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8" or 11" How much VISUAL difference?

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#1 haleymon

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Posted 15 October 2005 - 05:40 PM

8" or 11" How much VISUAL difference?

Just Visual not Photography

Is there really "THAT" much difference?

Thanks

#2 sixela

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Posted 15 October 2005 - 05:48 PM

Yes. At least on M51, I saw a lot of difference in the structure between those two scopes.

See e.g. http://clarkvision.c...stro/m51-apert/

That's pretty correct from what I see - at least from a very dark sky. The darker your skies, the more pronounced the difference will be (though the 11" will always show more!).

#3 Don W

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Posted 15 October 2005 - 06:11 PM

There's a big big difference especially on deep sky objects.

#4 Rich N

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Posted 15 October 2005 - 06:22 PM

Yes. A recent example was the Deep Impact event. There were 40 or 50 scopes at a local observing site to see the probe hit the comet. AFAIK, no one that night could see the comet with 8" SCTs. I could see it in my 15" f/4.5 Dob and I could see it in a friend's C11 (11" f/10 SCT). The comet wasn't as bright in the 11" as it was in my 15" but it wasn't difficult to see in the 11".

Rich

#5 Guest_**DONOTDELETE**_*

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Posted 16 October 2005 - 04:24 PM

8" or 11" How much VISUAL difference?

Just Visual not Photography

Is there really "THAT" much difference?

Thanks

Yes, there is. I also set both up at the same time with the NS8 GPS setup with a 6.3 FRC. I get a little wider FOV with the NS8 that way and the NS11 shows dimmer stuff. Sometimes I view through one while the other is slewing. sometimes I have a lot of other parameters changed like the Denk II binoviewrson the NS11. If I had tostay with one.I'd keep the NS11. I keeptoying with selling the NS8, but it has it's uses too. S does my VCixen FL102S and Orion 4" starblaster. They're all fun. :D

#6 Benjamin B

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Posted 17 October 2005 - 01:23 AM

I have had my C11 OTA for 1 month now, not tried it out that much yet, but the first time I saw M13 and M92, wow. And that was from my balcony that are not that dark. With my old LX90 8" I could only see it like a small fuzzy boll. I can now see into the core with no trouble. It´s like small diamonds.

#7 LivingNDixie

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Posted 17 October 2005 - 06:03 PM

The difference is easily noticed as is the increase in bulk and weight that the 11in will have too.

#8 TimD

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Posted 19 October 2005 - 05:08 AM

I sold my C11 and picked up a LX90, although there is a loss in aperture, the portability factor is much nicer with the LX. I am more inclined to transport the LX90 and I have found that my LX90 from a dark sky location is close to my C11 views in the city limits.

#9 norscot

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Posted 19 October 2005 - 01:46 PM

I've got an 8" LX90, a C11, and a C14 OTA: I use both the C's on a CGE mount. Visually the C11 Starbrite shows much more than the LX90 UHTC on any night, but the difference between the C14 and the C11 is in my opinion not so obvious - although the C14 is definitely brighter and this is most noticeable when viewing globulars. On the other hand, the C14 is also a *Word deleted by the CN gnaughties gnomes* of a lot heavier and much more bulky. The CGE1100 is actually very portable, and can be assembled (in the dark) in 15 minutes without any difficulty. The 11" OTA doesn't look much bigger than the 8" OTA, but the 14" looks huge compared with the 11". I try to make sure I'm early enough to get the 14" OTA mounted while it's still daylight! In my opinion the C11 is the perfect compromise SCT: lots of aperture, but still easy to transport and set up.

Regards
Rick

#10 jeffk1965

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Posted 19 October 2005 - 02:22 PM

I am in the process of trading-in my Meade 8" LX200GPS towards a Celestron 11S-ASGT with XLT. I have decided against the CPC11 as the 65lb weight of the scope and fork mount to be too heavy for me while the C11S-ASGT will break down into three parts: a 28lb ota, a 30lb mount, and 33lbs of counterweights. That will be much more manageable for me.

