Bintel 12 inch and Eyepiece combination

[anthony.tony]

Hello There I purchased a Bintel 12 inch Dob last year have been having some good viewing sessions with it.4 years ago I purchased some Takahashi eyepieces 5mm-7.5-18mm and a 2x apo barlow lens it has Japan marked on it.I have a collection of chineese eyepieces.2 weeks ago I purchased from Bintel a Panoptic 24mm 1.25 eyepiece it is a beauty good field of view 78 degrees.It show good detail and contrast .what blows me away is when I put it in the Jap. Apo barlow. things like the Sombrero -M61-Cent A-Tarantula-Omega cent.-tuc 47-Jewel box-and a few other galaxies this was the first time I used it with the Barlow .Good contrast and detail considering the seeing was not perfect.I think I have discovered a good Combination.Tony

[markus.a.bergh]

Hello anthony.tony,
Thanks for the info. I have the same 12"Dob (with a different name but comes from the same factory ). My eyepieces are pretty OK but nothing special. My 7mm never seems to give sharp images and Im considering getting a "good" (and therefore expensie) replacement. Maybe a Pentax XW 5mm or something similar.

I've read that you really need to use good eyepieces on these big F5 dobs because the cheaper ones just dont work well at higher magnifications.

Do you think it's worth spending $300 or $400 on a good eyepiece (for this telescope specificly) ? I don't have enough experience to judge this and am worried about not noticing the difference between a $50 and $300 eyepiece.


If so is it only worth while for higher magnification eyepieces or will I notice the difference in quality with a 20mm eyepiece.

Thanks for your help, Makrus.

[Satchmo]

I think the 8mm Orion Stratus ( $179 locally ) or Baader Hyperion are a great choice without breaking the bank.They are basically chinese copies of the Vixen LVW eyepieces ( without the Lanthanum element ) .

If your scope is not well equiliberated and collimated there is only so much a better eyepiece can do. 8mm will show up any mirror issues in better seeing.

Hope this helps.

[rmcpb]

You could also look at the 8mm Burgess Planetary which has a 60 degree FOV and great eye relief.

[anthony.tony]

Hello I've taken it out to Cookamidgera on 3 occassions now nice dark skies just out of Parkes.I am impressed with what I can see in it.Cris Toohey Has been around a lot of Telscopes . I think he has 30 years experience . He Collimated it for me out there We put his Ethos eyepiece in the scope Looked at the flame neb/ m42/ tarantula /Eta car. /Centaraus A/ omega cent. etc. things looked pretty good.He seemed to think it was working pretty well .Thats why I lashed out and bought the Panoptic.24mm It works well in the dob and work well with the 2x barlow.Do you know a good website the shows good instructions for Collimating an F5 dob. What does Equiiberated mean.I am chasing up one of those Laser barlow Collimators from SDM telescopes.reguard's Tony

[anthony.tony]

If you buy a Panoptic eyepiece it will cost you half the price of your Dob.I am happy with the 24mm Panoptic it's agood eyepiece Can you get to some other people with scopes and compare eyepieces.Thats the best thing to do before you lash out and buy.tony.

[erick]

Tony, by saying equilibrated I'm sure Mark is talking about getting your mirror to the same temperature as the air just above it in the tube. Usually this means cooling the mirror (thermal mass, retaining the daytime heat) down to the (usually dropping) air temperature. This is where the fan attached to the end of the scope comes in. Get it on as soon as you are set up. Many leave it running through-out the session, believing that the air movement helps prevent dew formation on the primary and secondary mirrors. Check at high magnification, however, if your particular fan is inducing any vibration affecting the image you are observing. If any, it seems to be minor in most cases.