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Jimi Lowrey
March 9th, 2012, 01:54 PM
IC 4107 Is one of the (If not) faintest Galaxies in the NGC IC catalog. SDSS list it at 17.2G Mag 16.4R mag or approx. 16.8 V Mag. It's a very LSB Dwarf not to far from M64 in Coma and was discovered by Max Wolf in JAN 1 1907 photographically. I have been asking if any one has observed it for the last few years on different on line forms and have not had much of a reply.

I know of very few observations of it and was wondering what is the smallest scope it would take to see this ghostly glow? I plane to try with different aperture scopes at the Texas Star Party to see what is the smallest scope to catch it.

This would be a good springtime challenge object and I would like to hear your positive or negative reports! I hope that some of the Deep Sky Hounds on her will sniff this one out and give it a GO. :D
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Uwe Glahn
March 9th, 2012, 08:53 PM
Hi Jimi,

we, Frank Richardsen, Friedl Lampecht and I tried the faint IC galaxy last year with my 27". The sky conditions were nearly perfect - austrian alps, 8400 feet, transparency very good, NELM 7m+, Seeing II

Friedl and I saw a very faint laminar glow but could not hold it with averted vision. But the position was not" clear", something was there - at the border of perception. We were not absolutely sure, but we saw the glow at the exactly same position. Frank was also at the same position, could also not hold the glow, but he estimate the observation as success. All in all we think we got the IC - with more or less difficulties.

I'm also very interested about some more positive or negative reports.

Jimi Lowrey
March 9th, 2012, 10:26 PM
Uwe what power were you using and did you try low power to try and see it.

Your's is the only other observation I have head of. GOOD JOB!

Uwe Glahn
March 10th, 2012, 07:17 AM
Ah, I forgot to imagine the power - we used 366x (1,9mm AP/8mm Ethos). I also tried 172x (4mm AP/17mm Ethos) but with no success.

Steve Gottlieb
March 10th, 2012, 06:53 PM
I'm not sure what source Wolfgang Steinicke used (or just his own estimate), but he claims IC 4107 is the faintest in the IC (certainly nothing in the NGC comes close) with a V mag = 17.9. Add to that, the galaxy has a pretty uniform, extremely low surface brightness and you can see why this is one tough challenge in any size scope.

Last April I logged it as "extremely faint and small, round, ~10" [on the SDSS image, it appears larger], requiring averted vision." Oh yeah, this is with Jimi's 48-inch.

Marko
March 10th, 2012, 11:40 PM
Me thinks me have no stinking chance of seeing this dim, diffuse galaxy in my 18" but it is is an interesting limit case. I wonder if 22 could pull it in on a NELM 6.8 or better sky?

Jim Chandler
March 11th, 2012, 03:24 AM
I wonder if 22 could pull it in on a NELM 6.8 or better sky?

It might happen if you get it to a high enough elevation. Getting above most of the air is critical on these low surface brightness objects.

Jimi Lowrey
March 11th, 2012, 04:03 AM
Steve did we use you're 21 Ethos on IC 4107 I can not remember, I know that I have see it in a 16MM ZAO 305X and a 10MM ZAO 488X.

Steve Gottlieb
March 11th, 2012, 04:53 AM
I'm out of town right now, but will check my original notes when I get home tomorrow. In the meantime, I hope Alvin doesn't mind me posting his notes on IC 4107 at 375x --

48" (375x) – Extremely faint very diffuse round glow. No central brightening. About 0.5’ across. Forms a triangle with a 13.6 mag star 3.2’ ESE and a 14.5 mag star 3.2’ WSW. A very small uncharted galaxy detected 0.7’ north of the 14.5 mag star. This is probably the faintest member of the NGC/IC catalog.