I have looked through several N11s and have found quite an improvement over my 8" on deep sky objects. Globular Clusters show the greatest difference.

jeff

#11 Guest_**DONOTDELETE**_*

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Posted 19 October 2005 - 09:39 PM

I have an 8 inch LX-90 and could hardly see faint objects like M81/M82 at all with it. I then got a C-11 and they are MUCH brighter with it - meaning I can at least see them without using too much imagination. I don't claim to be an expert, but the difference is obvious and worth the extra hassle of setting up the AS-GT C-11.
Dale
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Posted 21 October 2005 - 06:50 PM

My N11 shows more than my N8. Unfortunately, the weight of the 11 results in the 8 getting used a lot more. Also, the 8 seems a bit less sensitive to adverse seeing than the 11. It would be a very painful decision, but if I could only keep one, it would be the 8 because I would get to see more (often).

#13 Guest_**DONOTDELETE**_*

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Posted 24 October 2005 - 02:30 AM

There IS a good bit of difference. Literally, the 40-50 some percent that manufacturers claim. Problem is, there's a lot more weight with the size difference. As an earlier poster remarked, they use their 8 much more often due to this. The best scope is the one you use the most!

That being said, I DID go for the larger scope because I didn't want to lust after more aperture later and figured since I wanted my scope to be THE scope for my next 5-8 years or so, I'd go with the largest I could safely handle by myself. I think it's worth it as I haven't found anything I couldn't see yet, even from my heavily light polluted backyard!

Good luck!

#14 BluewaterObserva

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Posted 24 October 2005 - 12:47 PM

As stated.. The difference is extreme in my opinion bewteen the two sizes.

#15 TK6411

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Posted 24 October 2005 - 01:23 PM

I went with the 8" SCT rather than the larger OTA's for transportation, weight and storage reasons.

Jim

#16 Tim

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Posted 24 October 2005 - 01:24 PM

have you thought about the 9.25 it may be just what you need a little bigger than the 8 and still easy to move compared to the C11.

I know 9.25 is not that much lighter than the c11 but those few pounds do make a difference or get the CGE model if you can.

If you buy the 8 you may find yourself wishing you had more and aperature may eventually make the leap to something bigger.

but then again the scope that gets used the most is the best scope. so maybe size does matter!

Tim..

#17 TK6411

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Posted 24 October 2005 - 04:21 PM

Aperture fever is a disease much like Nagler fever, alcholism and gambling...lol. Seriously at some point for each individual (which varies from person to person) they have to decide where aperture fever must stop...or we all would have 30" Obsession Telescopes. The most important aspect is use...if you find that you will use an 8" scope more than an 11" or larger it makes little sense to get the larger aperture scope if its seldom used. Many don't fully appreciate the enormous weight and size these scopes have. Before getting one I would suggest going to a local scope shop and even more so a local star party and see what these scopes are like first hand. I'm all in favor of bigger apertures but I'm not getting any younger myself and think that the 8" SCT is just about the right size for me to lift and setup without any real struggle. If I was setting up on a perm pier at a real dark sky site then it would be a different story.

Jim

#18 BluewaterObserva

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Posted 24 October 2005 - 04:25 PM

Sure makes the case TK6411 for owning one each a 6", 8", 12.5", a 17.5", and a 30".... Oh wait, I already do...

:)

#19 TK6411

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Posted 24 October 2005 - 04:50 PM

"Sure makes the case TK6411 for owning one each a 6", 8", 12.5", a 17.5", and a 30".... Oh wait, I already do... "

BluewaterObserva, lol, I've been eyeing a C-11...which would require a change of GEM from the LXD75...hmm...will it ever end, Doc?????

Just asking...but which scope gets used the most?

Jim
(member of Aperture Anonomous)

#20 BluewaterObserva

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Posted 24 October 2005 - 04:59 PM

From my back yard the 6" F/5 and 6" F/8 (Which is also my H-Alpha solat setup) get the most use.

In dark sky when not down at my observatory the 12.5" and 30" are tied as my observatory partener and I always observe as a pair.

The 17.5" EQ is mounted down at the observatory, so not quite 1 weekend per month. The 30" will be EQ mounted and take over most observatory duties next summer, so the 17.5" EQ will be my / our haul around to observing sessions scope.

#21 jeffk1965

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Posted 26 October 2005 - 05:39 PM

Does anyone here have the C11 on the ASGT mount? I was wondering how difficult it is to put the scope on the mount?

Jeff

#22 darylf96

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Posted 28 October 2005 - 01:33 AM

If you have access to dark skies, there is a substantial difference. If you are mostly viewing from a location like mine, the additional cost might not be justified. The loss of contrast might be enough to offset the gain in detail. The other factor is your mount. If you need to put the 11 inch on a CG5 type mount, you may find that the additional aprerture is not so desirable.


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