Question about my 70ED

[iksobarg]

Guys,

I just picked up a used TS70ED http://www.365astronomy.com/ts-ined-apo-70420mm-carbon-fiber-tube-2-micro-crayford-focuser-p-2561.html

Its the OTA, focuser and a 2" to 1.25" adapter.

It's my very first, thanks!

But I have a question:

I've never handled one of these before and tried both 6mm and 10 - 1.25 EPs on the 1.25" adapter and tried to focus off to the mountains but got zilch...

I'll try again tonight into the sky.

Anyway for AP what else beside this am I going to need?

http://www.teleskop-express.de/shop/product_info.php/language/en/info/p593_TS-Adapter-from-2--to-male-T-2-with-40mm-optical-length.html

help :0) thanks TEAM!!

[nmoushon]

Firstly try putting in a diagonal and see if that helps. It will add a bit of travel distants and mit help you get focus. The other thing it could be is that with those EPs you are exceeding the mag limit of your telescope. So you will never be able to achieve perfect crisp focus with EPs of that mag. I know with my ED80 my 6mm EP is just a bit too much. I can't achieve crisp focus on jupiter with. Its decent focus and usually my seeing is worse but I know if I put my 2x barlow with it it definately cant achieve focus. So if the diagonal doesnt help then you'll need to get some EPs with less mag. Like 15mm+. I think with the diagonal you should be able to get the 10mm to focus but I think the 6mm mite be a bit to much.

[ronin]

Don't you need a diagonal in the focuser to get the correct optical path length?

[Carina Lass]

Yup, you definitely need the diagonal in it - it's a 450 focal length and only 305 without the diagonal.

There should be a spacer or diagonal inthe box with it - if it's not there, ask for it - it's part of the kit

[andrew63]

Looking at the add there is no diagonal in the kit - which is a bit strange as it will not come to focus without one. This is the sort of thing you need for visual use. Nice telescope - should give some great expansive views though

Opticron 2" Dielectric Diagonal - First Light Optics

andrew

[Chris]

These INED70's are usually sold as the optical tube only plus case, I see they have blurred the diagonal the the red dot finder on the image in the link to show this, therefore you will need a diagonal.

For imaging you will need a t-ring for your DSLR, a field flattener (Altair do a good cheap one). If you don't have a field flattener you may need a spacer to enable anough back focus if memory serves but I'm happy to be corrected on this

Cheers

Chris

[Ludd]

That's a very nice little scope, it will give very clear crisp views of a range of objects.  I have a white-tubed version and I've had good views of planets with a 6mm eyepiece.  I even have a 3.2mm eyepiece which is really pushing it, but it gives reasonable views. The best views I have had were with an 18mm BST eyepiece, sitting in a William Optics diagonal.

I've taken a few photos with the skywatcher field flattener (which has a t-thread built into it) but for anything other than the moon I have had the scope sitting on a very solid GP-DX mount with drives so I can do unguided exposures of about a minute with no trailing.

[iksobarg]

Many thanks for your quick responses.

I got the TS70ED for 288 Euros and it came with only the tube, focusser and case.

I've got a Celestron 1.25" star diagonal ($20) on the way. Could be a week though.. boo...

The TSFA240 T-2 adapter (29 Euros) is also on it's way.

Did someone mention that I'll need a spacer? Sorry, but I need to know what size, provide link, please.

You guys are golden, thank you!

John

[nmoushon]

You will want at least the field flattener. This should provide enough extra length to act as a spacer. Though not sure if one would be needed in the first place but either way (spacer or FF) you should be able to achieve focus with your DSLR.

[r3i]

Hi John,

I've got the white tubed Ian King version and like the TS it was supplied with just the case.  If you're just using it for visual then you shouldn't need a spacer, the diagonal should be enough to achieve focus.

Enjoy your new scope.

[iksobarg]

A reliable source informed me that with a cropped sensor dslr I should not need a FF. I hope this is true. He said I might experience some elongation along the borders but most of the center should be acceptable.

