts more accessible and easy to use in this way. However, maybe we should know more before we introduce the capability to use AAVSO charts this way. And that might help convince some traditionalists.
FYI, I have a web page where I offer the ten_star_tutorial charts as red on black:
http://go.uis.edu/jmart5/tenstar.nightcharts
Us old fogeys used blue printed charts - white stars - empty spots - against a solid blue printed background. We'd glue the charts - D and F or G scales back to back. They wouldn't get softened as much by the dew and would stay stiffer than a single sheet that got limp as the dew condensed.
A pile of those charts smelled of ammonia. Whatever happened to those old machines?
Lew
When I first joined AAVSO I remember a chart for RS Aur which was one of those old-style blue charts, but a thought - since a lot of observers use a red light source, wouldn't blue appear virtually black in red light? Good idea there!
Okay, the charting/reporting app is coming along, but now I need to get some idea of how users prefer to handle the actual chart picture. At the moment I have two scenarios:
1) Use coding to make charts appear as red stars on black (only appear - the actual chart remains black on white) BUT at reduced size of 600 x 750 pixels.
2) Show the chart at its original size and make it draggable (with attendant flicker) BUT black on white.
The two colour options above are unfortunately mutually exclusive, and in both cases the users will have to do some 'photoshopping' - the VSP charts are .pdf files but you will need to convert them to (preferably) .gif files, since VB6 predates pdf file types. I saved mine as 64-colour gifs and they are just fine. File size is much smaller too, making everything faster. If night-vision is a priority then if you choose option (2) you will need to make the charts red on black. Because of the way the search algorithm works, the chart will have to be named from the variable, so if your VSP chart for (say) SS Cyg is called "abc1234.pdf" it needs to be renamed "ss cyg.gif". Sorry, but that's what happens when you have to have a format that has to cover a wide variety of user solutions!
So - any preferences?