LtE in CMO #275

From Christophe PELLIER


® . . . . . . . .Date: Thu, 10 July 2003 15:47:04 -0000

Subject: Mars july 10 2003 : poor image with the C14


Hi all, this morning I made another attempt to image Mars with a C14 but it seems that the planet is really too low in my sky for that big diameter. I will keep imaging with the small newtonian !


Best regards,


® . . . . . . . .Date: Fri, 11 July 2003 18:08:46 -0000

Subject: Mars 11 july 2003


Hi everyone : I have observed this morning 30 mn before the arrival of clouds. The transparency was quite low however and the images have suffered a bit from this.




® . . . . . . . .Date: Sat, 12 July 2003 16:43:35 -0000

Subject: Re: RE:Mars 11 july 2003


Dear Masatsugu,

thank you for your e-mail : I hope that you will go on telling me what are your wishes concerning the Mars images and on expressing special requests such these, if needed. Your message reached me half an hour before I started my observations from this morning so I have been able to pay a closer attention to the G and B images. You will tell me if the images look satisfactory to you or not. I don't know if the images show the evening mist, and I see no really morning mist. This morning the seeing was only poor to fair, but I must be able to observe again at least on the two following days. I have rarely seen such a long period of clear nights with generally good seeing, and I did my best to make the most of that - but I will always be curious of remarks, critics or advices from you or anyone.


Yes, maybe the St Christophe will be a kind of help - as this saint is supposed to protect the traveler maybe it will protect my optical trips to the red planet!

There is a question that I would like to ask about the green images, I hope that you will find time to answer on the days to come - there is no hurry.


Are there some kind of informations that are best seen in a G image on Mars? For example if one wants to shoot white clouds in the atmosphere, what can be the utility of the G image in comparison of the B?  I have this in mind since a few days.


I will describe more my observations form this morning when I send the images, later.

My best regards,


® . . . . . . . .Date: Sat, 12 July 2003 22:20:51 -0000

Subject: Mars july 12 2003


Hi all : this morning the seeing went from poor to fair but the webcam finally handled this correctly when the planet was high enough.


Masatsugu : I have followed your advices and tried to get better G and B images. Apart from the two RVB series I made three minutes avi files (instead of 1-2 generally) for the 03 H 27 green image and the 03 H 35 blue image, in order to seriously increase the s/n ratio. The blue filter for the last one was tilted following Okano's idea, it seems that the dark markings are erased a bit more but this is not evident. I don't really know if these two last shots show the evening mist, maybe over Argyre, but I don't really see the presence of the morning mist.


Best wishes


® . . . . . . . .Date: Sun, 13 July 2003 01:04:18 -0000

Subject: Re: RE:Mars july 12 2003


Dear Masatsugu, you can postpone a future message the way you need to do, no problem. I will observe again in a few hours, and I hope that the seeing will be better. Maybe I'll give a try with the W47 with IR-blocking, to see if the white clouds are better seen?

Best wishes,


® . . . . . . . .Date: Mon, 14 July 2003 00:04:04 -0000

Subject: Mars july 13 2003


Hello observers:

this morning the sky was very turbulent, and it worsened again as the planet was getting higher ! So here is only one RVB series; no other data could be obtained.




® . . . . . . . .Date: Tue, 15 July 2003 02:47:53 -0000

Subject: Mars July 14 2003


Hi all, last night the poor seeing suddenly became fair or fairly good. However due to some focusing mistakes the final RGB composite couldn't be obtained! The color image is from the color Toucam. Note that it looks less detailed than the red images with the B&W webcam.


This is certainly the last time some of the Tharsis volcanoes show on my images... until next month ;




® . . . . . . . .Date: Sat, 19 July 2003 00:57:22 -0000

Subject: Mars July 18 2003 - Best Mars so far


Hi everyone: last night the excellent observing conditions and the nearly 20" apparent diameter allowed me to take my best images of the planet so far.


