Best simple Newtonian design software?
Posted 23 November 2012 - 06:46 PM
Posted 23 November 2012 - 11:38 PM
Worked out good.
Posted 24 November 2012 - 08:18 AM
Posted 24 November 2012 - 09:18 AM
Newt isn't very good for some uses.
well that probably has to do with how do you interpret the 75% vignette if I'm recalling correctly.
in the help menu they tell you how to understand it.
so it can be a little confusing if its saying it vignetting and it really doesn't matter.
other than that it's a great schematic layout program.
Posted 24 November 2012 - 10:36 AM
Posted 25 November 2012 - 08:47 AM
Thanks for the feedback!
Posted 26 November 2012 - 10:27 AM
Posted 26 November 2012 - 10:42 AM
Is it that we cannot make any design desisions these days without a computer??
I recently had an experience at work where I felt afterwards, wow the computers are really making the people dumb and lazy, by not letting them think outside their computers.
We had to make a 3d logo of a car company. Our production facility can silhouette cut the logo on a cnc, but how are we going to sculpt the insides to make the logo look like the branding? I couldn't believe the production manager came back with a qoute for molds and other complicated stuff from who knows what company. OMG!
the logo could have been cut on the cnc but some skilled craftsman could have used a hand held belt sander to carve out the scalloped shapes in the logo similair to the back of guitars.
Afterwards I was thinking boy what happened to challenging our craftsman all they do now is push a button and glue and staple.
Posted 26 November 2012 - 10:51 AM
... Is it that we cannot make any design desisions these days without a computer??
I'll get back to you on that in a minute (waiting for the hourglass to go away...).
Posted 27 November 2012 - 06:38 AM
Why do you need software to design a Newtonian, it is such a simple telescope to design that a normal knowlege of the optical principles is surely enough. Finding the diameter of the secondary is also very easy, and you do not need a computer to do this either. Is it that we cannot make any design desisions these days without a computer??
There are several parameters that one can play with when designing/optimizing a Newtonian. A computer allows it do be done quickly.
If you wanted to show how easily it can be done without a computer, you could show the math required to determine the 100% and 75% illuminated fields for a 16 inch F/4.4 Newtonian with 3.1 inch, 3.5 inch and 4 inch secondaries with both low profile and standard profile 2 inch focusers with 17inch, 17.5 inch, 18 inch, and 18.5 inch tube diameters.
When I design, I use the computer as a tool to allow me to look at a variety of choices so I can make a decision based on a number of possible scenarios. Since generally I am designing obscure research equipment, the software does not exist so I write my own but in this case, Newtwin and now Newt for the web are readily available so I take advantage of Dale's efforts.
Posted 27 November 2012 - 10:52 AM
Posted 27 November 2012 - 01:15 PM
this is my favourite software. it´s translated into english. newt is very good also and the results are the same. did this a couple of times for verification of my design parameters.
there are differences regarding the input of the drawtube length.
and then...post the results/screenshot here for an evaluation and discussion.
Posted 27 November 2012 - 02:21 PM
Would also be cool to be able to switch to https:// mode and actually place orders for parts to each company from the software. Now that's simplicity!
Posted 27 November 2012 - 03:02 PM
perhaps someone has a design ready for you.
if you want to calculate it with software by yourself here´s a simplified walk through for -visual- purpose.
one of the basic starting points is the
-the f ratio of your mirror
-100% illuminated fov. depends on your purpose. discuss it here. there´s a tried minimum for your special purpose.
-choose your focuser, medium length to short, the shorter, the bigger the illuminated fov.
-the level of obstruction you want to achieve. the smaller the secondary the smaller the 100% fov in tendency.
-the eyepieces you will use. the height of their focal planes is different. you have to come into focus with all of them. with plössls as a rule of thumb the focal plane is where the field stop is. the shorter the focuser travel the more careful you have to be.
televue -> F
discuss it here or look for specs.
by tendency it means that with the same 100% fov your obstruction can be smaller with a short focuser and a
small tube diameter.
then insert as starting point:
-primary mirror diameter
-focal ratio of your primary
-secondary size of a similiar commercial scope. you find it in the ads/specs.
-tube diameter=mirror diameter +50-60mm (tube currents). minimum should be what a commercial scope has.
-the parameters of the focuser
-the parameters of your eyepieces = take account of the range of different focal planes/ that you come into focus with all of them and that the drawtube doesn´t reach into the light path. of course you can shorten the drawtube if that happens.
this is your raw model.
then play with:
other available secondary mirror sizes
perhaps other focusers
perhaps your tube diameter only if necessary and if you want the lowest obstruction.
until you have the 100% fov and obstruction and perhaps the focuser you wanted. then post the result here for an evaluation. if you do it right it will work out fine and you´ll be proud of what you´ve achieved.
Posted 27 November 2012 - 03:16 PM
Posted 27 November 2012 - 03:34 PM