Well, Mars is very small & low in the sky now & I think most people would be really struggling to discern much from it: your description sounds very much like a lot of the seeing we experience when the seeing & elevation is bad as it has been since Xmas, & I think I know a thing or two about planetary imaging!
But that of course doesn't excuse the appearance of the street lamps - the suggestion of looking for another lens of similar size & f/l might be worthwhile...Sheldon here on CN has some good small objectives that he sources from various places only he seems to be able to access, might be worth PM'ing as one suggestion, I've obtained stuff from him & I'm in Australia...
But of course there are "dogs" from all manufacturers & I've made the comment here on CN several times about getting too carried away with notions of all these 1960's etc small refractors being "Holy Grail's" of the telescope-making arts...I've chronicled my efforts with the Royal Astro 4" f10 Newtonian - still not to the stage of knowing whether the primary which I've spent $200Aus getting re-mirrored is actually of the standard many reverently bless RAO scopes with but I at least have a good substitute if it is a dud - but let me tell you bro, whoever positioned & cut out the hole in the ota for the secondary/focuser when this scope was made was either (a) drunk (b) totally incompetent or © bent on some sort of vendetta against the company...it was about 10-15mm out of position & on a small secondary that is horrific - so much for RAO standards..!
My Dai-Ichi Kogaku, who were mainly OM's for other Japanese branded scopes outperforms my Yamamoto SYW, which is no slouch itself...but I actually think it is a lottery with many of the old so-called "classics" tbh..!
I have very good experience with RAO - my R-74 gives fantastic images and if it weren't so big, heavy and troublesome to carry, I wouldn't even look for something smaller. However, the Kenko is much lighter and more convenient - it is very easy to carry and has a very good and convenient mount. If it could be used for something more than a museum exhibit, it would be a great addition to the observation arsenal.
At the moment, Mars is very well visible in Poland - in the evening it was almost 60 ° above the horizon, so it is not the atmospheric dispersion that is responsible for the image distortions. Admittedly, the sky was a bit overcast and the air was restless, so I don't want to make final judgments. However, it did not have the same effect on the pictures given by Vixen 60/900, which I used again as a comparison.The weather is nice since the morning - maybe I'll be able to re-try in clear skies.
It is sympromatic that a very similar situation takes place with the tripod. While in the case of the lens, the glass has probably not been properly annealed, the cheapest, unseasoned wood was used for the production of the tripod. Some of the wooden elements are bent.
I replaced the 710mm in my Kenko with a 700mm and didn't notice any difference in the focuser's length or any problems. I realize your options in Poland are much more limited than in the states but very many 900mm Towas were made, so maybe you can find a good objective from one. I was a Towa doubter but two of mine turned out to be very good. Also, if you find one in another country, shipping for just the lens might not be too costly. I suppose it largely depends on how valuable or how good the rest of the kit is.
I found out yesterday that even my quirky, ancient Towa spotting scope whose image quality I criticized here: https://www.cloudyni...epiece-revolver / gave a much more precise and contrasting image. Towa - please forgive me! :-) I think that I will try to monitor offers in Germany - this model is quite popular there, as well as Weltblick, which I think has the same lens.
Does the "best focus" indoor artificial star test view correspond to what you see outdoors? Or is the indoor view some how better?
Have we ruled out some other problem like the 90 degree diagonal? Any chance we a looking through trees outside? Sorry for seemingly obvious questions.
Unfortunately, yes - the problems with obtaining a precise image of the pinhole in the foil resemble those with the Mars disk - they are of similar angular size.
Of course, I've tried to replace or remove the diagonal, and I've tried a few different eyepieces. I am aware of the bending of the light on the branches along the way and to be honest I could not completely eliminate this influence while observing the street lamps, but I tried to change the position to make sure that it would not improve the situation. When the snow melts and I can safely carry the telescope over longer distances, it will be easier for me. Unfortunately, my passion for gardening is in drastic contradiction to my love for astronomy :-)
Edited by LukaszLu, 20 February 2021 - 07:50 AM.