Lacerta f4 250/1000 carbon fibre scope on a Skywatcher AZ-EQ6 pro mount, users experience please - Forums

Topic starter

Jul 12, 2021

I have the Skywatcher f5 8" Newtonian with an AZ-EQ6 pro mount on a Skywatcher pillar, which I am very pleased with and I am thinking of buying the Lacerta 250/1000 f4 carbon fibre scope instead to reduce imaging time. I see that a number of people use this combination and I am interested in users experience. In particular, how does the mount cope with the weight, how easy is it to collimate being an f4, does the secondary mist up or are users using the secondary heater and if so do the wires cause optical problems? Has anyone tried fitting a main mirror fan to keep condensation off the secondary? Thanks for any help as it is quite an investment.

regards,

Moorefam

Engaging

CCDMike

Jul 12, 2021

Hi Moorefam,

I use a Skywatcher 10" Carbon Fibre on a EQ6-R. Does that count?

Best
Mike

David Moore

Topic starter

Jul 13, 2021

Hi Moorefam,

I use a Skywatcher 10" Carbon Fibre on a EQ6-R. Does that count?

Best
Mike

It would help if only they were available still but Skywatcher no longer make them. I'd be interested in your view of the combination though and the weight of the scope.

regards,

Moorefam

Luca Marinelli

Jul 13, 2021

Moorefam,

I image with a TS ONTC 10in f4 scope, very similar design to the Lacerta and presumably close in size and weight. I would be wary of putting this scope on a EQ6R mount. I used to own the mount and imaged with an FSQ106 on it with good success. The 10in f4 reflector is a big sail and you will be tossing a large number of subs on the EQ6 mount. Any amount of wind will make this setup unstable.

I used to image with the ONTC scope on a AP Mach1 and it did reasonably well. Wind tolerance wasn't great but in calm conditions the mount carried it well and it tracked to give tight and round stars. I then moved the scope inside an observatory on a AP1100 mount and performance improved dramatically. I can now image in fairly windy conditions and subs are extremely consistent.

The ONTC with all the imaging gear, TeleVue Paracorr Type 2, and a Pegasus Ultimate Powerbox tips the scale at just around 40lbs.

I use primary and secondary mirror dew heaters (Kendrick). The secondary mirror heater is almost a necessity, even with a dew shield. The primary mirror one is only necessary in the dewiest of nights. Both run at very low power, just enough to keep moisture from condensing on the reflective surfaces. Same for frost in the Winter.

Best,

Luca

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CCDMike

Jul 14, 2021

Hi Moorefam,

I use a Skywatcher 10" Carbon Fibre on a EQ6-R. Does that count?

Best
Mike

It would help if only they were available still but Skywatcher no longer make them. I'd be interested in your view of the combination though and the weight of the scope.

regards,

Moorefam

That is correct, but the weight should be almost the same and I have no problems with it, as many others here with similar setup.
Of course wind could be a problem, but I have not often to fight with it here.

I would definitely suggest a dew shield as a minimum requirement, or better to heat the secondary. I would not suggest a fan, as it brings more con's (cable, weight...) as pro's. I put the scope out a few hours before the session and as long as the temp does not drop many degrees, this works well enough.

Hope that helps!
Have a good time
Mike

David Moore

Topic starter

Jul 15, 2021

Thanks for the replies

Christoph Zechner

Jul 15, 2021

I have been using the Lacerta 250/1000 on an AZ-EQ6 for a few years now and I am still perfectly happy the carbon tube has almost no temperature movement. Weight is no problem on the AZ-EQ6. I have even tried a dual setup with a Skywatcher 120 ED - but that was too heavy. Collimation is allways a topic with fast Newtons - I am using different tools (Concenter, laser) to have everything aligned. Dew or condensation has never been a problem, but that depends more on your location and weather conditions.

See examples taken with the above setup on my astrobin page: https://www.astrobin.com/users/Fronk/

CS and greetings from Vienna, Austria, Christoph

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David Moore

Topic starter

Jul 15, 2021

Christoph,
Thanks for replying and your comments are helpful. I am interested in what you said about collimation. I have just collimated my Skywatcher 200/1000 f5 Newtonian and it takes me about 3 minutes with a Cheshire eyepiece and it is easy. I have 2 circles to align one within another and I flex the secondary vanes to move one of the spots a little as it is hidden inside a slightly bigger spot. I couldn't align it more accurately if I wanted to. How long does it take you to collimate and how difficult is it please? I don't want o increase setup time as one of my main ideas to get the F4 is to get more image data in the same time as before.

Regards,

David in south Devon UK.

Christoph Zechner

Jul 16, 2021

Hello David

Since I have a more stationary setup (I just push out the whole thing resting on a dolly), I collimate with Chesire, Concenter and Laser only once in a while. First I check, if the secondary mirror is centered. This is the case, when the laser hits the center mark on the main mirror., Then I adjust the main mirror, so the laser reflects itself back. There is a great tutorial here, unfortunatly only in german - but maybe google translate can help: bxAhX5hv0HHYYfDBAQFnoECAcQAA&url=https%3A%2F%2Fteleskop-austria.at%2Finformation%2Fpdf%2FFN25010c_Photonewton_Justage_Primer.pdf&usg=AOvVaw2z7kbnGPflYJrMR_R1B3Wf">Newton primer

Before each imaging session, I do a quick collimation check on a bright star, by going out of focus. You then can easily see, if you have any distortion or egg shaped stars.

CS Christoph

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David Moore

Topic starter

Jul 16, 2021

Thanks CS that's useful