Eyepiece gap?

[bish]

I've got a bit of space in my ep case.  Currently I have a 24mm, 12mm, 8mm, 6.5mm and 2x barlow.  I thought that I must need a 16 or 18mm ep to fill the gap. After giving it some thought I can't remember ever really missing out by not having one in that range.  Currently (with barlow) I get x50 , x100,  x150, x184 , x300. 

An 18mm would give me x66 - which I've never really missed.  Half the time I jump from the 24mm to 8mm , or sometimes straight to the 8mm.  On the other hand there have been times when x184 wasn't quite enough but x300 a bit too much. Perhaps the gap is actually for a 5mm (x240)??

[ronin]

One at the smaller end is likely required.

Mainly because at small end 1mm can make a fair difference.

The 250PX seems to be 1200mm focal length so a 6mm means 200x and a 5mm 240x whereas a 4mm means a jump to 300x.

What to get I would not really like to suggest, a 5mm, 6mm and 7mm would be nice. :grin:

[bish]

One at the smaller end is likely required.

Mainly because at small end 1mm can make a fair difference.

The 250PX seems to be 1200mm focal length so a 6mm means 200x and a 5mm 240x whereas a 4mm means a jump to 300x.

What to get I would not really like to suggest, a 5mm, 6mm and 7mm would be nice. :grin:

Yes  - it certainly would be nice! perhaps I should just get a smaller ep case so it looks full. LOL.   I think I will start with a 5mm.

[Paul73]

5mm will not get much use in your dob. Our skys just aren't good enough except on really good seeing nights. 6mm will get far more use.

I have 5, 6, 8, 12, 16, 20, 24, 30mm's. If I had to cut it back to the minimum, it would be 6, 8, and either 12&20&28 or 16&24&30.

So yes I would fill the gap first.

Paul

[Ags]

Depends on the target... 5mm would be good for Saturn and Mars. I think you need both.

[bish]

Depends on the target... 5mm would be good for Saturn and Mars. I think you need both.

You're probably right.  I think that an 18mm or 5mm would both fill a gap but  just not get so much use as the others.