[vsnet-chat 5392] Re: (fwd) Re: (fwd) observation of sgrv4641

["Toni Scarmato" <toniscarmato@hotmail.com>]

Dear Berto and all.

> Dear Don and other puzzled readers,
>
> It is very difficult to probe exactly what Toni is doing wrong. But he
> is very much mistaken and he doesn't want to admit it.

I am not in agreement with you. If you demostrate me that I am in error I
not have any difficulty to admit my error.

> There is a  problem in his attitude.

What?

> He has however shown the ability to deduce a
> sensible limiting magnitude for his local conditions.
> Considering Toni is not faking observations......

At least this!!!!!!! But if this is the doubt, I can also not report
observations!!!!!!!!

> 1. To get and study one or more detailed starcharts depicting V4641 Sgr
> in its MW environment. DSS images are suitable and the position
> reference is possibly shown at the VSNET site.
> Rem: V4641 Sgr and GM Sgr are not the same star!

When I am started with the observation of July 5 I Have identified
SGRV4641 with the star GSC 6848:3831 and no with GM Sgr.
Yet, I want to give some detailed regarding the observation of July 13.
I have printed the image taken by Tanabe-san and  the chart from my Megastar
I Have impressed in my mind the triangle beetwen the star GSC 6848:4015
12.9/0.3, that during my observation was visible, SGRV4641 and
GSC 6848:3606 10.9/0.3

Also, I have impressed the triangle beetwen the realtive bright star  (not
reported in my chart) visible in Tanabe-san image close to SGRV4641,
GSC 6848:3882 and GSC 6848:3606

In thsi way in 1 minute of observation I can to look directlly at position
geometrically pointed.

Every minute 10 second of stop.

A good observer know that when the eye return at the ocular the best way to
detect faint objects is the intervall time (about 20-30 second)
before that the eye detect the light of the background sky.

In this way I saw directly the "apparent flares reported"

After, only with the adverted vision is possible to see faint objects.


> 2. To apply the Henden-Summer sequence to that field and select
> preferably blue stars (B-V must be small) but use the V magnitude for
> comparison in visual observing (or the R magnitude for unfiltered CCD
> observations).

> 3. To try and make the observation at the proper position.
>
> 4. Report <12.8v or whatever is applicable.
>
> I hope Toni will try that!


I did this experience observing comets and making estimations of magnitude.


Best Regards,

Toni Scarmato


> Regarding the use of different telescopes: what a luxury Don has.
> I would use the biggest one only and try to monitor faint cataclysmic
> variables, mainly polars and LMXBs..
>
> Re the present state of V4641 Sgr
> Over the weekend I made another CCD run on V4641 Sgr with 10 sec
> exposures. I did so after I noticed it visually at 13.2V, which can be
> considered the treshold brightness between the quiescent and active
> state. The measurements showed V4641 Sgr to be constant around 13.3CR (+
> or - 0.1 / a bit more than the noise). No activity was seen over the
> measurement period of more than 7 hours.
>
> Regards,
>
> Berto Monard
> Bronberg Observatory
>
>
> >>> Taichi Kato <tkato@kusastro.kyoto-u.ac.jp> 07/13/02 07:40AM >>>
> (fwd) Re: (fwd) observation of sgrv4641
>
>    Since this issue is apparently of public interest, and there is no
> decisive interpretation of Toni's reports, I forward this query:
>
> From: xor@beol.net
> Subject: Re: (fwd) observation of sgrv4641
> Date: Sat, 13 Jul 2002 01:30:49 -0400
>
> As a bit of an intro first let me admit I am a newbie to variable star
>
> observing. I do have several years of "normal observing" experience
> though.
> I have had an interest for some time and have been following the VSNET
> list
> to gain some insight. I am starting to learn about how to take
> estimates
> visually and do them correctly. I have access to an AAVSO member here
> locally. (I hope to start submitting observations to the AAVSO and/or
> VSNET
> in the next couple of months. Do you have any idea what he (Toni) is
> doing
> wrong so I do not make the same mistakes? I want to be as accurate as
> one
> can be doing visual verification of variables. I am going to be using
> three
> different telescopes to do this. I have access to a 32-inch, 14-inch
> and an
> 8-inch. Which telescope would be best for what type of variable?
> Eventually
> I will start doing CCD as soon as I am comfortable doing visual.
> Anyway, any
> advice would be helpful.
>
> Don Stevens
> Clear Skies!
> xor@beol.net
>
> Visit an Observatory near you!
> Perkins Observatory, P.O. Box 449, Delaware, OH 43015
> www.perkins-observatory.org
> perkins@cc.owu.edu
>

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