I was relieved just now thinking (hoping) I had shelled out the last necessary 50 Euros for the little extras (diagonal + t2 adapter) to get going on this little starter set.

Ludd, would you share a pic of your white model 70ED?

Thanks to all!

John

[iksobarg]

Oh, btw, what would a hyperion (I'm aware they come in various sizes) function in observing?

How about EP projection adapters? Are they worthwhile?

[r3i]

A reliable source informed me that with a cropped sensor dslr I should not need a FF. I hope this is true. He said I might experience some elongation along the borders but most of the center should be acceptable.

It's been a while since I've taken any images through mine with my QHY8, which has an APS-C sized chip, but I do recall that curvature was very much evident without a flattener.  I've recently been using it my SXV-H9 which has a lot smaller chip and the frame with that camera is flat enough for me without the addition of a flattener.

[iksobarg]

R3i,

Thanks for the food for thought.

I'll keep a side budget for the FF.

Back to :

Experience with Hyperions?

EP projection adapters?

[Chris]

Hi, for imaging you would only need the spacer if you don't get a flattener but I would recommend a flattener to be honest unless you are using a tiny sensor, Skywatcher and Altair both do one for around 70 pounds

Chris

[Alien 13]

The scope when used for AP will require a 2inch extender if you are not using a FF/FR this will allow focus to be achieved with a reasonable amount of focus tube extension, you could use T spacers for this or a dedicated camera adapter like this http://www.firstlightoptics.com/adaptors/skywatcher-2-inch-t-adapter.html.

Alan

[nmoushon]

DSLRs tend to have large sensors and thus you will very much see the elongated stars. I bet you will have to crop about half your image to get them out. I strongly suggest getting the flattener. This will eliminate the need for the spacer so that cost can go straight to the FF.

[iksobarg]

Thanks for your feedback, guys.

I know its been explained here and elsewhere but I still don't understand why a lens doesn't come with this integrated or built-in. It's just a little cruel.

Would a different brand such as an astrotech($150) do the job. Their website says the AT-FF is compatible with other OTAs with f6 / plus what are/is TMB? https://www.astronomics.com/astro-tech-2-inch-field-flattener-astro-tech-tmb-refractors_p17393.aspx

They however have a waiting list.

I spose Orion might work?

http://www.telescope.com/catalog/product.jsp?productId=99608&utm_source=channeladvisor&utm_medium=cse&utm_campaign=Channel%2Badvisor&CA_6C15C=826676007

So I get the point, guys, thanks. FF. I'll make it happen.

[Chris]

Hi Iksobarg, I think the reason most scopes don't have an integrated field flattening element is because of expense and that it wouldn't be as much of an issue for visual work compared to imaging. You can buy Petzval design scopes with a field flattener element built in, the one that springs to mind is the William Optics 66 semi apo Petzval.

Chris

[Ludd]

Belatedly, here are some shots of my white-tubed version, supplied by Bern at Modern Astronomy the morning before I flew out to NZ in 2010.

That objective looks really dirty in this photo!

[iksobarg]

THanks for sharing your pics, Ludd.

The t2 adapter http://www.teleskop-express.de/shop/product_info.php/language/en/info/p593_TS-Adapter-from-2--to-male-T-2-with-40mm-optical-length.html arrived today.

aaand of course it's been a bit cloudy now.

I managed a nothing special moon shot last night:

(I'll have to get the hang of the focusing, this pic was rushed between clouds)

I'm sooo looking forward to some imaging with this real scope. My efforts with the 200mmF4 were a total failure as I could not get anything near pinpoints.

Thanks for your support, gents.

[Alien 13]

That setup should make a very nice daytime telephoto lens too i use mine for both.

Alan

[iksobarg]

Can my friends recommend some filters and other goodies?

[iksobarg]

Does anyone object to this FF? http://www.telescope.com/catalog/product.jsp?productId=99608&utm_source=channeladvisor&utm_medium=cse&utm_campaign=Channel%2Badvisor&CA_6C15C=826676007

Orion ofc said it will still suit my 380mm FL.