Posts Made By: Sol Robbins

Hi Doug,

Great sketch. I find that the ability to split or break up albedo features is more or less tied to magnification/image scale.

For example, in my 6" refractor, I get the most detail and contrast at about 375x. At 400x I believe I get a better handle on separating details. At least I think so.

400x doesn't show me more detail in the 6" than at 375x or maybe even 350x, but it gives me a large enough image scale that makes the break up of albedo features seem easier to sort out.

Sol Robbins

Hi Dave,

The Eye has been suprisingly full of much detail. Its positioning the last three nights has shown it off wonderfully. My best ever view was with my newly completed 10" Dob night before last at 353x and 392x.

I haven't sketched during these last 3 outings due to family and friends wanting to get peaks through the scopes. Last night with the 6" refractor, Argyre, Pyrhale Regio and Chryse were picked off by non observer friends quite easily. For me, Aurorea Sinus, Niliacus, Lunae Palus and Boreum Mare were really showing shape as well.

This year has provided the best views ever. Sol Robbins

Hi Bruce,

Great shot. Has roughly the same orientation shown in my 8.27.03 sketch,(attached).

Thanks for sharing, Sol Robbins

Hi Doug,

Great drawings. Sol Robbins

Hi Doug,

Again, many thanks.

I guess I should briefly comment on my Mars sketches. I really try to see if I can observe and sketch any kind of low contrast break up in albedo features. Unfortunately, this tends to get a bit exaggerated in the sketches as I see the contrasted tones being much closer together tonally than what gets finalized on the finished sketches.

A week of clouds is starting to cure my eye strain

Thanks again, Sol Robbins

Hi,

The bright area that precedes Syrtis M. appears about 2x larger here than it does on the actual drawing. Additionally, I draw Mars inside a the 2" black box so here its enlarged. The drawing also appears grainier than the original. I don't really know what to make of this area in terms of what's going on.

I guess what was visually striking this time out was that the sunset limb was quite thick and had a distinct yellow/orange appearance and the sunrise limb was starkly white with/without filter. The brightening preceding Syrtis M. was enhanced and seen only with filtration. The setting used renders Mars as a very lightly tinted red. This 3 peak filter is only letting red, green and blue peaks through. Its that the emphasis is in the red. Lastly, where did the NPH go? I guess its on a different side of the planet

It was a good night in that as it got later, my refractor was showing a good image at 566x. Although there was is big loss of contrast. The 10" was utterly fantastic with its new premium secondary installed and Guan Sheng primary. Its just that right now, I can't get the hang of hand tracking and sketching at the same time.

Thanks, Sol Robbins

Hi Bruce,

Nice images. There is also a bright spot in Hellas as well.

Thanks, Sol Robbins

Hi Doug,

Very nice sketch. You're right about the SPC showing itself more clearly. It looked a bit irregular in shape as well. I really liked how the NPH was showing up.

It seems that the darker features are appearing dimmer or less dark. I don't think its because of the shrinking of Mars' apparent size though and I have no real explanation why this would happen.

Sol Robbins

Hi Dave,

Even though I have looked through high end apos at 3" to 5" in aperture, I have always wondered how well a high end 6" apo performs.

I use a Skywatcher f/8 6" achromat with a Chromacor II. I have windered how well a ' AP, Tak or TMB would compare on planetary detail.

Thanks for your impressions, Sol Robbins

Hi & thanks.

Even though I've never seen the SEB appear as anything other than smooth in CCD images, it almost always appears a little choppy to me.

This is the first observation I've had where the A Ring showed more than one darkened arc. Usually it has just been the Encke Minima appearing as a singular darkened arc feature on each side of the ansae with my 6" refractor. This time there were distinctly two. I don't believe I saw the actual Encke Division.

Now I guess its time to get my Saturn chops down again. One thing about this scope as compared to my 6" refractor is the appearance of Saturn's satellites. All 4 nearby moons were just a pleasure to see so distinctly with Mimas,(the fifth), being much more difficult.

Thanks again, Sol Robbins