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There are several points here.
For the Mars Section the images submitted are placed in a folder for each observer, and filed by apparition. When it comes to selecting work for publication, I make a point of selecting as wide a range of observers as possible. So I do not always use the best available work submitted by two or three people. If I make one of my collages for a Section report I will try to use a range of good quality work, though the images must show a comparable degree of sharpness and colour balance for aesthetic reasons. If you look at the collages for martian regions I, II and III that will appear in the 2010 Section report in the June Journal (hopefully), you will see I use a lot of different observers. I make a point of counting the number of images from each observer, and if someone has been particularly active, even if they have not achieved the highest resolution, I always try to reward him or her with something in print.
Here is an example of an illustration from 2010, for Region II, and slimmed down to 800 pixels wide. The highest resolution images are at the bottom, while the less high resolution material, both drawings and images (and even an image by me!) are at the top on a slightly smaller scale.
Drawings are mostly submitted by email and are treated in the same manner. Material sent through the post is stored in a number of filing cabinets, and we have records of past observations going back to the early days of BAA history. It would be pleasant to scan some of the older material to make it available online, but the task is a massive one, and not to be undertaken lightly. Planetary drawings cannot be treated in the same way as alphanumeric light estimates of variable stars.
Illustrations in print are often chosen for a specific purpose. If I want to show some phenomenon that not many people saw, for example one of the peculiar high terminator projections at the 2012 opposition, then I will often have to use an image which would not normally be considered good enough for publication.
For the current opposition (2018) you may have spotted that I am writing a narrative with selected images, and updating it every few days. I do not try to upload all submitted images: that would leave me with no time to actually analyse the work properly, and there exist several other organisations that already maintain good online galleries. Other Sections probably upload more current observations to the BAA webpages than I do, but I am more concerned about publishing the work in the Journal at the end of the day, where all members can see it.
We have had several collaborations with professional astronomers, and these are described in my reports.
I have taken a similar line with the observations of the Mercury & Venus Section. The BAA is an association of observers, and not all of them have large telescopes or electronic cameras. I certainly want to encourage all sorts of observation.
I knew Michael for nearly forty years, and as I used to live in Colchester I visited him quite often. But John Vetterlein knew him for an even longer period, going back to when he lived nearby in the 1950s. Together we have written an appreciation of Michael’s life and work for the Journal. Ron Arbour has described his work and personality so eloquently that I won’t add much more here. I observed with Michael on several occasions, both for daytime and nighttime observations, and it was a great pleasure to have assisted him in photographing Hale-Bopp one evening in 1997. He was, as Ron wrote, a perfectionist as an observer and as a technician. A quiet but very friendly and hospitable man who will be sadly missed.
I am posting two solar images by Michael which show (A) a massive limb prominence and (B) some plages around an active sunspot group, taken by Michael with his 152 mm Cooke OG stopped to 100 mm, with a Barlow lens giving a focal length of 4.7 m, and a 0.7 Angstrom Daystar H alpha filter. These scans do not do justice to the originals, which have a resolution better than 2 arcseconds.
David Arditti is quite right about after sales service. I know of one imported Hydrogen alpha scope which had the unusual problem where the image in that waveband became opaque after several years of use. The diagonal part containing the faulty component was returned via the UK supplier to the USA, and a new part obtained gratis. Had this been purchased by the individual I imagine the process may have been considerably more difficult.
I must have missed the original post but the reply by David Basey is spot on. The optical depth is important, given the rather thin atmosphere of Mars. Some types of cloud on Mars, like the north polar spiral clouds, are best seen at the morning terminator, whereas the orographic or mountain clouds are best seen in late afternoon and evening. Just occasionally, when the band of equatorial cloud is at its most dense it can be seen in white light or in RGB composite images. A good example is the recent image of Phil Miles from a few days ago posted in the current observations part of the Mars Section website. In blue light the cloud blots out most of the Syrtis Major at the central meridian but only a trace can be seen in the white light composite. Past observers from 100 years ago rarely used colour filters but by looking for comments upon the faintness or obscuration of the Syrtis on the CM we can infer that the ECB formed every Martian year: for example, Denning in 1903 was surprised to see a belt of white cloud cutting across the south part of the Syrtis. Thus the present informs the past, as it always does… or is it vice versa?
Although I cannot claim to have known Dudley well personally, I well recall visiting his shop in Golders Green before he moved it to the much more convenient Farringdon Road. In the early 1970s for a time there was a huge 8-inch Cooke refractor which somehow had been set up as a window display. I am told it was eventually bought by someone in Saudi Arabia. Later I used just such an instrument at Cambridge and was able to appreciate how good an 8-inch OG can be. I also recall buying an eyepiece holder from Dudley in the mid-1970s and getting him to take it out the back to machine it to fit a flat tube instead of a curved one. He was very quick on the lathe!
Yes, I shall miss that accent. I worked with Colin to help with an exhibition he was doing on the history of Mars exploration, in the year prior to Beagle II (2002) and then provided groundbased support while Beagle II was about to land. By chance (but not unexpectedly for the martian season) a regional dust storm arose in a nearby part of the planet in 2003 December, and caused Colin some anxious moments. Unable to get images from NASA or elsewhere in real time, he did announce that he had ‘phoned up Richard McKim’ for his Mars weather reports! It was easy for me to follow the planet from my garden, and then to give him a call. And of course I received images from around the world to add in to the picture. In the end, we shall never know for certain whether the dust storm or some other factor was the reason for the demise of Beagle II. Colin was a great British scientist and we are definitely the poorer for his untimely passing.
Richard
