D&G 5" f10 First Light Coming!

Periodically I see posts asking about D&G achromat OTAs and and achromatic objectives.

I ordered one of the most recent "Limited Run" 5" f10 OTAs from D&G almost one year ago. I had intended to use the scope for the Mars opposition last summer.

Unfortunately I didn't receive the scope until December, well after the opposition. I am still waiting for the Astro-Physics focuser which is on backorder (surprise, surprise). D&G did everything possible to make up for the delays, including installing a generic 2" Chinese focuser as a temporary while I wait for D&G to receive the A-P unit.

The scope arrived in two separate parcels - lens cell and finder with brackets in one box, OTA in a long cardboard tube. The lens cell was wrapped in tissue paper with cardboard discs over each glass-to-air surface. I mounted the objective to the OTA, per the enclosed directions. My fingers are crossed as to whether it is properly squared off and retained collimation. Not a tragedy if it dodn't since the objective uses nice push-pull allen screws for collimation. Another glitch was that the Parallax tube rings ordered with the OTA oh-so-many-months-ago didn't come as didn't the objective dust cover. Those were sent proptly upon e-mail request.

The objective is MgFl coated rather than multi-coated. It appears to be a very nice coating job, with no sleaks or imperfections apparent. The OTA assembly itself is quite large, even at f/10. The whole thing looks a little "home brewed" but that adds to its charm. For example, the dust cover for the objective looks like a cookie jar lid, is paitend flat black and is made of wood.

I have the scope mounted on a Losmandy GM-8. She sees first light this weekend. I'll report back on the optics then.

James
Congratulations.

I think you will find collimation very easy to sort out.

I have owned the 6 inch f -12 and it took one half turn of a push or pull screw to collimate after rough alignment with my eye looking down the tube. The scope stayed aligned for the year and a half I owned it. I was very impressed with the optical quality. I sold it because of the strain on my mount and because of a lack of portability.

Certainly sharper and with more contrast than the run of the mill achromats of shorter focal ratio. I was surprised how good the scope was with respect to star clusters. And as for double stars the performance was remarkable.

Best wishes

Kevin

First light regretably postponed due to resumed rain in northern California .

I'll keep you posted...