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#1 aatt

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Posted 28 February 2013 - 08:27 PM

I have made the leap to larger aperture-6"-15". I have been pleasantly surprised (and a little incredulous) by the number of galaxies I am stumbling across.SO I thought this might be a fun or perhaps vexing question to ask-What is the maximum number of galaxies that you have seen in the FOV at one time?
I am hoping my tally will increase as I get better at picking them out. Right now-8 at once (that I am certain of) somewhere around the Cor Caroli area using a 2" 34mm EP.It has been great fun (even from an orange zone) to just slowly sweep and stop through Ursa Major, Leo and Virgo to see what pops up!

#2 David Knisely

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Posted 01 March 2013 - 01:45 AM

I have made the leap to larger aperture-6"-15". I have been pleasantly surprised (and a little incredulous) by the number of galaxies I am stumbling across.SO I thought this might be a fun or perhaps vexing question to ask-What is the maximum number of galaxies that you have seen in the FOV at one time?
I am hoping my tally will increase as I get better at picking them out. Right now-8 at once (that I am certain of) somewhere around the Cor Caroli area using a 2" 34mm EP.It has been great fun (even from an orange zone) to just slowly sweep and stop through Ursa Major, Leo and Virgo to see what pops up!


It depends on the aperture and things like magnification, sky condition, and other things. In my 10 inch f/5.6 Newtonian from my dark sky site, when I am centered on the lower Markarian Chain in Virgo just east of M86, I can count 13 galaxies at 101x in a field that is about a degree wide (14mm ES100 eyepiece). In the Perseus galaxy cluster (Abell 426), in my 14 inch f/4.6 Newtonian, at 135x using that same 14mm ES100 eye0piece, I can see around 35 to 40 galaxies in its 44.7 arc minute true field of view, although many are quite faint and nearly stellar in appearance. In the giant Coma Berenices Galaxy Cluster (Abell 1656), the number visible in that same 44.7 arc minute field can approach 100 or maybe a few more, although again, many are quite tiny and faint. Clear skies to you.

#3 Tony Flanders

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Posted 01 March 2013 - 08:28 AM

What is the maximum number of galaxies that you have seen in the FOV at one time?


Hard to say. The two most obvious fields for doing this are Markarian's Chain and the Coma Galaxy Cluster, Abell 1656.

Problem is that while my lowest-power eyepiece fits all of Abell 1656 in a single field of view, I need higher magnification to see more than the two brightest galaxies in that cluster. But I'm sure I can see more than a dozen in a single field of view at 114X in my 12.5-inch Dob. Maybe two dozen.

Dark skies and ultrawide-field eyepieces will make a big difference in this department.

#4 rinalmj

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Posted 01 March 2013 - 09:24 AM

My current record is an unimpressive 3 (the Leo Triplet - the view itself was impressive though); however I just made an aperture jump as well, from 8" to 12", and plan to start going to dark sites occassionally, so I'm hoping to improve on my record soon.

On a somewhat related note, I did happen to catch 2 galaxies and a planet in the same field of view last March (M95, M96, and Mars). I don't recall the exact FOV, but it was probably close to 1 degree.

#5 deepskydarrell

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Posted 01 March 2013 - 12:57 PM

What is the maximum number of galaxies that you have seen in the FOV at one time?


Hard to say. The two most obvious fields for doing this are Markarian's Chain and the Coma Galaxy Cluster, Abell 1656.

Problem is that while my lowest-power eyepiece fits all of Abell 1656 in a single field of view, I need higher magnification to see more than the two brightest galaxies in that cluster. But I'm sure I can see more than a dozen in a single field of view at 114X in my 12.5-inch Dob. Maybe two dozen.

Dark skies and ultrawide-field eyepieces will make a big difference in this department.


The crux of the matter?: you increase magnification to see the fainter galaxy cluster members and the field shrinks.

