First Light: Astro Professional 102ED

[RichieJarvis]

As some of you know, the original 102ED that I had exhibited some worrying artifacts when imaging. I am pleased to report that Richard Best of South Downs Astronomy did an excellent job, and had the scope switched out, despite it being reduced as shop-soiled. The replacement unit arrived today with the following notes from the Astro Professional distributor:

We changed the optics and made a star test, even we changed the focuser and the case against a much better version 2

I am very happy to report that the Astro Professional 102ED has seen first light tonight, and was kept free from dew by my new 'blinky' dew heater

These 2 images through the AP 102ED using an SXV-H9 and an Ha filter on Gamma Cassiopeia - the exposure was 0.5 seconds.

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As you can hopefully see, the image artifacts have gone, and the disk edges are clean. This is much more like it!

Visually, stars look crisp and clean, with beautiful colours.

I then focused the scope on Gamma Cassiopeia, with the resulting image. Maxim recorded a FWHM value of 1.67 through the Ha filter for a 0.5 second exposure.

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Focusing was a joy with the new focus unit - its a dual speed 1/10 unit, and feels very well engineered. Bringing the FWHM values down was a very easy task with this unit.

I then swung the scope round to have a go at my favourite target of the moment - NGC7635, the Bubble Nebula. Here is a single 20 minute Ha sub - as you can see, the scope is producing a nice flat field with the SXV-H9, and the contrast is excellent. This image has been stretched to show the nebulousity in the Bubble - no other processing has been applied.

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I ended up taking 3 x 20 second exposures in Ha, and 3 x 20 second exposures in OIII, to produce the image below:

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Conclusion: Astro Professional have produced a lovely 4" scope here, easy to focus, easy to use for imaging, nice for visual use.

[A McEwan]

Very nice images, and that sounds like great customer service! Neat!

[philsail1]

Beautiful image there Ritchie.

Sounds like you have a very capable scope.

Regards,

philsail1

[lunator]

Ritchie

The scope certainly look like a good'un. Very nice images

[RichieJarvis]

I've run CCD Inspector on one of my NGC6888 images:

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Here is the results:

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That looks like an incredibly flat field to me

[FLO]

Nice images Richie

That looks like an incredibly flat field to me

The H9 sensor is only covering the centre so you will see a flat-field, its one of the benefits of the Sony 285 sensor.

[RichieJarvis]

Hi Steve,

Aye - I know - but have you seen the results from Kai's SXV-H9? http://stargazerslounge.com/index.php/topic,35027.0.html

I know thats comparing a doublet with a triplet, but even so, thats double the curvature!

Cheers,

Richie

[FLO]

I know thats comparing a doublet with a triplet, but even so, thats double the curvature!

The third element is not normally used as a field flattener but to improve colour correction, and it is normal when using telescopes of this type to need a separate field flattener when using a DSLR or other large sensor.

The H9 is an excellent match for refractors like yours and Steve's, as both your images demonstrate

[Kai]

I like curvature......

[FLO]

[RichieJarvis]

:laughing3:

[kriss13]

Hi

I hope I'm not highjacking thread, I plan to buy exactly this scope.

For visual use (for now) is it necesary this this field flatener?

Thanks

[John]

Hi

I hope I'm not highjacking thread, I plan to buy exactly this scope.

For visual use (for now) is it necesary this this field flatener?

Thanks

The thread is nearly 4 years old so I don't think anyone will object !

You won't need a flattener for visual use. You might for imaging but I'm no imager.