Digidapter(™) DLM - Review - 27 Sep 2020
While reading a recent post on the Facebook Digiscoping Gurus Group I saw a comment from Tom Berriman about how much he loved using the Digidapter(™) DLM Adapter for Swarovski ATX/STX scopes. DLM stands for "Direct Lens Mount" and was recently developed by Paul Sayegh to allow the Digidapter to screw directly to the 49mm or 52 mm threads of digiscoping lenses.
I was immediately intrigued by the idea of being able to use a slimmer version of the Digidapter(™) so I contacted Paul and requested a 49mm version for my Swarovski STX85 and 25-60X Zoom Eyepiece. I wanted to compare the alignment and quality to my standard Digidapter(™) bracket adapter. If this adapter was as good as the classic Digidapter(™) then I'd be able to screw it onto the Zeiss 35/2.8 lens attached to my Sony a7III FF digiscoping camera and have a camera/adapter small enough to fit in my Big Pockets Vest pocket while in the field.
Paul was kind enough to take time out of his big move from California to Georgia to mail a copy for me to test and review.
A few days later I received a copy of the adapter in the mail. Its built with the same precision-machined aluminum that goes into every Digidapter(™). The only difference from the bracket adapter is the step-down ring that allows the unit to be attached to the 49mm thread of my Zeiss 35mm / f2.8 digiscoping lens. And, of course, the lack of a platform for the camera...
The DLM slides over the barrel of the eyepiece sleeve as smooth as ever without any tightness or wobble. The attached set screw (plastic) allows the unit to be locked down to the scope eyepiece without any rotation; I tend to leave it off as I like to slip it on and off without the added step of tightening.
The big question was whether the alignment would be good. As mentioned in a previous article I stressed how imprecise alignment causes chromatic aberration (CA) so I tested the connection on the neighbor's white siding. As expected, the alignment was spot on! No CA and a sharp vignette circle at the extreme edges of my FOV.
I was finally able to get out and test the unit at a local birding patch, and the adapter did not disappoint. This Bald Eagle was in a snag at least 500 ft away but still produced a tack sharp image through the scope. Compare the image quality with the Sony a7RIV and 200-600mm at 800mm.
|Bald Eagle. Sony a7RIV + 200-600mm f/5.6-6.3 @ 800mm|
|Bald Eagle. Swarovski STX85, 25-60X eyepiece, Sony a7III, Zeiss 35/2.8, Digidapter DLM|
A Great Egret was fishing in the channel about 200 ft. away. Again, the Digidapter(™) DLM produced sharp images with no evidence of CA. Alignment looks good even at a distance.
Same for this Great Blue Heron.
One final test was video capturing a kettle of Broad-winged Hawks at the Detroit River Hawk Watch. I zoomed the scope in to about 30X and digiscoped the kettle a half-mile away. Hands free the DLM supported the weight of the Sony a7III and Zeiss 35/2.8 with no problems. Caution: Don't carry the scope with the unit attached as you could damage the lens/threads.