No dust is seen, but the SPC is showing much interesting phenomena. The images show a kind of almost separated segment of the cap, duller, to the left of the image. And, the very bright pointed part of the cap at CM ~ 10° is still there since the previous images taken from Europe over the last week. Could this be the first sights of the "Argenteus Mons"?  I have also added two color images taken with the color ToUcam, for fun.


Best wishes


® . . . . . . . .Date: Sun, 20 July 2003 04:01:34 -0000

 Subject: Mars july 19 2003


Hi all : the conditions were again good to very good on the morning of july 19. Here are the images. The darkened Mare Serpentis looks impressive!


I'm currently observing - images will follow, much later. It tooks much time to process all the movies...




® . . . . . . . .Date: Sun, 20 July 2003 04:14:09 -0000

Subject: About the tilted blue filter


Dear Masatsugu - just a short message about this idea of tilting the blue filter. I have made some tests in visual with a good image displayed on the computer screen, and it appears that the more I tilt my blue filter and the more it lets pass the red wavelengths. Tilted to the maximum, it acts exactly as a magenta filter, transmitting blue and red ! So, I'm afraid that if I tilt it, it might kill the green ghost, but also give birth to a kind of red ghost...


Okano's idea should be tested further I think ; maybe with the blue filter he has this method works well, but it might depend on what blue filter is used...

Best wishes.


® . . . . . . . .Date: Sun, 20 July 2003 22:15:05 -0000

Subject: Re: RE:About the tilted blue filter


Dear Masatsugu,

Thank you for your comments on my images. Indeed, the luck have been with me about the observing conditions since mid-june, I hope it will stay with me a bit longer! You didn't send me these HST images before. They really make clear the problem. On the past few days, I've been thinking a bit about the use of the blue filter. Precisely, as I think that to tilt my B filter isn't maybe a perfect idea (at least with mine), I have been looking for another blue filter, deeper, that could achieve a better separation of B and G. And now you tell me that you're thinking about the B390 filter, so maybe this could be an even better idea?  If you have any advice of what filter would be the best please let me know.

Thank you for giving me Okano's e-mail, indeed I would be very interested in hearing comments from him on this topic. I will write to him. I know most people want to have images of Mars that show the surface details first, of course I'm also willing to make images like that, but I'm getting more and more aware of the interest of the G and B images of Mars, and this is thanks to the quality of the CMO work and your own remarks and advices. I'm really caring about my G and B filters now... For the reasons why I didn't join you sooner, the point is that back in 2001, my equipment was as modest as my enthusiasm for planets was deep. I still observe with the same small instrument, but in 2001 I was "only" making drawings, and with a moderate aperture they didn't show much details. And I didn't even have a scanner to upload my drawings... Of course you could well download my drawings of the past apparitions of Mars from my homepage if you were interested, but the analysis of the 2001 Mars is now over. Most observers in Europe got totally not interested by the planet when the dust started, while this raised again my motivation for observing this almost blank disk at an altitude of only 15° ! And I keep a wonderful record of that - in late july I clearly witnessed Olympus Mons (the other three volcanoes also, but unseparated) as a dark spot, and at least for that night only it was worth staying at the eyepiece all summer long.

I wish you good observations, and to find the time to do all you are wanting to do about Mars...

Best wishes,


® . . . . . . . .Date: Mon, 21 July 2003 16:46:27 -0000

Subject: Mars july 20 2003


Hi all : some images of Mars taken under very fair seeing...


Best wishes,


® . . . . . . . .Date: Wed, 23 July 2003 01:16:58 -0000

Subject: Re: FW:Mars 20th July UT


Dear Masatsugu, thanks for forwarding me M. Valimberti's image. On my images of this morning that show the following areas, it seems that there is no dust at all. Maybe the yellowish haze is a few dust in the atmosphere, or just an incorrect color by the ToUcam ?

Best regards,


® . . . . . . . .Date: Wed, 23 July 2003 01:13:40 -0000

Subject: Mars july 22 2003


Hi all, this morning the seeing was very good (at the end) and the transparency excellent. The planet looks much quiet now. Images at


I will be away for a few days, but please continue to send images and messages.

Best wishes,

Christophe PELLIER (Bruz, Ille-et-Vilaine, France)

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