A Document On Nebula Filters, And A Book On Astro Sketching

I've always been a huge Fan of the light pollution filters made by Omega Optical (I usually order them from DGM Optics). If interested, check-out This great PDF document (found via the "Mega-Nebula Filter Site" linked to above).

----- I'd like to take this opportunity, to just briefly mention a new must-have book!
I'll write a full Review of it here, for the blog, in the near future. -----
So, just the bare minimum for now:

I'm very happy to report, that Rony De Laet, an amatuer Astronomer who's work I've greatly admired for many years - Has written a book! 'The Casual Sky Observer's Guide'
I bought (the electronic version of) it immediately! And, I simply love it!
I highly recommend it! (Hopefully, Santa Claus will bring me a paper version of the book for Christmas?)

I have been following his impressive, and very inspiring Website for many years...
Besides the fact, that the Author is obviously a binocular fanatic (like me!) -- He also produces amazing and inspiring pencil sketches! Using Binocs, of course!

In a nutshell: What impresses me most, is his minimalist approach in regards to equipment.
He has been able to do all of this, mainly with just two pairs of binoculars. Two pairs, of what many amateur Astronomers might consider modest binocular models. In other words, not "Alpha" model or super-expensive units.
A pair of 8x56's and a pair of 15x70's (along with a SkyWindow mirror mount).
Very inspiring.

It is basically something that I would love to be able to do: Choose just two pairs of binoculars, to be used for any and all observing (and sketching).
In fact, I'm working on doing just that...
I've always seemed to be spending too much time comparing the performance of various binoculars -- Instead of simply investing in two good pairs, and using them (instead of always scrutinizing their optical abilities).

To be continued...

Incidentally, I've noticed that The SkyWindow looks like it's available for order
once again - The Website was undergoing renovations for a while there... 

Clear skies!

VHT Nebula Filters From DGM Optics

The VHT Nebula Filters from DGM Optics - First impressions

Just a short Post, for now.

You can see the full line of (1.25") nebula filters available, from DGM Optics Here Of course, they are also available for 2" eyepieces.

As I mentioned in my previous Post: The pair of Garrett Optical 100mm binoculars were in need of some nebula filters...More specifically, the pair of (stock) 1.25" eyepieces needed filters. And, I wasn't 100% sure which types I would go with, this time around. These binoculars are much larger than any pair I've used before.

I was originally thinking: A pair of (1.25") GCE's (again)... Unless, (I thought to myself) after consulting Dan: He might suggest something different this time? Perhaps NPB's? I was anxious to find out.
Well, I did ask Dan (of DGM Optics [via e-mail]) and he recommended The VHT's. And it made a lot of sense to me. Here's a Link to the Info page, for the various filters.

Here is the transmission curve, from Omega Optical, the manufacturer: 

Also, from Omega Optical's Site regarding The VHT's:

"An excellent Nebula filter for smaller scopes (4-6 inches aperture) where light gathering and throughput are at a premium. It is also quite effective with larger scopes."

I have been very intrigued, with the measured spectral information shown here on DGM's page. The white graph on the lower right is of GCE Filter.

I also can't help wondering exactly what the measured spectral results would be, for my actual filters. That would be neat.

I haven't had many nights of good seeing, in which to thoroughly test them - But so far, the VHT's have been able to boost the contrast, on the few nebulae that I've tried them on.

And, finally, for astrophotographers - Here are some examples of how these filters help when imaging.
You'll see links to some Reviews of DGM nebula filters Here.

I plan to post a short Review of these filters here, in the near future.

Clear skies!

Old film photo - Corona Borealis

Recently found an old film AP pic I took. I'm afraid I don't have a lot of info on this one.
I can tell you it was taken years ago, using Kodak ISO 200 Slide Film, and scanned with an Epson scanner. It may have been taken with a Pentacon Six, Medium Format camera, but again, I'm not sure. I had to significantly reduce it, just to upload it. Orig. size was over 96MB!
Just a random shot of the area near the constellation Corona Borealis (seen on the left-hand-side of the pic).