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Ovi

Can't focus with my 6.5 and 5 mm eyepieces

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Hello! Yesterday I took my telescope out to observe Saturn. The image through the 25mm and 10mm was good, but when I tried the 6.5mm the image was horrible. It was out of focus very much. Is collimation the problem? I can only see one mirror cap through my collimation cap. Based on this picture which mirror needs adjustment? Thanks! 

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You don’t mention what scope you have, but it could just have been the seeing conditions. Things generally start to look worse when you push higher magnification, especially if seeing conditions aren’t great, and the planets are lower down in the murk at the moment too. Depending on your scope also this could also be hindered by your magnification been close to its maximum limit for your scope.

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I have an TS Megastar 150/1400 EQ-3. When I tried those eyepieces, Saturn was quite high. The weather was clear with no clouds. 

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Is this the TS Megastar? If so what you have is a Jones-Bird style reflector with a spherical primary mirror and a corrector lens in the focuser. Unfortunately, this type of telescope is not suited to high magnification viewing. Anecdotal reports would suggest that the limit is found when you have an exit pupil of around 1mm. For a 1400/150 scope this is ~9.33mm so it is not a surprise that 6.5mm and 5mm eyepieces will perform poorly. In addition, in this scope those eyepieces will give magnifications of 215x and 280x. In the UK you could easily find that the atmosphere does not allow this magnification level on some nights, especially with the planets at low altitudes this year. It would not surprise me if this is also a factor in Romania.

With respect to the collimation, is your primary centre spotted? Without a centre spot it will be difficult to tell.

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No it isnt't marked. Btw, now I am on a trip at a mountain small resort. Should I see all 3 mirror clips?

Edited by Ovi

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They should be evenly spaced around the edge so that you see the same amount of each one. I don't know if the corrector lens in your scope will interfere with that in any way. Given that you are on a trip I would avoid collimating it until you are back home and can get the right tools to do so successfully. 

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I got my entire tools set with me and I don't want to miss the dark sky from here since I live in a big city. :)

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