I'm preparing a review for our local astronomy club, so I'm not going to repeat everything from there here. Let me preface my remarks by confessing that I am a bibliophile and other than easily replaced and relatively low cost books, no books of value are forced to suffer the interminable humidity of our Florida nights.
My summary is:
“Bhavesh Jivan-Kala Parekh has created an indispensable resource for those who comb the night sky in search of deep sky objects. No other resource has the features for deep sky observers that 'A Comprehensive Field Guide to the NGC' contains. This belongs on their table next to their favorite field star atlas.”
I'll also provide an anecdote to illustrate the value of this to me. Recently I was observing and selected M39, an object which until then I'd never viewed. The objective of my session was to re-align my portable mount, so I didn't have an observing plan other than, "Take the Cambridge Star Atlas and see what's cool in Cygnus and adjoining constellations."
Bingo, Don! I'm viewing an object in one of the Summer volumes during the middle of Autumn. I should have brought the volume to the 'Astro-Patio' (see photo below), but I didn't--only the relatively low-cost and easily replaced 'Cambridge Star Atlas'.
I got my mount aligned, bouncing from star-to-star to insure a good alignment, then slewed to M39 but--alas--there was no open cluster there.
OK, time to change eyepieces--let me put the Televue Panoptic 41mm in and find the cluster. Nope, it's still not there. Let me work through some other eyepieces, since this isn't working: 35mm, 21mm, 13mm, and finally 8mm. Where the heck is that cluster!
OK, I'll start a slow circling routine to see how out-of-alignment my mount is. Darn! Still can't find that pesky M39! Let me slew back to it and take another gander. Nope, still not there...so I found other objects to view.
When I finished viewing, got everything battened down, covered, and stowed I went back in the house and I broke out Bhavesh's "must have" (for me) set and--voila!--there it was--M39 in all its underwhelming glory. Little did I know that M39 isn't a typical open cluster. I have Numazawa's work but it is not a field guide and I wouldn't think of subjecting it to a humid Florida night.
Sure, I could have taken Numazawa's book out and found that those stars I was viewing were, indeed, M39. I could have take Stephen James O'Meara's, "Deep-Sky Companions: The Messier Objects" out, but if I got in that habit I'd be buying a new volume every year due to humidity. I could have taken Ronald Stoyan's "Atlas of the Messier Objects: Highlights of the Deep Sky", but at a replacement cost of $890 I really don't think so.
Bhavesh has done us amateur astronomers a huge favor by putting this work together. Is it perfect? No. Would I like stiffer covers? Yes. Would I like something other than plastic coil binding? If it were stiffer than the plastic, yes. Would I be willing to pay the extra $50 to $100 for the set that those changes would make? Yes, but even at the current price see how many people in this thread have said it is beyond their budget. Those improvements would simply make the resource less accessible.
As for turning the set into a PDF or other electronic format, my best guess is that one would be looking a a file that is a gigabyte or more and would be sluggish in the best of PDF viewers. Writing a custom app to swap in and out relevant images and information could trim the memory requirements down, but the cost of the coding would offset the savings from not having a printed volume.
Finally, I'm a tactile guy and like to annotate with pen, pencil, and little sticky notes my resources and references. One simply cannot do that with electronic media.
Thanks again, Bhavesh, for your toil in producing such a magnificent resource!
Edited by KellyMcGrew, 08 November 2020 - 07:05 PM.