Digiscoping with Kowa
Kowa's Prominar spotters have a long history in digiscoping, and the TSN-88 and TSN-99 are favorites with birders and long-range shooters who want the best image a phone can pull through glass. We fit the full TSN range, from the compact 500 series to the 99. A Mountain Mag eyepiece stays on your Kowa full-time and your phone attaches magnetically when you want the shot.
Which Mountain Mag eyepiece fits your Kowa optics
We currently fit 8 models (8 spotting scopes). Find yours, then use the link to open the eyepiece with that option already selected. Where several models share one eyepiece it is marked shared eyepiece — order once, it fits all of them.
Spotting scopes
| Model | Mountain Mag eyepiece to order | |
|---|---|---|
| TSN 55 | TSN-55/66/77/88/99 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 553/554 | TSN-553/554/663/664 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 66 | TSN-55/66/77/88/99 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 663/664 | TSN-553/554/663/664 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 773/774 | TSN-55/66/77/88/99 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 88 | TSN-55/66/77/88/99 Prominar (shared eyepiece) | Select this eyepiece |
| TSN 99 | TSN-55/66/77/88/99 Prominar (shared eyepiece) | Select this eyepiece |
| TSN-500/501 Prominar | TSN-500/501 Prominar | Select this eyepiece |
Shop the full Mountain Mag system →
What to know about Kowa optics
Kowa shares eyepieces across its scope bodies, which makes ordering simple. The TSN-55, 66, 773/774, 88 and 99 Prominar all take one Mountain Mag eyepiece. The TSN-553/554 and 663/664 share another. The TSN-500/501 has its own. What matters is the eyepiece on your scope, not the objective, so if you have swapped eyepieces between bodies, order for the eyepiece you actually use.
Models that share one eyepiece
- TSN-55/66/77/88/99 Prominar fits: TSN 55, TSN 66, TSN 773/774, TSN 88, TSN 99
- TSN-553/554/663/664 Prominar fits: TSN 553/554, TSN 663/664
How the Mountain Mag works on Kowa optics
The system is two parts. The Mountain Mag eyepiece contours to the existing eyepiece on your optic and stays there — you glass through it as normal, and it does not have to come off. The Mountain Mag adapter goes on your phone (no special case needed) and snaps onto the eyepiece magnetically, self-centering your camera over the glass. Seat it until you feel the magnets lock and shoot. Pull the phone off when you are done; the eyepiece stays put.
You order the eyepiece by optic model (the table above) and the adapter by phone model (choose your phone here). The Mountain Mag camera app locks your phone to the right lens so it does not hunt between cameras mid-shot.
Frequently asked questions
Does the Mountain Mag fit the Kowa TSN-88 and TSN-99?
Yes. They share one Mountain Mag eyepiece with the TSN-55, TSN-66 and TSN-773/774.
Which eyepiece do I order for a TSN-663 or TSN-553?
The TSN-553/554 and TSN-663/664 share one Mountain Mag eyepiece, listed once in the table above.
Do you fit the small Kowa TSN-500 series?
Yes. The TSN-500 and 501 Prominar have their own eyepiece.
I use a different Kowa eyepiece on my scope body. Which do I order?
Order for the eyepiece you actually have on the scope. The Mountain Mag fits the eyepiece, not the body. If you are unsure, email us the eyepiece model.
Can I leave the eyepiece on my Kowa all the time?
Yes. The Mountain Mag eyepiece is meant to stay on and you glass as normal. The phone adapter attaches magnetically only when you want to shoot.
My Kowa model isn't listed. Can you still fit it?
Often, yes. Check that the eyepiece end is straight and not tapered, measure its outside diameter with digital calipers to the nearest tenth of a millimeter, and send us the reading with your model. We will tell you which eyepiece to order or whether one is coming.
Don't see your model?
We add fitments all the time. Check that the eyepiece end of your optic is straight, not tapered, then measure its outside diameter with digital calipers to the nearest tenth of a millimeter and send us the reading with your brand and model. We will tell you which eyepiece to order, or whether one is on the way.
Digiscoping with other brands
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