Log in

View Full Version here: : Made A Visit To Company 7 To Look At An Eight Inch Dob


refractordude
04-06-2024, 11:18 AM
Hello there


I am about an hour drive from the famous retail shop. It was really interesting and a joy to view so many scopes of different sizes and styles. My main interest was an eight inch Dob. Since my club canceled a few parties and or I could not attend this visit helped my decision. To me an eight inch Dob is kinda bulky. The six inch Dob looked more to my liking. I will lose a half a magnitude of reach with the six, but it is what I am comfortable with carrying. A two hour drive from home will put me under Bortle dark green skies. A three hours drive and I am under Bortle blue skies. The driving is a joy to me as West Virginia is very green and beautiful.


My six inch f8 refractor has a small chip on the edge of the lens. When looking through it I notice a very small diffraction at the edge. However, it does not distract from the view. At home I use a four inch aperture mask for the planets and Moon which blocks the tiny chip. Most of my observations are with my 20x80 binoculars and I use the refractor to get closer/larger image. It is strange but my 80mm binoculars are just as bright as the six inch refractor. I my get the six inch Dob because the refractor with the SkyTee 2 mount, and extension tube is a bit heavy/industrial. Really would be happy with a lite set up and break down for my darksite. However, I may upgrade to 20x100 binoculars and continue with the frac at my darksite. It is not like I have to left and set up the refractor everyday of the week. May get the Dob this week are the 20x100 binoculars a few months from now. Will let you know.


By the way this afternoon I pulled the trigger on a Celestron 80LCM goto. I will attach my ST80 to the mount which will make finding objects a lot easier. Will appreciate your help with the SkyAlign system. It should be here Friday.

https://www.youtube.com/watch?v=FRh4GI25RW4

Saturnine
04-06-2024, 12:55 PM
Hi, with the clamshell chip in the 6" refractor lens, instead of masking and therefore reducing the aperture, it is worthwhile blackening the chip with a black felt pen. It will show as a gap in the diffraction pattern in out of focus star testing but because it is blacked out and wont allow light throughput, you wont get the "small diffraction" you mention when observing and will still get the benefit of the full 6" aperture. I have a 5" f8 frac , with a chip in the lens ( don't ask ) and just blacked it out and the scope works fine for visual
I would also still prefer the 8" dob over the 6" , will go that bit deeper in magnitude and resolving and magnification and really is not that much bigger to carry / transport. I've previously had both so am aware of what is involved. Enjoy your purchases, don't know anything about sky Align though so can't help you there.

refractordude
05-06-2024, 03:22 AM
Saturnine


Thanks for your reply especially the advice on the 6 incher.