Problem with eyepieces less than 25mm

[starman1969]

I'm fairly new to telescopes. I have owned a Celestron 6se for the last 6 months or so, my first scope which I got 2nd hand with loads of extras such as eyepieces, filters etc..

I have been able to see some great detail on the moon with it, also I can see Jupiter quite clearly too.

I only use a 25mm eyepiece with or without a 2x barlow, depending on how close I want to get.

My problem is that when I try any of the smaller eyepieces such as a 10mm, 6mm and a 4mm plossl's which I got with it, all I see is a fuzzy mess.

I can't seem to see anything with these smaller eyepieces. I've tried focusiing but still blurry.

I hope someone may know what the problem might be

[MjrTom]

I suspect its too much power for your seeing conditions

A 10mm eyepiece = 150x magnification

6mm= 250x

4mm= 375x

Seeing conditions, i.e the stability of the atmosphere and the clarity vary greatly.

You should find on better days the 10mm will be usable and on exceptional days the 6mm.

[E621Keith]

What are the design of those 10, 6, 4mm eyepieces?

If they are conventional designs, the eye relief will be a bit short for spectacle wearer. The focal point may be quite different if those eyepieces weren't par focal with your 25mm.

If they are R, H, SR, MA deisgn, then those eyepieces are junk.

I have used my 6SE up to 8mm without problem. Seeing condition will start to affect image quality at higher magnification.

Have you check the collimation of your scope? If the optics are out of collimation, then the image quality will be affected.

[rwilkey]

I think if those shorter focal lengths are plossl's then the eye-relief will be short and difficult to use, but seeing conditions count for a lot, I also agree 4mm too powerful to be of any immediate use.

[starman1969]

What are the design of those 10, 6, 4mm eyepieces?

If they are conventional designs, the eye relief will be a bit short for spectacle wearer. The focal point may be quite different if those eyepieces weren't par focal with your 25mm.

If they are R, H, SR, MA deisgn, then those eyepieces are junk.

I have used my 6SE up to 8mm without problem. Seeing condition will start to affect image quality at higher magnification.

Have you check the collimation of your scope? If the optics are out of collimation, then the image quality will be affected.

Thanks for the replies.

I don't recognise these eyepiece designs.

The 10mm is silver and says plossl 10mm Multi Coated, nothing else.

The 6 and 4mm are both branded Celestron and have plossl Fully Multi Coated on them.

If i can get away with using the 10mm for now I will be happy. I may look at using the higher power ones later.

I will also check the collimation of the scope now that I have just googled it to find out what it means!

I managed a snapshot of Jupiter with it last night.

[michael.h.f.wilkinson]

I had a Celestron Plossl 10mm, and though it was quite sharp I did not like its poor eye relief. The eye relief with the 4 and 6mm will be even worse. One thing to check is collimation. If out of focus stars do not look like nicely symmetrical donuts (in particular in the centre of the field of view), something is wrong. This is not (that) critical at low magnification, much more at high. Look here for more information:

Schmidt Cassegrain telescope advice - maintenance - SCT collimation

[rwilkey]

The 10mm plossl should be useable, just give it a bit of time, plossl's are better than the standard ep's that come with the scope, Silvertops in particular are supposed to be good, but if eye relief is a problem then you would need to be looking elsewhere, there are better out there.

[michael.h.f.wilkinson]

The 10mm plossl should be useable, just give it a bit of time, plossl's are better than the standard ep's that come with the scope, Silvertops in particular are supposed to be good, but if eye relief is a problem then you would need to be looking elsewhere, there are better out there.

My Celestron came with a Plossl (26mm built by Vixen), I believe many still do.