To add to this dilemma I document my observation, recheck the atlas, climb the ladder, change to low power to refind the field that drifted away, get back to my last spot, change out the eyepiece to higher power and then try to remember what the atlas showed to find the next few galaxies in the field. Tracking would be the answer for galaxy cluster work. Then I could just keep changing magnification up and down 'til the galaxy/field count is the highest. Maybe someday I'll have tracking.

DSD.

#6 azure1961p

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Posted 02 March 2013 - 08:27 AM


Problem is that while my lowest-power eyepiece fits all of Abell 1656 in a single field of view, I need higher magnification to see more

Dark skies and ultrawide-field eyepieces will make a big difference in this department.


I find the same. I can SEE many galaxies in a large field of view if I go up in magnification and only study a portion at a time. The final tally can be quite high after all the combined field views . I agree something like a nice 82-100 degree field could make this endeavor realized in a way my plossls simply can't. Oh damn, I just had a wide angle pang.

Pete

#7 Mta472

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Posted 05 March 2013 - 06:14 AM

I live in Oxford, CT ........ also light polluted.
I have a 12 inch Meade LX90 SCT with a focal length of 3048 mm - which limits my FoV to 31 arc minutes.
Max I have seen at once is only 2 or 3 BUT......
2009 was a good year for me : I saw 141 DIFFERENT galaxies from Oxford using my GOTO Meade.
Best astro year I have had yet.

Clear skies.......... mike

#8 zee

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Posted 14 March 2013 - 10:29 PM

twice I've been in dark and clear enough skies to see three at once naked eye, triangulum and andromeda and our own. :)

#9 rinalmj

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Posted 08 April 2013 - 08:57 AM

On Friday I improved my record from 3 to 10 while observing in the Markarian's Chain region. I was using a 24mm 82 degree eyepiece (63X, 1.3 degree FOV). I identified them as M84, M86, NGC4402, NGC4387, NGC4388, NGC4425, NGC4435, NGC4438, NGC4458, and NGC4461.

#10 Dave Mitsky

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Posted 08 April 2013 - 10:49 AM

Here's some information on the Perseus Galaxy Cluster (Abell 426).

http://www.robgendle...lustertext.html

http://www.rc-astro....oto/id1156.html

http://pw2.netcom.co...highe/a426.html

Dave Mitsky

#11 Starman1

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Posted 08 April 2013 - 03:36 PM

I have made the leap to larger aperture-6"-15". I have been pleasantly surprised (and a little incredulous) by the number of galaxies I am stumbling across.SO I thought this might be a fun or perhaps vexing question to ask-What is the maximum number of galaxies that you have seen in the FOV at one time?
I am hoping my tally will increase as I get better at picking them out. Right now-8 at once (that I am certain of) somewhere around the Cor Caroli area using a 2" 34mm EP.It has been great fun (even from an orange zone) to just slowly sweep and stop through Ursa Major, Leo and Virgo to see what pops up!

In my 12.5", around 30. The number is a little vague, since I might have recounted one or two. It was in a 42' field in Abell 426, the large galaxy cluster in Perseus.
In a friend's 32", in a slightly smaller field, we counted 51 (it helped his scope tracked).
In the Virgo cluster, where galaxies are larger and brighter, 8-12 has been my limit for a single 42' field. I could try a slightly lower magnification and larger field, since the galaxies are bright, but there are a lot of small ones in the Virgo Cluster and some magnification brings those out.
In a 15", galaxies are most visible between 150X and 225X, and details better at the higher number.
Assuming your scope is an f/4.5 or so, a 34mm eyepiece is a very low power and large exit pupil for that scope. As such, the sky will be brighter, and the galaxies a lot smaller, that they would be at a higher magnification.
A 15" in dark skies can see upwards of 15-20,000 galaxies, so you will never run out of galaxies to view for the first time.
I call that exciting. Every time I go out, I try to view a number of them I've never seen before, and every time I run into at least one that I kick myself for not having already seen because it is so magnificent and detailed.






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